JP2006199748A - Method for producing resin composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for producing a resin composition which improves surface smoothness and remarkably improves the failure of filler dispersion (white foreign substances on the surface of a molded article) causing the failure of coating adhesion while maintaining excellent heat resistance, impact resistance and linear expansion coefficient in the polyamide-polyphenylene ether alloy resin reinforced with an inorganic filler, and furthermore remarkably improves the productivity as well on production, and its composition and molded article. <P>SOLUTION: The method for producing a thermoplastic resin composition composed of (a) a polyamide, (B) a polyphenylene ether, and (C) at least two types of wollastonite having different aspect ratios comprises feeding the wollastonite having a smaller aspect ratio together with the polyamide. The composition can be obtained by this method. <P>COPYRIGHT: (C)2006,JPO&amp;NCIPI

Description

The present invention maintains the excellent heat resistance, impact strength, and linear expansion coefficient of polyamide-polyphenylene ether alloy resin reinforced with an inorganic filler, while improving surface smoothness and filler dispersion causing poor coating adhesion. The present invention relates to a method for producing a resin composition in which defects (white foreign matters on the surface of a molded product) are greatly improved and productivity in production is also greatly improved, and the composition and molded product.
The resin composition of the present invention can be used in a wide range of fields such as electric / electronic parts, OA parts, vehicle parts, machine parts, etc., and can be particularly suitably used as an outer plate material for automobiles.

Polyphenylene ether is used in a wide range of applications because it has excellent mechanical properties, electrical properties, and heat resistance, and also has excellent dimensional stability, but it is inferior in molding processability by itself. A technique for blending polyamide has been proposed (see, for example, Patent Document 1), and is currently a material used for a wide variety of applications.
Recently, the use of polyamide-polyphenylene ether alloy resins reinforced with inorganic fillers for automobile exterior materials is rapidly progressing. Examples of the performance required for automobile exterior materials include a low linear expansion coefficient, impact resistance, surface smoothness, filler dispersibility, and the like.
However, in the resin composition containing the inorganic filler, deterioration of surface smoothness, poor dispersion of the filler, and reduction in productivity at the time of manufacture are major issues.

  As a conventional technique, for example, a technique in which a filler selected from GF and / or calcium silicate is mixed with a polyamide in advance (see, for example, Patent Document 2), an inorganic filler having an average particle size of 5 μm or less is previously added to a polyamide. A technique of mixing and blending (for example, see Patent Document 3), a technique of blending ceramic whiskers having an aspect ratio of 10 to 100 with polyamide (for example, see Patent Document 4), an average particle diameter of 1.2 μm or more A technique of blending a plate-like filler of 5 μm or less and / or a fibrous inorganic filler having an average fiber length of 2 μm or more together with polyamide (see, for example, Patent Document 5), an average particle size of 1.2 μm or more and 5 μm or less, and an aspect ratio of 3 or more Resin composition containing a plate-like filler and / or a fibrous inorganic filler having an average fiber length of 2 μm or more For example, refer to Patent Document 6.), The resin compositions incorporating surface treated inorganic filler with a coupling agent (e.g., see Patent Document 7.) Have been disclosed.

In addition, a filler with a small aspect ratio is excellent in surface appearance, but the effect of suppressing the linear expansion coefficient is small, and it is necessary to increase the amount of filler added to reduce the linear expansion coefficient, resulting in impact resistance. There is a problem that the performance is lowered. In addition, a filler having a large aspect ratio is excellent in the effect of suppressing the linear expansion coefficient, but has a problem that surface appearance (particularly surface smoothness) deteriorates, and unevenness is generated on the surface after coating, for example.
In order to achieve both the linear expansion coefficient suppression of the contradictory characteristics and the surface appearance, even when two or more kinds of inorganic fillers having different aspect ratios are used in combination, simply by melt kneading as in the prior art It has become clear that new problems such as generation of white foreign matters due to poor dispersion of the filler occur.
These white foreign substances are those in which the filler itself is exposed on the surface of the molded product without being sufficiently dispersed inside the composition, which causes the paint to be repelled during painting, leading to deterioration of the paintability. There was a need for improvement.

Japanese Patent Publication No. 45-997 Japanese Patent Laid-Open No. 63-101442 JP-A-3-103467 JP 2002-194092 A JP 2002-206054 A JP 2002-194207 A JP 2002-146206 A

  The problem to be solved by the present invention is to improve the surface smoothness and poor coating adhesion while maintaining the excellent heat resistance, impact strength and linear expansion coefficient of polyamide-polyphenylene ether alloy resin reinforced with inorganic filler. By providing a method for producing a resin composition that greatly improves the filler dispersion failure (white foreign matter on the surface of the molded product), and further greatly improves the productivity during production, and the composition and molded product is there.

As a result of investigations to solve the above problems, the inventors of the present invention obtained at least two or more types of wollastonite having different aspect ratios when producing a polyamide-polyphenylene ether alloy resin reinforced with an inorganic filler. Used, wollastonite with a smaller aspect ratio is supplied together with polyamide and melt kneaded to maintain excellent heat resistance, impact strength, and coefficient of linear expansion, while improving surface smoothness and poor paint adhesion The present inventors have found that the filler dispersion failure (white foreign matter on the surface of the molded product) causing the above-mentioned causes can be greatly improved, and that the productivity at the time of production can be greatly improved.
That is, the present invention relates to a method for producing a resin composition comprising (A) polyamide, (B) polyphenylene ether, and (C) at least two or more types of wollastonite having different aspect ratios, wherein the wollastonite has a small aspect ratio. It is related with the manufacturing method of the thermoplastic resin composition characterized by supplying (C-1) with a polyamide. The present invention also relates to a resin composition produced by the production method, and an injection molded product thereof, in particular, a molded product for an automobile outer plate.

  The thermoplastic resin composition of the present invention uses at least two or more types of wollastonite having different aspect ratios when producing a polyamide-polyphenylene ether alloy resin reinforced with an inorganic filler, and further has a low aspect ratio. By supplying the lastite together with polyamide, while maintaining excellent heat resistance, impact strength, and linear expansion coefficient, it improves surface smoothness and poor filler dispersion that causes poor paint adhesion (white surface of the molded product) The foreign matter) has been greatly improved, and the productivity at the time of manufacture has been greatly improved. In particular, it can be suitably used as an outer plate material for automobiles.

Each component which comprises the thermoplastic resin composition which consists of a manufacturing method of this invention is described in detail.
As the type of (A) polyamide that can be used in the present invention, any polyamide having an amide bond {—NH—C (═O) —} in the polymer main chain repeating unit may be used. it can.
In general, polyamides are obtained by ring-opening polymerization of lactams, polycondensation of diamine and dicarboxylic acid, polycondensation of aminocarboxylic acid, and the like, but are not limited thereto.
The diamines are roughly classified into aliphatic, alicyclic and aromatic diamines. Specific examples include tetramethylene diamine, hexamethylene diamine, undecamethylene diamine, dodecamethylene diamine, tridecamethylene diamine, 2, 2 , 4-trimethylhexamethylenediamine, 2,4,4-trimethylhexamethylenediamine, 5-methylnanomethylenediamine, 1,3-bisaminomethylcyclohexane, 1,4-bisaminomethylcyclohexane, m-phenylenediamine, p -Phenylenediamine, m-xylylenediamine, p-xylylenediamine and the like.

Dicarboxylic acids are roughly classified into aliphatic, alicyclic and aromatic dicarboxylic acids. Specific examples include adipic acid, suberic acid, azelaic acid, sebacic acid, dodecanedioic acid, 1,1,3-tridecane. Examples include diacid, 1,3-cyclohexanedicarboxylic acid, terephthalic acid, isophthalic acid, naphthalenedicarboxylic acid, dimer acid and the like.
Specific examples of lactams include ε-caprolactam, enantolactam, and ω-laurolactam.
Specific examples of aminocarboxylic acids include ε-aminocaproic acid, 7-aminoheptanoic acid, 8-aminooctanoic acid, 9-aminononanoic acid, 11-aminoundecanoic acid, 12-aminododecanoic acid, and 13-aminotriic acid. Examples include decanoic acid.
In the present invention, any of copolyamides obtained by polycondensation of these lactams, diamines, dicarboxylic acids, and ω-aminocarboxylic acids alone or in a mixture of two or more types can be used.
Further, those obtained by polymerizing these lactams, diamines, dicarboxylic acids, and ω-aminocarboxylic acids up to a low molecular weight oligomer stage in a polymerization reactor and increasing the molecular weight in an extruder or the like can be suitably used.

Particularly, polyamides that can be usefully used in the present invention include polyamide 6, polyamide 6,6, polyamide 4,6, polyamide 11, polyamide 12, polyamide 6,10, polyamide 6,12, polyamide 6 / 6,6, Polyamide 6/6, polyamide 6 / MXD (m-xylylenediamine), polyamide 6, T, polyamide 6, I, polyamide 6/6, T, polyamide 6/6, I, polyamide 6,6 / 6 T, polyamide 6,6 / 6, I, polyamide 6/6, T / 6, I, polyamide 6,6 / 6, T / 6, I, polyamide 6/12/6, T, polyamide 6,6 / 12 / 6, T, polyamide 6/12/6, I, polyamide 6, 6/12/6, I, etc., and polyamides obtained by copolymerizing a plurality of polyamides with an extruder or the like can also be used. Can.
Preferred polyamides are polyamide 6, polyamide 6,6, polyamide 6 / 6,6, polyamide 6,12, polyamide 6,6 / 6, I or a mixture thereof, more preferably polyamide 6,6, polyamide 6 Or a blend of polyamide 6,6 and polyamide 6, polyamide 6,6 and polyamide 6,6 / 6, I, more preferably a blend of polyamide 6,6 and polyamide 6,6 / 6, I .

In order to suppress a decrease in impact properties of the composition, the relative viscosity of the polyamide used in the present invention is desirably 2.0 or more.
In addition, the relative viscosity as used in the field of this invention is the value measured based on JISK6920-1: 2000. Specifically, polyamide was dissolved in 98% concentrated sulfuric acid at a concentration of 1 g / 100 cm ³ , and the flow time measured at 25 ° C. with an Ostwald viscometer was t ₁ , the flow of 98% concentrated sulfuric acid alone at 25 ° C. Let time be t ₀
ηr = t ₁ / t ₀
This is the value indicated by.

In the present invention, when the polyamide is used as a mixture, the relative viscosity is measured by separating the polyamide component contained in the composition or measuring the ηr of the polyamide component used as a raw material (1 g / 100 cm ³ ). As a solution of the above, it is possible to know by a method of actually measuring a mixed solution obtained by mixing them according to the mixing ratio.
The terminal group of the polyamide generally has an amino group and a carboxyl group, and a preferable ratio is a carboxyl group / amino group concentration ratio of 6/4 to 9/1, more preferably 7/3 to 8/2. It is.
As a method for adjusting the end groups of these polyamides, a known method as will be apparent to those skilled in the art can be used. For example, a method of adding diamines, dicarboxylic acids, monocarboxylic acids or the like so that a predetermined terminal concentration is obtained at the time of polymerization of polyamide, or a method of adjusting by a mixture of two or more kinds of polyamides having different terminal group ratios, etc. It is done.
In addition, a metal stabilizer as described in JP-A-1-163262, which has been publicly known for the purpose of improving the heat resistance stability of polyamide, can be used without any problem.

Among these metal stabilizers, those which can be particularly preferably used include CuI, CuCl ₂ , copper acetate, cerium stearate and the like. Also, alkali metal halide salts represented by potassium iodide, potassium bromide and the like can be suitably used. Of course, these may be added together.
A preferred blending amount of the metal stabilizer and / or alkali metal halide salt is 0.001 to 1 part by mass with respect to 100 parts by mass of the polyamide as a total amount.
Furthermore, in addition to the above, known additives that can be added to the polyamide may be added in an amount of less than 10 parts by mass with respect to 100 parts by mass of the polyamide.
The (B) polyphenylene ether that can be used in the present invention is a homopolymer and / or copolymer comprising the structural unit of the formula (1).

[Wherein O is an oxygen atom, R is independently hydrogen, halogen, primary or secondary lower alkyl, phenyl, haloalkyl, aminoalkyl, hydrocarbonoxy, or halohydrocarbonoxy (provided that At least two carbon atoms separating the halogen atom and the oxygen atom). ]

  Specific examples of the polyphenylene ether of the present invention include, for example, poly (2,6-dimethyl-1,4-phenylene ether), poly (2-methyl-6-ethyl-1,4-phenylene ether), poly (2-methyl-6-phenyl-1,4-phenylene ether), poly (2,6-dichloro-1,4-phenylene ether) and the like, and 2,6-dimethylphenol and other phenols (For example, a copolymer with 2,3,6-trimethylphenol or a copolymer with 2-methyl-6-butylphenol as described in Japanese Patent Publication No. 52-17880). Also included are polyphenylene ether copolymers.

Among these, particularly preferred polyphenylene ether is poly (2,6-dimethyl-1,4-phenylene ether), a copolymer of 2,6-dimethylphenol and 2,3,6-trimethylphenol, or a mixture thereof. It is.
The production method of the polyphenylene ether used in the present invention is not particularly limited, and known methods can be used. For example, U.S. Pat. Nos. 3,306,874, 3,306,875, 3,257,357, and Examples include the production methods described in Japanese Patent No. 3257358, JP-A-50-51197, and JP-A-63-152628.

The reduced viscosity of the polyphenylene ether that can be used in the present invention (ηsp / c: 0.5 g / dl, chloroform solution, measured at 30 ° C.) is preferably in the range of 0.15 to 0.70 dl / g, More preferably, it is the range of 0.20-0.60 dl / g, More preferably, it is the range of 0.40-0.55 dl / g.
In the present invention, even a blend of two or more polyphenylene ethers having different reduced viscosities can be used without any problem. For example, a mixture of a polyphenylene ether having a reduced viscosity of 0.45 dl / g or less and a polyphenylene ether having a reduced viscosity of 0.50 dl / g or more, a low molecular weight polyphenylene ether having a reduced viscosity of 0.40 dl / g or less, and a reduced viscosity of 0.50 dl / g or more. A mixture of polyphenylene ethers, etc., of course, is, of course, not limited to these.

In addition, the polyphenylene ether that can be used in the present invention may be a polyphenylene ether modified in whole or in part.
The modified polyphenylene ether here means at least one carbon-carbon double bond or triple bond and at least one carboxylic acid group, acid anhydride group, amino group, hydroxyl group, or glycidyl in the molecular structure. The polyphenylene ether modified with at least one modifying compound having a group.
The method for producing the modified polyphenylene ether includes (1) a modified compound without melting the polyphenylene ether at a temperature in the range of 100 ° C. or higher in the presence or absence of a radical initiator and lower than the glass transition temperature of the polyphenylene ether. (2) A method in which polyphenylene ether and a modifying compound are melt-kneaded and reacted at a temperature in the range of the glass transition temperature of polyphenylene ether to 360 ° C. in the presence or absence of a radical initiator, ( 3) A method of reacting a polyphenylene ether and a modifying compound in a solution at a temperature lower than the glass transition temperature of the polyphenylene ether in the presence or absence of a radical initiator may be mentioned. , (1) and (2) are preferred.

Next, at least one modified compound having at least one carbon-carbon double bond or triple bond and at least one carboxylic acid group, acid anhydride group, amino group, hydroxyl group, or glycidyl group in the molecular structure Will be described in detail.
Examples of modified compounds having a carbon-carbon double bond, a carboxylic acid group, and an acid anhydride group in the molecule include maleic acid, fumaric acid, chloromaleic acid, cis-4-cyclohexene-1,2-dicarboxylic acid, and these And acid anhydrides. Fumaric acid, maleic acid, and maleic anhydride are particularly preferable, and fumaric acid and maleic anhydride are particularly preferable.
In addition, one in which one or two of the carboxyl groups of the unsaturated dicarboxylic acid is an ester can be used.

Examples of the modified compound having both a carbon-carbon double bond and a glycidyl group in the molecule include allyl glycidyl ether, glycidyl acrylate, glycidyl methacrylate, and epoxidized natural fats and oils.
Among these, glycidyl acrylate and glycidyl methacrylate are particularly preferable.
Examples of the modified compound having a carbon-carbon double bond and a hydroxyl group in the molecule include general formulas C _n H _2n-3 such as allyl alcohol, 4-penten-1-ol, 1,4-pentadien-3-ol and the like. Examples thereof include unsaturated alcohols of OH (n is a positive integer) and unsaturated alcohols such as general formulas C _n H _2n-5 OH and C _n H _2n-7 OH (n is a positive integer).

The above-described modifying compounds may be used alone or in combination of two or more.
The amount of the modifying compound added when producing the modified polyphenylene ether is preferably 0.1 to 10 parts by mass, more preferably 0.3 to 5 parts by mass with respect to 100 parts by mass of the polyphenylene ether.
A preferable amount of the radical initiator when producing the modified polyphenylene ether using the radical initiator is 0.001 to 1 part by mass with respect to 100 parts by mass of the polyphenylene ether.

Further, the addition rate of the modifying compound in the modified polyphenylene ether is preferably 0.01 to 5% by mass. More preferably, it is 0.1-3 mass%.
In the modified polyphenylene ether, an unreacted modified compound and / or a polymer of the modified compound may remain.
A styrene-based thermoplastic resin may be blended as long as the amount is less than 50 parts by mass with respect to 100 parts by mass of the total amount of polyphenylene ether. Examples of the styrenic thermoplastic resin in the present invention include homopolystyrene, rubber-modified polystyrene (HIPS), styrene-acrylonitrile copolymer (AS resin), styrene-rubbery polymer-acrylonitrile copolymer (ABS resin), and the like. Can be mentioned.

Furthermore, you may add the well-known additive etc. which can be added to polyphenylene ether in the quantity of less than 10 mass parts with respect to 100 mass parts of polyphenylene ether.
The (W) wollastonite that can be used in the present invention is generally a refined, ground and classified natural mineral mainly composed of calcium silicate, but an artificially synthesized one can also be used.
As a substitute for glass fiber, wollastonite having a large particle diameter with an average fiber diameter of 40 μm and an average fiber length of 600 μm is widely used. In the present invention, a wollastonite having a smaller particle diameter is preferable. Further, it is necessary to use at least two types of wollastonite having different aspect ratios.

Among at least two or more types of wollastonite having different aspect ratios, the wollastonite (C-1) having a small aspect ratio has an aspect ratio of less than 8 and an average particle diameter of 2 to 9 μm, preferably Those having an aspect ratio of 6 or less and an average particle diameter of 3 to 7 μm, more preferably those having an aspect ratio of 6 or less and an average particle diameter of 3 to 5 μm can be used. In order to suppress the deterioration of the surface appearance, the aspect ratio of (C-1) is preferably less than 8.
The wollastonite (C-2) having a large aspect ratio has an aspect ratio of 8 or more and an average particle diameter of 2 to 11 μm, preferably an aspect ratio of 10 or more and an average particle diameter of 3 to 10 μm. Those having an aspect ratio of 12 or more and an average particle diameter of 3 to 10 μm can be used.

In order to suppress the deterioration of the linear expansion coefficient, it is preferable that the aspect ratio of (C-2) is 8 or more and the average particle diameter is 2 μm or more. Moreover, in order to suppress the deterioration of the surface appearance, it is preferable that the average particle diameter of (C-2) is 11 μm or less.
The average particle diameter of wollastonite as used in the present invention means adding 0.75 g of wollastonite to 45 ml of 0.05% Calgon solution using a Sedigraph particle size analyzer (Micromeritics Instruments, model 5100) It is measured after sufficiently dispersing in a sonic bath, and the calculated equivalent sphere diameter is shown.
The aspect ratio is calculated from the values obtained by measuring the diameter and length of at least 5000 wollastonite particles with a scanning electron microscope (SEM).

Moreover, what used the surface treating agent can also be used for the wollastonite which can be used by this invention. Specific examples of the surface treatment agent include those acting as a dispersant represented by stearic acid, oleic acid, palmitic acid, magnesium stearate, calcium stearate, aluminum stearate, stearamide, stearic acid ethyl ester, What plays the role of a coupling agent represented by a silane system, a titanate system, an aluminum system, a zirconium system etc. can be used if needed.
The preferable usage-amount in that case is the range of 0.05 mass%-1.5 mass% with respect to wollastonite.
In the component (C), the ratio of (C-1) and (C-2) is preferably (C-1) / (C-2) of 7/3 to 1/9, more preferably 6/4. ~ 2/8.

The blending ratio of each component in the thermoplastic resin composition obtained by the production method of the present invention is 100 parts by mass in total of (A) 40 to 80% by mass of polyamide and (B) 20 to 60% by mass of polyphenylene ether resin. (C) 10-50 parts by mass of wollastonite. More preferably, (C) Wollastonite is 15 to 40 parts by mass with respect to 100 parts by mass in total of (A) 45 to 75% by mass of polyamide and (B) 25 to 55% by mass of polyphenylene ether resin.
The conductive material (D) that can be used in the present invention is at least one selected from the group consisting of conductive carbon black, carbon fibrils, and carbon nanotubes.
Examples of the conductive carbon black include carbon black described as a conductive carbon black in WO01 / 081473. Examples of commercially available conductive carbon blacks include Ketjen Black EC and Ketjen Black EC600JD available from Ketjen Black International. Moreover, as a carbon fibril, the fine carbon fiber etc. which are described in the international publication patent WO94 / 023433 are mentioned. Commercially available carbon fibrils include BN fibrils available from Hyperion Catalyst International.

  The preferable addition form of the conductive material used in the present invention is to add it in the form of a masterbatch premixed in one or more kinds of resins selected from polyphenylene ether, polyamide and block copolymer. Preferably, it is a method of adding in the form of a masterbatch premixed with polyamide. There is no particular limitation on the mixing method at that time, but melt kneading using an extruder is most preferable. More preferably, using a co-rotating twin-screw extruder having two or more supply ports set at 250 to 300 ° C., after supplying and melting and kneading the resin from the upstream supply port, from the downstream supply port The method of supplying carbon and melt-kneading is mentioned. At this time, the resin temperature is more preferably less than 340 ° C. The preferable compounding amount of carbon in the master batch is 5 to 30% by mass. More preferably, it is 8-25 mass%.

A commercially available master batch may be used. Examples of commercially available master batches include polyamide 66 / carbon fibril master batch (trade name: Polyamide 66 with Fiber ^™ Nanotubes RMB4620-00: carbon fibril content 20%) available from Hyperion Catalyst International.
In the present invention, an impact modifier may be used. In this case, the impact modifier that can be used is a polymer block mainly composed of an aromatic vinyl compound and a heavy polymer composed mainly of a conjugated diene compound. It is at least one selected from the group consisting of an aromatic vinyl compound-conjugated diene compound block copolymer composed of a combined block, a hydrogenated product thereof, and an ethylene-α-olefin copolymer.

The “mainly” in the polymer block mainly composed of the aromatic vinyl compound as used herein refers to a block in which at least 50% by mass or more of the block is an aromatic vinyl compound. More preferably, it is 70 mass% or more, More preferably, it is 80 mass% or more, Most preferably, it is 90 mass% or more. The same applies to “mainly” in a polymer block mainly composed of a conjugated diene compound, and refers to a block in which at least 50% by mass or more is a conjugated diene compound. More preferably, it is 70 mass% or more, More preferably, it is 80 mass% or more, Most preferably, it is 90 mass% or more.
In this case, for example, even in the case of a block in which a small amount of a conjugated diene compound or other compound is randomly bonded in the aromatic vinyl compound block, 50% by mass of the block is formed from the aromatic vinyl compound. Thus, it is regarded as a block copolymer mainly composed of an aromatic vinyl compound. The same applies to the case of a conjugated diene compound.

Specific examples of the aromatic vinyl compound that can be used in the aromatic vinyl compound-conjugated diene compound block copolymer in the present invention include styrene, α-methylstyrene, vinyltoluene, and the like. More than one kind of compound is used, and styrene is particularly preferable among them.
Specific examples of the conjugated diene compound include butadiene, isoprene, piperylene, 1,3-pentadiene, etc., and one or more compounds selected from these are used, and among them, butadiene, isoprene and combinations thereof. Is preferred.
The microstructure of the soft segment portion of the conjugated diene compound of the block copolymer is preferably 1,2-vinyl content or the total amount of 1,2-vinyl content and 3,4-vinyl content of 5-80%, 10 to 50% is preferable, and 10 to 40% is most preferable.

In the block copolymer of the present invention, the polymer block [A] mainly composed of an aromatic vinyl compound and the polymer block [B] mainly composed of a conjugated diene compound are AB type, ABA type, A block copolymer having a bond type selected from A-B-A-B type is preferable. Of course, a mixture thereof may be used.
Among these, the ABA type and the ABBA type are more preferable. Of course, these may be a mixture.
The block copolymer of an aromatic vinyl compound and a conjugated diene compound that can be used in the thermoplastic resin composition obtained by the production method of the present invention is more preferably a hydrogenated block copolymer. . The hydrogenated block copolymer is an aliphatic double bond of a polymer block mainly composed of a conjugated diene compound by subjecting the block copolymer of the aromatic vinyl compound and the conjugated diene compound to a hydrogenation treatment. Is controlled in the range of more than 0 and 100%. A preferable hydrogenation rate of the hydrogenated block copolymer is 50% or more, more preferably 80% or more, and most preferably 98% or more.

These block copolymers can be used without any problem as a mixture of a non-hydrogenated block copolymer and a hydrogenated block copolymer.
These block copolymers of aromatic vinyl compound-conjugated diene compound are different in bond type, different in aromatic vinyl compound type, different in conjugated diene compound type, unless otherwise contrary to the spirit of the present invention, Used with a mixture of 2-bond vinyl content or 1,2-bond vinyl content different from 3,4-bond vinyl content, different aromatic vinyl compound component content, or different hydrogenation rate It doesn't matter.

  More preferred specific examples are illustrated based on a hydrogenated product of a block copolymer comprising a polymer block mainly composed of an aromatic vinyl compound and a polymer block mainly composed of a conjugated diene compound. A block copolymer having a content of a polymer block mainly composed of an aromatic vinyl compound in an amount of 60% by mass to 90% by mass, and a polymer block mainly composed of an aromatic vinyl compound in the block copolymer Examples include a mixture having a content of 20% by mass or more and less than 60% by mass. Moreover, in the block copolymer used for the thermoplastic resin composition obtained by the production method of the present invention, a mixture obtained by premixing oil mainly composed of paraffin may be used. The processability of the resin composition can be improved by preliminarily mixing oil mainly composed of paraffin. The amount of the oil mainly composed of paraffin at this time is 1 to 70 parts by mass with respect to 100 parts by mass of the block copolymer. When 70 parts by mass or more is mixed, the handleability is poor.

The oil mainly composed of paraffin here is a mixture of a hydrocarbon compound having a weight average molecular weight of 500 to 10,000, which is a combination of an aromatic ring-containing compound, a naphthene ring-containing compound, and a paraffinic compound. Yes, the paraffinic compound content is 50% by mass or more. More preferably, the paraffinic compound is 50 to 90% by mass, the naphthene ring-containing compound is 10 to 40% by mass, and the aromatic ring-containing compound is 5% by mass or less.
These oils mainly composed of paraffin are commercially available, and examples thereof include PW380 manufactured by Idemitsu Kosan Co., Ltd.
As an ethylene-α-olefin copolymer that can be used in the thermoplastic resin composition of the present invention, ethylene-α-produced with a single-site catalyst as described in JP-A-2001-302911. An olefin copolymer can be preferably used.

Moreover, the impact improving material used for the thermoplastic resin composition obtained by the production method of the present invention may be an impact improving material modified in whole or in part.
As used herein, a modified impact modifier is at least one carbon-carbon double bond or triple bond and at least one carboxylic acid group, acid anhydride group, amino group, hydroxyl group in the molecular structure, or It refers to an impact modifier modified with at least one modifying compound having a glycidyl group.
The method for producing the modified impact modifier is as follows: (1) In the presence or absence of a radical initiator, the impact modifier and the modifying compound at a temperature in the range of the softening point temperature of the impact modifier to 250 ° C. or less. (2) a method of reacting an impact modifier and a modifying compound in a solution at a temperature below the softening point of the impact modifier in the presence or absence of a radical initiator, and (3) Examples include a method in which the impact modifier and the modifying compound are reacted without melting at a temperature below the softening point of the impact modifier in the presence or absence of a radical initiator, and any of these methods may be used. The method (1) is preferable, and the method (1) is most preferably performed in the presence of a radical initiator.

At least one modification having at least one carbon-carbon double bond or triple bond and at least one carboxylic acid group, acid anhydride group, amino group, hydroxyl group, or glycidyl group in the molecular structure referred to herein. As the compound, the same modified compounds described for the modified polyphenylene ether can be used.
Moreover, you may add a compatibilizer to the thermoplastic resin composition obtained by the manufacturing method of this invention in the case of manufacture of a composition. The main purpose of using the compatibilizer is to improve the physical properties of the polyamide-polyphenylene ether mixture. The compatibilizing agent that can be used in the present invention refers to a polyfunctional compound that interacts with polyphenylene ether, polyamide, or both.
In any case, it is desirable that the resulting polyamide-polyphenylene ether mixture exhibits improved compatibility.

Examples of the compatibilizing agent that can be used in the thermoplastic resin composition of the present invention are described in detail in JP-A-8-48869 and JP-A-9-124926, and these known phases are described. All the solubilizers can be used and can be used in combination.
Among these various compatibilizing agents, examples of particularly suitable compatibilizing agents include maleic acid, maleic anhydride, and citric acid, and maleic anhydride is most preferred.
The preferable amount of the compatibilizing agent that can be used in the present invention is 0.1 to 20 parts by mass, more preferably 0.1 to 10 parts by mass with respect to 100 parts by mass of the mixture of polyamide and polyphenylene ether. .

In the present invention, in addition to the above-described components, additional components may be added as necessary within a range not impairing the effects of the present invention.
Examples of additional components are listed below.
Other thermoplastic resins such as polyester and polyolefin, inorganic fillers (talc, kaolin, zonotlite, titanium oxide, potassium titanate, glass fibers, etc.), known adhesion improvements to increase the affinity between inorganic fillers and resins Agents, flame retardants (halogenated resins, silicone flame retardants, magnesium hydroxide, aluminum hydroxide, organic phosphate compounds, ammonium polyphosphate, red phosphorus, etc.), fluorine-based polymers that exhibit the anti-dripping effect, plasticizers ( Oil, low molecular weight polyolefin, polyethylene glycol, fatty acid esters, etc.) and flame retardant aids such as antimony trioxide, carbon black for coloring, antistatic agents, various peroxides, zinc oxide, zinc sulfide, antioxidants, UV absorbers, light stabilizers and the like.

The specific addition amount of these components is the range which does not exceed 100 mass parts in total with respect to 100 mass parts of polyamide, polyphenylene ether, and the total amount of an impact modifier. A specific processing machine for obtaining the thermoplastic resin composition of the present invention includes supply ports in an upstream portion (first supply port), a midstream portion (second supply port), and a downstream portion (third supply port). A twin screw extruder is preferred.
Furthermore, the L / D of the twin screw extruder used in the present invention needs to be 38 or more and 70 or less. Preferably it is L / D38 or more and 65 or less, More preferably, it is L / D40 or more and 55 or less. In order to ensure the dispersibility of each component (particularly wollastonite) in the thermoplastic resin composition of the present invention and obtain the desired performance, it is preferable to use a twin screw extruder having L / D of 38 or more.

The melt kneading temperature at this time is not particularly limited, but the conditions under which a suitable composition can be usually obtained can be arbitrarily selected from 240 to 360 ° C.
As a method for producing a thermoplastic resin composition in the present invention, a twin-screw extruder provided with supply ports in an upstream portion (first supply port), a middle flow portion (second supply port), and a downstream portion (third supply port) A specific production method when using is exemplified below.
1. After supplying polyphenylene ether and / or impact modifier from the first supply port and melt-kneading, supply polyamide, low wollastonite with a low aspect ratio, and wollastonite with a high aspect ratio from the second supply port, How to smelt,
2. After supplying polyphenylene ether and / or impact modifier from the first supply port and melt-kneading, a part of the polyamide is supplied from the second supply port and melt-kneaded, and the remaining polyamide and aspect ratio are further supplied from the third supply port. Low wollastonite, a method of supplying and melting kollastonite with a large aspect ratio,
3. After supplying polyphenylene ether and a part of wollastonite having a small aspect ratio and / or impact modifier from the first supply port and melt-kneading, the polyamide and the remaining wollastonite having a small aspect ratio are supplied from the second supply port. A method of supplying and melt-kneading, further supplying wollastonite having a larger aspect ratio than the third supply port, and melt-kneading,
4). Polyphenylene ether and / or impact modifier is supplied from the first supply port and melt-kneaded, then polyamide and a wollastonite having a low aspect ratio are supplied from the second supply port, melt-kneaded, and the aspect is further supplied from the third supply port. A method in which wollastonite having a large ratio is supplied and melt-kneaded is desirable. Among them, the method 3 or 4 is preferable, and the method 4 is particularly preferable.

The wollastonite having a small aspect ratio supplied together with the polyamide may be supplied to the extruder in the form of a masterbatch dispersed in the polyamide supplied together. The amount of wollastonite in the master batch in this case is 20 to 50% by mass when the master pellet is 100% by mass.
The thermoplastic resin composition of the present invention thus obtained can be molded as molded parts of various parts by various conventionally known methods such as injection molding.

These various parts include, for example, IC tray materials, chassis of various disk players, electrical / electronic parts such as cabinets, OA parts and machine parts such as various computers and peripheral devices, motorcycle cowls, and automobile fenders. , Door panel, front panel, rear panel, rocker panel, rear bumper panel, back door garnish, emblem garnish, fuel inlet panel, over fender, outer door handle, door mirror housing, bonnette air intake, bumper, bumper guard, roof rail, Various aero parts such as roof rail legs, pillars, pillar covers, wheel covers, spoilers, exterior parts such as various malls and emblems, instrument panels , It can be suitably used for interior parts typified by console box, trims and the like.
Among these, it can be used suitably for the outer plate | board component of a motor vehicle, and can be used suitably especially for a rear panel.

EXAMPLES Hereinafter, although an Example and a comparative example demonstrate this invention further in detail, this invention is not limited to what was shown by this Example.
(Raw materials used)
The raw materials used in Examples and the like are as follows.
(A) Polyamide (hereinafter abbreviated as PA)
(PA-1) Polyamide 6
Product name: UBE nylon 1011FB, manufactured by Ube Industries, Ltd.
(PA-2) Polyamide 6,6
Product name: Leona 1200-011 manufactured by Asahi Kasei Chemicals Corporation
(PA-3) Polyamide 6,6 / 6I
1.90 kg of equimolar salt of adipic acid and hexamethylene dian, 0.40 kg of equimolar salt of isophthalic acid and hexamethylene diamine, 0.2 kg of ε-capulactam, 0.10 kg of adipic acid, 29 g of copper iodide, potassium iodide 480 g and 2.5 kg of pure water were charged into a 5 L autoclave and stirred well. After sufficient N ₂ substitution, the temperature was raised from room temperature to 220 ° C. over about 1 hour with stirring. Under the present circumstances, although the internal pressure became 18 kg / cm < ² > -G by the natural pressure by the water vapor | steam in an autoclave, it continued further heating, removing water out of a reaction system so that it might not become a pressure more than 18 kg / cm < ² > -G. When the internal temperature reached 260 ° C. after 2 hours, the heating was stopped, the autoclave discharge valve was closed, and the system was cooled to room temperature over about 8 hours. After cooling, the autoclave was opened, and about 2 kg of polymer was taken out and ground. The obtained pulverized polymer was placed in a 10 L evaporator and subjected to solid phase polymerization at 200 ° C. for 10 hours under a N ₂ stream. The polyamide obtained by solid phase polymerization contained 14.0 mol% of hexamethyleneisophthalamide units. This polyamide contained 96 ppm of copper element, and the molar ratio of the copper-containing component and the iodine-containing component was 19.

(B) Polyphenylene ether (hereinafter abbreviated as PPE)
Poly (2,6-dimethyl-1,4-phenylene ether) (Asahi Kasei Chemicals Corporation)
(PPE-1) polyphenylene ether Reduced viscosity: 0.52 dl / g (0.5 g / dl, chloroform solution, measured at 30 ° C.)
(PPE-2) Maleic anhydride-modified polyphenylene ether Reduced viscosity: 0.1 parts by mass of radical initiator and 1.5 parts by mass of maleic anhydride are added to 100 parts by mass of PPE of 0.52 dl / g, and biaxial It was prepared by melt kneading at a cylinder temperature of 320 ° C. using an extruder. The addition rate of maleic anhydride was 0.5%.

(C-1) Wollastonite with a small aspect ratio (Filler-1) Product name: NYAD1250 manufactured by NYCO
Average particle size = 4 μm, aspect ratio = 3
(C-2) Wollastonite with large aspect ratio (Filler-2) Product name: NYGLOS5
Average particle size = 5 μm, aspect ratio = 13
(Filler-3) NYCO product name: NYGLOS12
Average particle size = 12 μm, aspect ratio = 13
(Filler-4) Made by NYCO Product name: NYGLOS5
Average particle size = 5 μm, aspect ratio = 13
Surface treatment: aminosilane compound (0.5% by mass)

(D) Conductive material (PA / KB-MB)
90 parts by mass of polyamide 6,6 (Leona 1200-011: manufactured by Asahi Kasei Chemicals) and 10 parts by mass of conductive carbon black (Ketjen Black EC600-JD: manufactured by Ketjen Black International) are biaxially extruded. The mixture was melt-kneaded with a machine to obtain a conductive masterbatch.
(Impact modifier)
(SEBS-1) Polystyrene-hydrogenated polybutadiene-polystyrene
Number average molecular weight = 246,000
Total content of styrene components = 33%

(Measuring method)
The measurement method will be described below.
<Izod impact strength>
The resin composition pellets obtained in the examples and comparative examples were dried at 80 ° C. for 3 hours and then injected with a Toshiba IS-80EPN molding machine (cylinder temperature 290 ° C., mold temperature set at 80 ° C.) with an injection time of 20 A 1/8 inch strip test piece was prepared at a cooling time of 20 seconds, and the test was performed.
It calculated | required based on ASTM-D-256. (Notched, 1/8 inch thick)
<Linear expansion coefficient>
The resin composition pellets obtained in the examples and comparative examples were dried at 80 ° C. for 3 hours and then injected with a Toshiba IS-80EPN molding machine (cylinder temperature 290 ° C., mold temperature set at 80 ° C.) with an injection time of 20 A flat plate test piece of 50 × 90 × 3 mm was prepared at a cooling time of 20 seconds, and the test was performed.
A test piece of 10 × 4 × 3 mm was cut out from the central portion of the flat plate, and in accordance with JIS K7197, TMA-7 (manufactured by Perkin Elmer) was used, and the temperature increase rate was 5 ° C./min, and the load was 10 mN. The linear expansion coefficient of -30 to 80 ° C was measured.

<Surface appearance of molded product>
1. Dispersibility of filler (white foreign matter)
The resin composition pellets obtained in the examples and comparative examples were dried at 80 ° C. for 3 hours, and then injected with a Toshiba IS-80EPN molding machine (cylinder temperature 305 ° C., mold temperature 110 ° C.) with an injection time 20 A flat plate test piece of 150 × 150 × 3 mm was prepared at a cooling time of 20 seconds, and the presence or absence of white foreign matter on the flat plate surface was visually determined.
2. Surface smoothness
Using the same flat plate test piece as the one whose linear expansion coefficient was measured, the average value of the surface roughness (Ra) was evaluated. The smaller the value, the better the smoothness.
Based on JIS B 0601 (1994), the center line average roughness (Ra) of the flat plate surface portion was measured using a surface roughness meter Surfcom 579A (manufactured by Japan International Tokyo Seimitsu Co., Ltd.).
Measurement conditions Stylus: Standard probe (made of diamond, tip R5μm)
Movement speed of stylus: 0.5 mm / second
Measurement length: 50mm
The average value of 10 measurement points was calculated.

<Productivity>
Upper limit of discharge rate that can maintain good dispersibility of filler.
When the discharge amount is lowered and shearing is applied, the filler dispersion in the composition is improved. Therefore, the upper limit of the discharge amount at which a composition with good filler dispersion (no white foreign matter) can be obtained was used as an index of productivity. (Pellets were sampled every 50 kg / hr and confirmed by conducting the filler dispersibility evaluation described above.)
<Conductivity>
The resin composition pellets obtained in the examples and comparative examples were dried at 80 ° C. for 3 hours, and then a dumbbell bar using a Toshiba IS-80EPN molding machine (cylinder temperature set at 280 ° C. and mold temperature set at 80 ° C.). As described in ISO294. Both ends of the test piece were broken to obtain a test piece having a uniform cross-sectional area of 10 × 4 mm, a length of 70 mm, and fractured surfaces at both ends.
About how to fold a test piece, it carried out by the method of breaking after immersing the test piece which scratched with the cutter knife beforehand in dry ice / methanol of -75--70 degreeC for 1 hour. Silver paint was applied to the fracture surfaces at both ends, and the volume resistivity between both fracture surfaces was measured with an applied voltage of 250 V using an electrometer (manufactured by Advantest, Japan, R8340A). The measurement was performed using five different test pieces, and the addition average value was defined as conductivity (volume specific resistance value).
Hereinafter, detailed description will be given in Examples and Comparative Examples.

[Example 1]
The twin screw extruder [ZSK-58MC: Coperion Co., Ltd.] having an L / D of 46 having an upstream portion (first supply port), a middle flow portion (second supply port), and a downstream portion (third supply port) of the extruder (Germany)] under the conditions set at a cylinder temperature of 300 ° C., a screw rotation speed of 300 rpm, and a discharge rate of 400 kg / hr. Supply the improver, supply the polyamide and the wollastonite having a small aspect ratio from the second supply port, and further supply the wollastonite having the large aspect ratio from the third supply port to obtain pellets of the resin composition. Created.
The obtained pellets were molded by the method described above and subjected to various tests. The results are shown in Table 1.

[Example 2]
Compared to Example 1, except that the composition of wollastonite was changed, melt-kneading was performed under the same extruder and extrusion conditions as in Example 1 to prepare resin composition pellets.
Each obtained pellet was shape | molded by the above-mentioned method, the various test was done, and the result is shown in Table 1.

[Example 3]
Table 1 shows the results obtained by performing the same tests as in Example 1 except that wollastonite without surface treatment was used, and performing various tests.

[Example 4]
Except having changed polyamide, it implemented similarly to Example 1 and performed various tests, and the result is shown in Table 1.

[Comparative Example 1]
Table 1 shows the results of various tests performed in the same manner as in Example 1 except that wollastonite having a small aspect ratio and wollastonite having a large aspect ratio were supplied from the third supply port.
The composition of Comparative Example 1 is exactly the same as that of Example 1, but it can be seen that the properties of the resulting composition vary greatly depending on the production method.

[Example 5]
Table 1 shows the results of various tests conducted in the same manner as in Example 1, except that wollastonite having a small aspect ratio and wollastonite having a large aspect ratio were supplied from the second supply port.

[Example 6]
Table 1 shows the results of various tests conducted in the same manner as in Example 1, except that wollastonite having a large aspect ratio and a large average particle diameter was used.

[Example 7]
The composition shown in Table 1 was added with a conductive master batch, melt kneaded to produce pellets of the resin composition, and various tests were performed. The results are shown in Table 1.

  The thermoplastic resin composition of the present invention maintains excellent heat resistance, impact strength, and linear expansion coefficient, while improving surface smoothness and poor filler dispersion that causes poor coating adhesion (white surface of molded product) The foreign matter) has been greatly improved, and the productivity at the time of manufacture has been greatly improved. In particular, it can be suitably used as an outer plate material for automobiles.

Claims (13)

  A method for producing a resin composition comprising (A) polyamide, (B) polyphenylene ether, and (C) at least two types of wollastonite having different aspect ratios, wherein the wollastonite (C-1) has a small aspect ratio. Is supplied together with polyamide and melt-kneaded to produce a thermoplastic resin composition.   The thermoplastic resin composition according to claim 1, wherein the wollastonite (C-2) having a large aspect ratio is supplied and melt-kneaded after (A) polyamide and (B) polyphenylene ether are melt-kneaded. Manufacturing method.   The thermoplastic resin composition according to any one of claims 1 to 2, wherein the wollastonite (C-1) having a small aspect ratio has an aspect ratio of less than 8 and an average particle diameter of 2 to 9 µm. Manufacturing method.   The thermoplastic resin composition according to any one of claims 1 to 3, wherein the wollastonite (C-1) having a small aspect ratio has an aspect ratio of 6 or less and an average particle diameter of 2 to 7 µm. Manufacturing method.   The thermoplastic resin composition according to any one of claims 1 to 4, wherein the wollastonite (C-2) having a large aspect ratio has an aspect ratio of 8 or more and an average particle diameter of 2 to 11 µm. Manufacturing method.   The thermoplastic resin composition according to any one of claims 1 to 5, wherein the wollastonite (C-2) having a large aspect ratio has an aspect ratio of 10 or more and an average particle diameter of 3 to 10 µm. Manufacturing method.   (A) The polyamide is at least one selected from polyamide 6, polyamide 6,6, polyamide 6 / 6,6, polyamide 6,12 and polyamide 6,6 / 6, I. A method for producing the thermoplastic resin composition according to item 1.   Furthermore, (D) Conductive material is included, The manufacturing method of the thermoplastic resin composition of Claim 1 characterized by the above-mentioned.   The method for producing a thermoplastic resin composition according to claim 8, wherein the conductive material is at least one selected from the group consisting of conductive carbon black, carbon fibrils, and carbon nanotubes.   The method for producing a thermoplastic resin composition according to claim 8 or 9, wherein (D) the conductive material is added as a conductive masterbatch that is previously melt-kneaded with (A) polyamide.   The thermoplastic composition manufactured by the manufacturing method of the thermoplastic resin composition of any one of Claims 1-10.   The molded object formed by shape | molding the thermoplastic resin composition of Claim 11.   The exterior material for motor vehicles formed by shape | molding the thermoplastic resin composition of Claim 11.