JP2013224386A - Thermoplastic resin composition and molded product - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a crosslinked fine particle-containing thermoplastic resin composition improving dispersibility of crosslinked fine particles in a thermoplastic resin and achieving excellent surface appearance of an obtained molded product, and a molded product with excellent surface appearance.SOLUTION: A thermoplastic resin composition includes: crosslinked fine particles (A); an alkyl (meth)acrylate polymer (B); and a thermoplastic resin (C). A molded product obtained by molding the thermoplastic resin composition is also provided.

Description

  The present invention relates to a thermoplastic resin composition containing crosslinked fine particles having an excellent molded appearance and a molded product thereof.

  Crosslinked fine particles are used in various fields such as paint additives, matting agents for thermoplastic resins, and antiblocking agents. In particular, the use as a matting agent has attracted attention in recent years because it can give a unique texture that cannot be achieved by conventional matting technology that removes matting by embossing a mold.

  Many techniques have been proposed for using crosslinked fine particles as a matting agent. For example, Patent Document 1 discloses a proposal for acrylic crosslinked fine particles suitable for polyolefin resins.

  On the other hand, when additives such as matting agents, various fillers, and flame retardants are blended into the thermoplastic resin, their dispersibility may be a problem. In particular, when a polar additive is blended with a nonpolar polymer such as a polyolefin resin, sufficient dispersibility cannot be obtained, causing not only a poor appearance of a molded product, but also a problem that the performance of the blended additive is not sufficiently developed. May occur. As a method for solving such a problem, Patent Document 2 proposes a technique in which an alkyl (meth) acrylate having a predetermined molecular weight and having 2 or more carbon atoms efficiently disperses an additive such as a flame retardant or a foaming agent. Has been.

JP 2009-179667 A International Publication No. 2011/096596

  However, the method proposed in the above-mentioned Patent Document 1 is a method in which a part of the crosslinked fine particles agglomerates when the thermoplastic resin and the crosslinked fine particles are melt-kneaded, and the unevenness is considerably larger than the unevenness of the surface of the molded article usually obtained. Has occurred locally, resulting in poor appearance. Moreover, although the method of patent document 2 describes the method of improving the dispersibility of inorganic type fillers, there is no description regarding the dispersibility of organic type | system | group crosslinked fine particles, and the high degree to the thermoplastic resin of crosslinked fine particles is mentioned. The technology to achieve decentralization has been eagerly desired.

  An object of the present invention is to provide a crosslinked fine particle-containing thermoplastic resin composition that enhances the dispersibility of crosslinked fine particles in a thermoplastic resin and is excellent in the surface appearance of the resulting molded article.

The present invention relates to a thermoplastic resin composition containing crosslinked fine particles (A), an alkyl (meth) acrylate polymer (B) and a thermoplastic resin (C).
Moreover, this invention relates to the molded object obtained by shape | molding the said thermoplastic resin composition.

  ADVANTAGE OF THE INVENTION According to this invention, the dispersibility of the crosslinked fine particle in a thermoplastic resin can be improved, and the crosslinked fine particle containing thermoplastic resin composition excellent in the surface external appearance of the molded object obtained can be provided.

  The thermoplastic resin composition of the present invention contains crosslinked fine particles (A). The kind of the crosslinked fine particles (A) is not particularly limited, and acrylic crosslinked fine particles, styrene crosslinked fine particles, silicone crosslinked fine particles, diene crosslinked fine particles and the like can be used.

  The crosslinked fine particles (A) are fine particles obtained by polymerizing a crosslinkable monomer and various monofunctional monomers. The polymerization method is not particularly limited, and known aqueous polymerization methods such as emulsion polymerization, soap-free polymerization, fine suspension polymerization, and suspension polymerization can be used.

  The crosslinkable monomer used when polymerizing the crosslinked fine particles (A) is a polyfunctional monomer having two or more polymerizable double bonds, such as ethylene glycol dimethacrylate, propylene glycol dimethacrylate. 1, 4-butylene glycol dimethacrylate, alkylene glycol dimethacrylate such as 1,3-butylene glycol dimethacrylate; allyl methacrylate; polyvinylbenzene such as divinylbenzene and trivinylbenzene; butadiene and the like. These polyfunctional monomers can be used alone or in combination of two or more.

  Monofunctional monomers used for polymerizing the crosslinked fine particles (A) include (meth) acrylic acid, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, and n-butyl (meth). Acrylate, i-butyl (meth) acrylate, sec-butyl (meth) acrylate, t-butyl (meth) acrylate, n-hexyl (meth) acrylate, cyclohexyl (meth) acrylate, n-octyl (meth) acrylate, 2- Acrylic monomers such as ethylhexyl (meth) acrylate, stearyl (meth) acrylate, lauryl (meth) acrylate, isobornyl (meth) acrylate, benzyl (meth) acrylate, phenyl (meth) acrylate; aroma such as styrene and α-methylstyrene Family vinyl Body; halogen-containing monomers such as vinyl chloride, vinyl bromide, vinylidene chloride, vinylidene bromide, vinylidene fluoride, tetrafluoroethylene; vinyl ethers such as methyl vinyl ether and butyl vinyl ether; unsaturated nitriles such as (meth) acrylonitrile Examples include a polymer. These monomers can be used alone or in combination of two or more.

  The content of the crosslinkable monomer in the crosslinked fine particles (A) is not particularly defined, but is preferably 0.5 to 40 parts by mass when the total amount of monomers used is 100 parts by mass. If content of a crosslinkable monomer is 0.5 mass part or more, it will become a crosslinked particle of sufficient crosslinking degree. If content of a crosslinkable monomer is 40 mass parts or less, the polymerization efficiency of a crosslinkable monomer will be favorable.

  The average particle size of the crosslinked fine particles (A) is not particularly limited, and can be set to any particle size depending on the purpose. When the crosslinked fine particles are used as a matting agent, it is preferably set in the range of 1 to 100 μm.

  As the crosslinked fine particles (A), for example, “Metabrene F-410”, “Same F-430”, “Same F-444” (trade name, manufactured by Mitsubishi Rayon Co., Ltd.), “Techpolymer MBX-5”, “MBX-8”, “MBX-12”, “MBX-20”, “MBX-30”, “MBX-40”, “BM30X-5”, “BM30X-8”, “ "SBX-6", "SBX-8", "Same MBP-8", "Same ARX-15", "Same PAC-M810", "Same SSX-101", "Same ABX-8", "Same AF10X" -8 "," AFX-15 "," MSX "," SMX "(trade name, manufactured by Sekisui Plastics Co., Ltd.). The crosslinked fine particles can be used alone or in combination of two or more.

  The thermoplastic resin composition of the present invention contains an alkyl (meth) acrylate polymer (B). The alkyl (meth) acrylate polymer (B) is a polymer containing 50% by mass or more of an alkyl methacrylate unit having an alkyl group, and improves the dispersibility of the crosslinked fine particles (A) in the thermoplastic resin composition. The alkyl (meth) acrylate polymer (B) in the present invention is not a crosslinked structure but is defined as a polymer different from the crosslinked fine particles (A).

  Examples of alkyl (meth) acrylate monomers include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, n-butyl (meth) acrylate, i-butyl (meth) acrylate, sec-butyl ( (Meth) acrylate, t-butyl (meth) acrylate, n-hexyl (meth) acrylate, cyclohexyl (meth) acrylate, n-octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, stearyl (meth) acrylate, lauryl ( Examples include meth) acrylate, isobornyl (meth) acrylate, benzyl (meth) acrylate, and phenyl (meth) acrylate. Among these monomers, alkyl (meth) acrylates having 2 or more carbon atoms are preferable, alkyl (meth) acrylates having 4 carbon atoms are more preferable, and i-butyl methacrylate is preferable from the viewpoint of improving the dispersibility of the crosslinked fine particles (A). Is most preferred. These monomers may be used alone or in combination of two or more.

  As the alkyl (meth) acrylate polymer (B), a copolymerizable monomer component can be used in addition to the alkyl (meth) acrylate monomer. Examples of monomers other than alkyl (meth) acrylate monomers include aromatic vinyl monomers such as styrene, α-methylstyrene, and chlorostyrene; (meth) acrylic acid; vinyl cyanide such as (meth) acrylonitrile Monomers; vinyl ether monomers such as vinyl methyl ether and vinyl ethyl ether; vinyl carboxylate monomers such as vinyl acetate and vinyl tangle; olefins such as ethylene, propylene and butylene. These other monomers may be used individually by 1 type, and may use 2 or more types together.

  In the present specification, “(meth) acrylate” means “acrylate” or “methacrylate”.

  Examples of the polymerization method of the alkyl (meth) acrylate polymer (B) include known polymerization methods such as emulsion polymerization, soap-free emulsion polymerization, fine suspension polymerization, suspension polymerization, bulk polymerization, and solution polymerization.

  The particle structure in the case of polymerizing the alkyl (meth) acrylate polymer (B) using a polymerization method capable of obtaining a particle structure such as emulsion polymerization or soap-free emulsion polymerization may be a single layer structure or a multilayer structure. It may be a structure. When the particle structure is a multilayer structure particle, it is preferable that the particle structure is a three-layer structure or less from the viewpoint of economy.

  A known emulsifier can be used as an emulsifier when the alkyl (meth) acrylate polymer (B) is obtained by emulsion polymerization. For example, an anionic emulsifier, a nonionic emulsifier, a polymer emulsifier, radical polymerization is possible in the molecule. And reactive emulsifiers having an unsaturated double bond.

  Examples of the anionic emulsifier include “New Coal 560 SF”, “New Coal 562 SF”, “New Coal 707 SF”, “New Coal 707 SN”, “New Coal 714 SF”, “New Coal 723 SF”, “New Coal 740 SF”, “New Call 2308SF”, “New Call 2320SN”, “New Call 1305SN”, “New Call 271A”, “New Call 271NH”, “New Call 210”, “New Call 220”, “New Call RA331”, “New Call "Cole RA332" (trade name, manufactured by Nippon Emulsifier Co., Ltd.); "Latemul B-118E", "Lebenol WZ", "Neoperex G15" (trade name, manufactured by Kao Corporation); "Hitenol N08" (product) Name, Daiichi Kogyo Seiyaku Co., Ltd.) That.

  Examples of the nonionic emulsifier include “Nonipol 200” and “New Pole PE-68” (trade names, manufactured by Sanyo Chemical Industries, Ltd.).

  Examples of the polymer emulsifier include polyvinyl alcohol, polyhydroxyethyl (meth) acrylate, polyhydroxypropyl (meth) acrylate, and polyvinylpyrrolidone.

Examples of reactive emulsifiers include “Antox MS-60” and “Antox MS-2N” (trade name, manufactured by Nippon Emulsifier Co., Ltd.); “Eleminol JS-2” (trade name, manufactured by Sanyo Chemical Industries, Ltd.) "Latemuru S-120", "Latemuru S-180", "Latemuru S-180A", "Latemuru PD-104" (manufactured by Kao Corporation); "Adekaria Soap SR-10", "Adekaria Soap" “SE-10” (trade name, manufactured by ADEKA Corporation); “Aqualon KH-05”, “Aqualon KH-10”, “Aqualon HS-10” (trade name, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) Reactive anionic emulsifiers: “Adekalia Soap NE-10”, “Adekalia Soap ER-10”, “Adekalia Soap NE-20”, “Adekalia Soap ER-20”, “Adekalia Soap NE” “30”, “Adekaria soap ER-30”, “Adekaria soap NE-40”, “Adekaria soap ER-40” (trade name, manufactured by ADEKA Corporation); “Aquaron RN-10”, “Aquaron RN” Reactive nonionic emulsifiers such as “-20”, “AQUALON RN-30”, “AQUALON RN-50” (trade name, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.).
These emulsifiers may be used individually by 1 type, and may use 2 or more types together.

  As the polymerization initiator for obtaining the alkyl (meth) acrylate polymer (B), a known radical polymerization initiator can be used.

  Examples of the radical polymerization initiator include persulfate compounds such as potassium persulfate, sodium persulfate, and ammonium persulfate; azobisisobutyronitrile, 2,2′-azobis (2-methylbutyronitrile), 2 , 2′-azobis (2,4-dimethylvaleronitrile), 2,2′-azobis (4-methoxy-2,4-dimethylvaleronitrile), 2-phenylazo-4-methoxy-2,4-dimethylvaleronitrile Oil-soluble azo compounds such as 2,2′-azobis {2-methyl-N- [1,1-bis (hydroxymethyl) -2-hydroxyethyl] propionamide}, 2,2′-azobis {2- Methyl-N- [2- (1-hydroxyethyl)] propionamide}, 2,2′-azobis {2-methyl-N- [2- (1-hydroxybutyl)] propyl Pionamide}, 2,2′-azobis [2- (5-methyl-2-imidazolin-2-yl) propane] and its salts, 2,2′-azobis [2- (2-imidazolin-2-yl) propane And its salts, 2,2′-azobis [2- (3,4,5,6-tetrahydropyrimidin-2-yl) propane] and its salts, 2,2′-azobis {2- [1- (2 -Hydroxyethyl) -2-imidazolin-2-yl] propane} and salts thereof, 2,2′-azobis (2-methylpropionamidine) and salts thereof, 2,2′-azobis (2-methylpropyneamidine) And salts thereof, water-soluble azo compounds such as 2,2′-azobis [N- (2-carboxyethyl) -2-methylpropionamidine] and salts thereof; benzoyl peroxide, cumene hydro Okishido, t- butyl hydroperoxide, t- butyl peroxy-2-ethylhexanoate, and organic peroxides such as t-butyl peroxy isobutyrate.

  These radical polymerization initiators may be used alone or in combination of two or more. Moreover, when superposing | polymerizing by an emulsion polymerization method, reducing agents, such as sodium bisulfite, ferrous sulfate, ascorbate, can also be used in combination with the said radical polymerization initiator.

  The method for pulverizing the alkyl (meth) acrylate polymer (B) is not particularly limited, and can be appropriately selected depending on the polymerization method. For example, when the alkyl (meth) acrylate polymer (B) is obtained by emulsion polymerization, the pulverization method of the alkyl (meth) acrylate polymer (B) includes, for example, a coagulation method, a spray drying method, and a centrifugal separation. Method and freeze-drying method. Among these powdering methods, a coagulation method and a spray drying method are preferable from the viewpoint of homogeneity of the obtained alkyl (meth) acrylate polymer (B) powder.

  When powdering the alkyl (meth) acrylate polymer latex using the coagulation method, the alkyl (meth) acrylate polymer latex is brought into contact with the coagulant at 30 to 90 ° C. and coagulated with stirring. Thus, the alkyl (meth) acrylate polymer (B) can be pulverized by slurrying and drying. Examples of the coagulant used in the coagulation method include inorganic acids such as hydrochloric acid, sulfuric acid, nitric acid and phosphoric acid; organic acids such as formic acid and acetic acid; inorganic salts such as aluminum sulfate, magnesium sulfate and calcium sulfate; organics such as calcium acetate Examples include salts.

  When pulverizing the alkyl (meth) acrylate polymer latex using the spray drying method, the alkyl (meth) acrylate polymer latex is subjected to an inlet temperature of 120 to 220 ° C and an outlet temperature of 40 to 90 ° C. The alkyl methacrylate polymer can be pulverized by spray drying with a spray dryer. The outlet temperature is preferably 40 to 80 ° C. and more preferably 40 to 70 ° C. from the viewpoint of disintegration of the alkyl (meth) acrylate polymer (B) powder into primary particles. preferable.

  When recovering the alkyl (meth) acrylate polymer (B) from the latex, a mixed latex is prepared together with the latex of the crosslinked fine particles (A), and a mixed powder is obtained by a method such as a coagulation method or a spray drying method. It is also possible to knead this mixed powder with the thermoplastic resin (C).

  As the alkyl (meth) acrylate polymer (B), the same polymer may be used alone, or two or more polymers having different compositions, molecular weights, particle sizes, etc. may be used in combination.

  The mass average molecular weight of the alkyl (meth) acrylate polymer (B) is preferably 1,000 to 3,000,000, more preferably 3,000 to 500,000, and 5,000 to It is more preferably 100,000, and particularly preferably 10,000 to 50,000.

  When the mass molecular weight of the alkyl (meth) acrylate polymer (B) is 1,000 or more, the handleability of the resulting alkyl (meth) acrylate polymer (B) is excellent. Moreover, when the mass molecular weight of the alkyl (meth) acrylate polymer (B) is 3,000,000 or less, the dispersibility of the crosslinked fine particles (A) in the thermoplastic resin composition is excellent.

  The mass average molecular weight of the alkyl (meth) acrylate polymer (B) is measured by gel permeation chromatography.

  The method for adjusting the mass average molecular weight of the alkyl (meth) acrylate polymer (B) is not particularly limited, and examples thereof include a method for adjusting the amount of polymerization initiator and a method for adjusting the amount of chain transfer agent. .

Examples of the chain transfer agent include mercaptans such as n-dodecyl mercaptan, t-dodecyl mercaptan, n-octyl mercaptan, n-tetradecyl mercaptan, n-hexyl mercaptan, n-butyl mercaptan; carbon tetrachloride, ethylene bromide. And halogen compounds such as α-methylstyrene dimer.
These chain transfer agents may be used individually by 1 type, and may use 2 or more types together.

  The amount of chain transfer agent used can be appropriately adjusted according to the mass average molecular weight of the alkyl (meth) acrylate polymer (B), the type of chain transfer agent used, the composition ratio of the monomers, and the like.

  The thermoplastic resin composition of the present invention contains crosslinked fine particles (A), an alkyl (meth) acrylate polymer (B), and a thermoplastic resin (C). Examples of the thermoplastic resin (C) include polyolefin resin, polyvinyl chloride resin, polyester resin, polycarbonate resin, polystyrene resin, polyamide resin, and the like. These resins may be used alone or in combination of two or more. The thermoplastic resin (C) in the present invention does not have a crosslinked structure and is different from the crosslinked fine particles (A). Further, it is a thermoplastic resin that does not contain an alkyl (meth) acrylate polymer (B).

  The blending ratio of the thermoplastic resin composition of the present invention is not particularly defined and can be arbitrarily set according to the type and function of the crosslinked fine particles. For example, when the crosslinked fine particles (A) are used as a matting agent, the content of the crosslinked fine particles (A) is 1 to 70 parts by mass (however, the total amount of the thermoplastic resin composition is 100 parts by mass). ) Is preferable. When the content of the crosslinked fine particles (A) is 1 part by mass or more, a sufficient matting effect can be obtained. When the content of the crosslinked fine particles (A) is 70 parts by mass or less, the mixture can be stably and uniformly melt-kneaded. Moreover, as content of an alkyl (meth) acrylate type polymer (B), it is preferable that it is 0.1-20 mass parts However, The total compounding quantity of a thermoplastic resin composition shall be 100 mass parts. If content of an alkyl (meth) acrylate (B) is 0.1 mass part or more, the dispersibility of the crosslinked fine particle (A) in a thermoplastic resin composition can be improved. When the content of the alkyl (meth) acrylate (B) is 20 parts by mass or less, the dispersibility of the crosslinked fine particles (A) can be improved without significantly reducing the properties of the thermoplastic resin (C).

  The thermoplastic resin composition of the present invention may contain other additives as components other than the crosslinked fine particles (A), the alkyl (meth) acrylate polymer (B), and the thermoplastic resin (C). good. Examples of other additives include flame retardants, fillers, antioxidants, light stabilizers, lubricants, and foaming agents.

Examples of the flame retardant include “FR-1025M”, “FR-1524”, “FR-2124”, “F-2016”, “F-2300”, “F-2310”, “F-2300H” (product) Name, manufactured by ICL-IP Japan Co., Ltd.); “Frame Cut 120G”, “Frame Cut 121K”, “Frame Cut 122K” (trade name, manufactured by Tosoh Corporation); “SAYTEX RB-100”, “SAYTEX BT” Bromine-based flame retardants such as “-93”, “SAYTEX BT-93W”, “SAYTEX 8010”, “SAYTEX HP-7010P” (trade name, Albemarle Japan Co., Ltd.); "2200", "ADK STAB FP-2200S" (trade name, ADEKA Corporation); "Fire Cut P77 (Trade name, Suzuhiro Chemical Co., Ltd.) and other phosphate flame retardants; “TPP”, “TCP”, “TXP”, “CDP”, “CR-733S”, “CR-741”, “ “PX-200”, “TMCPP”, “CR-900”, “CR-509”, “CR-530”, “CR-504L” (trade name, Daihachi Chemical Industry Co., Ltd.); “ADK STAB PFR”, Phosphate-based flame retardants such as “ADK STAB FP-500” and “ADK STAB FP-600” (trade name, ADEKA Co., Ltd.); a flame retardant containing magnesium hydroxide as a main component, and aluminum hydroxide as a main component Examples include flame retardants and mixtures thereof.
These flame retardants may be used alone or in combination of two or more.

  Examples of the filler include calcium carbonate, talc, glass fiber, carbon fiber, magnesium carbonate, mica, kaolin, calcium sulfate, barium sulfate, titanium white, white carbon, and carbon black. These fillers may be used individually by 1 type, and may use 2 or more types together.

  As the antioxidant, known antioxidants such as hindered phenol antioxidants, sulfur antioxidants, phosphorus antioxidants and the like can be used. These antioxidants may be used alone or in combination of two or more.

  As the light stabilizer, known light stabilizers such as an ultraviolet absorber and a hindered amine light stabilizer can be used. These light stabilizers may be used alone or in combination of two or more.

  Among these light stabilizers, triazine-based ultraviolet absorbers are excellent in flame retardancy of molded products obtained by improving char-forming ability, and because of excellent flame retardancy of molded products obtained by radical scavenging, A hindered amine light stabilizer is preferred.

  Examples of the lubricant include sodium, calcium or magnesium salts of lauric acid, palmitic acid, oleic acid or stearic acid. These lubricants may be used individually by 1 type, and may use 2 or more types together.

  As the foaming agent, known foaming agents such as inorganic foaming agents, volatile foaming agents, and decomposable foaming agents can be used.

  Examples of the inorganic foaming agent include carbon dioxide, air, and nitrogen.

  Examples of volatile blowing agents include aliphatic hydrocarbons such as propane, n-butane, i-butane, pentane and hexane; cyclic aliphatic hydrocarbons such as cyclobutane and cyclopentane; trichlorofluoromethane and dichlorodifluoromethane. Halogenated hydrocarbons such as dichlorotetrafluoroethane, methyl chloride, ethyl chloride, and methylene chloride.

Examples of the decomposable foaming agent include azodicarbonamide, dinitrosopentamethylenetetramine, azobisisobutyronitrile, and sodium bicarbonate.
These foaming agents may be used individually by 1 type, and may use 2 or more types together.

  As a method for mixing the thermoplastic resin composition, known melt kneading such as extrusion kneading and roll kneading can be used.

  The melt kneading method is not particularly limited, and the crosslinked fine particles (A) of the present invention, the alkyl (meth) acrylate resin (B), and the thermoplastic resin (C) may be simultaneously melt kneaded. A masterbatch is prepared by melt-kneading the total amount of (A) and the alkyl (meth) acrylate resin (B) and a part of the thermoplastic resin (C), and then the masterbatch and the thermoplastic resin (C). The remainder may be melt kneaded.

The melt kneading temperature can be appropriately set according to the kind of the thermoplastic resin (C).
When the thermoplastic resin (C) is a polyolefin resin, the melt-kneading temperature is preferably 160 to 280 ° C, and more preferably 180 to 240 ° C.

  The molded article of the present invention is obtained by molding the thermoplastic resin composition of the present invention.

  As the molding method, a known molding method can be used, and examples thereof include extrusion molding, injection molding, calendar molding, blow molding, thermoforming, foam molding, and melt spinning.

  The molded article of the present invention is excellent in surface appearance and flame retardancy, and therefore suitable for sheet materials such as optical sheets, film materials such as food films, automobile members, household appliance members, medical members, building members, etc. It is.

EXAMPLES Hereinafter, although an Example demonstrates this invention concretely, this invention is not limited to these Examples.
In the examples, “parts” and “%” indicate “parts by mass” and “% by mass”.

(1) Mass average molecular weight Gel permeation chromatography (model name “HLC-8220”, manufactured by Tosoh Corporation), column (trade name “TSK-GEL SUPER”) using tetrahydrofuran-soluble content of alkyl methacrylate polymer as a sample HZM-M ”(manufactured by Tosoh Corporation) was used under the conditions of eluent tetrahydrofuran and measurement temperature of 40 ° C.
The mass average molecular weight was determined from a calibration curve using standard polystyrene.

(2) Dispersibility About the obtained molded body (film), the appearance is visually observed, the appearance defect points based on the dispersion failure of the crosslinked fine particles recognized on the film are counted, and the appearance defect points per meter are set as numerical values. evaluated.

(3) Surface gloss About the obtained molded object,
60 ° gloss was measured using a spectral color difference meter “SE2000 type” manufactured by Nippon Denshoku Industries Co., Ltd.

[Preparation of alkyl methacrylate polymer]
In a separable flask equipped with a thermometer, nitrogen introduction tube, cooling tube and stirring device, 225 parts of ion exchange water, 2.5 parts of sodium dodecylbenzenesulfonate, 0.0002 part of ferrous sulfate, disodium ethylenediaminetetraacetate 0.0006 part and 0.48 part of ascorbic acid were charged, and the inside of the separable flask was purged with nitrogen. Next, the internal temperature was raised to 73 ° C., and a mixture of 0.2 parts of cumene hydroperoxide, 1 part of n-octyl mercaptan, 98 parts of i-butyl methacrylate and 2 parts of n-butyl acrylate was added dropwise over 1 hour. Furthermore, it was kept at the same temperature for 1 hour to obtain an alkyl methacrylate polymer latex.

The obtained alkyl methacrylate polymer latex was cooled to 25 ° C., dropped into 500 parts of 70 ° C. hot water containing 5 parts of calcium acetate, and then heated to 90 ° C. for coagulation. The resulting coagulated product was separated and washed, and then dried at 60 ° C. for 12 hours to obtain an alkyl methacrylate polymer powder. The obtained alkyl methacrylate polymer had a mass average molecular weight of 30,000.
The obtained alkyl methacrylate polymer powder was designated as “B-1.”

As the crosslinked fine particles (A), “Methbrene F-410” (trade name, manufactured by Mitsubishi Rayon Co., Ltd.), the alkyl (meth) acrylate resin (B) as “B-1”, and the thermoplastic resin as a polypropylene resin. “NOVATEC FY-4” (trade name, manufactured by Nippon Polypro Co., Ltd.) was blended at the ratio shown in Table 1 and mixed by hand blending. Then, using a φ30 mm same-direction twin screw extruder (manufactured by Plastic Engineering Laboratory Co., Ltd., L / D = 30), extrusion is performed under the conditions of a screw rotation speed of 200 rpm and a cylinder temperature of 200 ° C. to obtain a thermoplastic resin composition. It was. The obtained thermoplastic resin composition was dried at 80 ° C. for 12 hours, and the screw rotation speed was 20 rpm in a single screw extruder (L / D = 30, manufactured by GM Engineering) attached with a T die. Film formation was performed under conditions of cylinder temperature: 200 ° C., T die temperature: 210 ° C. so that the film thickness was 500 μm and the film width was 10 cm. About the obtained film, the glossiness of the film and the number of foreign matters were evaluated by the above methods. The evaluation results are shown in Table 1.
[Comparative Example 1]

Kneading, film formation and evaluation were performed in the same manner as in Example 1 except that the alkyl (meth) acrylate polymer (B) was not blended. The evaluation results are shown in Table 1.
[Comparative Example 2]

Kneading, film formation and evaluation were carried out in the same manner as in Example 1 except that the crosslinked fine particles (A) were not blended. The evaluation results are shown in Table 1.
[Reference Example 1]

  Kneading, film formation and evaluation were carried out in the same manner as in Example 1 except that the crosslinked fine particles (A) and the alkyl (meth) acrylate polymer (B) were not blended. The evaluation results are shown in Table 1.

F-410: Cross-linked fine particle “Metablene F-410” (trade name, manufactured by Mitsubishi Rayon Co., Ltd.)
FY-4: Polypropylene resin “NOVATEC FY-4” (trade name, manufactured by Nippon Polypro Co., Ltd.)

  As is apparent from Table 1, the molded product obtained by molding the thermoplastic resin composition of the present invention is excellent in dispersibility of the crosslinked fine particles (A) and exhibits a high matting effect. On the other hand, in Comparative Example 1 that does not contain the alkyl (meth) acrylate (B), the dispersibility of the crosslinked fine particles (A) is low, so that the appearance defect is remarkably generated. Also, the matte effect is not sufficient. In Comparative Example 2 that does not contain the crosslinked fine particles (A), although no appearance defect occurs, the matte effect is not exhibited.

  From the above, it is apparent that molding with excellent surface appearance can be obtained without reducing the original function of the crosslinked fine particles by using the thermoplastic resin composition of the present invention.

  The molded product obtained by using the thermoplastic resin composition of the present invention is excellent in surface appearance while maintaining the original function of the crosslinked fine particles, so that it is a sheet material, a film material, an automobile member, a household appliance member, a medical device. It is suitable for construction members and building members.

Claims (5)

  A thermoplastic resin composition comprising crosslinked fine particles (A), an alkyl (meth) acrylate polymer (B) and a thermoplastic resin (C).   The thermoplastic resin composition according to claim 1, wherein the crosslinked fine particles (A) are a matting agent.   The thermoplastic resin composition according to claim 1 or 2, wherein the alkyl (meth) acrylate polymer (B) is an i-butyl methacrylate polymer.   The thermoplastic resin composition according to claim 1, wherein the thermoplastic resin (C) is a polyolefin resin.   The molded object obtained by shape | molding the thermoplastic resin composition of Claims 1-4.