JP2011127037A - Molded article with low photoelasticity - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a molded article with a low photoelastic modulus that is excellent in transparency, thermal resistance and impact resistance. <P>SOLUTION: The molded article includes a resin composition containing as the main component a mixture (X) of an aliphatic polycarbonate resin (A) having a structural unit (a) derived from a dihydroxy compound with a moiety represented by general formula (1) and a structural unit (b) derived from cyclohexane dimethanol and an aromatic polycarbonate resin (B), and has a photoelastic modulus of 7×10<SP>-11</SP>Pa<SP>-1</SP>or lower at a light wavelength of 600 nm. The mixture (X) has a single glass transition temperature, which is as high as or higher than the glass transition temperature of the aliphatic polycarbonate resin (A) and as low as or lower than the glass transition temperature of the aromatic polycarbonate resin (B), (provided that the case where the moiety represented by general formula (1) constitutes a part of -CH<SB>2</SB>-O-H is excluded). <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a molded article that hardly causes a phase difference due to stress, that is, has a low photoelastic coefficient, and is excellent in transparency, heat resistance, and impact resistance.

  Polyvinyl chloride resin, which has been known as a resin that has a good balance of physical properties such as transparency and mechanical properties, can be widely controlled by plasticizers and various compounding agents depending on the application. Has been used for various purposes. However, in recent years, from the viewpoint of environmental problems and the like, the conversion from polyvinyl chloride resin to other resins has been actively studied. One of the promising candidates for a substitute resin for polyvinyl chloride resin is a polycarbonate resin excellent in transparency, heat resistance, and impact resistance, and is used in various applications. However, since the polycarbonate resin has a high melt viscosity and low fluidity, the polycarbonate resin has a disadvantage that it is inferior in moldability when molding a sheet, a film, a molded product or the like. In particular, when used in optical applications, polycarbonate resins have a high photoelastic coefficient and are liable to cause a phase difference due to stress.

  In order to solve the moldability of such a polycarbonate resin, many resin compositions of a polycarbonate resin and a polyester resin have been conventionally proposed. For example, Patent Document 1 discloses a resin composition in which a polycarbonate resin and a polyester resin such as polybutylene terephthalate and polyethylene terephthalate are mixed, and Patent Document 2 discloses a transesterification rate of the polycarbonate resin and the polyester resin. By controlling the above, a resin composition having improved flowability and excellent transparency, solvent resistance and impact resistance is disclosed. Patent Documents 3 and 4 disclose resin compositions made of a polycarbonate resin and an amorphous polyester resin.

JP 58-18391 A Japanese Patent Laid-Open No. 10-87973 JP 59-120648 A JP-A-10-101918

  However, the secondary processed product obtained from the conventional resin composition as disclosed in Patent Document 1 still does not satisfy sufficient transparency. This is presumably because the transesterification reaction between the polycarbonate resin and the polyester resin does not proceed sufficiently. Moreover, the resin composition disclosed in Patent Document 2 has problems such as difficulty in controlling the transesterification reaction and the need to use a polycarbonate resin having a functional group at the terminal.

  Although the resin compositions disclosed in Patent Document 3 and Patent Document 4 are excellent in transparency, heat resistance, and impact resistance, the photoelastic coefficient is increased by mixing an amorphous polyester resin. There was a problem that it would be even higher.

  As described above, in the above-described technique, it has been very difficult to provide a molded article having a low photoelastic coefficient and excellent transparency, heat resistance, and impact resistance.

  Accordingly, an object of the present invention is to provide a molded article having a low photoelastic coefficient and excellent in transparency, heat resistance, and impact resistance in view of such problems of the prior art.

1st this invention contains the structural unit (a) derived from the dihydroxy compound which has the site | part represented by following General formula (1) in a part of structure, and the structural unit (b) derived from cyclohexane dimethanol. The resin composition mainly comprises a mixture (X) composed of an aliphatic polycarbonate resin (A) and an aromatic polycarbonate resin (B), the mixture (X) has a single glass transition temperature, and The glass transition temperature is not less than the glass transition temperature of the aliphatic polycarbonate resin (A) and not more than the glass transition temperature of the aromatic polycarbonate resin (B), and the photoelastic coefficient at a light wavelength of 600 nm is 7 ×. The present invention provides a molded product characterized by being 10 ⁻¹¹ Pa ⁻¹ or less.
The second aspect of the present invention includes a structural unit (a) derived from a dihydroxy compound having a site represented by the following general formula (1) in a part of the structure and a structural unit (b) derived from cyclohexanedimethanol. A resin composition comprising as a main component a mixture (X) comprising an aliphatic polycarbonate resin (A) and an aromatic polycarbonate resin (B), wherein the aliphatic polycarbonate resin (A) The proportion is 45 mol% or more and 80 mol% or less, the proportion of the aliphatic polycarbonate resin (A) in the mixture (X) is 1 mass% or more and 99 mass% or less, and the light wavelength is 600 nm. The molded article is characterized by having a photoelastic coefficient of 7 × 10 ⁻¹¹ Pa ⁻¹ or less.

(However, the site represented by the above general formula (1) unless it is part of _-CH 2 -O-H.)

  ADVANTAGE OF THE INVENTION According to this invention, the molded object which has the low photoelastic coefficient, the outstanding transparency, heat resistance, and impact resistance can be provided.

  Hereinafter, a molded body as one example of an embodiment of the present invention will be described. However, the scope of the present invention is not limited to the embodiments described below.

  In the present specification, “main component” is intended to allow other components to be included within a range that does not hinder the action / effect of the resin constituting the molded article of the present invention. Further, this term does not limit the specific content, but it is 50% by mass or more, preferably 60% by mass or more, more preferably 70% by mass or more, based on the total constituent components of the resin composition. It is a component occupying a range of mass% or less.

<Aliphatic polycarbonate resin (A)>
As the aliphatic polycarbonate resin (A) used in the present invention, a structural unit derived from a dihydroxy compound having a site represented by the following general formula (1) in a part of the structure, and a structural unit derived from cyclohexanedimethanol A polycarbonate resin containing is used.

(However, the site represented by the above general formula (1) unless it is part of _-CH 2 -O-H.)
That is, the said dihydroxy compound says what contains at least the site | part of the said General formula (1) further two hydroxyl groups.

The dihydroxy compound having a site represented by the general formula (1) in a part of the structure is not particularly limited as long as a part of the molecular structure is represented by the general formula (1). Specifically, 9,9-bis (4- (2-hydroxyethoxy) phenyl) fluorene, 9,9-bis (4- (2-hydroxyethoxy) -3-methylphenyl) fluorene, 9,9 -Bis (4- (2-hydroxyethoxy) -3-isopropylphenyl) fluorene, 9,9-bis (4- (2-hydroxyethoxy) -3-isobutylphenyl) fluorene, 9,9-bis (4- ( 2-hydroxyethoxy) -3-tert-butylphenyl) fluorene, 9,9-bis (4- (2-hydroxyethoxy) -3-cyclohexylphenyl) fluorene, 9,9- (4- (2-hydroxyethoxy) -3-phenylphenyl) fluorene, 9,9-bis (4- (2-hydroxyethoxy) -3,5-dimethylphenyl) fluorene, 9,9-bis (4- (2-hydroxyethoxy) -3-tert-butyl-6-methylphenyl) fluorene 9,9-bis (4- (3-hydroxy-2,2-dimethylpropoxy) phenyl) fluorene, etc., an aromatic group in the side chain A compound having an ether group bonded to an aromatic group in the main chain, an anhydrosugar alcohol typified by a dihydroxy compound represented by the following general formula (2), and a spiro represented by the following general formula (3) Examples of the dihydroxy compound represented by the following general formula (2) include isosorbide having a stereoisomeric relationship, such as a compound having a cyclic ether structure such as glycol. -Isomannid, include the Isoidetto. Moreover, as a dihydroxy compound represented by the following general formula (3), 3,9-bis (1,1-dimethyl-2-hydroxyethyl) -2,4,8,10-tetraoxaspiro (5.5) ) Undecane (common name: spiroglycol), 3,9-bis (1,1-diethyl-2-hydroxyethyl) -2,4,8,10-tetraoxaspiro (5.5) undecane, 3,9- And bis (1,1-dipropyl-2-hydroxyethyl) -2,4,8,10-tetraoxaspiro (5.5) undecane.
These may be used alone or in combination of two or more.

(Wherein R _{1 to} R ₄ are each independently an alkyl group having 1 to 3 carbon atoms.)

  Among these, it is most preferable to use isosorbide which is industrially easily available and is derived from plant materials, and these may be used alone or in combination of two or more.

It is important to include a structural unit (b) derived from cyclohexanedimethanol as a structural unit other than the structural unit (a), and in particular, derived from cyclohexanedimethanol in the aliphatic polycarbonate resin (A). The proportion of the structural unit (b) is preferably 45 mol% or more and 80 mol% or less. The lower limit of the structural unit (b) derived from cyclohexanedimethanol is more preferably 50 mol%, and even more preferably 55 mol%. By making it 45 mol% or more, the compatibility with the aromatic polycarbonate resin (B) is improved, the transparency and mechanical properties of the mixture (X) and the molded product are sufficiently improved, and the photoelastic coefficient is lowered. it can. On the other hand, as an upper limit, More preferably, it is 75 mol%, More preferably, it is 70 mol%. By setting it to 80 mol% or less, it is possible to prevent a significant decrease in heat resistance and softening due to the aliphatic polycarbonate resin (A), and it can be used in a wide range of applications.
Of the cyclohexanedimethanol, 1,4-cyclohexanedimethanol, which is industrially easily available, is preferable.

  Furthermore, the aliphatic polycarbonate resin (A) can also contain a structural unit other than the structural unit (a) and the structural unit (b). For example, the aliphatic polycarbonate resin described in WO 2004/111106 pamphlet. An aliphatic dihydroxy compound, an alicyclic dihydroxy compound described in International Publication No. 2007/148604 pamphlet, and the like can be given.

  Among structural units derived from the above aliphatic dihydroxy compounds, selected from the group consisting of ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, and 1,6-hexanediol. It is preferable to include a structural unit derived from at least one compound.

  Among the structural units derived from the alicyclic dihydroxy compound, those containing a 5-membered ring structure or a 6-membered ring structure are preferable. The six-membered ring structure may be fixed in a chair shape or a boat shape by a covalent bond. By including a structural unit derived from an alicyclic dihydroxy compound having a 5-membered ring structure or a 6-membered ring structure, the heat resistance of the obtained polycarbonate can be increased. The number of carbon atoms contained in the alicyclic dihydroxy compound is usually 70 or less, preferably 50 or less, more preferably 30 or less.

  Examples of the alicyclic dihydroxy compound containing the 5-membered ring structure or the 6-membered ring structure include those described in the above-mentioned International Publication No. 2007/148604, and tricyclodecane dimethanol, adamantanediol, and penta Cyclopentadecanedimethanol can be preferably exemplified, and these may be used alone or in combination of two or more.

The glass transition temperature of the aliphatic polycarbonate resin (A) is preferably 75 ° C. or higher and 105 ° C. or lower, more preferably 80 ° C. or higher and 105 ° C. or lower, and 85 ° C. or higher and 105 ° C. or lower. Is more preferable. By using the aliphatic polycarbonate resin (A) having a glass transition temperature in such a range, a molded product having excellent heat resistance can be provided.
The reduced viscosity, which is an index of the molecular weight of the aliphatic polycarbonate resin (A), was prepared by using methylene chloride as a solvent and adjusting the polycarbonate concentration to 0.60 g / dl precisely at a temperature of 20.0 ° C. ± 0.1 ° C. Usually, it is 0.20 dl / g or more and 1.0 dl / g or less, preferably 0.3 dl / g or more and 0.8 dl / g or less.
If the reduced viscosity of the aliphatic polycarbonate resin (A) is too low, the mechanical strength when molded into a lens or the like tends to decrease. On the other hand, if the reduced viscosity of the aliphatic polycarbonate resin (A) is excessively high, fluidity during molding is lowered, cycle characteristics are lowered, and distortion of the molded product tends to increase.

The aliphatic polycarbonate resin (A) can be produced by a generally used polymerization method, and may be either a phosgene method or a transesterification method in which it reacts with a carbonic acid diester. In particular, in the presence of a polymerization catalyst, a dihydroxy compound having a site represented by the general formula (1) in a part of the structure, cyclohexanedimethanol, other dihydroxy compounds used as necessary, and a carbonic acid diester The transesterification method in which is reacted is preferred.
In the transesterification method, a dihydroxy compound having a site represented by the general formula (1) in a part of the structure, cyclohexanedimethanol, another dihydroxy compound used as necessary, and a carbonic acid diester are used as a base. It is a manufacturing method which adds an acidic substance which neutralizes this basic catalyst, and also this basic catalyst, and performs transesterification.

  Representative examples of carbonic acid diesters include diphenyl carbonate, ditolyl carbonate, bis (chlorophenyl) carbonate, m-cresyl carbonate, dinaphthyl carbonate, bis (biphenyl) carbonate, diethyl carbonate, dimethyl carbonate, dibutyl carbonate, and dicyclohexyl carbonate. Can be mentioned. Of these, diphenyl carbonate is particularly preferably used.

<Aromatic polycarbonate resin (B)>
The aromatic polycarbonate resin (B) used in the present invention may be either a homopolymer or a copolymer. The aromatic polycarbonate resin (B) may have a branched structure or a linear structure, or may be a mixture of a branched structure and a linear structure.

  As a method for producing the aromatic polycarbonate resin (B) used in the present invention, any known method such as a phosgene method, a transesterification method, or a pyridine method may be used. As an example, a method for producing an aromatic polycarbonate resin by a transesterification method will be described below.

The transesterification method is a production method in which a divalent phenol and a carbonic acid diester are added with a basic catalyst, and further an acidic substance that neutralizes the basic catalyst is added to perform melt transesterification polycondensation. Representative examples of the dihydric phenol include bisphenols, and 2,2-bis (4-hydroxyphenyl) propane, that is, bisphenol A is particularly preferably used. Further, a part or all of bisphenol A may be replaced with another dihydric phenol. Other dihydric phenols include hydroquinone, 4,4-dihydroxydiphenyl, bis (4-hydroxyphenyl) alkanes such as bis (4-hydroxyphenyl) methane and 1,1-bis (4-hydroxyphenyl) ethane, , 1-bis (4-hydroxyphenyl) cyclohexane, bis (4-hydroxyphenyl) cycloalkane, bis (4-hydroxyphenyl) sulfide, bis (4-hydroxyphenyl) sulfone, bis (4-
Compounds such as hydroxyphenyl) sulfoxide, bis (4-hydroxyphenyl) ether, 2,2-bis (3-methyl-4-hydroxyphenyl) propane, 2,2-bis (3,5-dimethyl-4-hydroxy) Alkylated bisphenols such as phenyl) propane, 2,2-bis (3,5-dibromo-4-hydroxyphenyl) propane, 2,2-bis (3,5-dichloro-4-hydroxyphenyl) propane, etc. And halogenated bisphenols.

Representative examples of carbonic acid diesters include diphenyl carbonate, ditolyl carbonate, bis (chlorophenyl) carbonate, m-cresyl carbonate, dinaphthyl carbonate, bis (biphenyl) carbonate, diethyl carbonate, dimethyl carbonate, dibutyl carbonate, dicyclohexyl carbonate, and the like. Is mentioned. Of these, diphenyl carbonate is particularly preferably used.

The viscosity average molecular weight of the aromatic polycarbonate resin (B) used in the present invention is usually 8,000 or more and 30,000 or less, preferably 10,000 or more and 25,000, from the balance of mechanical properties and molding processability. The range is as follows. The reduced viscosity of the aromatic polycarbonate resin (B) was measured at a temperature of 20.0 ° C. ± 0.1 ° C. using methylene chloride as a solvent and the polycarbonate concentration was precisely adjusted to 0.60 g / dl. Usually, it is 0.23 dl / g or more and 0.72 dl / g or less, preferably 0.27 dl / g or more and 0.61 dl / g or less.
In the present invention, the aromatic polycarbonate resin (B) may be used alone or in combination of two or more.

  In the present invention, the aromatic polycarbonate resin (B) means that at least 50 mol% (preferably 70 mol% or more, more preferably 90 mol% or more) of one or more aromatic rings in the structural unit derived from dihydric phenol. The aromatic ring may have a substituent. Moreover, what corresponds to both an aliphatic polycarbonate resin (A) and an aromatic polycarbonate (B) shall be included in an aliphatic polycarbonate resin (A).

<Mixture (X)>
The mixture (X) in the present invention is a mixture having a characteristic that the glass transition temperature is single.

  In the present invention, the single glass transition temperature of the mixture (X) means that the mixture (X) has a dynamic viscoelasticity at a strain of 0.1%, a frequency of 10 Hz, and a heating rate of 3 ° C./min. There is one main dispersion peak of loss tangent (tan δ) measured by temperature dispersion measurement (dynamic viscoelasticity measurement of JIS K7198A method), in other words, there is one maximum value of loss tangent (tan δ). Meaning. When the glass transition temperature of the mixture (X) is single, the obtained molded product can realize excellent transparency.

The single glass transition temperature of the mixture (X) means that there is one main dispersion peak of the loss modulus (E ″) measured in the dynamic viscoelasticity measurement for the mixture (X). In other words, it can be said that there is one maximum value of the loss elastic modulus (E ″).
In addition to the dynamic viscoelasticity measurement, a single glass transition temperature can be confirmed by differential scanning calorimetry. Specifically, when the glass transition temperature is measured using a differential scanning calorimeter (DSC) at a heating rate of 10 ° C./min according to JIS K7121, only one inflection point indicating the glass transition temperature appears. It can also be said to be a thing.

  In general, a single glass transition temperature of a polymer blend composition means that the resin to be mixed is in a compatible state on the nanometer order (molecular level). Can be acknowledged.

  The glass transition temperature of the mixture (X) is represented by a temperature indicating the peak value of the main dispersion of loss tangent (tan δ) measured by the above-described dynamic viscoelasticity temperature dispersion measurement, and the glass transition temperature The temperature ranges from the glass transition temperature of the aliphatic polycarbonate resin (A) to the glass transition temperature of the aromatic polycarbonate resin (B).

The proportion of the aliphatic polycarbonate resin (A) in the mixture (X) comprising the aliphatic polycarbonate resin (A) and the aromatic polycarbonate resin (B) is in the range of 1% by mass to 99% by mass. Although it can mix arbitrarily, especially regarding a lower limit, it is preferable that it is 50 mass% or more, it is more preferable that it is 55 mass% or more, and it is especially preferable that it is 60 mass% or more. By making the ratio of the aliphatic polycarbonate resin (A) 50% by mass or more and 99% by mass or less, it is excellent not only in heat resistance and impact resistance but also in weather resistance. In contrast, an excellent molded body can be provided.

  In addition, the aliphatic polycarbonate resin (A) and the aromatic polycarbonate resin (B) constituting the molded body of the present invention can be selected by selecting the type and ratio of the structural unit, so that the aliphatic polycarbonate resin (A) and the fragrance are selected. It is possible to improve the compatibility with the aromatic polycarbonate resin (B), and the temperature dispersion of dynamic viscoelasticity in the mixture (X) comprising the aliphatic polycarbonate resin (A) and the aromatic polycarbonate resin (B). The glass transition temperature which is the peak value of the main dispersion of loss tangent (tan δ) measured by measurement is single, and the glass transition temperature is equal to or higher than the glass transition temperature of the aliphatic polycarbonate resin (A). It is below the glass transition temperature of the polycarbonate resin (B) and not only has excellent heat resistance and impact resistance, but also has transparency. Is may be a photoelastic coefficient lower moldings.

  Furthermore, the glass transition temperature of the mixture (X) in the present invention is preferably 75 ° C. or higher and 130 ° C. or lower, more preferably 80 ° C. or higher and 125 ° C. or lower, and 85 ° C. or higher and 120 ° C. or lower. More preferably. By setting the glass transition temperature of the mixture (X) within such a range, a molded article having excellent heat resistance can be provided.

Furthermore, in the molded article of the present invention, it is important that the photoelastic coefficient at a light wavelength of 600 nm is 7 × 10 ⁻¹¹ Pa ⁻¹ or less, and 6.5 × 10 ⁻¹¹ Pa ⁻¹ or less. More preferably, it is 6 × 10 ⁻¹¹ Pa ⁻¹ or less. If the photoelastic coefficient is within such a range, a phase difference due to stress hardly occurs, and it can be widely used for optical applications such as various lenses.

<Resin other than polycarbonate resin>
The molded object of this invention consists of a resin composition which has a mixture (X) as a main component. If mixture (X) is a main component, resin other than polycarbonate resin and additives other than resin can also be blended.
Specific examples of resins other than polycarbonate resins that are compounded for the purpose of further improving and adjusting molding processability and various physical properties include resins such as polyester resins, polyethers, polyamides, polyolefins, polymethyl methacrylates, and core-shell types. And rubber-like modifiers such as graft-type or linear random and block copolymers. The compounding amount of the resin other than the polycarbonate resin is preferably 1% by mass or more and 30% by mass or less with respect to 100% by mass of the resin composition constituting the molded body of the present invention. It is more preferable to mix | blend in the ratio of% to 20 mass%, and it is still more preferable to mix | blend in the ratio of 5 mass% or more and 10 mass% or less.

<Heat stabilizer>
The molded article of the present invention can be blended with a heat stabilizer in order to prevent a decrease in molecular weight and a deterioration in hue during molding. Examples of the heat stabilizer include phosphorous acid, phosphoric acid, phosphonous acid, phosphonic acid, and esters thereof. Specifically, triphenyl phosphite, tris (nonylphenyl) phosphite, tris (2 , 4-Di-tert-butylphenyl) phosphite, tridecyl phosphite, trioctyl phosphite, trioctadecyl phosphite, didecyl monophenyl phosphite, dioctyl monophenyl phosphite, diisopropyl monophenyl phosphite, monobutyl diphenyl Phosphite, monodecyl diphenyl phosphite, monooctyl diphenyl phosphite, bis (2,6-di-tert-butyl-4-methylphenyl) pentaerythritol diphosphite, 2,2-methylenebis (4,6-di-) tert -Butylphenyl) octyl phosphite, bis (nonylphenyl) pentaerythritol diphosphite, bis (2,4-di-tert-butylphenyl) pentaerythritol diphosphite, distearyl pentaerythritol diphosphite, tributyl phosphate, triethyl Phosphate, trimethyl phosphate, triphenyl phosphate, diphenyl monoorthoxenyl phosphate, dibutyl phosphate, dioctyl phosphate, diisopropyl phosphate, 4,4′-biphenylenediphosphinic acid tetrakis (2,4-di-tert-butylphenyl), benzenephosphonic acid Examples thereof include dimethyl, diethyl benzenephosphonate, and dipropyl benzenephosphonate. Among them, trisnonylphenyl phosphite, trimethyl phosphate, tris (2,4-di-tert-butylphenyl) phosphite, bis (2,4-di-tert-butylphenyl) pentaerythritol diphosphite, bis (2 , 6-Di-tert-butyl-4-methylphenyl) pentaerythritol diphosphite and dimethyl benzenephosphonate are preferably used. These heat stabilizers may be used alone or in combination of two or more. The amount of the heat stabilizer is preferably 0.0001% by mass or more and 1% by mass or less with respect to 100% by mass of the resin composition constituting the molded article of the present invention. It is more preferable to mix | blend in the ratio of the mass% or more and 0.5 mass% or less, and it is further more preferable to mix | blend in the ratio of 0.001 mass% or more and 0.2 mass% or less. By blending the heat stabilizer within such a range, it is possible to prevent a decrease in molecular weight or discoloration of the resin without causing bleeding of the additive.

<Antioxidant>
Moreover, the antioxidant conventionally known for the purpose of antioxidant can be mix | blended with the molded object of this invention. Examples of the antioxidant include pentaerythritol tetrakis (3-mercaptopropionate), pentaerythritol tetrakis (3-lauryl thiopropionate), glycerol-3-stearyl thiopropionate, triethylene glycol bis [3 -(3-tert-butyl-5-methyl-4-hydroxyphenyl) propionate], 1,6-hexanediol-bis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], Pentaerythritol-tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate, 1, 3,5-trimethyl-2,4 6-tris (3,5-di-tert-butyl-4-hydroxybenzyl) benzene, N, N-hexamethylenebis (3,5-di-tert-butyl-4-hydroxy-hydrocinnamide), 3, 5-di-tert-butyl-4-hydroxy-benzylphosphonate-diethyl ester, tris (3,5-di-tert-butyl-4-hydroxybenzyl) isocyanurate, 4,4′-biphenylenediphosphinic acid tetrakis (2, 4-di-tert-butylphenyl), 3,9-bis {1,1-dimethyl-2- [β- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionyloxy] ethyl} -2 , 4,8,10-tetraoxaspiro (5,5) undecane and the like. The blending amount of the antioxidant is preferably 0.0001% by mass or more and 1% by mass or less with respect to 100% by mass of the resin composition constituting the molded article of the present invention. It is more preferable to mix | blend in the ratio of the mass% or more and 0.5 mass% or less, and it is further more preferable to mix | blend in the ratio of 0.001 mass% or more and 0.2 mass% or less. By blending the antioxidant in such a range, the oxidation deterioration of the resin can be prevented without causing the bleeding of the antioxidant on the surface of the molded body and the deterioration of the mechanical properties of various molded products.

<Lubricant>
In addition, a lubricant can be blended for the purpose of imparting surface lubricity to the molded article of the present invention. Examples of the lubricant include higher fatty acid esters of monohydric or polyhydric alcohol, higher fatty acid, paraffin wax, beeswax, olefin wax, olefin wax containing carboxy group and / or carboxylic anhydride group, silicone oil, organopoly Examples thereof include siloxane.

The higher fatty acid ester is preferably a partial ester or a total ester of a monovalent or polyhydric alcohol having 1 to 20 carbon atoms and a saturated fatty acid having 10 to 30 carbon atoms. Such partial esters or total esters of monohydric or polyhydric alcohols and saturated fatty acids include stearic acid monoglyceride, stearic acid diglyceride, stearic acid triglyceride, stearic acid monosorbate, stearyl stearate, behenic acid monoglyceride, behenyl behenate, Pentaerythritol monostearate, pentaerythritol tetrastearate, pentaerythritol tetrapelargonate, propylene glycol monostearate, stearyl stearate, palmityl palmitate, butyl stearate, methyl laurate, isopropyl palmitate, biphenyl biphenate Sorbitan monostearate, 2-ethylhexyl stearate and the like. Of these, stearic acid monoglyceride, stearic acid triglyceride, pentaerythritol tetrastearate and behenyl behenate are preferably used. As the higher fatty acid, a saturated fatty acid having 10 to 30 carbon atoms is preferable. Such fatty acids include myristic acid, lauric acid, palmitic acid, stearic acid, behenic acid and the like. These lubricants may be used alone or in combination of two or more. The blending amount of the lubricant is preferably 0.0001% by mass or more and 1% by mass or less with respect to 100% by mass of the resin composition constituting the molded body of the present invention, and is 0.0005% by mass. As mentioned above, it is more preferable to mix | blend in the ratio of 0.5 mass% or less, and it is further more preferable to mix | blend in the ratio of 0.001 mass% or more and 0.2 mass% or less. By blending the lubricant in such a range, it is possible to impart surface lubricity without causing the bleeding of the lubricant on the surface of the molded body and the deterioration of the mechanical properties of various molded products.

<Ultraviolet absorber, light stabilizer>
For the purpose of further improving the weather resistance of the molded article of the present invention, an ultraviolet absorber and a light stabilizer can be blended. Examples of such ultraviolet absorbers and light stabilizers include 2- (2′-hydroxy-5′-tert-octylphenyl) benzotriazole, 2- (3-ter
t-butyl-5-methyl-2-hydroxyphenyl) -5-chlorobenzotriazole, 2- (5-methyl-2-hydroxyphenyl) benzotriazole, 2- [2-hydroxy-3,5-bis (α, α-dimethylbenzyl) phenyl] -2H-benzotriazole, 2,2′-methylenebis (4-cumyl-6-benzotriazolephenyl), 2,2′-p-phenylenebis (1,3-benzoxazine-4- ON). The melting point of the ultraviolet absorber is particularly preferably in the range of 120 to 250 ° C. When an ultraviolet absorber having a melting point of 120 ° C. or higher is used, fogging due to gas on the surface of the molded article is reduced and improved. Specifically, 2- (2′-hydroxy-5′-methylphenyl) benzotriazole,
2- (2'-hydroxy-3'-tert-butyl-5'-methylphenyl) -5-chlorobenzotriazole, 2- [2'-hydroxy-3 '-(3 ", 4", 5 ", 6 "-Tetrahydrophthalimidomethyl) -5'-methylphenyl] benzotriazole, 2,2-methylenebis [4- (1,1,3,3-tetramethylbutyl) -6- (2H-benzotriazol-2-yl) Benzotriazole-based UV absorbers such as phenol and 2- (2-hydroxy-3,5-dicumylphenyl) benzotriazole are used, and among these, 2- (2-hydroxy-3,5-dicine is particularly preferable. Milphenyl) benzotriazole, 2,2-methylenebis [4- (1,1,3,3-tetramethylbutyl) -6- (2H-benzotriazole-
2-yl) phenol is preferred. These ultraviolet absorbers and light stabilizers may be used alone or in combination of two or more. The ultraviolet absorber and the light stabilizer are preferably blended in a proportion of 0.0001% by mass or more and 1% by mass or less with respect to 100% by mass of the resin composition constituting the molded article of the present invention. , 0.0005 mass% or more and 0.5 mass% or less is more preferable, and 0.001 mass% or more and 0.2 mass% or less is more preferable. By blending UV absorbers and light stabilizers within this range, the weather resistance of the molded body is improved without causing UV absorbers, light stabilizer bleed to the surface of the molded body, and deterioration of mechanical properties of various molded products. can do.

<Epoxy compound>
Furthermore, in order to further improve the hydrolysis resistance of the molded article of the present invention, an epoxy compound can be blended. Specific examples of the epoxy compound include epoxidized soybean oil, epoxidized linseed oil, phenyl glycidyl ether, allyl glycidyl ether, t-butylphenyl glycidyl ether, 3,4-epoxycyclohexylmethyl-3 ′, 4′-epoxycyclohexyl. Carboxylate, 3,4-epoxy-6-methylcyclohexylmethyl-3 ′, 4′-epoxy-6′-methylcyclohexylcarboxylate, 2,3-epoxycyclohexylmethyl-3 ′, 4′-epoxycyclohexylcarboxylate, 4- (3,4-epoxy-5-methylcyclohexyl) butyl-3 ′, 4′-epoxycyclohexylcarboxylate, 3,4-epoxycyclohexylethylene oxide, cyclohexylmethyl-3,4-epoxycyclohexylcarboxylate 3,4-epoxy-6-methylcyclohexylmethyl-6′-methylsiloxycarboxylate, bisphenol A diglycidyl ether, tetrabromobisphenol A glycidyl ether, diglycidyl ester of phthalic acid, diglycidyl ester of hexahydrophthalic acid Bis-epoxy dicyclopentadienyl ether, bis-epoxy ethylene glycol, bis-epoxy cyclohexyl adipate, butadiene diepoxide, tetraphenylethylene epoxide, octyl epoxy tarate, epoxidized polybutadiene, 3,4-dimethyl-1,2, -Epoxycyclohexane, 3,5-dimethyl-1,2-epoxycyclohexane, 3-methyl-5-t-butyl-1,2-epoxycyclohexane, octadecyl-2,2- Dimethyl-3,4-epoxycyclohexyl carboxylate, N-butyl-2,2-dimethyl-3,4-epoxycyclohexyl carboxylate, cyclohexyl-2-methyl-3,4-epoxycyclohexyl carboxylate, N-butyl-2 -Isopropyl-3,4-epoxy-5-methylcyclohexyl carboxylate, octadecyl-3,4-epoxycyclohexyl carboxylate, 2-ethylhexyl-3 ', 4'-epoxycyclohexyl carboxylate, 4,6-dimethyl-2, 3-epoxycyclohexyl-3 ′, 4′-epoxycyclohexylcarboxylate, 4,5-epoxytetrahydrophthalic anhydride, 3-tert-butyl-4,5-epoxytetrahydrophthalic anhydride, diethyl-4,5-epoxy Cis-1 2-cyclohexyl dicarboxylate, di -N- butyl -3-t-butyl-4,5-epoxy - such as cis-1,2-cyclohexyl dicarboxylate, and the like. Bisphenol A diglycidyl ether is preferable from the viewpoint of compatibility. The compounding amount of the epoxy compound is preferably 0.0001% by mass or more and 5% by mass or less with respect to 100% by mass of the resin composition constituting the molded article of the present invention. It is more preferable to mix | blend in the ratio of 001 mass% or more and 1 mass% or less, and it is more preferable to mix | blend in the ratio of 0.005 mass% or more and 0.5 mass% or less. By blending the epoxy compound in such a range, the hydrolysis resistance of the molded product can be improved without causing bleeding of the epoxy compound on the surface of the molded product and a decrease in mechanical properties of various molded products.

  In addition to the above, additives such as plasticizers, pigments, dyes, and fillers can be further blended in the molded article of the present invention.

<Transparency of molded body>
The total light transmittance measured based on JIS K7361-1 at a thickness of 1 mm of the molded body is preferably 80% or more, more preferably 83% or more, and further preferably 85% or more. And haze measured based on JIS K7105 is preferably 5% or less, more preferably 4% or less, and further preferably 3% or less. When the total light transmittance and the haze are within such ranges, it can be widely used in various applications that require transparency.

<Use of this molded product>
As an example of this molded object, a film, a plate, or an injection molded product can be mentioned. As a specific molding method, aliphatic polycarbonate resin (A), aromatic polycarbonate resin (B) and, if necessary, other raw materials such as resins and additives are directly mixed, and the resulting mixture is used in an extruder or an injection molding machine. The raw material is melted and mixed using a twin screw extruder, extruded into a strand shape to produce a pellet, and then the pellet is put into an extruder or an injection molding machine to be molded. A method can be mentioned. In any method, it is necessary to consider a decrease in molecular weight due to hydrolysis of the polycarbonate resin, and the latter is preferably selected for uniform mixing. Therefore, the latter manufacturing method will be described below.

  Aliphatic polycarbonate resin (A), aromatic polycarbonate resin (B), and other resins and additives as necessary, after sufficiently drying to remove moisture, then melt mixed using a twin screw extruder, Extruded into a strand shape to produce pellets. At this time, it is preferable to appropriately select the melt extrusion temperature in consideration of the viscosity changing depending on the composition ratio and blending ratio of each raw material. Specifically, the molding temperature is preferably 200 ° C. or higher and 260 ° C. or lower, more preferably 210 ° C. or higher and 250 ° C. or lower, and further preferably 220 ° C. or higher and 240 ° C. or lower.

  After the pellets produced by the above method are sufficiently dried to remove moisture, a film, a plate, or an injection molded product can be molded by the following method.

  As a method for forming a film or plate, in addition to roll stretching, a tenter stretching method, a tubular method, and an inflation method, a general T die casting method, a pressing method, or the like can be employed as a method for forming a film or plate.

  In general, "film" is a thin flat product whose thickness is extremely small compared to the length and width and whose maximum thickness is arbitrarily limited, and is usually supplied in the form of a roll. (JIS K6900) In general, the term “sheet” refers to a product that is thin according to the definition in JIS, and whose thickness is small for the length and width but flat. However, since the boundary between the sheet and the film is not clear and it is not necessary to distinguish the two in terms of the present invention, in the present invention, even when the term “film” is used, the term “sheet” is included and the term “sheet” is used. In some cases, “film” is included.

  The molding method of the injection-molded body is not particularly limited, and for example, an injection molding method such as a general injection molding method for a thermoplastic resin, a gas assist molding method, and an injection compression molding method can be employed. In addition to the above methods, an in-mold molding method, a gas press molding method, a two-color molding method, a sandwich molding method, or the like can be employed in accordance with other purposes.

  The molded article of the present invention has a low photoelastic coefficient and is excellent in transparency, heat resistance, and impact resistance. Therefore, the use of the molded article of the present invention is not particularly limited. It can be used for various lenses such as a pickup lens for optical disks, light guide plates for liquid crystal displays, various optical films and sheets, optical disks, condenser films and the like.

Examples are shown below, but the present invention is not limited by these. In addition, the result shown in an Example evaluated by the following method.
In addition, the various measured value and evaluation about the raw material and test piece which are displayed in this specification were performed as follows. Here, the flow direction from the extruder of the film is called the vertical direction, and the orthogonal direction is called the horizontal direction.

(1) Viscosity average molecular weight (Mv)
Using an Ubbelohde viscometer, a methylene chloride solution (0.6 g / dl) of a polycarbonate resin sample was prepared, and η _sp at 20 ° C. was measured. From the following formulas (I) and (II), the viscosity average molecular weight (Mv )
η _sp /C=[η]×(1+0.28η _sp) (I)
[Η] = 1.23 × 10 ⁻⁴ × (Mv) ^0.83 (II)
(In the formula (I), η _sp is the specific viscosity measured at 20 ° C. in methylene chloride of the polycarbonate resin sample, and C is the concentration of this methylene chloride solution. As the methylene chloride solution, the concentration of the polycarbonate resin sample is (Use a 0.6 g / dl solution.)

(2) Reduced viscosity
The reduced viscosity of the polycarbonate resin sample was measured at a temperature of 20.0 ° C. ± 0.1 ° C. using an Ubbelohde viscometer with a DT-504 automatic viscometer manufactured by Chuo Rika Co., Ltd., using methylene chloride as a solvent. The concentration was measured after being precisely adjusted to 0.60 g / dl.
From the passage time t _{0 of the} solvent and the passage time t of the solution, the following formula:
η _rel = t / t ₀
More he seeks relative viscosity eta _rel, from the relative viscosity eta _rel, the formula:
η _sp = (η−η ₀ ) / η ₀ = η _rel −1
The specific viscosity η _sp was determined.
Dividing the specific viscosity η _sp by the concentration c (g / dl), the following formula:
η _red = η _sp / c
From this, the reduced viscosity (converted viscosity) η _red was determined.
The higher this number, the greater the molecular weight.

(3) Glass transition temperature Temperature distribution of dynamic viscoelasticity using a viscoelastic spectrometer DVA-200 (made by IT Measurement & Control Co., Ltd.) at a strain of 0.1%, a frequency of 10 Hz, and a heating rate of 3 ° C./min. Measurement (dynamic viscoelasticity measurement of JIS K7198A method) was performed. The temperature showing the peak of the main dispersion of loss tangent (tan δ) was defined as the glass transition temperature.

(4) Photoelastic coefficient Using KOBRA-WR manufactured by Oji Scientific Instruments Co., Ltd., a sample of width 15 mm × length 60 mm × thickness 0.2 mm is set so that the slow axis side is in the tensile direction, and the tensile load is 50 gf at a time. The change in phase difference when increasing was measured, and the result was linearly approximated to calculate the slope. Subsequently, the photoelastic coefficient was calculated using the following formula.
“Photoelastic coefficient” = “Slope” × 1.5 × 10 ⁻⁸ /9.8 (Pa ⁻¹ )
A photoelastic coefficient of 7 × 10 ⁻¹¹ Pa ⁻¹ or less was accepted.

(5) Total light transmittance, haze (cloudiness value)
Based on JIS K7105, total light transmittance and diffuse transmittance were measured, and haze was calculated by the following formula. A sample having a total light transmittance of 80% or more and a haze of 5% or less at a thickness of 1 mm was regarded as acceptable.
[Haze] = [diffuse transmittance] / [total light transmittance] × 100

(6) Impact resistance (Izod impact strength)
Based on JIS K-7110, No. 2 A test piece (notched, length 64 mm x width 12.7 mm x thickness 4 mm) was prepared, and Izod impact strength at 23 ° C using JISL-D manufactured by Toyo Seiki Seisakusho Was measured. An Izod impact strength of 15 kJ / m ² or more was accepted.

(7) Heat resistance (deflection temperature under load)
Based on JIS K-7191A method, the test piece of length 80mm x width 10mm x thickness 4mm was produced, and the deflection temperature under load was measured using Toyo Seiki Co., Ltd. S-3M. The measurement was performed under the conditions of a flatwise direction and a bending stress of 0.45 MPa applied to the test piece. Those with a deflection temperature under load of 70 ° C. or higher were considered acceptable.

[Aliphatic polycarbonate resin (A)]
PC1:
Structural unit derived from isosorbide / Structural unit derived from 1,4-cyclohexanedimethanol = 30/70 mol%,
Glass transition temperature = 80 ° C., reduced viscosity 0.69 dl / g
PC2:
Structural unit derived from isosorbide / Structural unit derived from 1,4-cyclohexanedimethanol = 40/60 mol%,
Glass transition temperature = 90 ° C., reduced viscosity 0.69 dl / g
PC3:
Structural unit derived from isosorbide / Structural unit derived from 1,4-cyclohexanedimethanol = 50/50 mol%,
Glass transition temperature = 101 ° C., reduced viscosity 0.57 dl / g
PC4:
Structural unit derived from isosorbide / Structural unit derived from 1,4-cyclohexanedimethanol = 60/40 mol%,
Glass transition temperature = 110 ° C., reduced viscosity 0.51 dl / g
PC5:
Structural unit derived from isosorbide / Structural unit derived from tricyclodecane dimethanol = 50/50 mol%
Glass transition temperature = 110 ° C., reduced viscosity 0.60 dl / g

[Aromatic polycarbonate resin (B)]
PC6: Iupilon S3000 manufactured by Mitsubishi Engineering Plastics
Glass transition temperature = 150 ° C., reduced viscosity 0.49 dl / g,
Viscosity average molecular weight = 20,000

Example 1
After PC1 and PC6 were dry blended at a mass ratio of 90:10, they were compounded at 240 ° C. using a 40 mmφ small unidirectional twin screw extruder manufactured by Mitsubishi Heavy Industries, and formed into a pellet shape. Samples for various evaluations were produced by injection molding of the obtained pellets using an injection molding machine IS50E (screw diameter 25 mm) manufactured by Toshiba Machine. The main molding conditions are as follows.
1) Temperature conditions: Cylinder temperature (240 ° C) Mold temperature (6 ° C)
2) Injection conditions: Injection pressure (115 MPa) Holding pressure (55 MPa)
3) Measurement conditions: Screw rotation speed (65 rpm) Back pressure (15 MPa)
Table 1 shows the results of measuring the glass transition temperature, photoelastic coefficient, total light transmittance, haze, Izod impact strength, and deflection temperature under load for the obtained sample.

(Example 2)
Samples were prepared and evaluated in the same manner as in Example 1 except that PC1 and PC6 were mixed at a mixing mass ratio of 60:40. The results are shown in Table 1.

(Example 3)
Samples were prepared and evaluated in the same manner as in Example 1 except that PC1 and PC6 were mixed at a mixing mass ratio of 30:70. The results are shown in Table 1.

Example 4
Samples were prepared and evaluated in the same manner as in Example 1 except that PC2 and PC6 were mixed at a mixing mass ratio of 60:40. The results are shown in Table 1.

(Example 5)
Samples were prepared and evaluated in the same manner as in Example 1 except that PC3 and PC6 were mixed at a mixing mass ratio of 60:40. The results are shown in Table 1.

(Comparative Example 1)
Samples were prepared and evaluated in the same manner as in Example 1 except that the fatty polycarbonate resin (A) was not used and only PC6 was used and the mold temperature was 100 ° C. The results are shown in Table 1.

(Comparative Example 2)
Samples were prepared and evaluated in the same manner as in Example 1 except that PC4 and PC6 were mixed at a mixing mass ratio of 60:40. The results are shown in Table 1.

(Comparative Example 3)
Samples were prepared and evaluated in the same manner as in Example 1 except that PC5 and PC6 were mixed at a mixing mass ratio of 60:40. The results are shown in Table 1.

(Comparative Example 4)
In place of the aliphatic polycarbonate resin (A), PCTG24635 (poly (1,4-cyclohexylenedimethylene terephthalate) glycol) manufactured by Eastman Chemical Co. was used, and PCTG24635 and PC6 were mixed at a ratio of 60:40. Samples were prepared and evaluated in the same manner as in Example 1 except that they were mixed. The results are shown in Table 1.

  From Table 1, the molded product of the present invention had a low photoelastic coefficient and excellent transparency, heat resistance, and impact resistance as long as it was within the specified range of the present invention. On the other hand, the comparative examples all had high photoelastic coefficients, and Comparative Examples 2 and 3 were inferior to Examples in terms of transparency and Comparative Examples 2 to 4 in terms of impact resistance. From this, it can be seen that the molded article of the present invention has a low photoelastic coefficient and is excellent in transparency, heat resistance and impact resistance.

Claims (7)

Aliphatic polycarbonate resin (A) including a structural unit (a) derived from a dihydroxy compound having a site represented by the following general formula (1) as a part of the structure and a structural unit (b) derived from cyclohexanedimethanol And a molded body comprising a resin composition mainly comprising a mixture (X) comprising an aromatic polycarbonate resin (B), wherein the mixture (X) has a single glass transition temperature, and the glass The transition temperature is in the range from the glass transition temperature of the aliphatic polycarbonate resin (A) to the glass transition temperature of the aromatic polycarbonate resin (B), and the photoelastic coefficient at a light wavelength of 600 nm is 7 × 10 ^−. A molded body characterized by being ¹¹ Pa ⁻¹ or less.

(However, the site represented by the above general formula (1) unless it is part of _-CH 2 -O-H.) Aliphatic polycarbonate resin (A) including a structural unit (a) derived from a dihydroxy compound having a site represented by the following general formula (1) as a part of the structure and a structural unit (b) derived from cyclohexanedimethanol And a molded product made of a resin composition mainly comprising a mixture (X) made of an aromatic polycarbonate resin (B), wherein the proportion of the (b) in the aliphatic polycarbonate resin (A) is 45. The photoelasticity at a light wavelength of 600 nm is from mol% to 80 mol%, the proportion of the aliphatic polycarbonate resin (A) in the mixture (X) is from 1% by mass to 99% by mass. A molded article having a coefficient of 7 × 10 ⁻¹¹ Pa ⁻¹ or less.

(However, the site represented by the above general formula (1) unless it is part of _-CH 2 -O-H.) The molded article according to claim 1 or 2, wherein the dihydroxy compound is a dihydroxy compound represented by the following general formula (2).

  The molded article according to any one of claims 1 to 3, wherein the proportion of the aliphatic polycarbonate resin (A) in the mixture (X) is 50% by mass or more and 99% by mass or less. .   The molded article according to any one of claims 1 to 4, wherein the aliphatic polycarbonate resin (A) has a glass transition temperature of 75 ° C or higher and 105 ° C or lower. The molded body according to any one of claims 1 to 5, wherein the glass transition temperature of the mixture (X) is 75 ° C or higher and 130 ° C or lower.   The total light transmittance measured based on JIS K7361-1 in thickness 1mm of said molded object is 80% or more, and the haze measured based on JIS K7105 is 5% or less, It is characterized by the above-mentioned. The molded product according to any one of 6 to 6.