JP2011137066A - Automobile interior part reduced with squeak noise - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide automobile interior parts which significantly reduced with squeak noise generated when parts rub against each other and maintain the favorable effect on reducing the squeak noise even when placed under high temperature for a long period of time without diminishing the effect on reducing the squeak noise and which are excellent in impact resistance and surface appearance of a molding thereof. <P>SOLUTION: The automobile interior part comprises a thermoplastic resin composition. The thermoplastic resin composition is obtained by blending (C) 0.1-30 pts.mass of at least one ethylenic polymer selected from a low-molecular weight polyethylene oxide (c1), an ultrahigh-molecular weight polyethylene (c2), and polytetrafluoroethylene (c3), based on the total 100 pts.mass of a component (A) and a component (B), with (A) 5-100 mass% of a rubber-reinforced styrenic resin and (B) 0-95 mass% of a vinyl-based polymer. The rubber-reinforced styrenic resin is obtained by polymerizing a vinyl-based monomer (A2) comprising an aromatic vinyl compound or an aromatic vinyl compound and another vinyl monomer copolymerizable with the aromatic vinyl compound in the presence of an ethylene-α-olefin-based rubbery polymer (A1). <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an automobile interior part, and more particularly, to an automobile interior part made of a thermoplastic resin composition in which the squeaking noise generated by contacting and rubbing with other parts is greatly reduced.

  ABS resin is widely used in the manufacture of automotive interior parts due to its excellent mechanical properties, heat resistance, moldability and the like.

  However, in the case where automobile interior parts made of ABS resin and the parts are in contact with and rubbed with chloroprene rubber, polyurethane, natural rubber, polyester or polyethylene lining sheets, foam, etc., due to vibration during driving, Sound (friction) may be generated. For example, a ventilator made of ABS resin is equipped with a valve shutter that uses chloroprene rubber foam or the like as a sealing material to adjust the air volume, and seals when the valve shutter is rotated to adjust the air volume. The wood and the ventilator case rub against each other. As described above, a squeaking noise may be generated even under a usage situation in which an ABS resin automobile interior part functionally rubs against other parts.

  Also, since ABS resin and ASA resin are amorphous plastics, they have a higher coefficient of friction compared to crystalline plastics such as polyethylene, polypropylene, and polyacetal, and are used for air conditioner outlets and car stereo buttons in automobiles. As described above, it is well known that a stick-slip phenomenon (Non-Patent Document 1) occurs and abnormal noise (stagnation sound) occurs when mated with a component made of another resin. These squeaking noises are a major cause of impairing comfort and quietness when riding, and reduction of squeaking noises has been strongly desired.

  Therefore, in order to prevent these squeaking noises, a method of applying Teflon (registered trademark) coating on the surface of the component, a method of attaching Teflon tape, a method of applying silicone oil, and the like have been performed. In addition to being very cumbersome and time-consuming, there is a problem that the effect does not last when placed under high temperature.

  Further, as a method for modifying the material itself used for automobile interior parts, for example, a technique (Patent Document 1) in which an organosilicon compound is blended with a resin made of polycarbonate resin and ABS resin, flame retardant, difficult A technology for blending a fuel aid and silicone oil (Patent Document 2), a technology for blending silicone oil in ABS resin, MBS resin and HIPS (High Impact Polystyrene) resin (Patent Document 3), and alkane in ABS resin A technique for blending a sulfonate surfactant (Patent Document 4) further blends ABS resin with a modified polyorganosiloxane having at least one reactive group selected from an epoxy group, a carboxyl group and an acid anhydride group, Disclosed is a technology (Patent Document 5) that is used for water-related parts in bathrooms and toilets. To have.

  However, the effect of reducing stagnation noise by these methods is not sufficient, and even if it shows a certain level of stagnation noise prevention effect immediately after molding, the effect is not long-lasting, especially when placed at high temperatures for a long time Had a problem that the effect was reduced.

Japanese Patent Publication No. 63-56267 Japanese Patent No. 2798396 Japanese Patent No. 2688619 Japanese Patent No. 2659467 JP 10-316833 A

Surface Science Vol.24, No.6, P328-333,2003.

  In view of such circumstances, the present invention significantly reduces the squeaking noise generated when the parts rub against each other, and maintains the squeaking noise reduction effect even when left under high temperature for a long time. An object of the present invention is to provide automobile interior parts made of a thermoplastic resin composition having excellent properties and surface appearance of molded products.

  As a result of intensive studies to solve the above-mentioned problems, the inventors have significantly reduced the occurrence of squeaking noise by adding a specific amount of a specific additive to a specific rubber-reinforced styrene-based resin, and high temperature. It has been found that even when left for a long time, the stagnation sound reduction effect is maintained without deteriorating, and the present invention has been completed.

That is, according to the present invention, an automobile interior part having the following characteristics is provided.
(1) (A) from an aromatic vinyl compound or an aromatic vinyl compound and other vinyl monomers copolymerizable with the aromatic vinyl compound in the presence of an ethylene / α-olefin rubbery polymer (A1) 5 to 100% by mass of a rubber-reinforced styrene resin formed by polymerizing a vinyl monomer (A2)
(B) 0 to 95% by mass of the vinyl polymer, and a total of 100 parts by mass of the component (A) and the component (B),
(C) 0.1 to 30 parts by mass of at least one ethylene polymer selected from low molecular weight oxidized polyethylene (c1), ultrahigh molecular weight polyethylene (c2), and polytetrafluoroethylene (c3). An automotive interior part comprising a thermoplastic resin composition.
(2) The above-mentioned automobile interior part, wherein the amount of the ethylene / α-olefin rubbery polymer (A1) is 3 to 40% by mass in a total of 100% by mass of the component (A) and the component (B).
(3) Further, (D) an aromatic vinyl compound or an aromatic vinyl compound and another vinyl monomer copolymerizable with the aromatic vinyl compound in the presence of the conjugated diene rubbery polymer (D1). A graft polymer obtained by polymerizing the vinyl monomer (D2),
The mass ratio of the ethylene / α-olefin rubber polymer (A1) and the conjugated diene rubber polymer (D1) is blended in a range of (A1) :( D1) = 5 to 95: 95-5. The above automotive interior parts.
(4) The automobile interior part described above, wherein the low molecular weight oxidized polyethylene (c1) has an acid value of 10 to 30 (mgKOH / g).
(5) The automobile interior part described above, wherein the ultra high molecular weight polyethylene (c2) has a molecular weight (measured by a solution viscosity method according to ASTM D4020) of 400,000 to 2.5 million.
(6) The automobile interior part described above, which is used for an automobile ventilator.

  According to the present invention, an impact resistance and molded article comprising a thermoplastic resin composition comprising the component (A), the component (B) and the component (C), and further comprising a thermoplastic resin composition containing the component (D). In addition to excellent surface appearance, the squeaking noise that occurs when parts rub against each other is remarkably reduced, and the squeaking noise reduction effect does not deteriorate even when left at high temperatures for a long time, and a good squeaking noise reduction effect is maintained. Automotive interior parts are obtained.

Hereinafter, the present invention will be described in detail.
In the present specification, “(co) polymerization” means homopolymerization and copolymerization, and “(meth) acryl” means acrylic and / or methacrylic.

The component (A) of the present invention is an aromatic vinyl compound or other vinyl monomer copolymerizable with the aromatic vinyl compound and the aromatic vinyl compound in the presence of the ethylene / α-olefin rubbery polymer (A1). It is a rubber-reinforced styrene resin obtained by polymerizing a vinyl monomer (A2) composed of a monomer. Examples of the ethylene / α-olefin rubbery polymer (A1) used here include an ethylene / α-olefin copolymer and an ethylene / α-olefin / non-conjugated diene copolymer. , An α-olefin having 3 to 20 carbon atoms is used. Specifically, propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-heptene, 1-octene, 1 -Decene, 1-dodecene, 1-hexadecene, 1-eicocene and the like. These α-olefins can be used alone or in combination of two or more. The number of carbon atoms of the α-olefin is preferably 3-20, more preferably 3-12, and even more preferably 3-8. When the carbon number exceeds 20, the copolymerizability is reduced, and the surface appearance of the molded product is reduced. It may not be enough. The mass ratio of ethylene: α-olefin is usually from 5 to 95:95 to 5, preferably from 50 to 90:50 to 10, more preferably from 60 to 95 from the viewpoints of impact resistance, molded product surface appearance and squeaking noise reduction. It is 88: 40-12, Most preferably, it is 70-85: 30-15.
Among these, from the viewpoint of reducing squeaking noise, an ethylene-propylene copolymer is preferable, and one having a melting point based on an ethylene chain is preferable.

  Non-conjugated dienes include alkenyl norbornenes, cyclic dienes and aliphatic dienes, with 5-ethylidene-2-norbornene and dicyclopentadiene being preferred. These non-conjugated dienes can be used alone or in combination of two or more. The ratio of the nonconjugated diene to the total amount of the rubbery polymer (A1) is usually 0 to 30% by mass, preferably 0 to 20% by mass, and more preferably 0 to 10% by mass. When the proportion of the non-conjugated diene exceeds 30% by mass, the molded appearance and the weather resistance tend to be inferior. The amount of unsaturated groups is preferably in the range of 40 or less in terms of iodine value. If the iodine value exceeds 40, the surface appearance and weather resistance of the molded product may not be sufficient.

The Mooney viscosity (ML _{1 + 4} , 100 ° C .; conforming to JISK6300) of the component (A1) of the present invention is usually 5 to 80, preferably 10 to 65, more preferably 15 to 45. If the Mooney viscosity exceeds 80, the fluidity of the resulting rubber-reinforced styrene resin is poor, and if it is less than 5, the impact resistance of the resulting molded product may be insufficient.

  The vinyl monomer (A2) polymerized in the presence of the ethylene / α-olefin rubber polymer (A1) can be copolymerized with an aromatic vinyl compound, or an aromatic vinyl compound and an aromatic vinyl compound. Other vinyl monomers. Examples of aromatic vinyl compounds include styrene, α-methylstyrene, o-methylstyrene, p-methylstyrene, vinyltoluene, β-methylstyrene, ethylstyrene, p-tert-butylstyrene, vinylxylene, vinylnaphthalene, and monochlorostyrene. Dichlorostyrene, monobromostyrene, dibromostyrene, fluorostyrene and the like. These can be used alone or in combination of two or more. Of these, styrene and α-methylstyrene are preferred.

  Other vinyl monomers copolymerizable with aromatic vinyl compounds include vinyl cyanide compounds, (meth) acrylate esters, maleimide compounds, and carboxyl groups, acid anhydride groups, hydroxyl groups, amino groups, amide groups. There are functional group-containing unsaturated compounds having one or more functional groups such as an epoxy group and an oxazoline group, and these can be used alone or in combination of two or more. Of these, vinyl cyanide compounds, (meth) acrylic acid esters, maleimide compounds, and carboxyl, acid anhydride, hydroxyl, and epoxy group-containing unsaturated compounds are preferred.

  Examples of the vinyl cyanide compound include acrylonitrile and methacrylonitrile. These can be used alone or in combination of two or more. Of these, acrylonitrile is preferred.

  (Meth) acrylates include methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, amyl acrylate, hexyl acrylate, octyl acrylate, 2-ethylhexyl acrylate, cyclohexyl acrylate, phenyl acrylate Acrylates such as benzyl acrylate; methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, amyl methacrylate, hexyl methacrylate, octyl methacrylate, 2-ethylhexyl methacrylate, dodecyl methacrylate, methacrylic acid And methacrylic acid esters such as cyclohexyl, phenyl methacrylate, and benzyl methacrylate. These can be used alone or in combination of two or more. Of these, methyl methacrylate and butyl acrylate are preferred.

Examples of maleimide compounds include maleimide, N-methylmaleimide, N-butylmaleimide, N-cyclohexylmaleimide, and N-phenylmaleimide. These can be used alone or in combination of two or more. Of these, N-cyclohexylmaleimide and N-phenylmaleimide are preferred.
As a method for introducing the monomer comprising the maleimide compound into the polymer, a method in which maleic anhydride is copolymerized in advance and then imidized is also preferably used.

  Examples of the carboxyl group-containing unsaturated compound include acrylic acid, methacrylic acid, ethacrylic acid, maleic acid, fumaric acid, itaconic acid, crotonic acid, and cinnamic acid, and these are used alone or in combination of two or more. be able to. Of these, acrylic acid and methacrylic acid are preferred.

  Examples of the acid anhydride group-containing unsaturated compound include maleic anhydride, itaconic anhydride, citraconic anhydride and the like, and these can be used alone or in combination of two or more. Of these, maleic anhydride is preferred.

  Examples of the hydroxyl group-containing unsaturated compound include hydroxystyrene, 3-hydroxy-1-propene, 4-hydroxy-1-butene, cis-4-hydroxy-2-butene, trans-4-hydroxy-2-butene, 3- Examples include hydroxy-2-methyl-1-propene, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, N- (4-hydroxyphenyl) maleimide, and these are used alone or in combination of two or more. can do. Of these, 2-hydroxyethyl methacrylate and 2-hydroxyethyl acrylate are preferred.

  Amino group-containing unsaturated compounds include aminoethyl acrylate, propylaminoethyl acrylate, dimethylaminomethyl acrylate, diethylaminomethyl acrylate, 2-dimethylaminoethyl acrylate, aminoethyl methacrylate, propylaminoethyl methacrylate, Dimethylaminomethyl methacrylate, diethylaminomethyl methacrylate, 2-dimethylaminoethyl methacrylate, phenylaminoethyl methacrylate, p-aminostyrene, N-vinyldiethylamine, N-acetylvinylamine, acrylicamine, methacrylamine, N-methyl An acrylic amine etc. are mentioned, These can be used individually or in combination of 2 or more types.

  Examples of the amide group-containing unsaturated compound include acrylamide, N-methylacrylamide, methacrylamide, and N-methylmethacrylamide. These can be used alone or in combination of two or more. Of these, acrylamide is preferred.

  Examples of the epoxy group-containing unsaturated compound include glycidyl acrylate, glycidyl methacrylate, and allyl glycidyl ether, and these can be used alone or in combination of two or more. Of these, glycidyl methacrylate is preferred.

  Examples of the oxazoline group-containing unsaturated compound include vinyl oxazoline and the like, and these can be used alone or in combination of two or more.

  The vinyl monomer (A2) is used in the aromatic vinyl compound or a combination of the aromatic vinyl compound and the other vinyl monomer copolymerizable with the aromatic vinyl compound, A combination of an aromatic vinyl compound and another vinyl monomer copolymerizable with the aromatic vinyl compound. More preferable combinations are aromatic vinyl compound / vinyl cyanide compound, aromatic vinyl compound / (meth) acrylic acid ester, aromatic vinyl compound / vinyl cyanide compound / (meth) acrylic acid ester, aromatic vinyl compound / maleimide. Compounds, particularly preferably styrene / acrylonitrile (60 to 90/10 to 40; mass ratio), styrene / methyl methacrylate (10 to 90/10 to 90; mass ratio), styrene / phenylmaleimide (50 to 95 / 5-50; mass ratio).

  Moreover, when combining a functional group containing unsaturated compound with the above-mentioned preferable monomer combination, it is 0-30 mass% normally with respect to 100 mass% of monomers whole quantity, Preferably it is 0-20 mass%, Furthermore, Preferably it is 0-15 mass%.

  The component (A) of the present invention is a rubber-reinforced styrene resin obtained by graft polymerization of the vinyl monomer (A2) in the presence of the ethylene / α-olefin rubber polymer (A1). However, usually, the (co) polymer of the vinyl monomer component (A2) is grafted to the component (A1) and not grafted to the component (A1) (A2). ) Component (co) polymers. However, this graft copolymer may contain a component (A1) to which the (co) polymer of the component (A2) is not grafted.

The component (A) of the present invention can be produced by a known polymerization method such as emulsion polymerization, solution polymerization, suspension polymerization, bulk polymerization, and a combination of these methods. In the presence of the coalescence (A1), the vinyl monomer component (A2) may be added and polymerized at once, or may be divided or continuously added for polymerization. Further, the rubbery polymer (A1) may be polymerized by adding the whole amount or a part thereof during the polymerization with the vinyl monomer (A2).
The amount of the ethylene / α-olefin rubber polymer (A1) used is usually 5 to 80% by mass in 100% by mass in total of the component (A1) and the vinyl monomer component (A2). In the case of emulsion polymerization, 10 to 70% by mass is preferable, and in the case of other polymerization methods, 5 to 40% by mass is preferable.

  When the component (A) of the present invention is obtained by emulsion polymerization, since the component (A1) is solid, it is necessary to emulsify. However, as an emulsification method, according to the description of JP-A-2002-265772, (A1) The components are dissolved in a solvent, an emulsifier, water, and the like are added and stirred, and then the solvent is distilled off to obtain a latex of component (A1). According to the method used for producing the component A) and JP-A-2006-45467, the component (A1), emulsifier, water and the like are added to the extruder and kneaded, and then added to warm water to obtain a latex, and then (A1) A method of using a crosslinked rubber latex obtained by subjecting a component to a crosslinking reaction in the production of the component (A) of the present invention can be used.

  When the component (A) is produced by emulsion polymerization in the presence of the crosslinked rubber latex of the component (A1) obtained by the above method, a polymerization initiator, a continuous transfer agent, an emulsifier, water, etc. are used. Examples of polymerization initiators include organic peroxides such as cumene hydroperoxide, diisopropylbenzene hydroperoxide, paramentane hydroperoxide, and reducing agents represented by sugar-containing pyrophosphate prescription, sulfoxylate prescription, etc. A redox polymerization initiator by a combination of: persulfate such as potassium persulfate is used. The polymerization initiator is usually added all at once or continuously to the reaction system.

  Examples of chain transfer agents include octyl mercaptan, n-dodecyl mercaptan, tert-dodecyl mercaptan, n-hexyl mercaptan, n-hexyl mercaptan, n-tetradecyl mercaptan, tert-tetradecyl mercaptan, and other mercaptans; terpinolenes, α- Examples include methylstyrene dimer, tetraethylthiuram sulfide, acrolein, methacrolein, allyl alcohol, 2-ethylhexylthioglycol and the like. These can be used alone or in combination of two or more.

  Examples of the emulsifier include anionic surfactants and nonionic surfactants. Anionic surfactants include higher alcohol sulfates; alkylbenzene sulfonates such as sodium dodecylbenzene sulfonate; aliphatic sulfonates such as sodium lauryl sulfate; potassium stearate, potassium oleate, potassium laurate, etc. Aliphatic carboxylates; rosinates, phosphates and the like. Examples of nonionic surfactants include polyethylene glycol alkyl ester compounds and alkyl ether compounds. These can be used alone or in combination of two or more.

  Emulsion polymerization can be carried out under known conditions depending on the types of monomer components and polymerization initiators used. The latex obtained by this emulsion polymerization can usually recover the polymer component as a powder by a coagulation / washing / drying method, a spray drying method or the like. Examples of the coagulant used for the coagulation include inorganic salts such as calcium chloride, magnesium sulfate, magnesium chloride, aluminum sulfate, and sodium chloride; inorganic acids such as sulfuric acid and hydrochloric acid; organic acids such as acetic acid, lactic acid, and citric acid, and the like. Used. These can be used alone or in combination of two or more. Further, depending on the required performance, washing may be carried out after adding an alkali component or an acid component after coagulation to neutralize it.

When the component (A) of the present invention is produced by solution polymerization, a solvent, a polymerization initiator, a chain transfer agent and the like are usually used.
Examples of the solvent include inert polymerization solvents used in known radical polymerization, for example, aromatic hydrocarbons such as ethylbenzene and toluene; ketones such as methyl ethyl ketone and acetone; halogenated hydrocarbons such as dichloroethylene and carbon tetrachloride. Acetonitrile, dimethylformamide, N-methylpyrrolidone and the like can be used. These can be used alone or in combination of two or more.

  Examples of the polymerization initiator include ketone peroxide, diallyl peroxide, diacyl peroxide, peroxy ester, hydroperoxide, benzoyl peroxide, lauroyl peroxide, tert-butyl peroxylaurate, tert-butyl peroxymonocarbonate, etc. Organic peroxides; azo polymerization initiators such as 2,2′-azobis (isobutyronitrile) and the like. Examples of the chain transfer agent include mercaptans, terpinolene, α-methylstyrene dimer, and the like. These can be used alone or in combination of two or more.

  The solution polymerization can be performed under known conditions, but is usually performed in the range of 80 to 140 ° C.

  Also in the case of bulk polymerization and suspension polymerization, known methods can be applied. As the polymerization initiator and chain transfer agent used in these methods, the compounds exemplified in the solution polymerization can be used.

  The graft ratio of the rubber-reinforced styrene resin (A) thus obtained is usually 10 to 150% by mass, preferably 20 to 120% by mass. When this graft ratio is less than 10% by mass and exceeds 150% by mass, impact resistance may be lowered.

The graft ratio can be determined by the following formula.
Graft ratio (mass%) = [(ST) / T] × 100

  In the above formula, 1 g of rubber-reinforced styrene resin (A) is added to 20 ml of acetone, shaken for 2 hours with a shaker at 25 ° C., and centrifuged at 5 ° C. This is the mass (g) of the insoluble matter obtained by centrifuging for 60 minutes with a separator (rotation speed: 23,000 rpm) and separating the insoluble matter and the soluble matter, and T is a rubber-reinforced styrene resin (A) It is the mass (g) of the rubber-like polymer (A1) contained in 1 gram. The mass of the rubbery polymer (A1) can be obtained by a method of calculating from the polymerization prescription and the polymerization conversion rate, a method of obtaining from an infrared absorption spectrum (IR), or the like.

  In addition, the intrinsic viscosity [η] (measured in methyl ethyl ketone at 30 ° C.) of the acetone-soluble component of the rubber-reinforced styrene resin (A) is usually 0.1 to 1.5 dl / g, preferably 0. .2 to 1.0 dl / g. When the intrinsic viscosity [η] is within the above range, the balance between physical properties of molding processability and impact resistance is excellent. The intrinsic viscosity can be adjusted by appropriately selecting the type and amount of chain transfer agent used during production, the type and amount of polymerization initiator, the polymerization temperature, and the like.

  The vinyl polymer as the component (B) of the present invention is a homopolymer or copolymer obtained by polymerizing one or two or more vinyl monomers, and the vinyl polymer used here. As the monomer, any of the aromatic vinyl compound and other vinyl monomers copolymerizable with the aromatic vinyl compound described in the monomer (A2) of the component (A) can be used.

  A preferred combination of vinyl monomers in the component (B) of the present invention is a combination of an aromatic vinyl compound and another vinyl monomer copolymerizable with the aromatic vinyl compound. More preferable combinations are aromatic vinyl compound / vinyl cyanide compound, aromatic vinyl compound / (meth) acrylic acid ester, aromatic vinyl compound / vinyl cyanide compound / (meth) acrylic acid ester, aromatic vinyl compound / maleimide. Compounds, particularly preferably styrene / acrylonitrile (60 to 90/10 to 40; mass ratio), styrene / methyl methacrylate (10 to 90/10 to 90; mass ratio), styrene / phenylmaleimide (50 to 95 / 5-50; mass ratio), α-methylstyrene / acrylonitrile / styrene (50-80 / 20-40 / 0-10; mass ratio), styrene / butyl acrylate / methyl methacrylate (0-40 / 5-30) / 30 to 95; mass ratio). Here, the copolymer composed of an aromatic vinyl compound / maleimide compound includes one obtained by imidizing an acid anhydride of an aromatic vinyl compound / maleic anhydride copolymer with an amine compound (for example, aniline). In this case, the acid anhydride may not be completely imidized and part of the acid anhydride may remain, but this is also included in the aromatic vinyl compound / maleimide compound copolymer.

  Moreover, when combining a functional group containing unsaturated compound with the above-mentioned preferable monomer combination, it is 0-30 mass% normally with respect to 100 mass% of monomers whole quantity, Preferably it is 0-20 mass%, Furthermore, Preferably it is 0-15 mass%.

The vinyl polymer (B) of the present invention can be produced by known polymerization methods such as emulsion polymerization, solution polymerization, bulk polymerization, suspension polymerization, and a polymerization method combining these.
As the polymerization initiator, chain transfer agent, solvent and emulsifier used in the above various production methods, all of those described in the component (A) can be used, and in the solution polymerization and bulk polymerization, the polymerization initiator is used. What was manufactured by thermal polymerization can also be used without using.

  The intrinsic viscosity [η] (measured in methyl ethyl ketone at 30 ° C.) of the component (B) of the present invention is usually 0.1 to 1.5 dl / g, preferably 0.2 to 1.0 dl / g. When the intrinsic viscosity [η] is within the above range, the balance between molding processability and impact resistance is excellent. The intrinsic viscosity can be adjusted by appropriately selecting the type and amount of chain transfer agent used during production, the type and amount of polymerization initiator, the polymerization temperature, and the like.

  The component (C) of the present invention is at least one ethylene polymer selected from low molecular weight oxidized polyethylene (c1), ultrahigh molecular weight polyethylene (c2), and polytetrafluoroethylene (c3).

  The low molecular weight polyethylene oxide (c1) has a number average molecular weight modified with a carboxylic acid group and / or an acid anhydride group (measured by GPC method) of 800 to 10,000, preferably 800 to 6,000, more preferably. Is from 1,000 to 5,000, particularly preferably from 1,200 to 4,000. The acid value representing the addition amount of the acid component is usually 1 to 40 (mg KOH / g), preferably 10 to 40 (mg KOH / g), more preferably 10 to 35 (mg KOH / g), and particularly preferably 10 ~ 30 (mg KOH). If the molecular weight is less than 800, the effect of improving the stagnation noise is reduced, while if it exceeds 10,000, the impact resistance may be inferior. Further, if the acid value is less than 1, the effect of improving the squeaking noise is small, and if it exceeds 40, appearance defects such as silver streaks may occur at the time of molding, which is not preferable.

  Low molecular weight oxidized polyethylene (c1) is a known method (1) a method in which low molecular weight polyethylene is oxidized in air to generate carboxylic acid groups, and (2) ethylene and carboxylic acid group-containing unsaturated compounds and / or acid anhydrides. A method of copolymerizing a physical group-containing unsaturated compound, and (3) adding a carboxylic acid group-containing unsaturated compound and / or an acid anhydride group-containing unsaturated compound and an organic peroxide in a molten state of low molecular weight polyethylene. It can be produced by a method of adding an unsaturated compound.

Such low molecular weight polyethylene oxide (c1) is manufactured by Sanyo Chemical Industries, Ltd. Sun Wax E-310, E-330, E-250P, LEL-400P (EX) (all trade names), Umex (trade name) 2000 Commercially available products can be obtained as Ricole H12, H22 (all trade names), Rico Wax (trade names) PED521, PED522, PED153, PED191, PED821, PED822 (all trade names) manufactured by Clariant.
Low molecular weight acid value polyethyleneylene (c1) can be used individually or in combination of 2 or more types.

  The ultra high molecular weight polyethylene (c2) is polyethylene having an average molecular weight of 400,000 to 6.5 million as measured by a solution viscosity method in accordance with ASTM D4020, and a preferable average molecular weight is 400,000 to 3.5 million, more preferably 400,000 to 2.5 million. Even when blended with the component (A) and the component (B) of the present invention and melt-kneaded, the ultrahigh molecular weight polyethylene (c2) of the present invention exists in an unmelted state, so that a powdery form should be used. Preferably, the average particle size measured by the Coulter counter method is preferably 50 μm or less, more preferably 5 to 40 μm.

Ultra high molecular weight polyethylene (c2) is made by Mitsui Chemicals Hi-Zex Million C30S, 145M, 240S, 240M, 320M, 340M, 530M (all trade names), and Mipelon (trade name) with a smaller average particle size. XM-220, XM-221U (both are trade names) and the like are available as commercial products.
The ultrahigh molecular weight polyethylene (c2) can be used alone or in combination of two or more.

Polytetrafluoroethylene (c3) is usually used as a dry lubricant. Preferably, it is in the form of fine powder, and the particle diameter of the fine powder is an average particle diameter of 0.1 to 100 μm by a method of measuring a dispersion liquid dispersed in perchlorethylene by a light transmission method. The melting point of the polytetrafluoroethylene fine powder is preferably 320 ° C. or higher by DSC measurement. Since the polytetrafluoroethylene fine powder is easily re-agglomerated, some of it has been subjected to a treatment such as a baking treatment in order to make it difficult to re-agglomerate, and these can be preferably used. Such polytetrafluoroethylenes are Daikin Industries' Lubron L-5 and L-2 (both trade names), Asahi IC Fluoropolymers L150J, L169J, L170J and L172J (all trade names), Mitsui A commercially available product can be obtained as Teflon TLP-10F-1 (trade name) manufactured by DuPont Fluorochemicals.
Polytetrafluoroethylene (c3) can be used alone or in combination of two or more.

  The low molecular weight oxidized polyethylene (c1), ultrahigh molecular weight polyethylene (c2) and polytetrafluoroethylene (c3), which are the component (C) of the present invention, can be used alone or in combination of two or more. Preferred combinations when used in combination are a combination of low molecular weight oxidized polyethylene (c1) and polytetrafluoroethylene (c3), and a combination of low molecular weight oxidized polyethylene (c1) and ultrahigh molecular weight polyethylene (c2).

  The amount of the rubber-reinforced styrene-based resin (A) component used in the thermoplastic resin composition of the present invention is 5 to 100 parts by mass with respect to a total of 100 parts by mass of the component (A) and the component (B), The amount is preferably 7 to 90 parts by mass, more preferably 10 to 80 parts by mass, and particularly preferably 15 to 70 parts by mass. Inferior.

  The usage-amount of the said vinyl-type polymer (B) component in the thermoplastic resin composition of this invention is 0-95 mass parts with respect to a total of 100 mass parts of (A) component and (B) component. Preferably it is 10-93 mass parts, More preferably, it is 20-90 mass parts, Most preferably, it is 30-85 mass parts. If the amount used exceeds 95 parts by mass, the squeaking noise is not reduced and the impact resistance is inferior.

  The amount of the ethylene / α-olefin rubber polymer (A1) in a total of 100 parts by mass of the component (A) and the component (B) of the present invention is impact resistance, molded product surface appearance and squeaking noise reduction effect. It is preferable that it is 3-40 mass parts from a viewpoint.

  The usage-amount of the said (C) component in the thermoplastic resin composition of this invention is 0.1-30 mass parts with respect to a total of 100 mass parts of the said (A) component and the said (B) component, Preferably When the low molecular weight polyethylene oxide (c1) is used, it is more preferably 0.3 to 5 parts by mass, particularly preferably 0.3 to 3 parts by mass. When using ultra high molecular weight polyethylene (c2), it is more preferably 1 to 20 parts by mass, particularly preferably 5 to 20 parts by mass. When polytetrafluoroethylene (c3) is used, it is more preferably 1 to 25 parts by mass, particularly preferably 3 to 20 parts by mass. If the amount of component (C) used is less than 0.1 parts by mass, the squeaking noise is not reduced, and if it exceeds 30 parts by mass, the impact resistance and the molded product surface appearance are inferior.

  The component (D) of the present invention includes an aromatic vinyl compound or another vinyl monomer copolymerizable with the aromatic vinyl compound and the aromatic vinyl compound in the presence of the conjugated diene rubbery polymer (D1). Is a graft polymer obtained by polymerizing a vinyl monomer (D2), and the conjugated diene rubber polymer (D1) used here is a homopolymer such as polybutadiene or polyisoprene; styrene・ Butadiene random copolymers, styrene / butadiene / styrene block copolymers, butadiene copolymers such as acrylonitrile / butadiene random copolymers; styrene / isoprene random copolymers, styrene / isoprene / styrene block copolymers, etc. These areoprene-based copolymers. These can be used alone or in combination of two or more. The diene rubbery polymer (D1) may be a crosslinked polymer or an uncrosslinked polymer. Particularly preferred components (D1) are a polybutadiene homopolymer and a styrene-butadiene random copolymer.

  The aromatic vinyl compound used as the vinyl monomer (D2), or the aromatic vinyl compound and the other vinyl compound copolymerizable with the aromatic vinyl compound are the vinyl monomers described in the component (A). All bodies (A2) can be used. Moreover, these can be used individually or in combination of 2 or more types.

  The vinyl monomer (D2) is preferably a combination of an aromatic vinyl compound and another vinyl monomer copolymerizable with the aromatic vinyl compound. More preferable combinations are aromatic vinyl compound / vinyl cyanide compound, aromatic vinyl compound / (meth) acrylic acid ester, aromatic vinyl compound / vinyl cyanide compound / (meth) acrylic acid ester, aromatic vinyl compound / maleimide. Compounds, particularly preferably styrene / acrylonitrile (60 to 90/10 to 40; mass ratio), styrene / methyl methacrylate (10 to 90/10 to 90; mass ratio), styrene / phenylmaleimide (50 to 95 / 5-50; mass ratio).

  Moreover, when combining a functional group containing unsaturated compound with the above-mentioned preferable monomer combination, it is 0-30 mass% normally with respect to 100 mass% of monomers whole quantity, Preferably it is 0-20 mass%, Furthermore, Preferably it is 0-15 mass%.

  The component (D) of the present invention is a graft polymer obtained by graft polymerization of the vinyl monomer (D2) in the presence of the conjugated diene rubbery polymer (D1). Usually, the (co) polymer of the monomer component (D2) is grafted to the component (D1) and the (co) weight of the component (D2) not grafted to the component (D1) Includes coalescence. However, this graft copolymer may contain (D1) component to which (D2) component (co) polymer is not grafted.

The component (D) of the present invention can be produced by a known polymerization method such as emulsion polymerization, solution polymerization, suspension polymerization, bulk polymerization, and a combination of these methods. In the presence of the coalescence, the vinyl monomer component (D2) may be added at once for polymerization, or may be divided or continuously added for polymerization. The rubbery polymer (D1) may be polymerized by adding all or part of the rubber polymer (D1) during the polymerization with the vinyl monomer (D2).
The amount of the conjugated diene rubber polymer (D1) used is usually 5 to 70% by mass in the total 100% by mass of the component (D1) and the vinyl monomer component (D2). In the case of 10 to 70% by mass, the case of other polymerization methods is preferably 5 to 40% by mass.

  As the method for producing the component (D) of the present invention, those obtained by emulsion polymerization are particularly preferred from the viewpoints of impact resistance and molded product surface appearance of the obtained thermoplastic resin composition. The rubber particle diameter of the conjugated diene rubbery polymer (D1) latex used here is 50 to 800 nm, preferably 100 to 700 nm in terms of volume average particle diameter.

  (D) Although a polymerization initiator, a serial transfer agent, an emulsifier, water, etc. are used when manufacturing a component by emulsion polymerization, all what was described by (A) component can be used.

  Emulsion polymerization can be carried out under known conditions depending on the types of monomer components and polymerization initiators used. The latex obtained by this emulsion polymerization can usually recover the polymer component as a powder by a coagulation / washing / drying method, a spray drying method or the like. As the coagulant used for the coagulation, all of those described above can be used. Further, depending on the required performance, washing may be carried out after adding an alkali component or an acid component after coagulation to neutralize it.

When the component (D) of the present invention is produced by solution polymerization, a solvent, a polymerization initiator, a chain transfer agent and the like are usually used, but all of those described in the component (A) can be used.
The solution polymerization can be performed under known conditions, but is usually performed in the range of 80 to 140 ° C.

  Also in the case of bulk polymerization and suspension polymerization, known methods can be applied. As the polymerization initiator and chain transfer agent used in these methods, the compounds exemplified in the solution polymerization can be used.

  The graft ratio of the graft polymer (D) thus obtained is usually 30 to 200% by mass, preferably 40 to 100% by mass. When this graft ratio is less than 30% by mass and more than 200% by mass, impact resistance may be lowered. The graft ratio can be determined by the above formula.

  The intrinsic viscosity [η] (measured in methyl ethyl ketone at 30 ° C.) of the acetone soluble part of the graft polymer (D) is usually 0.1 to 1.5 dl / g, preferably 0.2 to 1. 0.0 dl / g. When the intrinsic viscosity [η] is within the above range, the balance between physical properties of molding processability and impact resistance is excellent. The intrinsic viscosity can be adjusted by appropriately selecting the type and amount of chain transfer agent used during production, the type and amount of polymerization initiator, the polymerization temperature, and the like.

  When the components (A) and (D) of the present invention are used in combination, the mass ratio of the ethylene / α-olefin rubber polymer (A1) to the conjugated diene rubber polymer (D1) is (A1) :( D1) is preferably used in the range of 5 to 95:95 to 5 from the viewpoints of impact resistance, molded product surface appearance and squeaking noise reduction effect, more preferably 40 to 90:60 to 10, and particularly preferably 50. ~ 88: 50-12. Moreover, the total amount of the ethylene / α-olefin rubber polymer (A1) and the conjugated diene rubber polymer (D1) in a total of 100 parts by mass of the component (A), the component (B), and the component (D). Is preferably 3 to 40 parts by mass, particularly from the viewpoint of impact resistance.

  In the thermoplastic resin composition of the present invention, if necessary, a filler, a nucleating agent, a lubricant, a heat stabilizer, an antioxidant, an ultraviolet absorber, a flame retardant, an anti-aging agent, a plasticizer, an antibacterial agent, Various additives such as colorants (pigments, dyes, etc.) and antistatic agents can be contained within a range that does not impair the object of the present invention.

  Moreover, a well-known inorganic or organic filler can be mix | blended with the thermoplastic resin composition of this invention. The filler used here is glass fiber, glass flake, glass fiber milled fiber, glass powder, glass bead, hollow glass bead, carbon fiber, carbon fiber milled fiber, silver, copper, brass, iron, etc. Powder or fibrous material, carbon black, tin-coated titanium oxide, tin-coated silica, nickel-coated carbon fiber, talc, calcium carbonate, calcium carbonate whisker, wollastonite, mica, kaolin, montmorillonite, hextrite, zinc oxide whisker, titanium There are potassium acid whisker, aluminum borate whisker, plate aluminum, plate silica and organically treated smectite, aramid fiber, phenol resin, polyester fiber, etc., and these can be used alone or in combination of two or more. .

Furthermore, for the purpose of improving the dispersibility of the filler, those treated with a known coupling agent, surface treatment, sizing agent, etc. can be used. With known coupling agents, surface treatment agents, sizing agents, etc. What was processed can be used. Known coupling agents include silane coupling agents, titanate coupling agents, aluminum coupling agents and the like. These can be used alone or in combination of two or more.
The said inorganic or organic filler is normally used in 1-200 mass parts with respect to 100 mass parts of the thermoplastic resin composition of this invention.

  Furthermore, the thermoplastic resin composition of the present invention includes other polymers such as other polyolefin resins, thermoplastic aromatic polyester resins, thermoplastic aliphatic polyesters, thermoplastic polyurethanes, polycarbonates depending on the required performance. Polyphenylene sulfide, polyamide, polyamide elastomer, polyester elastomer, polyolefin elastomer, polyurethane elastomer and the like can be appropriately blended.

  The thermoplastic resin composition of the present invention is prepared by mixing each component at a predetermined mixing ratio using a tumbler mixer, a Henschel mixer, etc. It can be produced by melt-kneading under suitable conditions using a mixer. A preferred kneading method is a method using an extruder. Furthermore, when each component is kneaded, each component may be kneaded in a lump or may be kneaded in multiple stages. In addition, after knead | mixing with a Banbury mixer, a kneader, etc., it can also pelletize with an extruder. Moreover, it is preferable to supply the fibrous material among the fillers from the middle of the extruder using an addition method such as a side feeder in order to prevent cutting during kneading. The melt kneading temperature is usually in the range of 180 to 300 ° C.

  The automobile interior part of the present invention is obtained by molding the thermoplastic resin composition. There is no limitation on the method for producing the automobile interior part of the present invention comprising the thermoplastic resin composition, and injection molding, injection compression molding, gas assist molding, press molding, calendar molding, T-die extrusion molding, and profile extrusion molding. It can be produced by a known method such as film molding.

There are no particular limitations on the other members that come into contact with the automotive interior parts of the present invention. For example, thermoplastic resins, thermosetting resins, rubbers, organic materials, inorganic materials, metal materials containing the rubber-reinforced styrene resin of the present invention. Etc.
Examples of the thermoplastic resin include polyvinyl chloride, polyethylene, polypropylene, ABS resin, AES resin, ASA resin, polystyrene, high impact polystyrene, ethylene-vinyl acetate copolymer, polyamide (PA), and polybutylene terephthalate (PBT). ), Aliphatic polyester such as polyethylene terephthalate, polycarbonate (PC), polylactic acid, PC and / or PBT / ABS resin, PC and / or PBT / AES resin, PA / ABS resin, PA / AES resin and the like. These can be used alone or in combination of two or more.

  Examples of the thermosetting resin include phenol resin, epoxy resin, urea resin, melamine resin, unsaturated polyester resin, and thermosetting polyurethane. These can be used alone or in combination of two or more.

  Rubbers include chloroprene rubber, polybutadiene rubber, ethylene / propylene rubber, styrene / butadiene block copolymer, hydrogenated styrene / butadiene block copolymer, styrene / isoprene block copolymer, hydrogenated styrene / isoprene system. Examples include various synthetic rubbers such as block copolymers, natural rubber, and the like. These can be used alone or in combination of two or more.

  Organic materials include, for example, insulation board, MDF (medium fiber board), hard board, particle board, lumbar core, LVL (single board laminate), OSB (orientation board), PSL (pararam), WB (wafer) Board), hard fiberboard, soft fiberboard, lumbar core plywood, special core-plywood, veneer core-veneer board, laminated sheet / board of paper impregnated with tap resin, (old) fine small pieces / wires crushed paper etc. The board which mixed the adhesive agent with the body and heat-compressed, various woods, etc. are mentioned. These can be used alone or in combination of two or more.

Examples of the inorganic material include calcium silicate board, flexible board, homocement board, gypsum board, sizing gypsum board, gypsum lath board, decorative gypsum board, composite gypsum board, various ceramics, and glass. These can be used alone or in combination of two or more.
Furthermore, iron, aluminum, copper, various alloys, etc. are mentioned as a metal material. These can be used alone or in combination of two or more.
Among the above-mentioned other members that are in contact with the automobile interior part of the present invention, the thermoplastic resin, the thermosetting resin, and the rubber are preferable, and the effect of reducing the squeaking noise that is the object of the present invention is preferable. Preferably, it is a composition with ABS resin, AES resin, ASA resin, and PC.

  The automotive interior parts of the present invention can greatly reduce the squeaking noise generated by contacting and rubbing with parts made of other materials, such as door trim, door lining, pillar garnish, console, door pocket, ventilator, Meter visor, instrument panel upper garnish, instrument panel garnish, A / T indicator, on / off switch (slide part, slide plate), grill front defroster, grill side defroster, lid cluster, cover instroyer, masks (mask switch, mask radio Etc.), glove box, pockets (pocket deck, pocket card, etc.), steering wheel horn pad, etc. Among them, it can be suitably used as an automobile ventilator, and can be particularly suitably used as a plate-shaped blade, a bulk shutter, or the like of an automobile ventilator. It is suitable for a part having such a fitting part with another member.

  Hereinafter, the present invention will be described in more detail with reference to examples. However, the present invention is not limited to such examples as long as the gist of the present invention is not exceeded. In the examples, parts and% are: Unless otherwise specified, it is based on mass.

(1) Evaluation method:
The evaluation and measurement of various physical properties in Examples and Comparative Examples were based on the following methods.

(1-1) Evaluation of stagnation sound Using an injection molding machine “J-100E” (model name) manufactured by Nippon Steel Co., Ltd., the thermoplastic resin composition described in Table 1 and PC / ABS manufactured by Technopolymer Co., Ltd. An ISO dumbbell test piece made of the resin “CK43” (trade name) was injection-molded, and 5 ISO dumbbell test pieces made of the thermoplastic resin composition shown in Table 1 and an ISO dumbbell test piece 5 made of “CK43” The sheets were alternately overlapped, and the both ends were twisted by hand to evaluate the state of generation of the squeaking noise, and the squeaking sound evaluation-1 was obtained. Evaluation was performed 5 times, and determination was performed based on the following evaluation criteria. Thereafter, the test piece was left in a gear oven at 80 ° C. for 600 hours, and the same evaluation as described above was performed to obtain a squeaking sound evaluation-2.
(Double-circle): There was no generation | occurrence | production of a squeaking sound in all five evaluations.
O: The occurrence of itching was slight in all five evaluations.
(Triangle | delta): The case where generation | occurrence | production of a squeaking sound was remarkable was contained in five evaluations.
X: In all five evaluations, the generation of itching sound was significant.

(1-2) Impact resistance (falling weight impact strength):
Using an electric injection molding machine “Erject NEX30” (model) manufactured by Nissei Plastic Industrial Co., Ltd., a flat test piece of 80 mm × 55 mm × 1.6 mm made of the thermoplastic resin composition shown in Table 1 is injected. Molded. The cylinder temperature of the molding machine was 240 ° C., and the mold temperature was 80 ° C.
Next, using the Shimadzu hydro-shot / high-speed puncture impact tester “HITS-P10” (model name) manufactured by Shimadzu Corporation, the specimen was punched out under the following conditions, and the fracture energy (J) was measured.
Measurement temperature: 23 ° C
Punching speed: 5.6 mm / s
Strike tip r of punching test jig: 12.7 mm

(1-3) Molded product surface appearance:
The surface state of the test piece for measuring the falling weight impact strength was visually observed and evaluated according to the following criteria.
◯: Good with no appearance defects such as flow marks.
X: Appearance defects such as a flow mark are remarkable and appearance is inferior.

(2) (A) Component (2-1) Production Example 1: Polymer A-1 (ethylene / propylene rubbery polymer / styrene / acrylonitrile copolymer)
In a 20 liter stainless steel autoclave equipped with a ribbon-type stirring blade, auxiliary agent addition device, thermometer, etc., ethylene / propylene rubber (ethylene / propylene = ethylene / propylene rubber) as an ethylene / α-olefin rubber polymer (A1) 78/22 (%), Mooney viscosity (ML _{1 + 4} , 100 ° C.) 20) 22 parts, vinyl monomer (A2) as styrene 55 parts, acrylonitrile 23 parts, and tert-dodecyl mercaptan 0.5 parts Then, 110 parts of toluene was charged, the internal temperature was raised to 75 ° C., and the contents of the autoclave were stirred for 1 hour to obtain a uniform solution. Thereafter, after sufficiently purging with nitrogen, 0.45 part of tert-butylperoxyisopropyl monocarbonate was added, and after the internal temperature was further raised to 110 ° C., this temperature was maintained, The polymerization reaction was carried out at a stirring speed of 100 rpm. From 4 hours after the start of the polymerization reaction, the internal temperature was raised to 120 ° C., and the reaction was further continued for 2 hours while maintaining this temperature to complete the polymerization reaction. Thereafter, the internal temperature was cooled to 100 ° C., 0.2 part of octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenol) -propionate was added, and then the reaction mixture was extracted from the autoclave, Unreacted substances and the solvent were distilled off by distillation, and further, the volatile matter was substantially devolatilized by using an extruder with a vent having a screw diameter of 40 mm (cylinder temperature: 220 ° C., vacuum degree: 760 mmHg) to pelletize the polymer A- 1 was obtained. The graft ratio of the polymer A-1 was 70%, the intrinsic viscosity [η] of the acetone-soluble component was 0.47 dl / g, and the ethylene / propylene rubber content was 23%.

(2-2) Production Example 2; Polymer A-2 (ethylene / propylene rubbery polymer / styrene / acrylonitrile copolymer)
In the stainless steel autoclave used in Production Example 1, ethylene / propylene / dicyclopentadiene rubber (ethylene / propylene / dicyclopentadiene = 63/32/5 (%) as an ethylene / α-olefin rubbery polymer (A1). ) Mooney viscosity (ML _{1 + 4} , 100 ° C.) 33) 30 parts, vinyl monomer (A2) 49 parts styrene, 21 parts acrylonitrile, 0.5 parts tert-dodecyl mercaptan, 140 parts toluene The internal temperature was raised to 75 ° C., and the autoclave contents were stirred for 1 hour to obtain a uniform solution. After sufficiently substituting the inside of the autoclave with nitrogen, 0.45 part of tert-butylperoxyisopropyl monocarbonate was added and the internal temperature was further raised to 100 ° C. The polymerization reaction was carried out at a stirring speed of 100 rpm. From 4 hours after the start of the polymerization reaction, the internal temperature was raised to 120 ° C., and the reaction was further continued for 2 hours while maintaining this temperature to complete the polymerization reaction. Thereafter, the internal temperature was cooled to 100 ° C., 0.2 part of octadecyl-3- (3,5-tert-butyl-4-hydroxyphenol) -propionate was added, and then the reaction mixture was extracted from the autoclave. Polymer A-2 pellets were obtained in the same manner as above. The graft ratio of this polymer A-2 was 60%, the intrinsic viscosity [η] of the acetone-soluble component was 0.45 dl / g, and the ethylene / propylene / dicyclopentadiene rubber content was 32%.

(2-3) Production Example 3; Ethylene / Propylene Rubber Polymer Latex 100 parts of the ethylene / propylene / dicyclopentadiene copolymer rubber used in Production Example 2 was dissolved in 566 parts of n-hexane, and then manufactured by Mitsui Chemicals. 10 parts of acid-modified polyethylene (high wax 2203A) was added, and 4.5 parts of oleic acid was further added and completely dissolved. Separately, 0.6 parts of ethylene glycol was added to an aqueous solution in which 0.9 parts of potassium hydroxide was dissolved in 700 parts of water, and the mixture was kept at 60 ° C., and the polymer solution prepared above was added little by little to emulsify. Stir with a mixer. Next, part of the solvent and water was distilled off to obtain a latex having a particle size of 400 to 600 nm. To this latex, 1.5 parts of divinylbenzene and 1.0 part of di-tert-butylperoxytrimethylcyclohexane are added to 100 parts of the rubber component and reacted at 120 ° C. for 1 hour to form an EPDM-containing crosslink. Latex was obtained.

(2-4) Production Example 3; Polymer A-3 (ethylene / propylene rubbery polymer / styrene / acrylonitrile copolymer)
After replacing the stainless steel autoclave used in Production Example 1 with nitrogen, 50 parts of EPDM latex (solid content) prepared in Production Example 3 as an ethylene / α-olefin rubber polymer (A1) in a nitrogen stream, An aqueous solution consisting of 170 parts of water, 0.01 parts of sodium hydroxide, 0.2 parts of sodium pyrophosphate, 0.01 parts of ferrous sulfate heptahydrate and 0.2 parts of glucose was charged. A polymerization temperature of 80 ° C. and a constant temperature, 3 parts of a vinyl monomer (A2) comprising 9 parts of acrylonitrile, 21 parts of styrene and 0.05 part of tert-dodecyl mercaptan and 0.1 part of cumene hydroperoxide Polymerization was performed while continuously adding over time, and then polymerization was continued for 1 hour while maintaining the polymerization temperature to obtain a latex of polymer A-3. The polymer conversion rate of the obtained latex was 98%. To this latex, 0.2 part of 2,2'-methylene-bis (4-ethyl-6-tert-butylphenol) was added to complete the polymerization. The reaction product latex was coagulated with an aqueous sulfuric acid solution, washed with water, and dried to obtain a polymer A-3. The graft ratio of this polymer A-3 was 63%, and the intrinsic viscosity [η] of the acetone-soluble component was 0.42 dl / g.

(3) Component (3-1) Production Example 4; Polymer B-1 (styrene / acrylonitrile copolymer)
Two stainless steel autoclaves having a ribbon wing with an internal volume of 30 liters were connected and purged with nitrogen, and then 70 parts of styrene, 30 parts of acrylonitrile and 20 parts of toluene were continuously added to the first reaction vessel. A solution of 0.12 part of tert-dodecyl mercaptan and 5 parts of toluene as a molecular weight regulator, and 0.1 part of 1,1′-azobis (cyclohexane-1-carbonitrile) and 5 parts of toluene as a polymerization initiator The solution was continuously fed. The polymerization temperature of the first group was controlled at 110 ° C., the average residence time was 2.0 hours, and the polymerization conversion was 57%. The obtained polymer solution was continuously taken out from the first reaction vessel by the same amount as the styrene, acrylonitrile, toluene, molecular weight regulator and polymerization initiator supplied by the pump provided in the second reaction vessel. The reaction vessel was fed. The polymerization temperature of the second reaction vessel was 130 ° C., and the polymerization conversion was 75%. The copolymer solution obtained in the second reaction vessel was directly devolatilized from the unreacted monomer and solvent using a twin-screw, three-stage vented extruder, and the intrinsic viscosity [η] 0.48 dl / g of polymer B-1 was obtained.

(4) (C) component The following were used as (C) component of this invention.
(4-1) Low molecular weight oxidized polyethylene C-1 Sunwax EP-250P (trade name) manufactured by Sanyo Chemical Industries
Acid value 20 mgKOH / g, average molecular weight 2000
(4-2) Ultra High Molecular Weight Polyethylene C-2 Miteron XM-221U (trade name) manufactured by Mitsui Chemicals, Inc.
Average molecular weight 2 million, average particle size 25 μm
(4-3) Polytetrafluoroethylene C-3 Daikin Industries, Ltd. Lubron L-5 (trade name)
Average particle diameter of about 7μm

(5) Component (5-1) Production Example 5; Polymer D-1 (Polybutadiene rubber polymer / styrene / acrylonitrile copolymer)
In a 7-liter glass flask equipped with a stirring blade, in a nitrogen stream, 95 parts of ion exchange water, 0.5 part of potassium rosinate, 0.1 part of tert-dodecyl mercaptan, conjugated diene rubber polymer ( D1) 30 parts (solid content) of polybutadiene latex (volume average particle size 200 nm, gel content 85%), 10 parts (solid content) of butadiene / styrene random polymer latex (volume average particle size 600 nm, styrene content 25%) ), 14.6 parts of styrene and 5.4 parts of acrylonitrile were added as a vinyl monomer (D2), and the temperature was raised while stirring. When the internal temperature reached 45 ° C., a solution in which 0.2 parts of sodium pyrophosphate, 0.01 parts of ferrous sulfate heptahydrate and 0.2 parts of glucose were dissolved in 20 parts of ion-exchanged water was added. . Thereafter, 0.07 part of cumene hydroperoxide was added to initiate polymerization. After polymerization for 1 hour, 50 parts of ion-exchanged water, 0.7 parts of potassium rosinate, 29.2 parts of styrene, 10.8 parts of acrylonitrile, 0.05 parts of tert-dodecyl mercaptan, and cumene hydroperoxide 0.01 The polymer conversion after 98 parts was continuously added over 3 hours and the polymerization was continued for 1 hour was 98%. Thereafter, 0.2 part of 2,2'-methylene-bis (4-methyl-6-tert-butylphenol) was added to complete the polymerization. The latex of polymer D-1 was coagulated with an aqueous sulfuric acid solution, washed with water, and then dried to obtain polymer D-1.
The graft ratio of this polymer D-1 was 68%, and the intrinsic viscosity [η] of the acetone soluble component was 0.45 dl / g.

Examples 1-17, Comparative Examples 1-5
Using the above components (A), (B), (C) and (D), each component was mixed with a Henschel mixer at the blending ratio shown in Table 1, and then a twin screw extruder with a vent (manufactured by Nippon Steel Works). , TEX44, barrel set temperature 240 ° C.) and kneaded to form pellets. After sufficiently drying the obtained pellet, a test piece was molded by the above method using this pellet, and evaluated by the above method using the obtained test piece. The evaluation results are shown in Table 1.
As is apparent from Table 1, the thermoplastic resin compositions of the present invention represented by Examples 1 to 17 are reduced in the squeaking noise targeted by the present invention, and further have impact resistance and molded article surface appearance. We provide molded products with a good balance.
In contrast, Comparative Example 1 is an example in which the amount of the component (A) used in the present invention is small outside the scope of the present invention, and the amount of the component (B) used is large outside the scope of the present invention. And the appearance of the molded product surface is inferior.
Comparative Example 2 is an example in which the amount of low molecular weight oxidized polyethylene used in the component (C) of the present invention is small outside the scope of the present invention, and itching sounds.
Comparative Example 3 is an example in which the amount of low molecular weight oxidized polyethylene in the component (C) of the present invention is large outside the scope of the present invention, but the pellets do not slip into the injection molding machine and can be molded. There wasn't.
Comparative Example 4 is an example in which the amount of ultrahigh molecular weight polyethylene used in the component (C) of the present invention is large outside the scope of the present invention. Impact resistance and appearance of molded product surface are inferior.
Comparative Example 5 is an example in which the amount of polytetrafluoroethylene used in the component (C) of the present invention is large outside the scope of the present invention, and the impact resistance and the surface appearance of the molded product are inferior.

  The automobile interior parts made of the specific thermoplastic resin composition of the present invention are remarkably reduced in the squeaking noise generated when the parts rub against each other, and the effect of reducing the squeaking noise is lowered even when left at a high temperature for a long time. In addition, it is possible to provide an automobile interior part that is maintained for a long time and is excellent in impact resistance and molded article surface appearance, and can be suitably used for an automobile ventilator or the like. In particular, it can be suitably used for a component having a fitting portion with another member.

Claims (6)

(A) A vinyl-based compound comprising an aromatic vinyl compound or an aromatic vinyl compound and another vinyl monomer copolymerizable with the aromatic vinyl compound in the presence of the ethylene / α-olefin-based rubbery polymer (A1). 5 to 100% by mass of a rubber-reinforced styrene resin obtained by polymerizing the monomer (A2),
(B) 0 to 95% by mass of the vinyl polymer, and a total of 100 parts by mass of the component (A) and the component (B),
(C) 0.1 to 30 parts by mass of at least one ethylene polymer selected from low molecular weight oxidized polyethylene (c1), ultrahigh molecular weight polyethylene (c2), and polytetrafluoroethylene (c3). An automotive interior part comprising a thermoplastic resin composition.   2. The interior of an automobile according to claim 1, wherein the amount of the ethylene / α-olefin rubber polymer (A1) is 3 to 40% by mass in 100% by mass of the total of the component (A) and the component (B). parts. Further, (D) a vinyl monomer comprising an aromatic vinyl compound or an aromatic vinyl compound and another vinyl monomer copolymerizable with the aromatic vinyl compound in the presence of the conjugated diene rubber polymer (D1). A graft polymer obtained by polymerizing the monomer (D2),
The mass ratio of the ethylene / α-olefin rubber polymer (A1) and the conjugated diene rubber polymer (D1) is blended in a range of (A1) :( D1) = 5 to 95: 95-5. The automobile interior part according to claim 1 or 2, characterized by the above-mentioned.   The automobile interior part according to any one of claims 1 to 3, wherein the acid value of the low molecular weight oxidized polyethylene (c1) is 10 to 30 (mgKOH / g).   The interior of an automobile according to any one of claims 1 to 4, wherein the ultrahigh molecular weight polyethylene (c2) has a molecular weight (measured by a solution viscosity method in accordance with ASTM D4020) of 400,000 to 2.5 million. parts.   The automobile interior part according to any one of claims 1 to 5, wherein the automobile interior part is used in an automobile ventilator.