Thermoplastic resin composition

Abstract

To provide a thermoplastic resin composition excellent in balance of impact resistance, heat resistance, weather resistance, dimensional stability and thermal stability.SOLUTION: There are provided: a thermoplastic resin composition which contains a polycarbonate resin, a graft copolymer, a copolymer containing an aromatic vinyl monomer and a vinyl cyanide monomer, and talc in specific amounts; and a thermoplastic resin composition which contains a polycarbonate resin, a graft copolymer, a copolymer containing an aromatic vinyl monomer and a vinyl cyanide monomer, talc, and a phosphoric acid compound in specific amounts.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a thermoplastic resin composition excellent in the balance of impact resistance, heat resistance, weather resistance, dimensional stability, and thermal stability.

Background Art

[0002] A composition composed of a polycarbonate resin and an ABS resin (hereinafter referred to as a PC / ABS resin) is used in various applications such as vehicle parts, household electrical appliances, and office equipment parts because it is excellent in impact resistance, heat resistance, and moldability. In particular, vehicle parts and the like tend to be larger in size and have more complex designs. In addition, in order to reduce the weight of the vehicle, the wall thickness of the molded product is designed to be thinner, so materials excellent in performance such as moldability, impact resistance, and heat resistance are required. In some cases, a PC / ABS resin is adopted as one of the options.

[0003] In the PC / ABS resin, when glass fibers, carbon fibers, etc. are blended to improve rigidity and dimensional stability, there is a problem that impact resistance decreases and the appearance of the molded product deteriorates. On the other hand, when talc is blended, although the appearance of the molded product is good, there is a problem that the thermal stability decreases and an appearance defect called silver appears on the surface of the molded product in the injection molding process.

[0004] And, as a method for improving the thermal stability when talc is blended, for example, Patent Document 1 discloses a resin composition containing a polycarbonate resin, a graft polymer, talc, and a phosphoric acid ester compound, and Patent Document 2 discloses a resin composition containing granular organic phosphoric acid ester compound-containing talc and a rubbery polymer in a resin having an aromatic polycarbonate resin as an essential component, and Patent Document 3 discloses a resin composition containing an aromatic polycarbonate resin, an emulsion-polymerized thermoplastic resin, and an acidic phosphoric acid ester having a defined structural formula.

[0005] However, in recent years, due to the trend of increasing size of molded parts, complexity of shape design, and thinning due to weight reduction, the molding temperature has also tended to increase, and further thermal stability is required, but it is still not satisfactory.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

[0007]

Patent Document 2

[0008]

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0009] An object of the present invention is to provide a thermoplastic resin composition excellent in the balance of impact resistance, heat resistance, weather resistance, dimensional stability, and thermal stability.

Means for Solving the Problems

[0010] That is, the present invention is composed of the following [1] to [5]. [1] A thermoplastic resin composition containing a polycarbonate resin (A), a graft copolymer (B), a copolymer (C), and talc (D), and satisfying the following conditions (1) to (7). (1) The content of the polycarbonate resin (A) is 40 to 80% by mass in 100% by mass in total of (A), (B), (C), and (D). (2) The graft copolymer (B) is a graft copolymer obtained by graft copolymerizing a rubbery polymer (b-1) and a monomer component (b-2) containing at least one selected from an aromatic vinyl monomer, a vinyl cyanide monomer, and a (meth)acrylate monomer. (3) The content of the graft copolymer (B) is 5 to 45% by mass in the total 100% by mass of (A), (B), (C) and (D). (4) The copolymer (C) is a copolymer formed by polymerizing a monomer component containing an aromatic vinyl monomer and a vinyl cyanide monomer. (5) The content of the copolymer (C) is 0 to 39% by mass in the total 100% by mass of (A), (B), (C) and (D). (6) The content of the talc (D) is 5 to 30% by mass in the total 100% by mass of (A), (B), (C) and (D). (7) The resin pH of the thermoplastic resin composition is 5.0 to 6.8. [2] The thermoplastic resin composition according to [1], characterized in that it contains 0.01 to 1.5 parts by mass of a phosphoric acid compound (E) with respect to 100 parts by mass in total of (A), (B), (C) and (D). [3] A thermoplastic resin composition containing a polycarbonate resin (A), a graft copolymer (B), a copolymer (C), a talc (D) and a phosphoric acid compound (E), and satisfying the following conditions (1) to (8). (1) The content of the polycarbonate resin (A) is 40 to 80% by mass in the total 100% by mass of (A), (B), (C) and (D). (2) The graft copolymer (B) is a graft copolymer formed by graft polymerization of a rubber polymer (b-1) and a monomer component (b-2) containing at least one selected from an aromatic vinyl monomer, a vinyl cyanide monomer and a (meth)acrylate monomer. (3) The content of the graft copolymer (B) is 5 to 45% by mass in the total 100% by mass of (A), (B), (C) and (D). (4) The copolymer (C) is a copolymer formed by polymerizing a monomer component containing an aromatic vinyl monomer and a vinyl cyanide monomer. (5) The content of the copolymer (C) is 0 to 39% by mass in the total 100% by mass of (A), (B), (C) and (D). (6) The content of the talc (D) is 5 to 30% by mass in the total 100% by mass of (A), (B), (C) and (D). (7) The content of the phosphate compound (E) is 0.01 to 1.5 parts by mass with respect to 100 parts by mass in total of (A), (B), (C) and (D). (8) The resin pH of the thermoplastic resin composition is 6.8 or less. [4] A thermoplastic resin composition comprising a polycarbonate resin (A), a graft copolymer (B), a copolymer (C), talc (D) and a phosphate compound (E), and satisfying the following conditions (1) to (8). (1) The content of the polycarbonate resin (A) is 40 to 80% by mass in 100% by mass in total of (A), (B), (C) and (D). (2) The graft copolymer (B) is a graft copolymer formed by graft-polymerizing a rubbery polymer (b-1) and a monomer component (b-2) containing at least one selected from an aromatic vinyl monomer, a vinyl cyanide monomer and a (meth)acrylate monomer. (3) The resin pH of the graft copolymer (B) is 3 to 6.6. (4) The content of the graft copolymer (B) is 5 to 45% by mass in 100% by mass in total of (A), (B), (C) and (D). (5) The copolymer (C) is a copolymer formed by polymerizing a monomer component containing an aromatic vinyl monomer and a vinyl cyanide monomer. (6) The content of the copolymer (C) is 0 to 39% by mass in 100% by mass in total of (A), (B), (C) and (D). (7) The content of the talc (D) is 5 to 30% by mass in 100% by mass in total of (A), (B), (C) and (D). (8) The content of the phosphate compound (E) is 0.01 to 1.5 parts by mass with respect to 100 parts by mass in total of (A), (B), (C) and (D). [5] The thermoplastic resin composition according to any one of [1] to [4], characterized by containing 3 to 13 parts by mass of a phosphate ester with respect to 100 parts by mass in total of (A), (B), (C) and (D). [Effect of the Invention]

[0011] The present invention can provide a thermoplastic resin composition excellent in the balance of impact resistance, heat resistance, weather resistance, dimensional stability, and thermal stability.

Embodiments for Carrying Out the Invention

[0012] Hereinafter, the present invention will be described in detail.

[0013] The thermoplastic resin composition according to the first aspect of the present invention is a thermoplastic resin composition containing a polycarbonate resin (A), a graft copolymer (B), a copolymer (C), and talc (D), and the resin pH of the thermoplastic resin composition is defined within a specific range.

[0014] The thermoplastic resin composition according to the second aspect of the present invention is a thermoplastic resin composition containing a polycarbonate resin (A), a graft copolymer (B), a copolymer (C), talc (D), and a phosphoric acid compound (E), and the resin pH of the thermoplastic resin composition is defined within a specific range.

[0015] The thermoplastic resin composition according to the third aspect of the present invention is a thermoplastic resin composition containing a polycarbonate resin (A), a graft copolymer (B), a copolymer (C), talc (D), and a phosphoric acid compound (E), and the resin pH of the graft copolymer (B) is defined within a specific range.

[0016] As the polycarbonate resin (A) used in the thermoplastic resin compositions according to the first, second, and third aspects of the present invention, it is a polymer obtained by a phosgene method in which various dihydroxydiaryl compounds are reacted with phosgene, or a transesterification method in which a dihydroxydiaryl compound is reacted with a carbonic acid ester such as diphenyl carbonate. Representative examples include 2,2-bis(4-hydroxyphenyl)propane, and a polycarbonate resin produced from “bisphenol A”.

[0017] Examples of the above dihydroxydiaryl compounds include, in addition to bisphenol A, bis(4-hydroxydiphenyl)methane, 1,1-bis(4-hydroxyphenyl)ethane, 2,2-bis(4-hydroxyphenyl)butane, 2,2-bis(4-hydroxyphenyl)octane, bis(4-hydroxyphenyl)diphenylmethane, 2,2-bis(4-hydroxy-3-methylphenyl)propane, 1,1-bis(4-hydroxy-3-tert-butylphenyl)propane, 2,2-bis(4-hydroxy-3-bromophenyl)propane, 2,2-bis(4-hydroxy-3,5-dibromophenyl)propane, 2,2-bis(4-hydroxy-3,5-dichlorophenyl)propane and other bis(hydroxyaryl)alkanes; 1,1-bis(4-hydroxyphenyl)cyclopentane, 1,1-bis(4-hydroxyphenyl)cyclohexane and other bis(hydroxyaryl)cycloalkanes; 4,4'-dihydroxydiphenyl ether, 4,4'-dihydroxy-3,3'-dimethyldiphenyl ether and other dihydroxydiaryl ethers; 4,4'-dihydroxydiphenyl sulfide, 4,4'-dihydroxy-3,3'-dimethyldiphenyl sulfide and other dihydroxydiaryl sulfides; 4,4'-dihydroxydiphenyl sulfoxide and other dihydroxydiaryl sulfoxides; 4,4'-dihydroxydiphenyl sulfone, 4,4'-dihydroxy-3,3'-dimethyldiphenyl sulfone and other dihydroxydiaryl sulfones.

[0018] These may be used alone or in admixture of two or more. In addition to these, piperazine, dipiperidyl hydroquinone, resorcin, 4,4'-dihydroxydiphenyls and the like may be mixed.

[0019] Furthermore, the above dihydroxydiaryl compound and a trivalent or higher phenolic compound as shown below may be mixed and used. Examples of the trivalent or higher phenol include phloroglucinol, 4,6-dimethyl-2,4,6-tri-(4-hydroxyphenyl)-heptene, 4,6-dimethyl-2,4,6-tri-(4-hydroxyphenyl)-heptane, 1,3,5-tri-(4-hydroxyphenyl)benzol, 1,1,1-tri-(4-hydroxyphenyl)ethane, 2,2-bis-[4,4-bis(4-hydroxyphenyl)cyclohexyl]propane, and the like. When producing these polycarbonate resins, the weight average molecular weight of the polycarbonate resin is usually 10,000 to 80,000, preferably 15,000 to 60,000. A molecular weight regulator, a catalyst, etc. can be used as necessary. The above weight average molecular weight can be measured by gel permeation chromatography (GPC) using polystyrene as a standard substance.

[0020] The graft copolymer (B) used in the thermoplastic resin composition according to the first, second, and third aspects of the present invention is obtained by graft-polymerizing a monomer component (b-2) containing at least one selected from an aromatic vinyl monomer, a vinyl cyanide monomer, and a (meth)acrylate monomer onto a rubbery polymer (b-1).

[0021] The rubbery polymer (b-1) constituting the graft copolymer (B) is not particularly limited, and conjugated diene rubbers such as polybutadiene rubber, styrene-butadiene rubber (SBR), acrylonitrile-butadiene rubber (NBR), etc., ethylene-propylene rubber, ethylene-propylene-non-conjugated diene (ethylidene norbornene, dicyclopentadiene, etc.) rubber, etc., acrylic rubbers such as polybutyl acrylate rubber, silicone rubbers, etc., which are obtained by known polymerization methods, can be used alone or in combination of two or more. The above acrylic rubbers include rubbers having a core-shell structure. Examples of the rubber having a core-shell structure (described as core / shell) include conjugated diene rubber / acrylic rubber, silicone rubber / acrylic rubber, hard polymer (glass transition temperature of 20 °C or higher) / acrylic rubber, etc. Examples of the hard polymer (glass transition temperature of 20 °C or higher) include polymers obtained by polymerizing monomers containing one or more monomers selected from aromatic vinyl monomers, vinyl cyanide monomers, and (meth)acrylate monomers. Among the above, polybutadiene rubber, styrene-butadiene rubber, ethylene-propylene-diene rubber, conjugated diene rubber / acrylic rubber, silicone rubber / acrylic rubber, hard polymer (glass transition temperature of 20 °C or higher) / acrylic rubber are preferred. The glass transition temperature of the hard polymer can be calculated by the FOX equation.

[0022] There is no particular limitation on the weight average particle diameter of the rubbery polymer (b-1), but from the viewpoint of impact resistance, 0.1 to 2.0 μm is preferred, and 0.15 to 1.0 μm is more preferred. Also, it can be adjusted by aggregating and enlarging a rubbery polymer having a weight average particle diameter of 0.05 to 0.3 μm.

[0023] The graft copolymer (B) is formed by graft-polymerizing a monomer component (b-2) containing at least one monomer selected from aromatic vinyl monomers, vinyl cyanide monomers, and (meth)acrylate monomers onto the above rubbery polymer (b-1).

[0024] Examples of the aromatic vinyl monomer as the monomer component (b-2) include styrene, α-methylstyrene, paramethylstyrene, bromostyrene, etc., and one or more of them can be used.

[0025] Examples of the vinyl cyanide monomer as the monomer component (b-2) include acrylonitrile, methacrylonitrile, ethacrylonitrile, fumaronitrile, etc., and one or more of them can be used.

[0026] Examples of the (meth)acrylic acid ester monomer as the monomer component (b-2) include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate, 2-ethylhexyl acrylate, phenyl (meth)acrylate, 4-t-butylphenyl (meth)acrylate, (di)bromophenyl (meth)acrylate, chlorophenyl (meth)acrylate, etc., and one or more of them can be used.

[0027] The monomer component (b-2) may contain other monomers copolymerizable with the aromatic vinyl monomer, vinyl cyanide monomer, and (meth)acrylic acid ester monomer, and examples include maleimide monomers, amide monomers, unsaturated carboxylic acid monomers, polyfunctional monomers, etc., and one or more of them can be used.

[0028] Examples of the maleimide monomer include N-phenylmaleimide, N-cyclohexylmaleimide, etc.

[0029] Examples of the amide monomer include acrylamide, methacrylamide, etc.

[0030] Examples of the unsaturated carboxylic acid monomer include (meth)acrylic acid, ethacrylic acid, maleic acid, fumaric acid, itaconic acid, crotonic acid, etc.

[0031] Examples of the polyfunctional monomer include divinylbenzene, allyl (meth) acrylate, ethylene glycol di (meth) acrylate, glycidyl (meth) acrylate, diallyl phthalate, dicyclopentadiene di (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol hexa (meth) acrylate, 1, 4 - butanediol di (meth) acrylate, 1, 6 - hexanediol di (meth) acrylate, triallyl cyanurate, triallyl isocyanurate, and the like.

[0032] There is no particular limitation on the composition ratio of the above monomers graft - polymerized onto the rubbery polymer (b - 1). However, a composition ratio of 50 to 90% by mass of an aromatic vinyl - based monomer, 10 to 50% by mass of a vinyl cyanide - based monomer, and 0 to 40% by mass of other copolymerizable monomers; a composition ratio of 0 to 50% by mass of an aromatic vinyl - based monomer, 50 to 100% by mass of a (meth) acrylate - based monomer, and 0 to 50% by mass of other copolymerizable vinyl - based monomers; or a composition ratio of 20 to 70% by mass of an aromatic vinyl - based monomer, 20 to 70% by mass of a (meth) acrylate - based monomer, 10 to 60% by mass of a vinyl cyanide - based monomer, and 0 to 50% by mass of other copolymerizable monomers is preferred (assuming the total amount of monomers graft - polymerized onto the rubbery polymer is 100% by mass).

[0033] From the viewpoint of the balance of physical properties such as impact resistance and fluidity, the content of the rubbery polymer (b - 1) in the graft copolymer (B) is preferably 20 to 80% by mass, and more preferably 40 to 70% by mass.

[0034] There is no particular limitation on the graft ratio and the reduced viscosity of the acetone - soluble component of the graft copolymer (B). However, from the viewpoint of the balance of physical properties such as impact resistance and fluidity, the graft ratio is preferably 20 to 150%, more preferably 30 to 100%, and particularly preferably 36 to 75%. The reduced viscosity of the acetone - soluble component is preferably 0.2 to 1.5 dl / g, and more preferably 0.3 to 1.0 dl / g.

[0035] The graft ratio and the reduced viscosity of the acetone-soluble component can be determined as follows.

[0036] Separation method Approximately 2 g of the graft copolymer (B) and 60 ml of acetone were placed in an Erlenmeyer flask and immersed for 24 hours. Then, using a centrifuge, it was centrifuged at 15,000 rpm for 30 minutes to separate into a soluble part and an insoluble part. The insoluble part is obtained by drying at room temperature for one day and night by vacuum drying. The soluble part is obtained by precipitating the acetone-soluble part in methanol and drying at room temperature for one day and night by vacuum drying. Graft ratio Graft ratio (%) = (X - Y) / Y × 100 X: Amount of acetone-insoluble matter (g) after vacuum drying Y: Amount of rubbery polymer (g) in the graft copolymer Reduced viscosity of acetone-soluble content (dl / g) The acetone-soluble component was dissolved in N,N-dimethylformamide to form a solution with a concentration of 0.4 g / 100 ml, and then the reduced viscosity was determined from the flow-down time measured at 30 °C using a Cannon-Fenske viscometer tube.

[0037] The graft copolymer (B) obtained as described above usually mainly contains a graft polymer (B1 component) in which a monomer component containing a monomer component (b-2) is grafted onto a rubbery polymer (b-1), and also contains a copolymer (referred to as B2 component) in which a monomer component containing a monomer component (b-2) not grafted onto the rubbery polymer (b-1) is copolymerized. Therefore, in the present invention, when the B2 component contained in the graft copolymer (B) satisfies the monomer component constituting the copolymer (C), it means that the copolymer (C) is contained.

[0038] There is no particular limitation on the polymerization method of the graft copolymer (B), and it can be produced, for example, by an emulsion polymerization method, a suspension polymerization method, a solution polymerization method, a bulk polymerization method, or a combination of these methods. Among them, the emulsion polymerization method is preferable.

[0039] When the graft copolymer (B) is produced by an emulsion polymerization method, the product is usually a latex. The obtained latex can be made into a powder by going through the steps of coagulation, washing, dehydration, and drying. As the coagulant used in the coagulation step, sulfuric acid, magnesium sulfate, calcium chloride, aluminum sulfate, etc. can be dissolved in water and one or more of them can be used. Also, a recovery and drying method using a spray dryer or the like can be used without using a coagulant.

[0040] The resin pH of the graft copolymer (B) In the first and second forms of the present invention, there is no particular limitation, and it is preferably 3 to 6.6, more preferably 4 to 6.3, and even more preferably 4.5 to 5.9. In the third form of the present invention, it needs to be 3 to 6.6, preferably 4 to 6.3, and more preferably 4.5 to 5.9. By adjusting to the above range, a product with excellent thermal stability tends to be obtained. The resin pH of the graft copolymer (B) is measured in the state of a solid such as powder (powder) or granule, and is measured by the method described in the examples. In addition, when a part or all of the graft copolymer (B) and the copolymer (C) are mixed in a latex state to obtain a solid, the pH of the solid obtained by mixing is taken as the resin pH of the graft copolymer (B).

[0041] As a method for adjusting the resin pH of the graft copolymer (B), for example, when obtained by an emulsion polymerization method, the resin pH of the obtained powder can be adjusted by adjusting the pH of the slurry (aqueous dispersion of coagulated particles) obtained in the coagulation step. For example, it can be obtained by adding an acidic aqueous solution such as sulfuric acid or hydrochloric acid in the coagulation step to lower the pH of the slurry.

[0042] The copolymer (C) used in the thermoplastic resin composition according to the first, second, and third forms of the present invention is obtained by polymerizing a monomer component containing an aromatic vinyl monomer and a vinyl cyanide monomer.

[0043] Examples of the aromatic vinyl monomer constituting the copolymer (C) include styrene, α-methylstyrene, paramethylstyrene, bromostyrene, etc., and one or more of them can be used.

[0044] Examples of the vinyl cyanide monomer constituting the copolymer (C) include acrylonitrile, methacrylonitrile, ethacrylonitrile, fumaronitrile, etc., and one or more of them can be used.

[0045] Furthermore, the copolymer (C) may contain other monomers copolymerizable with the aromatic vinyl monomer and the vinyl cyanide monomer, and examples include (meth)acrylate monomers, maleimide monomers, amide monomers, unsaturated carboxylic acid monomers, polyfunctional monomers, etc., and one or more of them can be used. As these monomers, those similar to the above-mentioned monomer component (b-2) can be used.

[0046] Although there is no particular limitation on the composition ratio of the monomers constituting the copolymer (C), examples of the composition ratio include 50 to 90% by mass of the aromatic vinyl monomer, 10 to 50% by mass of the vinyl cyanide monomer, and 0 to 40% by mass of other copolymerizable monomers; 20 to 70% by mass of the aromatic vinyl monomer, 10 to 60% by mass of the vinyl cyanide monomer, 20 to 70% by mass of the (meth)acrylate monomer, and 0 to 50% by mass of other copolymerizable monomers.

[0047] Although there is no particular limitation on the reduced viscosity of the copolymer (C), from the viewpoint of the balance of physical properties such as impact resistance and fluidity, it is preferably 0.2 to 1.5 dl / g, and more preferably 0.3 to 1.0 dl / g.

[0048] The above reduced viscosity can be determined by the following formula.

[0049] The copolymer (C) was dissolved in N,N-dimethylformamide to form a solution with a concentration of 0.4 g / 100 ml, and then the reduced viscosity was determined from the flow-down time measured at 30 °C using a Cannon-Fenske viscometer tube.

[0050] There is no particular limitation on the polymerization method of the copolymer (C) constituting the above thermoplastic resin composition, and it can be produced, for example, by an emulsion polymerization method, a suspension polymerization method, a solution polymerization method, a bulk polymerization method, or a combination of these methods.

[0051] The talc (D) used in the thermoplastic resin compositions according to the first, second, and third aspects of the present invention is magnesium hydrosilicate having a layered structure, and the average particle diameter by the laser diffraction particle size measurement method is preferably 0.1 to 50 μm, more preferably 0.5 to 25 μm, and even more preferably 1 to 15 μm.

[0052] The phosphoric acid compound (E) used in the thermoplastic resin compositions according to the second and third aspects of the present invention is a compound in which a hydroxyl group and an oxo group are bonded to a phosphorus atom, and examples thereof include phosphoric acid, phosphorous acid, hypophosphorous acid, diphosphoric acid (polyphosphoric acid), methyl phosphate, dimethyl phosphate, and the like.

[0053] The content of the polycarbonate resin (A) constituting the thermoplastic resin compositions according to the first, second, and third aspects of the present invention needs to be 40 to 80% by mass in 100% by mass in total of (A), (B), (C), and (D), preferably 42 to 77% by mass, and more preferably 45 to 75% by mass. By adjusting to the above range, the balance of fluidity, impact resistance, and heat resistance can be improved.

[0054] The content of the graft copolymer (B) constituting the thermoplastic resin compositions according to the first, second, and third aspects of the present invention needs to be 5 to 45% by mass in 100% by mass in total of (A), (B), (C), and (D), preferably 7 to 35% by mass, and more preferably 10 to 28% by mass. By adjusting to the above range, the impact resistance can be improved.

[0055] The content of the copolymer (C) constituting the thermoplastic resin composition according to the first, second, and third aspects of the present invention needs to be 0 to 39% by mass in the total 100% by mass of (A), (B), (C), and (D), preferably 2 to 36% by mass, and more preferably 4 to 33% by mass. By adjusting to the above range, the fluidity (moldability) can be improved. Further, when the B2 component contained in the graft copolymer (B) satisfies the monomer components constituting the copolymer (C), the content of the copolymer (C) is the sum of the B2 component calculated from the graft ratio of the graft copolymer (B).

[0056] The content of talc (D) constituting the thermoplastic resin composition according to the second and third aspects of the present invention needs to be 5 to 30% by mass with respect to the total 100% by mass of (A), (B), (C), and (D), preferably 8 to 27% by mass, and more preferably 12 to 22% by mass. By adjusting to the above range, the dimensional stability and weather resistance can be improved.

[0057] The content of the phosphoric acid compound (E) constituting the thermoplastic resin composition according to the second and third aspects of the present invention needs to be 0.01 to 1.5 parts by mass with respect to the total 100 parts by mass of (A), (B), (C), and (D), preferably 0.03 to 1.0 parts by mass, and more preferably 0.05 to 0.7 parts by mass. By adjusting to the above range, the thermal stability can be improved. Further, also in the first aspect of the present invention, the phosphoric acid compound (E) can be optionally added, and it is preferably 0.01 to 1.5 parts by mass, more preferably 0.03 to 1.0 parts by mass, and even more preferably 0.05 to 0.7 parts by mass with respect to the total 100 parts by mass of (A), (B), (C), and (D).

[0058] In the thermoplastic resin compositions according to the first, second, and third aspects of the present invention, other thermoplastic resins can be blended as long as the effects of the present invention are not impaired. Examples of such other thermoplastic resins include acrylic resins such as polymethyl methacrylate; polyolefin resins such as polyethylene and polypropylene; polyester resins such as polybutylene terephthalate resin, polyethylene terephthalate resin, and polylactic acid resin; polyamide resins; polyimide resins, and the like can be used.

[0059] Furthermore, in the thermoplastic resin compositions according to the first, second, and third aspects of the present invention, within a range not impairing the effects of the present invention, hindered amine-based light stabilizers; antioxidants such as hindered phenol-based, sulfur-containing organic compound-based, and phosphorus-containing organic compound-based; heat stabilizers such as phenol-based and acrylate-based; ultraviolet absorbers such as benzoate-based, benzotriazole-based, benzophenone-based, and salicylate-based; lubricants such as organic nickel-based and higher fatty acid amides; flame retardants and flame retardant aids such as polybromophenyl ether, tetrabromobisphenol-A, brominated epoxy oligomer, halogen-containing compounds such as brominated, phosphate esters, and antimony trioxide; odor masking agents; pigments such as carbon black and titanium oxide; dyes, etc. can also be added. Furthermore, reinforcing agents and fillers such as calcium carbonate, aluminum hydroxide, glass fiber, glass flake, glass bead, glass wool, carbon fiber, and metal fiber can also be added.

[0060] Among them, it is preferable to contain 3 to 13 parts by mass of phosphate ester with respect to a total of 100 parts by mass of (A), (B), (C) and (D) from the viewpoint of improving fluidity, and more preferably 4 to 10 parts by mass. Specific examples of the phosphate ester include trimethyl phosphate, triethyl phosphate, tributyl phosphate, tri(2-ethylhexyl) phosphate, tributoxyethyl phosphate, triphenyl phosphate, tricresyl phosphate, trixylenyl phosphate, tris(isopropylphenyl) phosphate, tris(phenylphenyl) phosphate, trinaphthyl phosphate, cresyldiphenyl phosphate, xylenyl diphenyl phosphate, diphenyl(2-ethylhexyl) phosphate, di(isopropylphenyl)phenyl phosphate, monoisodecyl phosphate, 2-acryloyloxyethyl acid phosphate, 2-methacryloyloxyethyl acid phosphate, diphenyl-2-acryloyloxyethyl phosphate, diphenyl-2-methacryloyloxyethyl phosphate, melamine phosphate, dimelamine phosphate, melamine pyrophosphate, triphenylphosphine oxide, tricresylphosphine oxide, diphenyl methane phosphonate, diethyl phenylphosphonate, resorcinol polyphenyl phosphate, resorcinol poly(di-2,6-xylyl) phosphate, bisphenol A polycresyl phosphate, hydroquinone poly(2,6-xylyl) phosphate and condensed phosphate esters such as condensates thereof. Examples of the condensed phosphate ester include resorcinol bis(di-2,6-xylyl) phosphate, resorcinol bis(diphenyl phosphate), bisphenol A bis(diphenyl phosphate). Commercially available products of resorcinol bis(di-2,6-xylyl) phosphate include PX-200 (manufactured by Daihachi Chemical Industry Co., Ltd.). Commercially available products of resorcinol bis(diphenyl phosphate) include CR-733S (manufactured by Daihachi Chemical Industry Co., Ltd.). Commercially available products of bisphenol A bis(diphenyl phosphate) include CR-741 (manufactured by Daihachi Chemical Industry Co., Ltd.).Among them, resorcinol bis(di-2,6-xylyl) phosphate and bisphenol A bis(diphenyl phosphate) are preferably used because of their excellent hydrolysis resistance, heat resistance, and low volatility.

[0061] The thermoplastic resin compositions according to the first, second, and third aspects of the present invention can be obtained by melt-kneading the above-described components. For melt-kneading, known kneaders such as rolls, Banbury mixers, single-screw extruders, multi-screw extruders, and kneaders can be used.

[0062] The resin pH of the obtained thermoplastic resin composition is In the first aspect of the present invention, it needs to be 5.0 to 6.8, and preferably 5.4 to 6.7. In the second aspect of the present invention, it needs to be 6.8 or less. In the third aspect of the present invention, there is no particular limitation, but it is preferably 5.0 to 6.8, and more preferably 5.4 to 6.7. By adjusting to the above range, those excellent in thermal stability tend to be obtained. The resin pH of the thermoplastic resin composition is measured in the state of granular solids such as pellets and is measured by the method described in the examples.

[0063] Examples of the method for adjusting the resin pH of the thermoplastic resin composition include a method of adjusting the resin pH of the graft copolymer (B) or copolymer (C) constituting the composition, and it can be adjusted by the same method as the method for adjusting the resin pH of the graft copolymer (B). Further, it can be adjusted by adding an acidic additive such as diphosphoric acid to the thermoplastic resin composition.

[0064] The thermoplastic resin composition thus obtained can be molded by injection molding, extrusion molding, compression molding, injection compression molding, blow molding, etc. to obtain a molded product.

Examples

[0065] The present invention will be specifically described below using examples, but the present invention is not limited thereto. In addition, the parts and % shown in the examples are based on weight. Moreover, the measurement of various physical properties in each example and comparative example was carried out by the following methods.

[0066] Charpy impact strength (NC) Using the pellets obtained in each example and comparative example, various test pieces were molded in accordance with ISO test method 294, and in accordance with ISO test method 179, with a thickness of 4 mm, the notched Charpy impact value was measured. Unit: kJ / m 2

[0067] Heat deflection temperature (HDT) Using the pellets obtained in each example and comparative example, various test pieces were molded in accordance with ISO test method 294, and in accordance with ISO 75, the deflection temperature under load of 1.8 MPa was measured. Unit: °C

[0068] Thermal stability Using an injection molding machine (J-180ADS, manufactured by Nippon Steel Works, Ltd., molding temperature 290 °C, mold temperature 60 °C), under the following conditions, a flat test piece (length × width × thickness = 400 mm × 100 mm × 3 mm) was molded. For weighing, when the material weighing of the molded product was 100%, about 140% was weighed and molded. Next, after weighing about 140% in such a way as to include about 40% of the resin remaining in the cylinder, it was retained for 270 seconds and molded at an injection speed of 30 mm / s. Whether there was any defect in the appearance of the obtained molded product was visually determined. The appearance defect was evaluated as follows. 〇: No dot-like silver on the surface of the molded product △: There are less than 1 to 10 dot-like silvers on the surface of the molded product ×: There are 10 or more dot-like silvers on the surface of the molded product

[0069] Dimensional stability The linear expansion coefficient was measured as an evaluation of dimensional stability. Dumbbells of type A1 in JIS K7139 were molded in accordance with ISO test method 294. Samples were cut out from the central part of the dumbbells, and the linear expansion coefficient in the MD direction (resin flow direction) was measured in accordance with JIS K7197. As the thermal analyzer, TMA-7100 manufactured by Hitachi High-Tech Science Corporation was used. The lower the numerical value, the better the dimensional stability, and the evaluation was carried out as follows. 〇: Linear expansion coefficient is less than 5×10 -5 / °C △: Linear expansion coefficient is 5×10 -5 / °C or more and 7×10 -5 / °C or less ×: Linear expansion coefficient exceeds 7×10 -5 / °C

[0070] Weather resistance For the weather resistance test, pellets obtained in each example and comparative example were used, and molded products (length × width × thickness = 90 mm × 55 mm × 2.5 mm) molded with an injection molding machine (SAV-30-30 cylinder temperature 250°C, mold temperature 60°C) were used. Using a Sunshine Weather Meter S80HBB manufactured by Suga Test Instruments Co., Ltd., an accelerated exposure test was conducted for 500 hours under the conditions of BPT of 63°C and with rain. Then, the color difference (ΔE) in the SCE method before and after exposure on the surface of the molded product was measured. The color difference was evaluated as follows using a spectrocolorimeter (CMS-35SP JC2 type manufactured by Murakami Color Technology Laboratory Co., Ltd.). 〇: ΔE is less than 7 △: ΔE is 7 or more and 15 or less ×: ΔE exceeds 15

[0071] Resin pH The resin pH of the graft copolymer (B) and the thermoplastic resin composition was measured as follows. (1) 1 g of the graft copolymer (B) or the thermoplastic resin composition and 40 ml of primary tetrahydrofuran (containing a stabilizer) were added to a 100 ml Erlenmeyer flask and allowed to stand for 24 hours. (2) Add 40 ml of primary methanol to a 200 ml beaker and stir with a magnetic stirrer. Add the sample obtained in (1) thereto, and further add 40 ml of pure water and stir. (3) The pH of the sample obtained in (2) was measured in accordance with JIS Z-8802. For the pH measurement, a desktop electric conductivity meter (CM-25R manufactured by Toa DKK Co., Ltd.) was used.

[0072] Polycarbonate resin (A) A polycarbonate resin having a viscosity average molecular weight of 20,500, composed of phosgene and bisphenol A.

[0073] Production of graft copolymer (B-1) Into a glass reactor, 60 parts by mass of an agglomerated and enlarged styrene-butadiene rubber (b-1) latex (styrene 5% by mass, butadiene 95% by mass, mass average particle diameter 440 nm) in terms of solid content was charged, stirring was started, and nitrogen substitution was performed. After nitrogen substitution, when the temperature inside the tank was raised to reach 65 °C, an aqueous solution prepared by dissolving 0.06 part by mass of glucose, 0.03 part by mass of sodium pyrophosphate anhydrous, and 0.001 part by mass of ferrous sulfate in 10 parts by mass of deionized water was added, and then the temperature was raised to 70 °C. Thereafter, a mixed solution of 10 parts by mass of acrylonitrile, 30 parts by mass of styrene, 0.3 part of tertiary dodecyl mercaptan, 0.1 part by mass of t-butyl hydroperoxide and an emulsifier aqueous solution prepared by dissolving 1.0 part by mass (in terms of solid content) of potassium oleate in 20 parts by mass of deionized water was continuously dropped over 4 hours. After dropping, it was held for 3 hours to obtain a graft copolymer (B-1) latex. Thereafter, deionized water was charged so that the final slurry concentration became 23% with respect to 100 parts by mass (solid content) of the obtained graft copolymer (B-1) latex, 4.5 parts by mass of magnesium sulfate, and 0.8 part by mass of 10% sulfuric acid were added, and it was heated to 93 °C. Thereafter, the graft copolymer (B-1) latex was added and coagulated to obtain a slurry containing a polymer. Thereafter, the obtained slurry was dehydrated and dried to obtain a powder of the graft copolymer (B-1). The graft ratio of the obtained graft copolymer (B-1) was 42%, the reduced viscosity of the acetone-soluble part was 0.28 dl / g, and the resin pH was 5.4. Also, the mass average particle diameter of the above-mentioned aggregated and enlarged styrene-butadiene rubber latex was determined as follows. It was stained with osmium tetroxide (OsO4), photographed with a transmission electron microscope after drying. The areas of 800 rubber particles were measured using an image analysis processing apparatus (apparatus name: IP-1000PC manufactured by Asahi Kasei Corporation), the equivalent circle diameter (diameter) was determined, and the mass average particle diameter was calculated.

[0074] Production of graft copolymer (B-2) To 100 parts by mass (solid content) of the obtained graft copolymer (B-1) latex, deionized water was charged so that the final slurry concentration became 23%, 4.5 parts by mass of magnesium sulfate was added, and it was heated to 93°C. Then, the graft copolymer (B-1) latex was added and coagulated to obtain a slurry containing the polymer. Then, the obtained slurry was dehydrated and dried to obtain a powder of the graft copolymer (B-2). The graft ratio of the obtained graft copolymer (B-2) was 42%, the reduced viscosity of the acetone-soluble part was 0.28 dl / g, and the resin pH was 8.4.

[0075] Production of copolymer (C) A copolymer (C) composed of 75 parts by mass of styrene and 25 parts by mass of acrylonitrile was obtained by a known bulk polymerization method. By the above method, the reduced viscosity of the obtained copolymer (C) was 0.50 dl / g.

[0076] Talc (D) Manufactured by Hayashi Kasei Co., Ltd., Talc: UPN-HST 0.5

[0077] Phosphoric acid compound (E) Manufactured by Fujifilm Wako Pure Chemical Corporation, Diphosphoric acid

[0078] Other additives Manufactured by Daihachi Chemical Industry Co., Ltd., Aromatic condensed phosphate ester: PX-200

[0079] Examples 1 to 7 and Comparative Examples 1 to 5 A polycarbonate resin (A), a graft copolymer (B), a copolymer (C), talc (D), a phosphate compound (E), and other additives were mixed at the compounding ratios shown in Table 1, and then melt-kneaded and pelletized using a 26-mm diameter twin-screw extruder with a cylinder temperature set at 260°C under the conditions of a main screw rotation speed of 450 rpm and a discharge rate of 30 kg / hr. Also, various test pieces for evaluation were molded using an injection molding machine with these pellets.

[0080]

Table 1

[0081] As is clear from Table 1, in Examples 1 to 7 using the thermoplastic resin composition of the present invention, those excellent in the balance of impact resistance, heat resistance, weather resistance, dimensional stability, and thermal stability were obtained.

[0082] Regarding the thermoplastic resin composition according to the first aspect of the present invention, In Comparative Examples 1 to 3, the resin pH of the thermoplastic resin composition was outside the specified range, and they were inferior in thermal stability. In Comparative Example 4, since talc (D) was not added, it was inferior in dimensional stability and weather resistance. In Comparative Example 5, since the addition amount of talc (D) exceeded the specified range, it was inferior in impact resistance.

[0083] Regarding the thermoplastic resin composition according to the second aspect of the present invention, In Comparative Examples 1 to 2, the resin pH of the thermoplastic resin composition was outside the specified range, and they were inferior in thermal stability. In Comparative Example 3, since the addition amount of the phosphate compound (E) exceeded the specified range, it was inferior in thermal stability. In Comparative Example 4, since talc (D) was not added, it was inferior in dimensional stability and weather resistance. In Comparative Example 5, since the addition amount of talc (D) exceeded the specified range, it was inferior in impact resistance.

[0084] Regarding the thermoplastic resin composition according to the third aspect of the present invention, In Comparative Example 1, the resin pH of the graft copolymer (B) was outside the specified range, and it was inferior in thermal stability. In Comparative Example 2, since the phosphoric acid compound (E) was not added, it was inferior in thermal stability. In Comparative Example 3, since the addition amount of the phosphoric acid compound (E) exceeded the specified range, it was inferior in thermal stability. In Comparative Example 4, since talc (D) was not added, it was inferior in dimensional stability and weather resistance. In Comparative Example 5, since the addition amount of talc (D) exceeded the specified range, it was inferior in impact resistance.

Industrial Applicability

[0085] As described above, since the thermoplastic resin composition of the present invention is a thermoplastic resin composition excellent in the balance of impact resistance, heat resistance, weather resistance, dimensional stability and thermal stability, it can be suitably used as a material for large-sized molded parts used outdoors, such as parts for vehicle exterior, etc.

Claims

1. A thermoplastic resin composition containing a polycarbonate resin (A), a graft copolymer (B), a copolymer (C), and talc (D), and satisfying the following conditions (1) to (7). (1) The content of the polycarbonate resin (A) is 40 to 80% by mass in the total 100% by mass of (A), (B), (C), and (D). (2) The graft copolymer (B) is a graft copolymer formed by graft polymerization of a rubbery polymer (b-1) and a monomer component (b-2) containing at least one selected from an aromatic vinyl monomer, a vinyl cyanide monomer, and a (meth)acrylate monomer. (3) The content of the graft copolymer (B) is 5 to 45% by mass in the total 100% by mass of (A), (B), (C), and (D). (4) The copolymer (C) is a copolymer formed by polymerizing a monomer component containing an aromatic vinyl monomer and a vinyl cyanide monomer. (5) The content of the copolymer (C) is 0 to 39% by mass in the total 100% by mass of (A), (B), (C), and (D). (6) The content of the talc (D) is 5 to 30% by mass in the total 100% by mass of (A), (B), (C), and (D). (7) The resin pH of the thermoplastic resin composition is 5.0 to 6.

8.

2. The thermoplastic resin composition according to claim 1, characterized in that it contains 0.01 to 1.5 parts by mass of a phosphoric acid compound (E) with respect to 100 parts by mass of the total of (A), (B), (C), and (D).

3. A thermoplastic resin composition containing a polycarbonate resin (A), a graft copolymer (B), a copolymer (C), talc (D), and a phosphoric acid compound (E), and satisfying the following conditions (1) to (8). (1) The content of the polycarbonate resin (A) is 40 to 80% by mass in the total 100% by mass of (A), (B), (C), and (D). (2) The graft copolymer (B) is a graft copolymer formed by graft polymerization of a rubbery polymer (b-1) and a monomer component (b-2) containing at least one selected from an aromatic vinyl monomer, a vinyl cyanide monomer, and a (meth)acrylate monomer. (3) The content of the graft copolymer (B) is 5 to 45% by mass in the total 100% by mass of (A), (B), (C), and (D). (4) The copolymer (C) is a copolymer formed by polymerizing a monomer component containing an aromatic vinyl monomer and a vinyl cyanide monomer. (5) The content of the copolymer (C) is 0 to 39% by mass in the total 100% by mass of (A), (B), (C), and (D). (6) The content of talc (D) is 5 to 30% by mass in 100% by mass in total of (A), (B), (C) and (D). (7) The content of the phosphate compound (E) is 0.01 to 1.5 parts by mass with respect to 100 parts by mass in total of (A), (B), (C) and (D). (8) The resin pH of the thermoplastic resin composition is 6.8 or less.

4. (4) A thermoplastic resin composition comprising a polycarbonate resin (A), a graft copolymer (B), a copolymer (C), talc (D) and a phosphate compound (E), and satisfying the following conditions (1) to (8). (1) The content of the polycarbonate resin (A) is 40 to 80% by mass in 100% by mass in total of (A), (B), (C) and (D). (2) The graft copolymer (B) is a graft copolymer obtained by graft-polymerizing a rubbery polymer (b-1) and a monomer component (b-2) containing at least one selected from an aromatic vinyl monomer, a vinyl cyanide monomer and a (meth)acrylate monomer. (3) The resin pH of the graft copolymer (B) is 3 to 6.

6. (4) The content of the graft copolymer (B) is 5 to 45% by mass in 100% by mass in total of (A), (B), (C) and (D). (5) The copolymer (C) is a copolymer obtained by polymerizing a monomer component containing an aromatic vinyl monomer and a vinyl cyanide monomer. (6) The content of the copolymer (C) is 0 to 39% by mass in 100% by mass in total of (A), (B), (C) and (D). (7) The content of talc (D) is 5 to 30% by mass in 100% by mass in total of (A), (B), (C) and (D). (8) The content of the phosphate compound (E) is 0.01 to 1.5 parts by mass with respect to 100 parts by mass in total of (A), (B), (C) and (D).

5. (5) The thermoplastic resin composition according to any one of claims 1 to 4, comprising 3 to 13 parts by mass of a phosphate ester with respect to 100 parts by mass in total of (A), (B), (C) and (D).

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