JP5632167B2 - Polylactic acid resin composition - Google Patents

Description

  The present invention comprises a stereocomplex polylactic acid (component A), a phosphoric acid ester metal salt (component B), and a carbodiimide compound (component C) containing a cyclic structure, and has improved heat resistance and moist heat resistance stability. The present invention relates to a lactic acid composition.

  In recent years, for the purpose of protecting the global environment, biodegradable polymers that are decomposed in a natural environment have attracted attention and are being studied all over the world. As biodegradable polymers, aliphatic polyesters such as polylactic acid, polyhydroxybutyrate and polycaprolactone are known. Since polylactic acid uses lactic acid obtained from a raw material derived from a living body or a derivative thereof as a raw material, it is a high-safety and environmentally friendly polymer material. Therefore, the use as a general-purpose polymer is examined, and the use as a stretched film, a fiber, an injection molded product, etc. is examined.

  However, polylactic acid has a low crystal melting temperature of about 155 ° C., so there is a limit to heat resistance, and since it is easily decomposed by humidity, there is a limit to heat and heat resistance stability. There was a limit to formability as well as use as a molded product.

  In order to improve the moldability and heat resistance of polylactic acid, poly-L-lactic acid composed of L-lactic acid units (hereinafter sometimes abbreviated as PLLA) and poly-D-lactic acid composed of D-lactic acid units (hereinafter referred to as PDLA). Are mixed in a solution or in a molten state, and a phosphoric acid ester metal salt is used as a crystallization nucleating agent to form a stereocomplex polylactic acid to promote crystallization and improve heat resistance. A method to do this has been proposed (Patent Document 1). Since the stereocomplex polylactic acid obtained by this method has a higher crystal melting temperature than the homophase polylactic acid, it needs to be processed at a higher temperature than the homophase polylactic acid. Therefore, there has been a problem that it is more susceptible to hydrolysis due to humidity.

  In order to improve the wet heat stability of polylactic acid, it has been proposed to improve the heat and heat resistance stability by sealing carboxyl end groups with a carbodiimide compound (see, for example, Patent Documents 2 and 3), and some results have been seen. ing. The carbodiimide compound used in this proposal is a linear carbodiimide compound. When a linear carbodiimide compound is used as a terminal group blocking agent for a polymer compound, a compound having an isocyanate group is released along with a reaction in which the linear carbodiimide compound is bonded to the terminal group of polylactic acid, generating a unique odor of the isocyanate compound. However, deteriorating the working environment has become a problem, and this problem remains unsolved.

JP 2003-192894 A Japanese Patent No. 3440915 Japanese Patent No. 3776578

  An object of the present invention is to provide a polylactic acid resin composition that solves the problems of the prior art, has improved heat resistance and moist heat stability, and does not generate a free isocyanate compound.

The present inventors diligently studied a carbodiimide compound having a structure that does not liberate an isocyanate compound even when it reacts with an end group of polylactic acid.
As a result, a compound containing a cyclic structure in which one carbodiimide group and the first nitrogen and the second nitrogen are bonded by a linking group (a compound having a carbodiimide group in the cyclic structure, hereinafter referred to as a cyclic carbodiimide compound and The present invention has been completed by finding that an isocyanate compound is not liberated even if it reacts with a terminal group of polylactic acid.

（式中Ｒ _１ は水素原子または炭素原子数１〜４のアルキル基である。Ｒ _２ およびＲ _３ はそれぞれ独立に水素原子または炭素原子数１〜１２のアルキル基である。Ｍ _１ はアルカリ金属原子、アルカリ土類金属原子、亜鉛原子またはアルミニウム原子である。ｐは１または２である。ｑはＭ _１ がアルカリ金属原子、アルカリ土類金属原子または亜鉛原子のときは０、アルミニウム原子のときは１または２である。）

（式中、Ｑは、下記式（１−１）、（１−２）または（１−３）で表される２〜４価の結合基である。）

（式中、Ａｒ ^１ およびＡｒ ^２ は各々独立に、２〜４価の炭素数５〜１５の芳香族基である。Ｒ ^１ およびＲ ^２ は各々独立に、２〜４価の炭素数１〜２０の脂肪族基、２〜４価の炭素数３〜２０の脂環族基またはこれらの組み合わせ、またはこれら脂肪族基、脂環族基と２〜４価の炭素数５〜１５の芳香族基の組み合わせである。Ｘ ^１ およびＸ ^２ は各々独立に、２〜４価の炭素数１〜２０の脂肪族基、２〜４価の炭素数３〜２０の脂環族基、２〜４価の炭素数５〜１５の芳香族基、またはこれらの組み合わせである。ｓは０〜１０の整数である。ｋは０〜１０の整数である。なお、ｓまたはｋが２以上であるとき、繰り返し単位としてのＸ ^１ 、あるいはＸ ^２ が、他のＸ ^１ 、あるいはＸ ^２ と異なっていてもよい。Ｘ ^３ は、２〜４価の炭素数１〜２０の脂肪族基、２〜４価の炭素数３〜２０の脂環族基、２〜４価の炭素数５〜１５の芳香族基、またはこれらの組み合わせである。但し、Ａｒ ^１ 、Ａｒ ^２ 、Ｒ ^１ 、Ｒ ^２ 、Ｘ ^１ 、Ｘ ^２ およびＸ ^３ はヘテロ原子を含有していてもよい、また、Ｑが２価の結合基であるときは、Ａｒ ^１ 、Ａｒ ^２ 、Ｒ ^１ 、Ｒ ^２ 、Ｘ ^１ 、Ｘ ^２ およびＸ ^３ は全て２価の基である。Ｑが３価の結合基であるときは、Ａｒ ^１ 、Ａｒ ^２ 、Ｒ ^１ 、Ｒ ^２ 、Ｘ ^１ 、Ｘ ^２ およびＸ ^３ の内の一つが３価の基である。Ｑが４価の結合基であるときは、Ａｒ ^１ 、Ａｒ ^２ 、Ｒ ^１ 、Ｒ ^２ 、Ｘ ^１ 、Ｘ ^２ およびＸ ^３ の内の一つが４価の基であるか、二つが３価の基である。） That is, the object of the present invention is to
Stereocomplex polylactic acid (component (A)), coupled by-phosphate ester metal salt (component (B)) and having one carbodiimide group The first nitrogen and second nitrogen and bond group represented by the following formula (ii) the in which cyclic structure is can be achieved by a polylactic acid resin composition containing including the following formula (1) represented by reduction compounds with the component (C).

(In the formula, R ₁ is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. R ₂ and R ₃ are each independently a hydrogen atom or an alkyl group having 1 to 12 carbon atoms. M ₁ is an alkali metal. An atom, an alkaline earth metal atom, a zinc atom or an aluminum atom, p is 1 or 2. q is 0 when M ₁ is an alkali metal atom, an alkaline earth metal atom or a zinc atom, and is an aluminum atom. Is 1 or 2.)

(In the formula, Q is a divalent to tetravalent linking group represented by the following formula (1-1), (1-2) or (1-3)).

(In the formula, Ar ¹ and Ar ² are each independently an aromatic group having 2 to 4 carbon atoms and 5 to 15 carbon atoms. R ¹ and R ² are each independently 1 to 2 carbon atoms having 1 to 4 carbon atoms. 20 aliphatic groups, 2 to 4 valent alicyclic groups having 3 to 20 carbon atoms, or combinations thereof, or these aliphatic groups, alicyclic groups and 2 to 4 valent aromatic carbon atoms having 5 to 15 carbon atoms X ¹ and X ² are each independently a divalent to tetravalent aliphatic group having 1 to 20 carbon atoms, a divalent to tetravalent carbon atom having 3 to 20 alicyclic groups, 2 to 4 A valent aromatic group having 5 to 15 carbon atoms, or a combination thereof, s is an integer of 0 to 10. k is an integer of 0 to 10. When s or k is 2 or more, X ¹ or X ² as a repeating unit may be different from other X ¹ or X ^2. X ³ is a divalent to tetravalent carbon number. An aliphatic group having 1 to 20 carbon atoms, an alicyclic group having 2 to 4 carbon atoms having 3 to 20 carbon atoms, an aromatic group having 2 to 4 carbon atoms having 5 to 15 carbon atoms, or a combination thereof, provided that Ar ¹ , Ar ² , R ¹ , R ² , X ¹ , X ² and X ³ may contain a hetero atom, and when Q is a divalent linking group, Ar ¹ , Ar ² , R 3 ¹ , R ² , X ¹ , X ² and X ³ are all divalent groups, and when Q is a trivalent linking group, Ar ¹ , Ar ² , R ¹ , R ² , X ¹ , X one of the ² and ^{X 3} is a trivalent radical when .Q is a tetravalent linking ^group, among ^{Ar 1, Ar 2, R 1} , R 2, X 1, X 2 and ^{X 3} One of them is a tetravalent group or two are trivalent groups.)

  According to the present invention, it is possible to provide a polylactic acid resin composition which has improved heat resistance and wet heat stability and does not generate a free isocyanate compound.

Hereinafter, the present invention will be described in detail.
<Polylactic acid resin composition>
(Stereo complex polylactic acid (component A))
The polylactic acid resin composition of the present invention contains stereocomplex polylactic acid. Stereocomplex polylactic acid is polylactic acid containing stereocomplex crystals.

  Stereocomplex polylactic acid mainly consists of a polylactic acid unit (iA) composed of L-lactic acid units represented by the following formula or a polylactic acid unit (iiA) composed of D-lactic acid units represented by the following formula.

  As the polylactic acid unit (iA) and the polylactic acid unit (iiA), the polylactic acid unit (iA) is mainly composed of L-lactic acid units. A D-lactic acid unit and / or a copolymer component unit other than lactic acid may be included. The L-lactic acid unit is 90 mol% or more and 100 mol% or less. Preferably they are 95 mol% or more and 100 mol% or less, More preferably, they are 98 mol% or more and 100 mol% or less. The D-lactic acid unit and / or the copolymer component unit other than lactic acid is 0 mol% or more and 10 mol% or less. Preferably they are 0 mol% or more and 5 mol% or less, More preferably, they are 0 mol% or more and 2 mol% or less.

  The polylactic acid unit (iiA) is mainly composed of D-lactic acid units. An L-lactic acid unit and / or a copolymer component unit other than lactic acid may be included. The D-lactic acid unit is 90 mol% or more and 100 mol% or less. Preferably they are 95 mol% or more and 100 mol% or less, More preferably, they are 98 mol% or more and 100 mol% or less. The L-lactic acid unit and / or the copolymer component unit other than lactic acid is 0 mol% or more and 10 mol% or less. Preferably they are 0 mol% or more and 5 mol% or less, More preferably, they are 0 mol% or more and 2 mol% or less.

  The copolymer component unit in the polylactic acid unit (iA) and the polylactic acid unit (iiA) is a unit derived from a dicarboxylic acid, a polyhydric alcohol, a hydroxycarboxylic acid, a lactone or the like having a functional group capable of forming two or more ester bonds. Units derived from various polyesters, various polyethers, various polycarbonates and the like comprising these various components can be used alone or in combination.

  Examples of the dicarboxylic acid include succinic acid, adipic acid, azelaic acid, sebacic acid, terephthalic acid, and isophthalic acid. Examples of polyhydric alcohols include aliphatic polyhydric alcohols such as ethylene glycol, propylene glycol, butanediol, pentanediol, hexanediol, octanediol, glycerin, sorbitan, neopentyl glycol, diethylene glycol, triethylene glycol, polyethylene glycol, and polypropylene glycol. Or aromatic polyhydric alcohol etc., such as what added ethylene oxide to bisphenol, etc. are mentioned. Examples of the hydroxycarboxylic acid include glycolic acid and hydroxybutylcarboxylic acid. Examples of the lactone include glycolide, ε-caprolactone glycolide, ε-caprolactone, β-propiolactone, δ-butyrolactone, β- or γ-butyrolactone, pivalolactone, δ-valerolactone, and the like.

  As the stereocomplex polylactic acid, those having various end group cappings on the end groups may be used. Examples of such end group blocking groups include acetyl groups, ester groups, ether groups, amide groups, urethane groups, and the like.

  The stereocomplex polylactic acid may contain a catalyst involved in polymerization within a range that does not impair the thermal stability of the polylactic acid resin composition. As such a catalyst, various tin compounds, titanium compounds, calcium compounds, organic acids, inorganic acids, and the like can be raised, and at the same time, a stabilizer that inactivates them may coexist.

  The molecular weight and molecular weight distribution of the stereocomplex polylactic acid are not particularly limited as long as it can be substantially molded. However, the weight average molecular weight is 100,000 to 500,000, and both moldability and molded article physical properties are compatible. It is preferably selected from the viewpoint of If the weight average molecular weight is less than 100,000, the mechanical strength and toughness of the molded product are low, which is not preferable. Further, if the weight average molecular weight exceeds 500,000, the melt viscosity is high, and melt molding becomes difficult. From this viewpoint, the weight average molecular weight is more preferably selected in the range of 110,000 to 350,000, and more preferably in the range of 1 to 250,000. The weight average molecular weight is a standard polystyrene equivalent weight average molecular weight value measured by gel permeation chromatography (GPC) using chloroform as an eluent.

In the polylactic acid resin composition of the present invention, two melting peaks at a low temperature (140 to 180 ° C.) and a high temperature (190 ° C. or higher) or a high temperature melting in the temperature rising process of the differential scanning calorimeter (DSC) measurement. Only peaks are observed. Among these, the low-temperature melting peak is derived from the homophase polylactic acid crystal, and the high-temperature melting peak is derived from the stereocomplex phase polylactic acid crystal. From the viewpoint of heat resistance, the polycomplex lactic acid resin composition of the present invention has a stereocomplex crystallinity (S) defined by the following formula in DSC measurement of 90 to exhibit the heat resistance inherent in stereocomplex polylactic acid. -100% is preferable, 95-100% is more preferable, and 100% is particularly preferable.
S = [ΔHms / (ΔHmh + ΔHms)] × 100
(However, ΔHms = melting enthalpy of stereocomplex phase polylactic acid crystals, ΔHmh = melting enthalpy of homophase polylactic acid crystals)

The stereocomplex polylactic acid in the polylactic acid resin composition of the present invention preferably has crystallinity, and the stereocomplex defined by the following formula according to the intensity ratio of diffraction peaks by wide-angle X-ray diffraction (XRD) measurement. The crystallization rate (Sc) is more preferably 50% or more.
Sc (%) = [ΣI _SCi / (ΣI _SCi + I _HM )] × 100
(Where ΣI _SCi = I _SC1 + I _SC2 + I _SC3 and I _SCi (i = 1 to 3) are the integrated intensities of diffraction peaks around 2θ = 12.0 °, 20.7 °, and 24.0 °, respectively. I _HM represents the integrated intensity I _HM of a diffraction peak derived from a homophase crystal appearing in the vicinity of 2θ = 16.5 °.

  The stereocomplex crystallization ratio (Sc) is preferably selected in the range of 50 to 100%, more preferably 60 to 95%, and particularly preferably 65 to 90%. That is, when the polylactic acid has Sc in the above range, the heat resistance and heat-and-moisture resistance of the molded product are more preferably satisfied.

  From the same viewpoint, the melting point of the stereocomplex phase polylactic acid crystal is preferably 190 to 250 ° C, more preferably 200 to 230 ° C. The crystal melting enthalpy of the stereocomplex phase polylactic acid crystal by DSC measurement is 20 J / g or more, preferably 20 to 80 J / g, more preferably 30 to 80 J / g.

  If the melting point of the stereocomplex phase polylactic acid crystal is less than 190 ° C., the significance of the formation of the stereocomplex phase, and hence the significance of the present invention will be small. Further, when the temperature exceeds 250 ° C., it is necessary to mold the molded product of the present invention at a high temperature of 250 ° C. or higher, and it may be difficult to suppress thermal decomposition of the resin. A similar argument applies to the value of the stereocomplex phase polylactic acid crystal melting enthalpy.

  In order to suitably satisfy the stereocomplex crystallinity, melting point and crystal melting enthalpy values, in the stereocomplex polylactic acid (component A), the weight ratio of poly L-lactic acid to poly D-lactic acid is 90:10 to 10:90. It is preferable that More preferably, it is in the range of 80:20 to 20:80, still more preferably 30:70 to 70:30, particularly preferably 40:60 to 60:40, and theoretically it is preferably as close as possible to 50:50. .

  Poly L-lactic acid and poly D-lactic acid can be produced by a conventionally known method. For example, it can be produced by ring-opening polymerization of L- or D-lactide in the presence of a metal-containing catalyst. The low molecular weight polylactic acid containing a metal-containing catalyst is optionally crystallized or without crystallization, under reduced pressure or from normal pressure to increased pressure, in the presence or absence of an inert gas stream. It can also be produced by solid phase polymerization. Furthermore, it can be produced by a direct polymerization method in which lactic acid is subjected to dehydration condensation in the presence or absence of an organic solvent.

  The polymerization reaction can be carried out in a conventionally known reaction vessel. For example, in ring-opening polymerization or direct polymerization method, a vertical reactor or a horizontal reactor equipped with a stirring blade for high viscosity, such as a helical ribbon blade, is used alone, or Can be used in parallel. Moreover, any of a batch type, a continuous type, a semibatch type may be sufficient, and these may be combined.

  Alcohol may be used as a polymerization initiator. Such alcohol is preferably non-volatile without inhibiting the polymerization of polylactic acid, such as decanol, dodecanol, tetradecanol, hexadecanol, octadecanol, ethylene glycol, trimethylolpropane, pentaerythritol, etc. Can be suitably used.

  It can be said that the polylactic acid prepolymer used in the solid-phase polymerization method is preferably crystallized in advance from the viewpoint of preventing resin pellet fusion. The prepolymer is polymerized in a solid state in a fixed vertical or horizontal reaction vessel, or in a reaction vessel (such as a rotary kiln) that rotates itself like a tumbler or kiln, in the temperature range from the glass transition temperature of the prepolymer to less than the melting point. Is done.

  Examples of metal catalysts include alkali metals, alkaline earth metals, rare earths, transition metals, aluminum, germanium, tin, antimony, titanium and other fatty acid salts, carbonates, sulfates, phosphates, oxides, hydroxides, Illustrative are halides, alcoholates and the like. Among them, fatty acid salts, carbonates, sulfates, phosphates, oxides, hydroxides containing at least one metal selected from tin, aluminum, zinc, calcium, titanium, germanium, manganese, magnesium and rare earth elements Products, halides, and alcoholates are preferred.

  Tin compounds due to low catalytic activity and side reactions, specifically stannous chloride, stannous bromide, stannous iodide, stannous sulfate, stannic oxide, tin myristate, tin octylate Tin-containing compounds such as tin stearate and tetraphenyltin are exemplified as preferred catalysts.

  Among these, tin (II) compounds, specifically, diethoxytin, dinonyloxytin, tin (II) myristate, tin (II) octylate, tin (II) stearate, tin (II) chloride and the like are suitable. Illustrated.

The amount of the catalyst used is 0.42 × 10 ^{−4 to} 100 × 10 ⁻⁴ mol per kg of lactide, and further considering the reactivity, color tone and stability of the resulting polylactides, 1.68 × 10 ^{−4 to} 42 0.1 × 10 ⁻⁴ mol, particularly preferably 2.53 × 10 ^{−4 to} 16.8 × 10 ⁻⁴ mol are used.

The metal-containing catalyst used for polylactic acid polymerization is preferably deactivated with a conventionally known deactivator prior to using polylactic acid.
Examples of such a deactivator include an organic ligand consisting of a group of chelate ligands having an imino group and capable of coordinating to a polymerized metal catalyst, dihydridooxoline (I) acid, dihydridotetraoxodilin (II, II ) Acid, hydridotrioxoline (III) acid, dihydridopentaoxodiphosphorus (III) acid, hydridopentaoxodi (II, IV) acid, dodecaoxohexaphosphorus (III) acid, hydridooctaoxotriphosphate (III, IV) , IV) acid, octaoxotriphosphoric acid (IV, III, IV), hydridohexaoxodiphosphoric acid (III, V), hexaoxodiphosphoric acid (IV), decaoxotetralinic acid (IV), hedecaoxotetralinic acid (IV ) acid, Eneaokiso triphosphate (V, IV, IV) acid value 5 or less low oxidation number phosphoric acids such as acid, the formula _xH 2 _O · _yP 2 O ₅ Polyphosphoric acid represented by x, y = 3, 2> x / y> 1, and referred to as diphosphoric acid, triphosphoric acid, tetraphosphoric acid, pentaphosphoric acid or the like based on the degree of condensation, and mixtures thereof , X / y = 1, especially trimetaphosphoric acid, tetrametaphosphoric acid, 1> x / y> 0, ultralin having a network structure with a part of the phosphorus pentoxide structure Acids (sometimes collectively referred to as metaphosphate compounds), and acid salts of these acids, monovalent and polyhydric alcohols, or partial esters, complete esters, phosphono substitutions of polyalkylene glycols Examples include lower aliphatic carboxylic acid derivatives.

From the catalyst deactivation ability, it is represented by the formula xH ₂ O · yP ₂ O ₅ , x / y = 3 orthophosphoric acid, 2> x / y> 1, and based on the degree of condensation, diphosphate, triphosphate, tetra Polyphosphoric acid called phosphoric acid, pentaphosphoric acid and the like and mixtures thereof, metaphosphoric acid represented by x / y = 1, especially trimetaphosphoric acid, tetrametaphosphoric acid, 1> x / y> 0, Ultraphosphoric acid having a network structure with a part of the phosphorus oxide structure (these may be collectively referred to as metaphosphoric acid compounds), and acid salts of these acids, monovalent and polyhydric alcohols Or partial ester phosphorus oxoacids of polyalkylene glycols or acidic esters thereof, phosphono-substituted lower aliphatic carboxylic acid derivatives and the above-mentioned metaphosphoric acid compounds are preferably used.

  The metaphosphoric acid compound used in the present invention is a cyclic metaphosphoric acid in which about 3 to 200 phosphoric acid units are condensed, an ultra-region metaphosphoric acid having a three-dimensional network structure, or an alkali metal salt or an alkaline earth metal salt thereof. Onium salts). Among them, cyclic sodium metaphosphate, ultra-region sodium metaphosphate, phosphono-substituted lower aliphatic carboxylic acid derivative dihexylphosphonoethyl acetate (hereinafter sometimes abbreviated as DHPA) and the like are preferably used.

  The stereocomplex polylactic acid (component A) preferably has a lactide content of 1 to 5,000 wtppm. The lactide contained in the stereocomplex polylactic acid (component A) deteriorates the resin and deteriorates the color tone at the time of melt processing, and may be rendered unusable as a product.

  Poly L-lactic acid and / or poly D-lactic acid immediately after the melt ring-opening polymerization usually contains 1 to 5% by weight of lactide, but is molded from the end of the polymerization of poly L-lactic acid and / or poly D-lactic acid. At any stage up to the above, a conventionally known lactide weight loss method, that is, a vacuum devolatilization method in a single or multi-screw extruder, or a high vacuum treatment in a polymerization apparatus is carried out alone or in combination. In addition, lactide can be reduced to a suitable range.

  The smaller the lactide content, the better the melt stability and heat-and-moisture resistance of the resin, but there is also the advantage of lowering the resin melt viscosity, making it reasonable and economical to meet the desired purpose. is there. That is, it is reasonable to set it to 1 to 1,000 wtppm at which practical melt stability is achieved. More preferably, a range of 1 to 700 wtppm, more preferably 2 to 500 wtppm, and particularly preferably 5 to 100 wtppm is selected.

  The advantage that the stereocomplex polylactic acid (component A) has a lactide content in such a range can improve the stability of the resin during melt molding of the molded product of the present invention, and the molded product can be efficiently manufactured and the molded product It is possible to improve the heat-and-moisture stability and low gas resistance.

  Stereocomplex polylactic acid (component A) is made by bringing poly L-lactic acid and poly D-lactic acid in a weight ratio in the range of 10/90 to 90/10, preferably by melt contact, and more preferably by melting. It can be obtained by kneading.

  The contact temperature is selected in the range of 220 to 290 ° C., preferably 220 to 280 ° C., and more preferably 225 to 275 ° C. from the viewpoint of improving the stability of polylactic acid when melted and the stereocomplex crystallinity.

  The melt kneading method is not particularly limited, but a conventionally known batch type or continuous type melt mixing apparatus is preferably used. For example, melt-stirred tanks, single- and twin-screw extruders, kneaders, non-shaft vertical stirrers, "Vibolac" manufactured by Sumitomo Heavy Industries, Ltd., N-SCR manufactured by Mitsubishi Heavy Industries, Ltd., Hitachi, Ltd. You can use glass blades, lattice blades or Kenix type stirrers, or Sulzer type SMLX type static mixer equipped pipe type polymerization equipment, but it is a self-cleaning type polymerization equipment in terms of productivity, quality of polylactic acid, especially color tone. A certain non-shaft vertical stirring tank, N-SCR, twin-screw extruder, etc. are preferably used.

<Phosphate metal salt (component B)>
The stereocomplex polylactic acid (component A) used in the present invention contains a phosphate ester metal salt (component B) as a stereocomplex crystallization accelerator in order to promote the formation of a stereocomplex phase stably and highly. Compound represented by the following formula (ii) as such agent Ru is selected.

(Wherein R ₁ is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. R ₂ and R 3 are each independently a hydrogen atom or an alkyl group having 1 to 12 carbon atoms. M1 is an alkali metal atom, An alkaline earth metal atom, a zinc atom or an aluminum atom, p is 1 or 2. q is 0 when M1 is an alkali metal atom, an alkaline earth metal atom or a zinc atom, or 1 when M1 is an aluminum atom. 2)

  The phosphoric acid ester metal salt (component B) preferably has an acid value of less than 5. Reduction of the acid value can be achieved by dissolving or dispersing the component B in a low-boiling anhydrous solvent and treating with a strongly basic compound. When the acid value of component B exceeds 2, the heat and heat resistance of stereocomplex polylactic acid (component A) may be significantly deteriorated beyond the scope of the present invention. The acid value of the component B is preferably in the range of 0 to 4, more preferably in the range of 0.01 to 3, more preferably in the range of 0.1 to 2.

In these phosphoric acid ester metal salts, M ₁ and M ₂ are preferably Na, K, Al, Mg and Ca, and in particular, K, Na, Al, and especially Al can be most suitably used. Among them, trade names of “ADEKA STAB” NA-10, NA-11, NA-21, NA-30, NA-35, NA-71 and the like manufactured by ADEKA are exemplified as suitable agents.

  The content of the phosphate ester metal salt (component C) is 0.01 to 5 parts by weight, preferably 0.01 to 1 part by weight, more preferably 100 parts by weight of stereocomplex polylactic acid (component A). Is 0.02 to 0.3 parts by weight. When the amount is too small, the effect of improving the degree of crystallinity of the stereocomplex is small, and when too large, the stereocomplex phase melting point is lowered, which is not preferable.

  The phosphoric acid ester metal salt (component B) is necessary to increase the stereocomplex crystallinity (S) of the stereocomplex polylactic acid (component A), but may reduce the wet heat resistance of the polylactic acid. For this reason, the undesirable action of the B component can be suitably suppressed by including the cyclic carbodiimide compound (C component). Furthermore, it is speculated that the cyclic carbodiimide compound (component C) reacts with the molecular end of stereocomplex polylactic acid (component A) to partially connect the poly L-lactic acid unit and the poly D-lactic acid unit. An effect as a stereocomplex crystallization aid that promotes the stereocomplex phase forming effect of the salt (component B) can be expected.

(Cyclic carbodiimide compound (component C))
In the present invention, the cyclic carbodiimide compound (C component) has a cyclic structure. The cyclic carbodiimide compound may have a plurality of cyclic structures.
The cyclic structure has one carbodiimide group (—N═C═N—), and the first nitrogen and the second nitrogen are bonded by a bonding group. One cyclic structure has only one carbodiimide group. The number of atoms in the cyclic structure is preferably 8 to 50, more preferably 10 to 30, further preferably 10 to 20, and particularly preferably 10 to 15.

  Here, the number of atoms in the ring structure means the number of atoms that directly constitute the ring structure, and is, for example, 8 for an 8-membered ring and 50 for a 50-membered ring. This is because if the number of atoms in the cyclic structure is smaller than 8, the stability of the cyclic carbodiimide compound is lowered, and it may be difficult to store and use. From the viewpoint of reactivity, there is no particular restriction on the upper limit of the number of ring members, but cyclic carbodiimide compounds having more than 50 atoms are difficult to synthesize, and the cost may increase significantly. From this viewpoint, the number of atoms in the cyclic structure is preferably selected in the range of 10 to 30, more preferably 10 to 20, and particularly 10 to 15.

Cyclic structure, Ru structure der represented by the following formula (1).

In the formula, the linking group (Q) is a divalent to tetravalent linking group represented by the following formula (1-1), (1-2) or (1-3).

In the formula, Ar ¹ and Ar ² are each independently a 2- to 4-valent aromatic group having 5 to 15 carbon atoms which may contain a hetero atom and a substituent.
As an aromatic group, each of which contains a hetero atom and may have a heterocyclic structure, an arylene group having 5 to 15 carbon atoms, an arenetriyl group having 5 to 15 carbon atoms, an arenetetra having 5 to 15 carbon atoms Yl group. Examples of the arylene group (divalent) include a phenylene group and a naphthalenediyl group. Examples of the arenetriyl group (trivalent) include a benzenetriyl group and a naphthalenetriyl group. Examples of the arenetetrayl group (tetravalent) include a benzenetetrayl group and a naphthalenetetrayl group. These aromatic groups may be substituted. Examples of the substituent include an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 15 carbon atoms, a halogen atom, a nitro group, an amide group, a hydroxyl group, an ester group, an ether group, and an aldehyde group.

R ¹ and R ² each independently contain a heteroatom and a substituent, each having 2 to 4 valent aliphatic groups having 1 to 20 carbon atoms and 2 to 4 valent fatty acids having 3 to 20 carbon atoms A cyclic group, and a combination thereof, or a combination of the aliphatic group, the alicyclic group, and a divalent to tetravalent aromatic group having 5 to 15 carbon atoms.

  Examples of the aliphatic group include an alkylene group having 1 to 20 carbon atoms, an alkanetriyl group having 1 to 20 carbon atoms, and an alkanetetrayl group having 1 to 20 carbon atoms. Examples of the alkylene group include a methylene group, an ethylene group, a propylene group, a butylene group, a pentylene group, a hexylene group, a heptylene group, an octylene group, a nonylene group, a decylene group, a dodecylene group, and a hexadecylene group. As the alkanetriyl group, methanetriyl group, ethanetriyl group, propanetriyl group, butanetriyl group, pentanetriyl group, hexanetriyl group, heptanetriyl group, octanetriyl group, nonanetriyl group, decantriyl group, dodecantriyl group, Examples include a hexadecantriyl group. As alkanetetrayl group, methanetetrayl group, ethanetetrayl group, propanetetrayl group, butanetetrayl group, pentanetetrayl group, hexanetetrayl group, heptanetetrayl group, octanetetrayl group, nonanetetrayl group Decanetetrayl group, dodecanetetrayl group, hexadecanetetrayl group and the like. These aliphatic groups may be substituted. Examples of the substituent include an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 15 carbon atoms, a halogen atom, a nitro group, an amide group, a hydroxyl group, an ester group, an ether group, and an aldehyde group.

  Examples of the alicyclic group include a cycloalkylene group having 3 to 20 carbon atoms, a cycloalkanetriyl group having 3 to 20 carbon atoms, and a cycloalkanetetrayl group having 3 to 20 carbon atoms. Examples of the cycloalkylene group include a cyclopropylene group, a cyclobutylene group, a cyclopentylene group, a cyclohexylene group, a cycloheptylene group, a cyclooctylene group, a cyclononylene group, a cyclodecylene group, a cyclododecylene group, and a cyclohexadecylene group. As cycloalkanetriyl group, cyclopropanetriyl group, cyclobutanetriyl group, cyclopentanetriyl group, cyclohexanetriyl group, cycloheptanetriyl group, cyclooctanetriyl group, cyclononanetriyl group, cyclodecanetriyl group Group, cyclododecane triyl group, cyclohexadecane triyl group and the like. As cycloalkanetetrayl group, cyclopropanetetrayl group, cyclobutanetetrayl group, cyclopentanetetrayl group, cyclohexanetetrayl group, cycloheptanetetrayl group, cyclooctanetetrayl group, cyclononanetetrayl group, cyclodecanetetrayl group Yl group, cyclododecanetetrayl group, cyclohexadecanetetrayl group and the like. These alicyclic groups may be substituted. Examples of the substituent include an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 15 carbon atoms, a halogen atom, a nitro group, an amide group, a hydroxyl group, an ester group, an ether group, and an aldehyde group.

  As an aromatic group, each of which contains a hetero atom and may have a heterocyclic structure, an arylene group having 5 to 15 carbon atoms, an arenetriyl group having 5 to 15 carbon atoms, an arenetetra having 5 to 15 carbon atoms Yl group. Examples of the arylene group include a phenylene group and a naphthalenediyl group. Examples of the arenetriyl group (trivalent) include a benzenetriyl group and a naphthalenetriyl group. Examples of the arenetetrayl group (tetravalent) include a benzenetetrayl group and a naphthalenetetrayl group. These aromatic groups may be substituted. Examples of the substituent include an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 15 carbon atoms, a halogen atom, a nitro group, an amide group, a hydroxyl group, an ester group, an ether group, and an aldehyde group.

X ¹ and X ² each independently contain a heteroatom and a substituent, each having a 2 to 4 valent aliphatic group having 1 to 20 carbon atoms and a 2 to 4 valent fatty acid having 3 to 20 carbon atoms It is a cyclic group, a divalent to tetravalent aromatic group having 5 to 15 carbon atoms, or a combination thereof.

  Examples of the aliphatic group include an alkylene group having 1 to 20 carbon atoms, an alkanetriyl group having 1 to 20 carbon atoms, and an alkanetetrayl group having 1 to 20 carbon atoms. Examples of the alkylene group include a methylene group, an ethylene group, a propylene group, a butylene group, a pentylene group, a hexylene group, a heptylene group, an octylene group, a nonylene group, a decylene group, a dodecylene group, and a hexadecylene group. As the alkanetriyl group, methanetriyl group, ethanetriyl group, propanetriyl group, butanetriyl group, pentanetriyl group, hexanetriyl group, heptanetriyl group, octanetriyl group, nonanetriyl group, decantriyl group, dodecantriyl group, Examples include a hexadecantriyl group. As alkanetetrayl group, methanetetrayl group, ethanetetrayl group, propanetetrayl group, butanetetrayl group, pentanetetrayl group, hexanetetrayl group, heptanetetrayl group, octanetetrayl group, nonanetetrayl group Decanetetrayl group, dodecanetetrayl group, hexadecanetetrayl group and the like. These aliphatic groups may be substituted. Examples of the substituent include an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 15 carbon atoms, a halogen atom, a nitro group, an amide group, a hydroxyl group, an ester group, an ether group, and an aldehyde group.

  Examples of the alicyclic group include a cycloalkylene group having 3 to 20 carbon atoms, a cycloalkanetriyl group having 3 to 20 carbon atoms, and a cycloalkanetetrayl group having 3 to 20 carbon atoms. Examples of the cycloalkylene group include a cyclopropylene group, a cyclobutylene group, a cyclopentylene group, a cyclohexylene group, a cycloheptylene group, a cyclooctylene group, a cyclononylene group, a cyclodecylene group, a cyclododecylene group, and a cyclohexadecylene group. As the alkanetriyl group, cyclopropanetriyl group, cyclobutanetriyl group, cyclopentanetriyl group, cyclohexanetriyl group, cycloheptanetriyl group, cyclooctanetriyl group, cyclononanetriyl group, cyclodecanetriyl group , Cyclododecanetriyl group, cyclohexadecanetriyl group and the like. As the alkanetetrayl group, cyclopropanetetrayl group, cyclobutanetetrayl group, cyclopentanetetrayl group, cyclohexanetetrayl group, cycloheptanetetrayl group, cyclooctanetetrayl group, cyclononanetetrayl group, cyclodecanetetrayl group Group, cyclododecanetetrayl group, cyclohexadecanetetrayl group and the like. These alicyclic groups may be substituted. Examples of the substituent include an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 15 carbon atoms, a halogen atom, a nitro group, an amide group, a hydroxyl group, an ester group, an ether group, and an aldehyde group.

  As an aromatic group, each of which contains a hetero atom and may have a heterocyclic structure, an arylene group having 5 to 15 carbon atoms, an arenetriyl group having 5 to 15 carbon atoms, an arenetetra having 5 to 15 carbon atoms Yl group. Examples of the arylene group include a phenylene group and a naphthalenediyl group. Examples of the arenetriyl group (trivalent) include a benzenetriyl group and a naphthalenetriyl group. Examples of the arenetetrayl group (tetravalent) include a benzenetetrayl group and a naphthalenetetrayl group. These aromatic groups may be substituted. Examples of the substituent include an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 15 carbon atoms, a halogen atom, a nitro group, an amide group, a hydroxyl group, an ester group, an ether group, and an aldehyde group.

In the formulas (1-1) and (1-2), s and k are integers of 0 to 10, preferably 0 to 3, more preferably 0 to 1. When s and k exceed 10, the cyclic carbodiimide compound is difficult to synthesize, and the cost may increase significantly. From this viewpoint, the integer is preferably selected in the range of 0 to 3. When s or k is 2 or more, X ¹ or X ² as a repeating unit may be different from other X ¹ or X ² .

X ³ is a divalent to tetravalent C 1-20 aliphatic group, a divalent to tetravalent C 3-20 alicyclic group, each of which may contain a heteroatom and a substituent, A tetravalent aromatic group having 5 to 15 carbon atoms, or a combination thereof.

Examples of the aliphatic group include an alkylene group having 1 to 20 carbon atoms, an alkanetriyl group having 1 to 20 carbon atoms, and an alkanetetrayl group having 1 to 20 carbon atoms. Examples of the alkylene group include a methylene group, an ethylene group, a propylene group, a butylene group, a pentylene group, a hexylene group, a heptylene group, an octylene group, a nonylene group, a decylene group, a dodecylene group, and a hexadecylene group. As the alkanetriyl group, methanetriyl group, ethanetriyl group, propanetriyl group, butanetriyl group, pentanetriyl group, hexanetriyl group, heptanetriyl group, octanetriyl group, nonanetriyl group, decantriyl group, dodecantriyl group, Examples include a hexadecantriyl group. As alkanetetrayl group, methanetetrayl group, ethanetetrayl group, propanetetrayl group, butanetetrayl group, pentanetetrayl group, hexanetetrayl group, heptanetetrayl group, octanetetrayl group, nonanetetrayl group Decanetetrayl group, dodecanetetrayl group, hexadecanetetrayl group and the like. These aliphatic groups may contain a substituent, such as an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 15 carbon atoms, a halogen atom, a nitro group, an amide group, a hydroxyl group, or an ester group. , Ether group, aldehyde group and the like.

  Examples of the alicyclic group include a cycloalkylene group having 3 to 20 carbon atoms, a cycloalkanetriyl group having 3 to 20 carbon atoms, and a cycloalkanetetrayl group having 3 to 20 carbon atoms. Examples of the cycloalkylene group include a cyclopropylene group, a cyclobutylene group, a cyclopentylene group, a cyclohexylene group, a cycloheptylene group, a cyclooctylene group, a cyclononylene group, a cyclodecylene group, a cyclododecylene group, and a cyclohexadecylene group. As the alkanetriyl group, cyclopropanetriyl group, cyclobutanetriyl group, cyclopentanetriyl group, cyclohexanetriyl group, cycloheptanetriyl group, cyclooctanetriyl group, cyclononanetriyl group, cyclodecanetriyl group , Cyclododecanetriyl group, cyclohexadecanetriyl group and the like. As the alkanetetrayl group, cyclopropanetetrayl group, cyclobutanetetrayl group, cyclopentanetetrayl group, cyclohexanetetrayl group, cycloheptanetetrayl group, cyclooctanetetrayl group, cyclononanetetrayl group, cyclodecanetetrayl group Group, cyclododecanetetrayl group, cyclohexadecanetetrayl group and the like. These alicyclic groups may contain a substituent, such as an alkyl group having 1 to 20 carbon atoms, an arylene group having 6 to 15 carbon atoms, a halogen atom, a nitro group, an amide group, a hydroxyl group, and an ester. Group, ether group, aldehyde group and the like.

  As an aromatic group, each of which contains a hetero atom and may have a heterocyclic structure, an arylene group having 5 to 15 carbon atoms, an arenetriyl group having 5 to 15 carbon atoms, an arenetetra having 5 to 15 carbon atoms Yl group. Examples of the arylene group include a phenylene group and a naphthalenediyl group. Examples of the arenetriyl group (trivalent) include a benzenetriyl group and a naphthalenetriyl group. Examples of the arenetetrayl group (tetravalent) include a benzenetetrayl group and a naphthalenetetrayl group. These aromatic groups may be substituted. Examples of the substituent include an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 15 carbon atoms, a halogen atom, a nitro group, an amide group, a hydroxyl group, an ester group, an ether group, and an aldehyde group.

Ar ¹ , Ar ² , R ¹ , R ² , X ¹ , X ² and X ³ may contain a hetero atom, and when Q is a divalent linking group, Ar ¹ , Ar ² , R ¹ , R ² , X ¹ , X ² and X ³ are all divalent groups. When Q is a trivalent linking group, one of Ar ¹ , Ar ² , R ¹ , R ² , X ¹ , X ² and X ³ is a trivalent group. When Q is a tetravalent linking group, one of Ar ¹ , Ar ² , R ¹ , R ² , X ¹ , X ² and X ³ is a tetravalent group or two are trivalent It is a group.

  Examples of the cyclic carbodiimide used in the present invention include compounds represented by the following formulas (2) to (4).

<Cyclic carbodiimide (2)>

Wherein, _{Q a} is (2-1) is a divalent linking group represented by (2-2) or (2-3).

In the formula, Ar _a ¹ , Ar _a ² , R _a ¹ , R _a ² , X _a ¹ , X _a ² , X _a ³ , s and k are represented by formulas (1-1) to (1-3), respectively. Are the same as Ar ¹ , Ar ² , R ¹ , R ² , X ¹ , X ² , X ³ , s and k. However, these are all divalent.

Examples of the cyclic carbodiimide compound (2) include the following compounds.

<Cyclic carbodiimide (3)>

Wherein, _{Q b} is the following formula (3-1), a trivalent bonding group represented by (3-2) or (3-3).

In the formula, Ar _b ¹ , Ar _b ² , R _b ¹ , R _b ² , X _b ¹ , X _b ² , X _b ³ , s and k are respectively represented by the formulas (1-1) to (1-3). The same as Ar ¹ , Ar ² , R ¹ , R ² , X ¹ , X ² , X ³ , s and k. However, one of these is a trivalent group.

Y is, Ru atom, atomic group or polymer der. Y is a bonding portion, and a plurality of cyclic structures are bonded via Y to form a structure represented by the formula (3). Examples of the cyclic carbodiimide compound (3) include the following compounds.

<Cyclic carbodiimide (4)>

In the formula, Q _c is a tetravalent linking group represented by the following formula (4-1), (4-2) or (4-3). Z ¹ and Z ² are carriers that support a cyclic structure. Z ¹ and Z ² may be bonded to each other to form a cyclic structure.

Ar _c ¹ , Ar _c ² , R _c ¹ , R _c ² , X _c ¹ , X _c ² , X _c ³ , s and k are each Ar ^{1 in} formulas (1-1) to (1-3). , Ar ² , R ¹ , R ² , X ¹ , X ² , X ³ , s and k are the same. Provided that Ar _c ¹ , Ar _c ² , R _c ¹ , R _c ² , X _c ¹ , X _c ² and X _c ³ are one of which is a tetravalent group or two of which are trivalent It is a group.

Z ¹ and Z ² are each independently atom, is preferably an atomic group or a polymer. Z ¹ and Z ² are bonding portions, and a plurality of cyclic structures are bonded via Z ¹ and Z ² to form a structure represented by the formula (4).
Examples of the cyclic carbodiimide compound (4) include the following compounds.

<Method for producing cyclic carbodiimide compound>
The cyclic carbodiimide compound can be produced by a conventionally known method. For example, a method for producing an amine body via an isocyanate body, a method for producing an amine body via an isothiocyanate body, a method for producing an amine body via a triphenylphosphine body, a urea body from an amine body The method of manufacturing via a thiourea body, the method of manufacturing via a thiourea body, the method of manufacturing from a carboxylic acid body via an isocyanate body, the method of manufacturing a lactam body, etc. are mentioned.

  Moreover, the cyclic carbodiimide compound of this invention can be manufactured by combining the method described in the following literature, or changing or combining suitably according to the target compound.

Tetrahedron Letters, Vol. 34, no. 32, 515-5158, 1993.
Medium- and Large-Membered Rings from Bis (iminophosphoranes): An Efficient Preparation of Cyclic Carbidiimides, Pedro Molina et al.
Journal of Organic Chemistry, Vol. 61, no. 13, 4289-4299, 1996.
New Models for the Study of the Racemization Mechanism of Carbodiimides. Synthesis and Structure (X-ray Crystallography and 1H NMR) of Cyclic Carbodiimides, Pedro Molina et al.
Journal of Organic Chemistry, Vol. 43, No8, 1944-1946, 1978.
Macrocyclic Urea As Masked Isocynates, Henri Ulrich et al.
Journal of Organic Chemistry, Vol. 48, no. 10, 1694-1700, 1983.
Synthesis and Reactions of Cyclic Carbodiimides, R.A. Richter et al.
Journal of Organic Chemistry, Vol. 59, no. 24, 7306-7315, 1994.
A New And Affiliate Preparation of Cyclic Carbodiamids from Bis (iminophosphoranea) and the System Boc ₂ O / DMAP, Pedro Molina et al.

Depending on the compound to be produced, an appropriate production method may be employed. For example, (1) nitrophenol represented by the following formula (a-1), nitrophenol represented by the following formula (a-2), and A step of reacting a compound represented by the following formula (b) to obtain a nitro compound represented by the following formula (c);

(2) A step of reducing the obtained nitro body to obtain an amine body represented by the following formula (d);

(3) a step of reacting the obtained amine body with triphenylphosphine dibromide to obtain a triphenylphosphine body represented by the following formula (e); and

(4) After the obtained triphenylphosphine body is isocyanated in the reaction system and then directly decarboxylated, it can be suitably used as the cyclic carbodiimide compound used in the present invention.
(In the above formula, Ar ¹ and Ar ² are each independently an aromatic group optionally substituted with an alkyl group having 1 to 6 carbon atoms or a phenyl group. E ¹ and E ² are each independently a halogen atom. A group selected from the group consisting of an atom, a toluenesulfonyloxy group, a methanesulfonyloxy group, a benzenesulfonyloxy group, and a p-bromobenzenesulfonyloxy group, Ar ^a is a phenyl group, X is represented by the following formula (i -1) to (i-3).

  The polylactic acid resin composition of the present invention includes a thermoplastic resin other than polylactic acid, a stabilizer, a crystallization accelerator, a filler, a mold release agent, an antistatic agent, and a plasticizer within the scope not departing from the spirit of the present invention. And at least one selected from the group consisting of impact resistance stabilizers and the like.

<Thermoplastic resin>
If desired, the polylactic acid resin composition of the present invention can contain a thermoplastic resin other than polylactic acid. Examples of such thermoplastic resins include polyester resins other than polylactic acid resins, polyamide resins, polyacetal resins, polyolefin resins such as polyethylene resins and polypropylene resins, polystyrene resins, acrylic resins, polyurethane resins, chlorinated polyethylene resins, and chlorinated polypropylenes. Resin, aromatic and aliphatic polyketone resin, fluorine resin, polyphenylene sulfide resin, polyether ether ketone resin, polyimide resin, thermoplastic starch resin, AS resin, ABS resin, AES resin, ACS resin, polyvinyl chloride resin, Polyvinylidene chloride resin, vinyl ester resin, MS resin, polycarbonate resin, polyarylate resin, polysulfone resin, polyethersulfone resin, phenoxy resin, polyphenylene oxa De resins, poly-4-methylpentene-1, polyetherimide resin, cellulose acetate resin, and thermoplastic resins such as polyvinyl alcohol resins. Among them, a polyester resin other than polyacetal resin and polylactic acid resin, for example, selected from polyester resins such as PET (polyethylene terephthalate), PTT (polytrimethylene terephthalate), PBT (polybutylene terephthalate), PEN (polyethylene naphthalate), and polyamide resins. It is preferable to blend at least one kind.

By blending these resins, the surface properties, moldability, mechanical properties, durability, toughness and the like of the molded article made of the polylactic acid resin composition of the present invention can be made excellent.
The content of the thermoplastic resin is preferably 0.5 to 200 parts by weight, more preferably 1 to 100 parts by weight, still more preferably 3 to 70 parts by weight, and still more preferably 5 to 5 parts by weight per 100 parts by weight of polylactic acid. 50 parts by weight. By blending these resins, it is possible to obtain a polylactic acid resin composition having excellent characteristics and a molded product comprising the same.

<Stabilizer>
The polylactic acid resin composition of the present invention can contain a stabilizer. As a stabilizer, what is used for the stabilizer of a normal thermoplastic resin can be used. For example, an antioxidant, a light stabilizer, etc. can be mentioned. By blending these agents, a molded product having excellent mechanical properties, moldability, heat resistance and durability can be obtained.

  Examples of the antioxidant include hindered phenol compounds, hindered amine compounds, phosphite compounds, thioether compounds, and the like.

  Examples of hindered phenol compounds include n-octadecyl-3- (3 ′, 5′-di-tert-butyl-4′-hydroxyphenyl) -propionate, n-octadecyl-3- (3′-methyl-5 ′). -Tert-butyl-4'-hydroxyphenyl) -propionate, n-tetradecyl-3- (3 ', 5'-di-tert-butyl-4'-hydroxyphenyl) -propionate, 1,6-hexanediol-bis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) -propionate], 1,4-butanediol-bis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) -Propionate], 2,2'-methylene-bis (4-methyl-tert-butylphenol), triethylene glycol-bis 3- (3-tert-butyl-5-methyl-4-hydroxyphenyl) -propionate], tetrakis [methylene-3- (3 ′, 5′-di-tert-butyl-4-hydroxyphenyl) propionate] methane, 3,9-bis [2- {3- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionyloxy} -1,1-dimethylethyl] 2,4,8,10-tetraoxaspiro ( 5,5) Undecane and the like can be mentioned.

  As a hindered amine compound, N, N′-bis-3- (3 ′, 5′-di-tert-butyl-4′-hydroxyphenyl) propionylhexamethylenediamine, N, N′-tetramethylene-bis [3- (3′-Methyl-5′-tert-butyl-4′-hydroxyphenyl) propionyl] diamine, N, N′-bis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) -propionyl ] Hydrazine, N-salicyloyl-N'-salicylidenehydrazine, 3- (N-salicyloyl) amino-1,2,4-triazole, N, N'-bis [2- {3- (3,5-di -Tert-butyl-4-hydroxyphenyl) propionyloxy} ethyl] oxyamide and the like. Preferably, triethylene glycol-bis [3- (3-tert-butyl-5-methyl-4-hydroxyphenyl) -propionate] and tetrakis [methylene-3- (3 ′, 5′-di-tert-butyl) -4-hydroxyphenyl) propionate] methane and the like.

  As the phosphite compound, those in which at least one P—O bond is bonded to an aromatic group are preferable. Specifically, tris (2,6-di-tert-butylphenyl) phosphite, tetrakis ( 2,6-di-tert-butylphenyl) 4,4′-biphenylene phosphite, bis (2,6-di-tert-butyl-4-methylphenyl) pentaerythritol di-phosphite, 2,2-methylenebis (4,6-di-tert-butylphenyl) octyl phosphite, 4,4′-butylidene-bis (3-methyl-6-tert-butylphenyl-di-tridecyl) phosphite, 1,1,3-tris (2-methyl-4-ditridecyl phosphite-5-tert-butylphenyl) butane, tris (mixed mono and di-no Butylphenyl) phosphite, tris (nonylphenyl) phosphite, 4,4'-isopropylidene-bis (phenyl - dialkyl phosphite), and the like.

  Among them, tris (2,6-di-tert-butylphenyl) phosphite, 2,2-methylenebis (4,6-di-tert-butylphenyl) octyl phosphite, bis (2,6-di-tert-butyl) -4-Methylphenyl) pentaerythritol-diphosphite, tetrakis (2,6-di-tert-butylphenyl) 4,4′-biphenylene phosphite and the like can be preferably used.

  Specific examples of thioether compounds include dilauryl thiodipropionate, ditridecyl thiodipropionate, dimyristyl thiodipropionate, distearyl thiodipropionate, pentaerythritol-tetrakis (3-lauryl thiopropionate), Pentaerythritol-tetrakis (3-dodecylthiopropionate), pentaerythritol-tetrakis (3-octadecylthiopropionate), pentaerythritol tetrakis (3-myristylthiopropionate), pentaerythritol-tetrakis (3-stearylthio) Propionate) and the like.

  Specific examples of the light stabilizer include benzophenone compounds, benzotriazole compounds, aromatic benzoate compounds, oxalic acid anilide compounds, cyanoacrylate compounds, hindered amine compounds, and the like.

  Examples of the benzophenone compounds include benzophenone, 2,4-dihydroxybenzophenone, 2,2′-dihydroxybenzophenone, 2,2 ′, 4,4′-tetrahydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2,2 ′. -Dihydroxy-4,4'-dimethoxybenzophenone, 2,2'-dihydroxy-4,4'-dimethoxy-5-sulfobenzophenone, 2-hydroxy-4-octoxybenzophenone, 2-hydroxy-4-dodecyloxybenzophenone 2-hydroxy-4-octoxybenzophenone, 2-hydroxy-4-methoxy-5-sulfobenzophenone, 5-chloro-2-hydroxybenzophenone, 2-hydroxy-4-octoxybenzophenone, 2-hydroxy-4-methoxy -2 - carboxy benzophenone, 2-hydroxy-4- (2-hydroxy-3-methyl - acryloxy-isopropoxyphenyl) benzophenone.

  Examples of the benzotriazole compound include 2- (5-methyl-2-hydroxyphenyl) benzotriazole, 2- (3,5-di-tert-butyl-2-hydroxyphenyl) benzotriazole, 2- (3,5- Di-tert-amyl-2-hydroxyphenyl) benzotriazole, 2- (3 ′, 5′-di-tert-butyl-4′-methyl-2′-hydroxyphenyl) benzotriazole, 2- (3,5- Di-tert-amyl-2-hydroxyphenyl) -5-chlorobenzotriazole, 2- (5-tert-butyl-2-hydroxyphenyl) benzotriazole, 2- [2′-hydroxy-3 ′, 5′-bis (Α, α-Dimethylbenzyl) phenyl] benzotriazole, 2- [2′-hydroxy-3 ′, 5′-bis (α, α Dimethylbenzyl) phenyl] -2H- benzotriazole, 2- (4'-octoxy-2'-hydroxyphenyl) benzotriazole.

  Examples of the aromatic benzoate compounds include alkylphenyl salicylates such as p-tert-butylphenyl salicylate and p-octylphenyl salicylate.

  Examples of oxalic acid anilide compounds include 2-ethoxy-2′-ethyloxalic acid bisanilide, 2-ethoxy-5-tert-butyl-2′-ethyloxalic acid bisanilide, and 2-ethoxy-3′-. Examples include dodecyl oxalic acid bisanilide.

  Examples of the cyanoacrylate compound include ethyl-2-cyano-3,3'-diphenyl acrylate, 2-ethylhexyl-cyano-3,3'-diphenyl acrylate, and the like.

  Examples of hindered amine compounds include 4-acetoxy-2,2,6,6-tetramethylpiperidine, 4-stearoyloxy-2,2,6,6-tetramethylpiperidine, 4-acryloyloxy-2,2,6, 6-tetramethylpiperidine, 4- (phenylacetoxy) -2,2,6,6-tetramethylpiperidine, 4-benzoyloxy-2,2,6,6-tetramethylpiperidine, 4-methoxy-2,2, 6,6-tetramethylpiperidine, 4-octadecyloxy-2,2,6,6-tetramethylpiperidine, 4-cyclohexyloxy-2,2,6,6-tetramethylpiperidine, 4-benzyloxy-2,2 , 6,6-tetramethylpiperidine, 4-phenoxy-2,2,6,6-tetramethylpiperidine, 4- (ethylcarba Yloxy) -2,2,6,6-tetramethylpiperidine, 4- (cyclohexylcarbamoyloxy) -2,2,6,6-tetramethylpiperidine, 4- (phenylcarbamoyloxy) -2,2,6,6 -Tetramethylpiperidine, bis (2,2,6,6-tetramethyl-4-piperidyl) carbonate, bis (2,2,6,6-tetramethyl-4-piperidyl) oxalate, bis (2,2,6 , 6-tetramethyl-4-piperidyl) malonate, bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate, bis (2,2,6,6-tetramethylpi-4-peridyl) adipate, bis (2,2,6,6-tetramethylpi-4-peridyl) terephthalate, 1,2-bis (2,2,6,6-tetramethylpi-4-peridylo) Cis) -ethane, α, α′-bis (2,2,6,6-tetramethyl-4-piperidyloxy) -p-xylene, bis (2,2,6,6-tetramethyl-4-piperidyl) -Tolylene-2,4-dicarbamate, bis (2,2,6,6-tetramethyl-4-piperidyl) -hexamethylene-1,6-dicarbamate, tris (2,2,6,6-tetramethyl -4-piperidyl) -benzene-1,3,5-tricarboxylate, tris (2,2,6,6-tetramethyl-4-piperidyl) -benzene-1,3,4-tricarboxylate, 1- “2- {3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionyloxy} -2,2,6,6-tetramethylpiperidine, 1,2,3,4-butanetetracarboxylic acid And 1,2,2, , 6-Pentamethyl-4-piperidinol and β, β, β ′, β′-tetramethyl-3,9- [2,4,8,10-tetraoxaspiro (5,5) undecane] dimethanol And the like. In this invention, E component may be used by 1 type and may be used in combination of 2 or more type. As the stabilizer component, a hindered phenol compound and / or a benzotriazole compound are preferable. The content of the stabilizer is preferably 0.01 to 3 parts by weight, more preferably 0.03 to 2 parts by weight, per 100 parts by weight of the stereocomplex polylactic acid.

<Crystallization accelerator>
The polylactic acid resin composition of the present invention can contain an organic or inorganic crystallization accelerator. The formation of stereocomplex polylactic acid crystals of the polylactic acid resin composition is promoted by containing a crystallization accelerator. That is, the effect of improving the heat resistance of the polylactic acid resin by the phosphate ester metal salt can be further enhanced, and a molded product having excellent mechanical properties, heat resistance, and moldability can be obtained. In addition, the manufacturing time for manufacturing the molded product can be greatly shortened, and the economic effect is great.

  As the crystallization accelerator used in the present invention, those generally used as crystallization nucleating agents for crystalline resins can be used, and both inorganic crystallization nucleating agents and organic crystallization nucleating agents are used. be able to.

  As inorganic crystallization nucleating agents, talc, kaolin, silica, synthetic mica, clay, zeolite, graphite, carbon black, zinc oxide, magnesium oxide, titanium oxide, calcium carbonate, calcium sulfate, barium sulfate, calcium sulfide, boron nitride , Montmorillonite, neodymium oxide, aluminum oxide, phenylphosphonate metal salt and the like. These inorganic crystallization nucleating agents are treated with various dispersing aids in order to enhance the dispersibility in the polylactic acid resin composition and the effect thereof, and have a high primary particle size of about 0.01 to 0.5 μm. Those in a dispersed state are preferred.

  Organic crystallization nucleating agents include calcium benzoate, sodium benzoate, lithium benzoate, potassium benzoate, magnesium benzoate, barium benzoate, calcium oxalate, disodium terephthalate, dilithium terephthalate, dipotassium terephthalate, Sodium laurate, potassium laurate, sodium myristate, potassium myristate, calcium myristate, barium myristate, sodium octacolate, calcium octacolate, sodium stearate, potassium stearate, lithium stearate, calcium stearate, magnesium stearate , Barium stearate, sodium montanate, calcium montanate, sodium toluate, sodium salicylate, potassium salicylate, salicy Organic carboxylic acid metal salts such as zinc acid, aluminum dibenzoate, β-naphthoic acid sodium, β-naphthoic acid potassium, sodium cyclohexanecarboxylic acid and the like, and organic sulfonic acid metal salts such as sodium p-toluenesulfonate and sodium sulfoisophthalate. Can be mentioned.

  Also, organic carboxylic acid amides such as stearic acid amide, ethylenebislauric acid amide, palmitic acid amide, hydroxystearic acid amide, erucic acid amide, trimesic acid tris (tert-butylamide), low density polyethylene, high density polyethylene, polyiso Propylene, polybutene, poly-4-methylpentene, poly-3-methylbutene-1, polyvinylcycloalkane, polyvinyltrialkylsilane, high melting point polylactic acid, sodium salt of ethylene-acrylic acid copolymer, sodium of styrene-maleic anhydride copolymer Examples thereof include salts (so-called ionomers), benzylidene sorbitol and derivatives thereof such as dibenzylidene sorbitol.

Among these, at least one selected from talc and organic carboxylic acid metal salts is preferably used. Only one type of crystallization accelerator may be used in the present invention, or two or more types may be used in combination.
The content of the crystallization accelerator is preferably 0.01 to 30 parts by weight, more preferably 0.05 to 20 parts by weight per 100 parts by weight of the stereocomplex polylactic acid.

<Filler>
The polylactic acid resin composition of the present invention can contain an organic or inorganic filler. By containing the filler component, a molded product having excellent mechanical properties, heat resistance, and moldability can be obtained.

  Organic fillers such as rice husks, wood chips, okara, waste paper ground materials, clothing ground materials, cotton fibers, hemp fibers, bamboo fibers, wood fibers, kenaf fibers, jute fibers, banana fibers, coconut fibers Plant fibers such as pulp or cellulose fibers processed from these plant fibers and fibrous fibers such as animal fibers such as silk, wool, angora, cashmere and camel, synthetic fibers such as polyester fibers, nylon fibers and acrylic fibers , Paper powder, wood powder, cellulose powder, rice husk powder, fruit husk powder, chitin powder, chitosan powder, protein, starch and the like. From the viewpoint of moldability, powdery materials such as paper powder, wood powder, bamboo powder, cellulose powder, kenaf powder, rice husk powder, fruit husk powder, chitin powder, chitosan powder, protein powder, and starch are preferred. Powder, bamboo powder, cellulose powder and kenaf powder are preferred. Paper powder and wood powder are more preferable. Paper dust is particularly preferable.

These organic fillers may be those directly collected from natural products, but may also be those obtained by recycling waste materials such as waste paper, waste wood and old clothes.
The wood is preferably a softwood material such as pine, cedar, oak or fir, or a hardwood material such as beech, shii or eucalyptus.

  Paper powder is an adhesive from the viewpoint of moldability, especially emulsion adhesives such as vinyl acetate resin emulsions and acrylic resin emulsions that are usually used when processing paper, polyvinyl alcohol adhesives, polyamide adhesives Those containing hot melt adhesives such as are preferably exemplified.

  In the present invention, the blending amount of the organic filler is not particularly limited, but from the viewpoint of moldability and heat resistance, it is preferably 1 to 300 parts by weight, more preferably 5 to 5 parts per 100 parts by weight of the stereocomplex polylactic acid. 200 parts by weight, more preferably 10 to 150 parts by weight, particularly preferably 15 to 100 parts by weight. If the blending amount of the organic filler is less than 1 part by weight, the effect of improving the moldability of the polylactic acid resin composition is small, and if it exceeds 300 parts by weight, uniform dispersion of the filler becomes difficult, or moldability, In addition to heat resistance, the strength and appearance of the material may decrease, which is not preferable.

  The polylactic acid resin composition of the present invention preferably contains an inorganic filler. By using the inorganic filler, a polylactic acid resin composition having excellent mechanical properties, heat resistance, and moldability can be obtained. As the inorganic filler used in the present invention, a fibrous, plate-like, or powder-like material used for reinforcing ordinary thermoplastic resins can be used.

  Specifically, for example, carbon nanotube, glass fiber, asbestos fiber, carbon fiber, graphite fiber, metal fiber, potassium titanate whisker, aluminum borate whisker, magnesium whisker, silicon whisker, wollastonite, imogolite, sepiolite, Asbestos, slag fiber, zonolite, gypsum fiber, silica fiber, silica-alumina fiber, zirconia fiber, boron nitride fiber, silicon nitride fiber, boron fiber, and other fibrous inorganic fillers, layered silicate, and organic onium ions Layered silicate, glass flake, non-swelling mica, graphite, metal foil, ceramic beads, talc, clay, mica, sericite, zeolite, bentonite, dolomite, kaolin, powdered silicic acid, feldspar powder, potassium titanate, shirasuba Plates and particles of inorganic fillers such as carbon nanoparticles such as carbon, calcium carbonate, magnesium carbonate, barium sulfate, calcium oxide, aluminum oxide, titanium oxide, aluminum silicate, silicon oxide, gypsum, novaculite, dosonite and white clay fullerene Agents.

  Specific examples of layered silicates include smectite clay minerals such as montmorillonite, beidellite, nontronite, saponite, hectorite, and soconite, various clay minerals such as vermiculite, halosite, kanemite, and kenyanite, Li-type fluorine teniolite, Na And swellable mica such as Li-type fluorine teniolite, Li-type tetrasilicon fluorine mica and Na-type tetrasilicon fluorine mica. These may be natural or synthetic. Among these, smectite clay minerals such as montmorillonite and hectorite, and swellable synthetic mica such as Li type fluorine teniolite and Na type tetrasilicon fluorine mica are preferable.

  Among these inorganic fillers, fibrous or plate-like inorganic fillers are preferable, and glass fiber, wollastonite, aluminum borate whisker, potassium titanate whisker, mica, and kaolin, a cation-exchanged layered silicate. Is preferred. The aspect ratio of the fibrous filler is preferably 5 or more, more preferably 10 or more, and further preferably 20 or more.

  Such a filler may be coated or converged with a thermoplastic resin such as an ethylene / vinyl acetate copolymer or a thermosetting resin such as an epoxy resin, or may be treated with a coupling agent such as aminosilane or epoxysilane. May be.

  The amount of the inorganic filler is preferably 0.1 to 200 parts by weight, more preferably 0.5 to 100 parts by weight, still more preferably 1 to 50 parts by weight, particularly preferably 100 parts by weight of the stereocomplex polylactic acid. Is 1-30 parts by weight, most preferably 1-20 parts by weight.

<Release agent>
The polylactic acid resin composition of the present invention can contain a release agent. As the mold release agent used in the present invention, those used for ordinary thermoplastic resins can be used.
Specific examples of release agents include fatty acids, fatty acid metal salts, oxy fatty acids, paraffins, low molecular weight polyolefins, fatty acid amides, alkylene bis fatty acid amides, aliphatic ketones, fatty acid partial saponified esters, fatty acid lower alcohol esters, fatty acid polyvalents. Examples include alcohol esters, fatty acid polyglycol esters, and modified silicones. By blending these, a polylactic acid molded product excellent in mechanical properties, moldability, and heat resistance can be obtained.

  Fatty acids having 6 to 40 carbon atoms are preferred. Specifically, oleic acid, stearic acid, lauric acid, hydroxystearic acid, behenic acid, arachidonic acid, linoleic acid, linolenic acid, ricinoleic acid, palmitic acid, montan Examples thereof include acids and mixtures thereof. The fatty acid metal salt is preferably an alkali metal salt or alkaline earth metal salt of a fatty acid having 6 to 40 carbon atoms, and specific examples include calcium stearate, sodium montanate, calcium montanate, and the like.

  Examples of the oxy fatty acid include 1,2-oxysteric acid. Paraffin having 18 or more carbon atoms is preferable, and examples thereof include liquid paraffin, natural paraffin, microcrystalline wax, petrolactam and the like.

  As the low molecular weight polyolefin, for example, those having a molecular weight of 5000 or less are preferable, and specific examples include polyethylene wax, maleic acid-modified polyethylene wax, oxidized type polyethylene wax, chlorinated polyethylene wax, and polypropylene wax. Fatty acid amides having 6 or more carbon atoms are preferred, and specific examples include oleic acid amide, erucic acid amide, and behenic acid amide.

  The alkylene bis fatty acid amide is preferably one having 6 or more carbon atoms, and specifically includes methylene bis stearic acid amide, ethylene bis stearic acid amide, N, N-bis (2-hydroxyethyl) stearic acid amide and the like. As the aliphatic ketone, those having 6 or more carbon atoms are preferable, and examples thereof include higher aliphatic ketones.

  Examples of the fatty acid partial saponified ester include a montanic acid partial saponified ester. Examples of the fatty acid lower alcohol ester include stearic acid ester, oleic acid ester, linoleic acid ester, linolenic acid ester, adipic acid ester, behenic acid ester, arachidonic acid ester, montanic acid ester, isostearic acid ester and the like.

  Examples of fatty acid polyhydric alcohol esters include glycerol tristearate, glycerol distearate, glycerol monostearate, pentaerythritol tetrastearate, pentaerythritol tristearate, pentaerythritol dimyristate, pentaerythritol Examples include tall monostearate, pentaerythritol adipate stearate, sorbitan monobehenate and the like. Examples of fatty acid polyglycol esters include polyethylene glycol fatty acid esters and polypropylene glycol fatty acid esters.

  Examples of the modified silicone include polyether-modified silicone, higher fatty acid alkoxy-modified silicone, higher fatty acid-containing silicone, higher fatty acid ester-modified silicone, methacryl-modified silicone, and fluorine-modified silicone.

  Of these, fatty acid, fatty acid metal salt, oxy fatty acid, fatty acid ester, fatty acid partial saponified ester, paraffin, low molecular weight polyolefin, fatty acid amide, and alkylene bis fatty acid amide are preferred, and fatty acid partial saponified ester and alkylene bis fatty acid amide are more preferred. Of these, montanic acid ester, montanic acid partial saponified ester, polyethylene wax, acid value polyethylene wax, sorbitan fatty acid ester, erucic acid amide, and ethylene bisstearic acid amide are preferred, and particularly, montanic acid partial saponified ester and ethylene bisstearic acid amide are preferred. preferable.

  A mold release agent may be used by 1 type and may be used in combination of 2 or more type. The content of the release agent is preferably 0.01 to 3 parts by weight, more preferably 0.03 to 2 parts by weight, with respect to 100 parts by weight of the stereocomplex polylactic acid.

<Antistatic agent>
The polylactic acid resin composition of the present invention can contain an antistatic agent. Examples of the antistatic agent include quaternary ammonium salt compounds such as (β-lauramidopropionyl) trimethylammonium sulfate and sodium dodecylbenzenesulfonate, sulfonate compounds, and alkyl phosphate compounds.

  In the present invention, the antistatic agent may be used alone or in combination of two or more. The content of the antistatic agent is preferably 0.05 to 5 parts by weight, more preferably 0.1 to 5 parts by weight with respect to 100 parts by weight of the stereocomplex polylactic acid.

<Plasticizer>
The polylactic acid resin composition of the present invention can contain a plasticizer. As the plasticizer, generally known plasticizers can be used. Examples include polyester plasticizers, glycerin plasticizers, polycarboxylic acid ester plasticizers, phosphate ester plasticizers, polyalkylene glycol plasticizers, and epoxy plasticizers.

  As a polyester plasticizer, acid components such as adipic acid, sebacic acid, terephthalic acid, isophthalic acid, naphthalenedicarboxylic acid, diphenyldicarboxylic acid and ethylene glycol, propylene glycol, 1,3-butanediol, 1,4-butanediol, Examples thereof include polyesters composed of diol components such as 1,6-hexanediol and diethylene glycol, and polyesters composed of hydroxycarboxylic acids such as polycaprolactone. These polyesters may be end-group-capped with a monofunctional carboxylic acid or a monofunctional alcohol.

  Examples of the glycerol plasticizer include glycerol monostearate, glycerol distearate, glycerol monoacetomonolaurate, glycerol monoacetomonostearate, glycerol diacetomonooleate, and glycerol monoacetomonomontanate.

  Polyvalent carboxylic acid plasticizers include dimethyl phthalate, diethyl phthalate, dibutyl phthalate, diheptyl phthalate, dibenzyl phthalate, butyl benzyl phthalate, trimellitic acid tributyl, trimellitic acid trioctyl, Trimellitic acid esters such as trihexyl meritate, isodecyl adipate, adipic acid esters such as adipate-n-decyl-n-octyl, citrate esters such as tributyl acetylcitrate, and bis (2-ethylhexyl) azelate Examples include sebacic acid esters such as azelaic acid ester, dibutyl sebacate, and bis (2-ethylhexyl) sebacate.

  Examples of the phosphate ester plasticizer include tributyl phosphate, tris phosphate (2-ethylhexyl), trioctyl phosphate, triphenyl phosphate, tricresyl phosphate, diphenyl-2-ethylhexyl phosphate, and the like.

  Polyalkylene glycol plasticizers such as polyethylene glycol, polypropylene glycol, polytetramethylene glycol, poly (ethylene oxide-propylene oxide) block and / or random copolymers, ethylene oxide addition polymers of bisphenols, tetrahydrofuran addition polymers of bisphenols, etc. And a terminal group sealing compound such as a terminal group epoxy-modified compound, a terminal group ester-modified compound, and a terminal group ether-modified compound.

  Examples of the epoxy plasticizer include an epoxy triglyceride composed of alkyl epoxy stearate and soybean oil, and an epoxy resin using bisphenol A and epichlorohydrin as raw materials.

  Specific examples of other plasticizers include benzoic acid esters of aliphatic polyols such as neopentyl glycol dibenzoate, diethylene glycol dibenzoate, triethylene glycol-bis (2-ethylbutyrate), and fatty acids such as stearamide. Examples thereof include fatty acid esters such as amide and butyl oleate, oxyacid esters such as methyl acetylricinoleate and butyl acetylricinoleate, pentaerythritol, various sorbitols, polyacrylic acid esters, silicone oils, and paraffins.

  As the plasticizer, at least one selected from polyester-type plasticizers and polyalkylene-type plasticizers can be preferably used, and only one type may be used, or two or more types may be used in combination.

  The content of the plasticizer is preferably 0.01 to 30 parts by weight, more preferably 0.05 to 20 parts by weight, and still more preferably 0.1 to 10 parts by weight per 100 parts by weight of the stereocomplex polylactic acid. In the present invention, each of the crystallization nucleating agent and the plasticizer may be used alone, or more preferably used in combination.

<Impact resistance improver>
The polylactic acid resin composition of the present invention can contain an impact resistance improver. The impact resistance improver is one that can be used to improve the impact resistance of a thermoplastic resin, and is not particularly limited. For example, at least one selected from the following impact resistance improvers can be used.

  Specific examples of impact modifiers include ethylene-propylene copolymers, ethylene-propylene-nonconjugated diene copolymers, ethylene-butene-1 copolymers, various acrylic rubbers, ethylene-acrylic acid copolymers and their Alkali metal salts (so-called ionomers), ethylene-glycidyl (meth) acrylate copolymers, ethylene-acrylate copolymers (for example, ethylene-ethyl acrylate copolymers, ethylene-butyl acrylate copolymers), modified ethylene -Propylene copolymer, diene rubber (eg polybutadiene, polyisoprene, polychloroprene), diene and vinyl copolymer (eg styrene-butadiene random copolymer, styrene-butadiene block copolymer, styrene-butadiene-styrene block copolymer) Coalescence, styrene Soprene random copolymer, styrene-isoprene block copolymer, styrene-isoprene-styrene block copolymer, polybutadiene graft copolymerized with styrene, butadiene-acrylonitrile copolymer), polyisobutylene, isobutylene and butadiene Or a copolymer with isoprene, natural rubber, thiocol rubber, polysulfide rubber, polyurethane rubber, polyether rubber, epichlorohydrin rubber and the like can be mentioned.

  In addition, those having various cross-linking degrees, various micro structures such as those having a cis structure, a trans structure, etc., a core layer and one or more shell layers covering the core layer, and adjacent layers are composed of heterogeneous polymers. A so-called core-shell type multi-layered polymer can also be used.

  Furthermore, the various (co) polymers mentioned in the above specific examples may be any of random copolymers, block copolymers, block copolymers and the like, and can be used as the impact resistance improver of the present invention.

  The impact resistance improver is preferably 1 to 30 parts by weight, more preferably 5 to 20 parts by weight, and still more preferably 10 to 20 parts by weight with respect to 100 parts by weight of the stereocomplex polylactic acid.

<Others>
Further, the polylactic acid resin composition of the present invention may contain a thermosetting resin such as a phenol resin, a melamine resin, a thermosetting polyester resin, a silicone resin, and an epoxy resin within a range not departing from the spirit of the present invention. . In addition, the polylactic acid resin composition of the present invention may contain a flame retardant such as bromine, phosphorus, silicone, and antimony compound as long as it does not contradict the spirit of the present invention. Colorants containing organic and inorganic dyes and pigments, for example, oxides such as titanium dioxide, hydroxides such as alumina white, sulfides such as zinc sulfide, ferrocyanides such as bitumen, and chromium such as zinc chromate Contains acid salts, sulfates such as barium sulfate, carbonates such as calcium carbonate, silicates such as ultramarine, phosphates such as manganese violet, carbon such as carbon black, metal colorants such as bronze powder and aluminum powder, etc. You may let them. Also, nitroso type such as naphthol green B, nitro type such as naphthol yellow S, azo type such as naphthol red and chromophthal yellow, phthalocyanine type such as phthalocyanine blue and fast sky blue, and condensed polycyclic coloring such as indanthrone blue An additive such as a slidability improver such as a graphite or fluorine resin may be added. These additives can be used alone or in combination of two or more.

A polylactic acid resin composition containing these additives can be prepared by mixing the respective components. For the mixing, a tumbler, a V-type blender, a super mixer, a nauter mixer, a Banbury mixer, a kneading roll, a monoaxial or biaxial extruder can be used. The resulting polylactic acid resin composition can be molded as it is or after being once pelletized with a melt extruder.
The reduced viscosity retention ratio (ηR) of the polylactic acid resin composition of the present invention is 70% or more, preferably 80% or more, more preferably 85% or more.

<Molded product>
The polylactic acid resin composition of the present invention can be used as a molded product by injection molding, extrusion molding, vacuum, pressure molding, blow molding or the like. Examples of the molded article include pellets, fibers, fabrics, fiber structures, films, sheets, and sheet nonwoven fabrics.

  The pellet made of the polylactic acid resin composition of the present invention is not limited in its melt molding method, and those produced by a known pellet production method can be suitably used. That is, a polylactic acid resin composition extruded into a strand or a plate is formed in air or underwater after the polylactic acid resin composition is completely solidified or not completely solidified and still in a molten state. Conventionally known methods such as cutting with the method are known, but any of them can be suitably applied in the present invention.

  The shape of the pellet may be any shape such as a spherical shape, a die shape, a linear shape, a curved shape, and a cross-sectional shape such as a round shape, an oval shape, a flat shape, a triangular shape, a polygon shape having a square shape or more, and a star shape. However, it is preferable to have a shape suitable for further molding the pellets by various molding methods. Specifically, the pellet length is preferably 1 to 7 mm, the major axis is 3 to 5 mm, and the minor axis is 1 to 4 mm. Further, it is preferable that the shape does not vary.

  In the injection molding of the present invention, the molding conditions may be set as appropriate. From the viewpoint of increasing the crystallization of the molded product and the molding cycle during injection molding, the mold temperature is preferably 30 ° C. or higher, more preferably 60 ° C. or higher. More preferably, it is 70 ° C. or higher. However, in order to prevent deformation of the molded product, the mold temperature is preferably 140 ° C. or lower, more preferably 120 ° C. or lower, and further preferably 110 ° C. or lower.

  Examples of these molded products include various housings, electric / electronic parts such as gears and gears, building members, civil engineering members, agricultural materials, automobile parts (interior parts, exterior parts, etc.), and daily parts.

  The polylactic acid resin composition of the present invention can be suitably used as a material for fibers and fiber structures. For these fibers and fiber structures, materials obtained by ordinary melt spinning and subsequent post-processing can be preferably used.

  That is, the polylactic acid resin composition of the present invention is melted by an extruder type or pressure melter type melt extruder, measured by a gear pump, filtered in a pack, and then monofilament from a nozzle provided in the base, It is discharged as a multifilament or the like.

  The shape of the base and the number of the bases are not particularly limited, and any of circular, irregular, solid, hollow and the like can be adopted. The discharged yarn is immediately cooled and solidified, then converged, applied with oil, and wound. The winding speed is not particularly limited, but a range of 300 m / min to 5,000 m / min is preferable because a stereo complex crystal is easily formed.

  From the viewpoint of stretchability, a winding speed at which the stereocomplex crystallization ratio (Sc) of the undrawn yarn is 0% is preferable. The undrawn yarn that has been wound is then subjected to a drawing step, but the spinning step and the drawing step do not necessarily need to be separated, and even if a direct spinning drawing method is used in which the drawing is continued without being wound once after spinning. I do not care.

  The stretching may be one-stage stretching or multi-stage stretching of two or more stages. From the viewpoint of producing a high-strength fiber, the stretching ratio is preferably 3 times or more, and more preferably 4 times or more. Preferably 3 to 10 times is selected. However, if the draw ratio is too high, the fiber is devitrified and whitened, the strength of the fiber is lowered, the elongation at break is too low, and it is not preferable for fiber use.

  As a preheating method for stretching, in addition to the temperature rise of the roll, a flat or pin-like contact heater, a non-contact hot plate, a heat medium bath, and the like can be used, and a commonly used method may be used.

  Subsequent to stretching, it is preferable that heat treatment is performed at a temperature not lower than the melting point of the glass transition temperature (Tg) of the stereocomplex polylactic acid before winding. In addition to the hot roller, any method such as a contact heater or a non-contact hot plate can be adopted for the heat treatment. For example, the stretching temperature is selected from the glass transition temperature (Tg) to 170 ° C., preferably 70 ° C. to 140 ° C., particularly preferably 80 to 130 ° C.

  In addition, after stretching, it is heat-set at 170 ° C. to 220 ° C. under tension, so that it has a high stereocomplex crystallization rate (Sc), low heat shrinkage, and a stereocomplex polylactic acid fiber having a strength of 3.5 cN / dTex or more. You can also get

  The fibers obtained from the polylactic acid resin composition of the present invention can take various fiber structure forms. Specifically, thread form products such as sewing thread, embroidery thread, string, fabric such as woven fabric, knitted fabric, nonwoven fabric, felt, outer clothing such as shirt, blouson, pants, coat, sweater, uniform, underwear, pantyhose, socks, Lining, interlining, sports clothing, high value-added clothing products such as women's clothing and formal wear, clothing products such as cups and pads, curtains, carpets, chair upholstery, mats, furniture, baskets, furniture upholstery, wall materials, etc. Products for daily use such as belts and slings, as well as various textile products such as canvas, belts, nets, ropes, heavy cloth, bags, industrial materials such as felts and filters, vehicle interior products, and artificial leather products.

  The fiber and fiber structure made of the polylactic acid resin composition of the present invention may be used alone or in combination with other types of fibers. In addition to various combinations with fiber structures composed of other types of fibers, mixed modes include mixed yarns with other fibers, composite false twisted yarns, mixed spun yarns, long and short composite yarns, fluid processed yarns, covering yarns, and twisted yarns. Examples thereof include union, union, pile, pile, mixed cotton, mixed non-woven fabric of long fibers and short fibers, and felt. When mixed, in order to exhibit the characteristics of stereocomplex polylactic acid, the mixed ratio is selected from the range of 1% by weight or more, more preferably 10% by weight or more, and further preferably 30% by weight or more.

  Examples of other fibers to be mixed include cellulose fibers such as cotton, hemp, rayon, and tencel, wool, silk, acetate, polyester, nylon, acrylic, vinylon, polyolefin, and polyurethane.

  In addition, the polylactic acid resin composition of the present invention can be used after being formed into a film or sheet by a conventionally known method. In forming a film or sheet, for example, a molding technique such as extrusion molding or cast molding can be used. That is, an unstretched film is extruded using an extruder or the like equipped with a T die, a circular die or the like, and further stretched and heat-treated to form. At this time, the unstretched film can be used as it is as a sheet. In forming the film, a material obtained by melt-kneading the polylactic acid resin composition and the above-described various components in advance can be used, or the material can be formed through melt-kneading during extrusion molding. When extruding an unstretched film, an unstretched film with few surface defects can be obtained by blending a molten resin with an electrostatic adhesive such as a sulfonic acid quaternary phosphonium salt.

  Moreover, an unstretched film can also be cast-molded by melt | dissolving, casting, and drying and solidifying a polylactic acid resin composition and an additive component using solvents, such as chloroform and a methylene dichloride, for example.

  Unstretched film can be uniaxially stretched longitudinally in the direction of mechanical flow and transversely uniaxially stretched in the direction perpendicular to the direction of mechanical flow. Also, the biaxial stretching method of roll stretching and tenter stretching, and simultaneous biaxial stretching by tenter stretching A biaxially stretched film can be produced by stretching by a biaxial stretching method using a method such as tubular stretching. Further, the film is usually subjected to a heat setting treatment after stretching in order to suppress heat shrinkability and the like. The stretched film thus obtained can be subjected to surface activation treatment such as plasma treatment, amine treatment, and corona treatment by a conventionally known method if desired.

  The film and sheet of the present invention can be used in combination with other types of films and sheets other than a single form. Examples of mixed use include various combinations with films and sheets made of other types of materials, such as lamination and lamination, and combinations with other types of forms such as injection molded articles and fiber structures.

  EXAMPLES Hereinafter, although an Example demonstrates this invention concretely, this invention does not receive any limitation by this. In the examples, various characteristics were determined by the following methods.

(1) Weight average molecular weight (Mw) and number average molecular weight (Mn) of the polymer:
The weight average molecular weight and number average molecular weight of the polymer were measured by gel permeation chromatography (GPC) and converted to standard polystyrene. GPC measuring instrument is detector; differential refractometer (manufactured by Shimadzu Corporation) RID-6A column; Toso-Co., Ltd. TSKgel G3000HXL, TSKgel G4000HXL, TSKgel G5000HXL and TSKguardcocumHXL-L TSKgel G2000HXL, TSKgelG3000HXL, and TSKguardcocumHXL-L connected in series were used.
Chloroform was used as an eluent, 10 μl of a sample having a concentration of 1 mg / ml (chloroform containing 1% hexafluoroisopropanol) was injected at a temperature of 40 ° C. and a flow rate of 1.0 ml / min.

(2) Carboxyl group concentration: The sample was dissolved in purified o-cresol under a nitrogen stream and titrated with 0.05 N potassium hydroxide in ethanol using bromocresol blue as an indicator.

(3) DSC measurement of stereocomplex crystallinity [S (%)], crystal melting temperature, etc .:
Using DSC (TA Instrument, TA-2920), the sample was heated to 250 ° C. at 10 ° C./min under a nitrogen stream in the first cycle, and the glass transition temperature (Tg), stereocomplex phase poly Lactic acid crystal melting temperature (Tm *), stereocomplex phase polylactic acid crystal melting enthalpy (ΔHms) and homophase polylactic acid crystal melting enthalpy (ΔHmh) were measured.
In addition, the crystallization start temperature (Tc *) and the crystallization temperature (Tc) were measured by rapidly cooling the measurement sample and then performing a second cycle measurement under the same conditions. The stereocomplex crystallinity is a value obtained by the following formula (ii) from the stereocomplex phase and homophase polylactic acid crystal melting enthalpy obtained by the above measurement.
S = [ΔHms / (ΔHmh + ΔHms)] × 100 (ii)
(However, ΔHms is the melting enthalpy of stereocomplex phase crystals, ΔHmh is the melting enthalpy of homophase polylactic acid crystals)

(4) Identification of cyclic carbodiimide structure by NMR and determination of cyclic carbodiimide in polylactic acid resin composition:
The synthesized cyclic carbodiimide compound was confirmed by ¹ H-NMR and ¹³ C-NMR. For NMR, JNR-EX270 manufactured by JEOL Ltd. was used. Deuterated chloroform was used as the solvent.

(5) Identification of carbodiimide skeleton of cyclic carbodiimide by IR:
The presence or absence of the carbodiimide skeleton of the synthesized cyclic carbodiimide compound was confirmed by FT-IR at 2100-2200 cm ⁻¹ characteristic of carbodiimide. For FT-IR, Magna-750 manufactured by Thermo Nicolay Co., Ltd. was used.

(6) Stability against hydrolysis:
Regarding the aliphatic polyester, the reduced viscosity retention rate was evaluated when the sample was treated with a constant temperature and humidity machine at 80 ° C. and 95% RH for 100 hours.
Moreover, about the aromatic polyester, the reduced viscosity retention was evaluated when the sample was treated with a pressure cooker at 120 ° C. and 100% RH for 50 hours.
The hydrolysis resistance stability of the polylactic acid resin composition is “pass” when the reduced viscosity retention is 80 to less than 90%, “excellent pass” when it is less than 90% to 95%, and 95% to 100%. Sometimes judged to be “especially an excellent pass”.
The reduced viscosity (η _sp / c) was measured by dissolving 1.2 mg of a sample in 100 ml of [tetrachloroethane / phenol = (6/4) wt% mixed solvent] and measuring at 35 ° C. using an Ubbelohde viscosity tube. Viscosity retention was determined as the reduced viscosity after sample treatment for the molecule and the reduced viscosity before sample treatment for the denominator.

(7) Existence of isocyanate odor:
When the sample was melted at 260 ° C. for 5 minutes, it was determined by sensory evaluation whether or not the measurer felt an isocyanate odor. When the isocyanate odor was not felt, it was judged to be acceptable.

(8) Good working environment:
At the time of producing the polylactic acid resin composition, it was determined by whether the working environment was deteriorated by an isocyanate odor. When it did not deteriorate, it was evaluated as good.

(9) Qualitative and quantitative evaluation of isocyanate gas generation:
The sample was heated at 260 ° C. for 8 minutes, and qualitatively and quantitatively analyzed by pyrolysis GC / MS analysis. In addition, fixed_quantity | quantitative_assay was performed using the analytical curve created with isocyanate. GC / MS used was GC / MS Jms Q1000GC K9 manufactured by JEOL Ltd.

Hereinafter, the agent used by this invention is described.
The following agents were produced and used as the cyclic carbodiimide compound.

[Production Example 1] Synthesis of cyclic carbodiimide (CC1):
o- nitrophenol (0.11 mol) and pentaerythrityl tetra bromide (0.025 mol), potassium carbonate _{(0.33mol), N, N- N} 2 dimethylformamide 200ml in reactor installed with a stirrer and a heating device After charging in an atmosphere and reacting at 130 ° C. for 12 hours, DMF was removed under reduced pressure, and the resulting solid was dissolved in 200 ml of dichloromethane and separated three times with 100 ml of water. The organic layer was dehydrated with 5 g of sodium sulfate, and dichloromethane was removed under reduced pressure to obtain an intermediate product D (nitro form).
Next, intermediate product D (0.1 mol), 5% palladium carbon (Pd / C) (2 g), and 400 ml of ethanol / dichloromethane (70/30) were charged into a reactor equipped with a stirrer, and 5 hydrogen substitution was performed. The reaction was performed in a state where hydrogen was constantly supplied at 25 ° C., and the reaction was terminated when there was no decrease in hydrogen. When Pd / C was recovered and the mixed solvent was removed, an intermediate product E (amine body) was obtained.

Next, triphenylphosphine dibromide (0.11 mol) and 150 ml of 1,2-dichloroethane were charged and stirred in a reactor equipped with a stirring device, a heating device, and a dropping funnel in an N ₂ atmosphere. A solution prepared by dissolving the intermediate product E (0.025 mol) and triethylamine (0.25 mol) in 50 ml of 1,2-dichloroethane was gradually added dropwise thereto at 25 ° C. After completion of dropping, the reaction is carried out at 70 ° C. for 5 hours. Thereafter, the reaction solution was filtered, and the filtrate was separated 5 times with 100 ml of water. The organic layer was dehydrated with 5 g of sodium sulfate, and 1,2-dichloroethane was removed under reduced pressure to obtain an intermediate product F (triphenylphosphine compound).
Next, in a reactor equipped with a stirrer and a dropping funnel, di-tert-butyl dicarbonate (0.11 mol), N, N-dimethyl-4-aminopyridine (0.055 mol), dichloromethane under N ₂ atmosphere. 150 ml is charged and stirred. Thereto, 100 ml of dichloromethane in which the intermediate product F (0.025 mol) was dissolved was slowly added dropwise at 25 ° C. After dropping, react for 12 hours. Then, the compound (MW = 516) shown by the following structural formula was obtained by refine | purifying the solid substance obtained by removing dichloromethane. The structure was confirmed by NMR and IR.

[Production Example 2] Production of poly-L-lactic acid (A1):
To 100 parts by weight of L-lactide (manufactured by Musashino Chemical Laboratory, Inc., optical purity 100%), 0.005 parts by weight of tin octylate was added, and the reaction was performed in a reactor equipped with a stirring blade in a nitrogen atmosphere. The mixture was reacted for 2 hours at 0 ° C., and 1.2 times equivalent of phosphoric acid was added as a catalyst deactivator to tin octylate. Thereafter, the remaining lactide was removed at 13.3 Pa, chipped, and poly L-lactic acid ( A1) was obtained.
The obtained poly L-lactic acid had a weight average molecular weight of 152,000, a glass transition temperature (Tg) of 55 ° C., and a melting point of 175 ° C. Table 1 shows the carboxyl group concentration and the stability results against hydrolysis.

[Production Example 3] Synthesis of poly-D-lactic acid (A2):
In the above-mentioned production of PLLA, L-lactide was changed to D-lactide (manufactured by Musashino Chemical Laboratory, Inc., optical purity 100%), and the others were polymerized under the same conditions to obtain poly-D-lactic acid (A2). Obtained.
The obtained poly-D-lactic acid had a weight average molecular weight of 151,000, a glass transition temperature (Tg) of 55 ° C., and a melting point of 175 ° C. Table 1 shows the carboxyl group content and stability results against hydrolysis.

[Example 1] Polylactic acid resin composition containing cyclic carbodiimide:
50 parts by weight of each of poly L-lactic acid (A1) and poly D-lactic acid (A2) and 0.3 parts by weight of a phosphoric acid ester metal salt (“ADEKA STAB” NA-11 manufactured by ADEKA Corporation) were mixed with a blender, 110 ° C. After vacuum drying for 5 hours, from the first supply port of the kneader, after melt melting and kneading while evacuating at a cylinder temperature of 230 ° C. and a vent pressure of 13.3 Pa, 1 part by weight of cyclic carbodiimide (CC1) is supplied from the second supply port. Supply and melt-knead at a cylinder temperature of 230 ° C, extrude strands into a water bath, chip into chips with a chip cutter, and a polylactic acid resin composition (M1) having a stereo complex crystallinity (S) of 100% and a crystal melting temperature of 216 ° C Got. When the polylactic acid resin composition was produced, the working environment was maintained well without feeling an isocyanate odor. Moreover, when it melted at 260 ° C. for 5 minutes, the isocyanate odor evaluation was acceptable. Table 1 shows the carboxyl group concentration of this polylactic acid resin composition and the stability results against hydrolysis. Moreover, about this polylactic acid resin composition, when isocyanate gas generation amount was confirmed by GC / MS, isocyanate gas was not detected.

[Example 2] Polylactic acid resin composition containing cyclic carbodiimide:
50 parts by weight of each of poly L-lactic acid (A1) and poly D-lactic acid (A2) and 0.015 part by weight of a phosphate ester metal salt (“ADEKA STAB” NA-71, manufactured by ADEKA Corporation) were mixed with a blender, 110 ° C. After vacuum drying for 5 hours, from the first supply port of the kneader, after melt melting and kneading while evacuating at a cylinder temperature of 230 ° C. and a vent pressure of 13.3 Pa, 1 part by weight of cyclic carbodiimide (CC1) is supplied from the second supply port. Supplied and melt-kneaded at a cylinder temperature of 265 ° C., extruded into a water tank, extruded into a chip cutter, and converted into a chip by a chip cutter, and a polylactic acid resin composition (M2) having a stereocomplex crystallinity (S) of 100% and a crystal melting temperature of 212 ° C. Got. When the polylactic acid resin composition was produced, the working environment was maintained well without feeling an isocyanate odor. Moreover, when it melted at 260 ° C. for 5 minutes, the isocyanate odor evaluation was acceptable. Table 1 shows the carboxyl group concentration of this polylactic acid resin composition and the stability results against hydrolysis. Moreover, about this polylactic acid resin composition, when isocyanate gas generation amount was confirmed by GC / MS, isocyanate gas was not detected.

[Comparative Example 1] Polylactic acid resin composition not containing stereocomplex polylactic acid:
In Example 1, the crystal melting temperature by DSC was the same as in Example 1 except that 50 parts by weight of poly L-lactic acid (A1) and poly D-lactic acid (A2) were replaced with 100 parts by weight of poly D-lactic acid (A2). A polylactic acid resin composition (M3) at 175 ° C. was obtained.
Generation of isocyanate odor was not felt during the production of the polylactic acid resin composition. Moreover, when it melted at 260 ° C. for 5 minutes, the isocyanate odor evaluation was acceptable. Table 1 shows the carboxyl group concentration of this polylactic acid resin composition and the stability results against hydrolysis.

[Comparative Example 2] Polylactic acid resin composition not containing cyclic carbodiimide:
The same operation as in Example 1 was carried out except that the cyclic carbodiimide (CC1) was not supplied, and a resin (M4) having a stereocomplex crystallinity (S) of 100% and a crystal melting temperature of 217 ° C. was obtained. Table 1 shows the carboxyl group concentration of this polylactic acid resin composition and the stability results against hydrolysis.

[Comparative Example 3] Polylactic acid resin composition not containing cyclic carbodiimide:
In Example 2, the same operation was performed except that the cyclic carbodiimide (CC1) was not supplied, and the kneading temperature was 278 ° C., the stereocomplex crystallinity (S) was 72%, the crystal melting temperature 221 A resin (M5) at 0 ° C. was obtained. Table 1 shows the carboxyl group concentration of this polylactic acid resin composition and the stability results against hydrolysis.

[Comparative Example 4] Polylactic acid resin composition not containing cyclic carbodiimide:
In the same manner as in Example 1, except that the carbodiimide compound was changed to linear carbodiimide Sb-I (“STABAXOL” I manufactured by Rhein Chemie Japan), stereocomplex crystallinity (S) 100%, crystal melting A polylactic acid resin composition (M6) having a temperature of 215 ° C. was obtained. When this polylactic acid resin composition was produced, the generation of isocyanate odor was strong, and it was necessary to install an exhaust device. Moreover, when it melted at 260 ° C. for 5 minutes, the isocyanate odor evaluation was unacceptable. Table 1 shows the carboxyl group concentration of this polylactic acid resin composition and the stability results against hydrolysis.

[Comparative Example 5] Polylactic acid resin composition not containing cyclic carbodiimide:
In Example 1, except that the carbodiimide compound was changed to linear carbodiimide LA-1 (manufactured by Nisshinbo Chemical Co., Ltd., “Carbodilite” LA-1), stereocomplex crystallinity (S) 98%, A polylactic acid resin composition (M7) having a crystal melting temperature of 213 ° C. was obtained. When this polylactic acid resin composition was produced, the generation of isocyanate odor was strong, and it was necessary to install an exhaust device. Moreover, when it melted at 260 ° C. for 5 minutes, the isocyanate odor evaluation was unacceptable. Table 1 shows the carboxyl group concentration of this polylactic acid resin composition and the stability results against hydrolysis. About this polylactic acid resin composition, when isocyanate gas generation amount was confirmed by GC / MS, 430 ppm of isocyanate derived from LA-1 was detected.

[Comparative Example 6] Polylactic acid resin composition without addition of phosphate metal salt:
In Example 1, the same operation was performed except that the phosphate ester metal salt (NA-11) was not supplied, the stereocomplex crystallinity (S) was 77%, the crystal melting temperature was 173 ° C. (homocrystal phase) ) And 220 ° C. (stereocomplex crystal phase) resin (M8) was obtained. Table 1 shows the carboxyl group concentration of this polylactic acid resin composition and the stability results against hydrolysis.

  The polylactic acid resin composition of the present invention is useful as a raw material for various molded articles.

Claims (7)

Stereocomplex polylactic acid (component A), phosphate metal salt represented by the following formula (ii) (component B) and one carbodiimide group, the first nitrogen and the second nitrogen are bonded by a linking group The polylactic acid resin composition containing the compound (C component) represented by the following formula (1) including a cyclic structure.

(In the formula, R ₁ is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. R ₂ and R ₃ are each independently a hydrogen atom or an alkyl group having 1 to 12 carbon atoms. M ₁ is an alkali metal. An atom, an alkaline earth metal atom, a zinc atom or an aluminum atom, p is 1 or 2. q is 0 when M ₁ is an alkali metal atom, an alkaline earth metal atom or a zinc atom, and is an aluminum atom. Is 1 or 2.)

(In the formula, Q is a divalent to tetravalent linking group represented by the following formula (1-1), (1-2) or (1-3)).

(In the formula, Ar ¹ and Ar ² are each independently an aromatic group having 2 to 4 carbon atoms and 5 to 15 carbon atoms. R ¹ and R ² are each independently 1 to 2 carbon atoms having 1 to 4 carbon atoms. 20 aliphatic groups, 2 to 4 valent alicyclic groups having 3 to 20 carbon atoms, or combinations thereof, or these aliphatic groups, alicyclic groups and 2 to 4 valent aromatic carbon atoms having 5 to 15 carbon atoms X ¹ and X ² are each independently a divalent to tetravalent aliphatic group having 1 to 20 carbon atoms, a divalent to tetravalent carbon atom having 3 to 20 alicyclic groups, 2 to 4 A valent aromatic group having 5 to 15 carbon atoms, or a combination thereof, s is an integer of 0 to 10. k is an integer of 0 to 10. When s or k is 2 or more, X ¹ or X ² as a repeating unit may be different from other X ¹ or X ^2. X ³ is a divalent to tetravalent carbon number. An aliphatic group having 1 to 20 carbon atoms, an alicyclic group having 2 to 4 carbon atoms having 3 to 20 carbon atoms, an aromatic group having 2 to 4 carbon atoms having 5 to 15 carbon atoms, or a combination thereof, provided that Ar ¹ , Ar ² , R ¹ , R ² , X ¹ , X ² and X ³ may contain a hetero atom, and when Q is a divalent linking group, Ar ¹ , Ar ² , R 3 ¹ , R ² , X ¹ , X ² and X ³ are all divalent groups, and when Q is a trivalent linking group, Ar ¹ , Ar ² , R ¹ , R ² , X ¹ , X ^{One of 2} and X ³ is a trivalent group, and when Q is a tetravalent linking group, one of Ar ¹ , Ar ² , R ¹ , R ² , X ¹ , X ² and X ³ One of them is a tetravalent group or two are trivalent groups.) Stereocomplex polylactic acid (component A)
(IA) a polylactic acid unit iA in which the L-lactic acid unit is 90 mol% or more and 100 mol% or less, and the D-lactic acid unit and / or the copolymer component unit other than lactic acid is 0 mol% or more and 10 mol% or less, and (IiA) It comprises a polylactic acid unit iiA in which D-lactic acid units are 90 mol% or more and 100 mol% or less, and L-lactic acid units and / or copolymer component units other than lactic acid are 0 mol% or more and 10 mol% or less. ,
The polylactic acid resin composition according to claim 1, wherein (iA) and (iiA) are in the range of 10:90 to 90:10 by weight ratio, and the weight average molecular weight is 50,000 to 500,000. The polylactic acid resin composition according to claim 1, wherein the stereocomplex crystallinity (S) defined by the following formula is 90 to 100%.
S = [ΔHms / (ΔHmh + ΔHms)] × 100
(ΔHms = Stereocomplex phase polylactic acid melting enthalpy, ΔHmh = Polylactic acid homophase crystal melting enthalpy)   The polylactic acid resin composition according to any one of claims 1 to 3, wherein the compound (C component) containing a cyclic structure has 8 to 50 atoms forming a ring. The polylactic acid resin composition according to any one of claims 1 to 3, wherein the compound (C component) containing a cyclic structure is represented by the following formula (2).

(In the formula, Q _a is a divalent linking group represented by the following formula (2-1), (2-2) or (2-3).)

(In the formula, Ar _a ¹ , Ar _a ² , R _a ¹ , R _a ² , X _a ¹ , X _a ² , X _a ³ , s and k are represented by the formulas (1-1) to (1-3), respectively. The same as Ar ¹ , Ar ² , R ¹ , R ² , X ¹ , X ² , X ³ , s and k in the inside.) The polylactic acid resin composition according to any one of claims 1 to 3, wherein the compound (C component) containing a cyclic structure is represented by the following formula (3).

(Wherein Q _b is a trivalent linking group represented by the following formula (3-1), (3-2) or (3-3). Y is an atom, an atomic group or a polymer. .)

(In the formula, Ar _b ¹ , Ar _b ² , R _b ¹ , R _b ² , X _b ¹ , X _b ² , X _b ³ , s and k are represented by the formulas (1-1) to (1-3), respectively. of ^{Ar 1, Ar 2, R 1} , R 2, X 1, X 2, X 3, the same as the s and k. However, one of these is Ru trivalent group der.) The polylactic acid resin composition according to any one of claims 1 to 3, wherein the compound (C component) containing a cyclic structure is represented by the following formula (4).

(Wherein Q _c is a tetravalent linking group represented by the following formula (4-1), (4-2) or (4-3). Z ¹ and Z ² are each independently an atom; , Atomic group or polymer. )

(In the formula, Ar _c ¹ , Ar _c ² , R _c ¹ , R _c ² , X _c ¹ , X _c ² , X _c ³ , s and k are respectively represented by formulas (1-1) to (1-3) Are the same as A _r ¹ , A _r ² , R ¹ , R ² , X ¹ , X ² , X ³ , s and k, provided that one of these is a tetravalent group or One is a trivalent group .)