JP3316164B2 - Thermoplastic resin composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermoplastic resin composition capable of improving sliding characteristics, friction and wear characteristics while maintaining high mechanical characteristics, and a molded product thereof.

[0002]

2. Description of the Related Art A crystalline thermoplastic polyester resin (for example, polyalkylene terephthalate resin) has excellent mechanical properties, electrical properties, and other physical and chemical properties, and has good processability. It is used as a plastic in a wide range of applications such as automobiles and electric / electronic parts. Such a crystalline thermoplastic polyester resin can be used alone for various molded articles, but depending on the field of use, various reinforcing agents and additives are added to improve its properties, especially mechanical properties. It is used for molding. In fields requiring high mechanical strength and rigidity, fibrous reinforcing agents such as glass fibers and carbon fibers are used. In order to provide high dimensional stability and flatness, styrene-
Butadiene-acrylonitrile copolymer (ABS resin)
Addition of an amorphous polymer such as such to a polyester resin has also been performed.

[0003] However, the required characteristics of such molded articles are becoming increasingly sophisticated, and as one example, further improvement in sliding characteristics is desired. Particularly, the composition containing the fiber reinforcing agent and the composition containing the amorphous polymer show excellent mechanical properties and dimensional stability, but when sliding with a metal or a resin, the self material and the mating material (the mating material is For resin)
All of them wear and generate squeak noise, which lowers the sliding characteristics. In particular, when an amorphous polymer such as an ABS resin is added to polyester, the resulting molded article has poorer abrasion with resin, greater wear of its own material, and abrasion powder as compared to a molded article of polyester alone. Scatter.

As a method of solving these problems, grease is conventionally applied to a sliding portion in many cases. However, the grease runs out over a long period of use, and the performance may deteriorate. For example, in a recording information medium that requires high accuracy (for example, a high-precision device such as a compact disk (CD) -read only memory (ROM)), grease adheres to the CD and a reading error may occur. Improving the slidability is an important issue. Conventionally, PTFE (polytetrafluoroethylene) has been used to improve the sliding characteristics.
There has been proposed a composition containing a sliding improver such as powder or graphite. In these compositions, although a slight improvement in the coefficient of friction is observed, the wear characteristics are not improved but tend to deteriorate. Further, in order to achieve a low coefficient of friction, a large amount of a sliding modifier must be added, and there is a problem that mechanical properties such as mechanical strength and toughness are reduced, and further improvement is desired.

Japanese Patent Application Laid-Open No. 4-76048 discloses that a graft copolymer such as polybutylene terephthalate or polyethylene terephthalate and an ABS resin is used to improve the friction and wear characteristics and to suppress the occurrence of sliding noise.
A sliding component formed of a resin composition containing an inorganic filler is disclosed. JP-A-7-150022 discloses that
A crystalline thermoplastic polyester resin, an olefin copolymer composed of an olefin polymer fragment and a vinyl polymer fragment, and a fatty acid ester obtained from a fatty acid having 12 or more carbon atoms, having good slidability. A polyester resin composition is disclosed. However, even with these resin compositions, it is sometimes difficult to significantly improve the friction and wear characteristics while maintaining the mechanical characteristics at a high level.

[0006]

Accordingly, an object of the present invention is to provide a thermoplastic resin composition having improved friction and wear characteristics while maintaining high mechanical properties, and a molded article using the same. is there. Another object of the present invention is to provide a thermoplastic resin composition and a molded product having a low coefficient of friction during continuous reciprocating sliding, capable of suppressing wear of the own material and the mating material, and having stable sliding characteristics. is there.

[0007]

Means for Solving the Problems The present inventors have conducted intensive studies to improve the slidability while maintaining high mechanical strength and high dimensional stability, and as a result, a polyester resin / amorphous polymer blend system was obtained. In addition, it was found that by adding a specific polyolefin-based copolymer and a specific branched ester in combination, the initial sliding torque can be improved, and the friction coefficient and wear characteristics can be significantly improved. Reached. That is, the thermoplastic resin composition of the present invention comprises (A) a thermoplastic polyester resin, and (B)
A rubber-modified styrenic resin, (C) an olefin copolymer composed of (c-1) an olefin polymer fragment and (c-2) at least one vinyl polymer fragment, and (D) at least one A branched ester obtained from a fatty acid having two branched chains and / or an alcohol having at least one branched chain. The thermoplastic resin composition may contain (E) an inorganic filler, (F) a flame retardant, (G) an inorganic flame retardant auxiliary, and the like. The thermoplastic resin composition is useful for obtaining molded articles such as sliding members.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the components constituting the resin composition of the present invention will be described in detail. [(A) Thermoplastic polyester resin] The thermoplastic polyester resin (A) can be obtained by polycondensation of a dicarboxylic acid component and a dihydroxy component, polycondensation of an oxycarboxylic acid component, or polycondensation of these three components. Any of a homopolyester and a copolyester may be used.

The dicarboxylic acid component includes, for example,
Terephthalic acid, isophthalic acid, phthalic acid, naphthalenedicarboxylic acid (such as 2,6-naphthalenedicarboxylic acid),
Diphenyl dicarboxylic acid, diphenyl ether dicarboxylic acid, diphenylmethane dicarboxylic acid, aromatic dicarboxylic acids or derivatives thereof such as diphenylethane dicarboxylic acid, alicyclic dicarboxylic acids or derivatives thereof such as cyclohexane dicarboxylic acid, adipic acid, azelaic acid, sebacic acid and the like Examples thereof include aliphatic dicarboxylic acids and derivatives thereof. The derivative may be a derivative capable of forming an ester, for example, a lower alkyl ester such as dimethyl ester, an acid anhydride, or an acid halide such as acid chloride. These dicarboxylic acid components can be used alone or in combination of two or more. Preferred dicarboxylic acid components are aromatic dicarboxylic acids such as terephthalic acid and naphthalenedicarboxylic acid.

The dihydroxy component constituting the polyester (A) includes, for example, aliphatic alkylene diols such as ethylene glycol, propylene glycol, 1,3-butanediol, 1,4-butanediol, neopentyl glycol and hexanediol; Alicyclic diols such as cyclohexanediol and cyclohexanedimethanol, hydroquinone, resorcinol, dihydroxyphenyl, naphthalene diol, dihydroxydiphenyl ether, 2,2-bis (4-hydroxyphenyl) propane (bisphenol A), and alkylene oxide for bisphenol A (C _2-4 alkylene oxide such as ethylene oxide and propylene oxide) adducts (diethoxylated bisphenol A, etc.)
Such as aromatic diols and polyoxyalkylene glycols (eg, polyoxyethylene glycol, polyoxypropylene glycol, polytetramethylene ether glycol, etc.). These dihydroxy components may be derivatives capable of forming an ester, for example, an alkyl group, an alkoxy group, or a halogen-substituted product. These dihydroxy components can be used alone or in combination of two or more. As preferred dihydroxy components, alkylene diols (particularly C _2-4 alkylene diols) and alicyclic diols are often used.

Examples of the oxycarboxylic acid include oxycarboxylic acids such as oxybenzoic acid, oxynaphthoic acid, and diphenyleneoxycarboxylic acid, and derivatives thereof. The derivatives include the above-mentioned dicarboxylic acid component and dihydroxy component. Corresponding derivatives are included. One or more of these compounds can be used. Further, in addition to the above components, a multifunctional monomer, for example, trimellitic acid, trimesic acid, a polycarboxylic acid such as pyromellitic acid, glycerin, trimethylolpropane, a small amount of a polyhydric alcohol such as pentaerythritol in combination. Is also good. Polyesters having a branched or crosslinked structure formed by using such a polyfunctional monomer can also be used.

The crystalline thermoplastic polyester produced by polycondensation using the above compound as a monomer component is used alone or in combination of two or more as a base resin in a thermoplastic resin composition. The polyester resin,
It may be non-crystalline, but is preferably crystalline.
Preferred polyester resins have at least 60 polyalkylene arylate units (eg, polyalkylene terephthalate units and polyalkylene naphthalate units).
It is composed of a crystalline polyester resin containing at least% by weight. That is, polyester resins include (i) polyalkylene terephthalate (polyethylene terephthalate, polybutylene terephthalate, etc.), polyalkylene naphthalate (polyethylene naphthalate, polybutylene naphthalate, etc.), (ii) polyalkylene terephthalate unit or polyalkylene naphthalate. 6 units
(Iii) polyalkylene terephthalate or polyalkylene naphthalate as a main component (for example, 60 to 98% by weight);
To 95% by weight). In particular, polybutylene terephthalate, or a copolyester having polybutylene terephthalate units (for example, a copolyester such as polyalkylene terephthalate or polyalkylene naphthalate having 60 to 98% by weight of polybutylene terephthalate units) or polybutylene terephthalate is included. Polyester-based resin compositions (for example, polyester-based resin compositions such as polyalkylene terephthalate compositions and polyalkylene naphthalate compositions containing 60 to 95% by weight of polybutylene terephthalate) are preferred.

[(B) Rubber-modified styrenic resin] The rubber-modified styrenic resin (B) contains at least an aromatic vinyl monomer (particularly an aromatic vinyl monomer and a vinyl cyanide monomer) in a rubber component. Is a graft copolymer obtained by graft polymerization, and is often an amorphous rubbery polymer.
As the rubber component, conjugated diene rubbers (polybutadiene, polyisoprene, butadiene-styrene copolymer,
Butadiene-acrylonitrile copolymer, ethylene-propylene-5-ethylidene-2-norbornene copolymer), ethylene-propylene rubber (EPDM rubber),
Examples thereof include acrylic rubber, ethylene-vinyl acetate copolymer, and halogenated polyolefin such as chlorinated polyethylene, and may be a hydrogenated product. These rubber components can be used alone or in combination of two or more. As a preferable rubber component, a conjugated diene rubber is often used. In the rubber component such as a conjugated diene rubber,
The gel content is not limited at all. The rubber component can be produced by a method such as emulsion polymerization, solution polymerization, suspension polymerization, or bulk polymerization.

Examples of the aromatic vinyl monomer include styrene, α-methylstyrene, methylstyrene, t-butylstyrene, dimethylstyrene (vinyltoluene),
Chlorostyrene, dichlorostyrene, bromostyrene,
Dibromostyrene and the like. These aromatic vinyl monomers can be used alone or in combination of two or more. Preferred aromatic vinyl monomers include styrene and α-
Methyl styrene and the like.

As the vinyl cyanide monomer, for example,
Examples include acrylonitrile and methacrylonitrile. These vinyl cyanide monomers can be used alone or in combination of two or more. The preferred vinyl cyanide monomer is acrylonitrile.

The aromatic vinyl monomer and vinyl cyanide monomer may be used in combination with other copolymerizable monomers.
Examples of the copolymerizable monomer include, for example, (meth) acrylates [eg, methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate,
(Meth) acrylic acid C such as t-butyl (meth) acrylate, hexyl (meth) acrylate, octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate
Hydroxyl group-containing (meth) acrylates such as _1-18 alkyl ester, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, glycidyl (meth) acrylate, etc., and carboxyl group-containing monomer [ For example, unsaturated monocarboxylic acids such as (meth) acrylic acid and crotonic acid, aliphatic unsaturated dicarboxylic acids such as maleic anhydride, maleic acid, fumaric acid, and itaconic acid, and maleic acid monoesters (monomethyl maleate, maleic acid Monoethyl _C1-10 alkyl esters of maleic acid such as monoethyl, monobutyl maleate and mono-2-ethylhexyl maleate) and unsaturated dicarboxylic acid monoesters such as fumaric acid monoester corresponding thereto, and maleimide monomers [ For example, maleimide, N-
Methylmaleimide, N-phenylmaleimide, etc.]. These copolymerizable monomers can be used alone or in combination of two or more. Preferred copolymerizable monomers include (meth) acrylic acid esters (especially methyl methacrylate), maleimide monomers (especially N-phenylmaleimide), (meth) acrylic acid, maleic anhydride and the like.

The ratio of the aromatic vinyl monomer, vinyl cyanide monomer and copolymerizable monomer is at least aromatic vinyl monomer (particularly, aromatic vinyl monomer and vinyl cyanide monomer). ) Is not particularly limited, for example,
Aromatic vinyl monomer / vinyl cyanide monomer = 10/9
0 to 90/10 (% by weight), preferably 20/80 to 8
0/20 (% by weight), especially about 30/70 to 70/30 (% by weight). The ratio of the aromatic vinyl monomer and the copolymerizable monomer is, for example, aromatic vinyl monomer / copolymerizable monomer = 10/90 to 100/0 (% by weight), In particular, it is about 30/70 to 70/30 (% by weight).

The ratio between the rubber component and the monomer in the graft polymer is not particularly limited, but the ratio of the rubber component / monomer = 10
/ 90-75 / 25 (% by weight), preferably 10/90
５０50/50 (% by weight), especially 10 / 90-40 / 60
(% By weight). 10% by weight of rubber component
If the amount is less than 70%, the impact resistance of the resin composition is reduced. If the amount exceeds 75% by weight, a flow mark or the like is easily formed on the molded product, not only the appearance is easily deteriorated, but also the affinity with the component (A) is easily reduced. . These rubber-modified styrenic resins (graft polymers) (B) can be used alone or in combination of two or more. As preferred graft polymers, for example, styrene-acrylonitrile-butadiene copolymer (ABS resin), styrene-acrylonitrile-ethylene copolymer, styrene-based block copolymer (for example,
Styrene-butadiene-styrene (SBS) copolymer,
Styrene-isoprene-styrene (SIS) copolymer,
Styrene-ethylene-butylene-styrene copolymer), styrene-acrylonitrile-ethylene-propylene-ethylidene norbornene copolymer (AES), and hydrogenated products thereof. Particularly preferred graft polymers include styrene-acrylonitrile-butadiene copolymer (ABS resin), styrene-acrylonitrile-ethylene-propylene-ethylidene norbornene copolymer (AES) and hydrogenated products thereof.

The ratio between the thermoplastic polyester resin (A) and the rubbery polymer (B) can be selected in a wide range, for example, (A) / (B) = 95/5 to 30/70% by weight. And preferably about 90/10 to 40/60% by weight.

[(C) Olefin copolymer] A feature of the present invention is that the slidability improver composed of the (C) olefin copolymer and (D) the branched ester is used in the aforementioned (A) The point is that it is added to the polyester resin composition composed of the component and the component (B). (C) The olefin-based copolymer is
A graft or block copolymer in which (c-1) an olefin polymer and (c-2) at least one vinyl polymer are chemically bonded in a branched or crosslinked structure. The main chain portion of the component (C) is often composed of (c-1) an olefin polymer, and the (c-1) olefin polymer includes polyethylene (low-density polyethylene, ultra-low-density polyethylene, wire, etc.). Low-density polyethylene, medium-density polyethylene, high-density polyethylene, etc.), homopolymers of poly-α-olefins such as polypropylene and polybutene, hydrogenated polybutadiene, and copolymers containing these as main components. Examples of the copolymer include ethylene-propylene copolymer, ethylene-1-butene copolymer, and ethylene-ethyl acrylate copolymer.
(Meth) acrylic acid ester copolymers, ethylene- (meth) acrylic acid copolymers, ethylene-vinyl acetate copolymers and the like can be mentioned. Among these olefin polymers, polyethylene, polypropylene and ethylene-propylene copolymer are preferred.

The vinyl polymer (c-2) includes various vinyl monomers such as acrylic monomers (such as (meth) acrylic acid ester and (meth) acrylonitrile) and vinyl ester monomer. (Vinyl acetate, vinyl propionate, etc.), and styrene-based monomers (styrene, α-methylstyrene, etc.) and at least one monomer selected from homo- or copolymers. Preferred monomers include at least one selected from acrylic monomers and styrene monomers. Vinyl polymer (c-
As 2), for example, acrylic polymer (for example,
Polymethyl methacrylate, polyethyl methacrylate, polybutyl methacrylate, polymethyl acrylate, polyethyl acrylate, polybutyl acrylate, poly (2-ethylhexyl) acrylate, methyl methacrylate-ethyl acrylate copolymer, methacryl (Meth) acrylic acid C _1-18 alkyl ester homo- or copolymer such as methyl acrylate-butyl acrylate copolymer), aromatic vinyl polymer (such as polystyrene), polyacrylonitrile, acrylonitrile-aromatic vinyl copolymer (E.g., acrylonitrile-styrene copolymer), (meth) acrylate-styrene copolymer (e.g., methyl methacrylate-styrene copolymer, ethyl acrylate-styrene copolymer, butyl acrylate-styrene) Copolymers). . Preferred vinyl polymers (c-
2) includes poly (meth) acrylate (for example,
Polymethyl methacrylate) and styrene-containing polymers (eg, acrylonitrile-styrene copolymer, polystyrene, etc.).

The characteristic feature of the graft or block copolymer (C) is that the (c-1) olefin polymer and the (c-2) vinyl polymer having different properties are chemically bonded at at least one point. , A graft or block copolymer having a branched or cross-linked structure, and having a graft or block structure allows the (c-1) olefin polymer or (c-2) vinyl polymer to be used alone. A remarkable effect that cannot be obtained by blending is obtained.

The method for preparing the graft or block copolymer having (c-1) an olefin polymer segment and (c-2) a vinyl polymer segment is not particularly limited.
For example, it can be easily prepared using a conventional radical reaction. For example, a method in which a radical catalyst is added to (c-1) an olefin polymer and (c-2) a vinyl polymer and melt-kneaded,
A free radical is generated by a radical catalyst (such as a peroxide) on one of the (c-1) olefin polymer and the (c-2) vinyl polymer, and the polymer component having the free radical is replaced with another polymer component. It can be prepared by a method of melt-kneading with the polymer component.

The ratio of the (c-1) olefin polymer and the (c-2) vinyl polymer constituting the graft or block copolymer (C) is, for example, (c-1) / (c- 2) = 95/5
４０40/60 (% by weight), preferably = 90 / 10-4
It is about 0/60 (% by weight). When the ratio of the (c-1) olefin polymer exceeds 95% by weight, compatibility and affinity with the polyester resin are reduced, separation is remarkable, and peeling and abrasion characteristics are easily reduced, If the amount is less than 40% by weight, the effect of modifying the polyester resin is reduced, and the coefficient of friction is not significantly improved. In addition, the said graft or block copolymer (C) can also be obtained from the market, for example, it is marketed by Nippon Oil & Fats Co., Ltd. as trade names "Modiper A1400", "A1200", "A1100" etc. ing.

The amount of the graft or block copolymer (C) used is, for example, based on 100 parts by weight of the total amount of the polyester resin (A) and the rubber-modified styrene resin (B).
0.1 to 40 parts by weight (for example, 1 to 40 parts by weight), preferably 1.5 to 30 parts by weight, more preferably 2 to 20 parts by weight
It is about parts by weight. If the proportion of the component (C) is too small, the sliding characteristics are not so much improved. If the proportion is too large, surface peeling occurs and the appearance of the molded article is deteriorated.

[(D) Branched ester] The branched ester (D) is a fatty acid ester derived from an alcohol and / or a fatty acid having at least one branched chain. Examples of the branched fatty acid constituting the branched ester include:
Representative examples include isoacids and anteisoic acids, but not limited thereto, and any branched fatty acid can be used as a component of the ester. As the branched fatty acid, a higher fatty acid, for example, having 16 or more carbon atoms (for example,
6-30, preferably about 16-22) saturated or unsaturated fatty acids, and specifically, isopalmitic acid,
Examples include isostearic acid and isobehenic acid. Preferred branched fatty acids include saturated higher fatty acids. As the alcohol having a branched chain, a higher alcohol, for example, a saturated or unsaturated alcohol having 16 or more carbon atoms (for example, about 16 to 30 carbon atoms, preferably about 16 to 22 carbon atoms) is preferable, and specifically, isotridecyl alcohol , Hexyldecyl alcohol, octyldodecyl alcohol,
Isostearyl alcohol and the like. Preferred branched alcohols include saturated higher alcohols.

Examples of the alcohol which forms a branched ester in combination with the above-mentioned fatty acid having a branched chain include the above-mentioned alcohol having a branched chain, myristyl alcohol,
Straight chain aliphatic alcohols such as cetyl alcohol, stearyl alcohol and behenyl alcohol (preferably straight chain saturated higher alcohols having about 14 to 30 carbon atoms, particularly straight chain saturated higher alcohols having about 14 to 22 carbon atoms), ethylene glycol, diethylene glycol, Polyhydric alcohols such as triethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, tetramethylene glycol, neopentyl glycol, glycerin, diglycerin, trimethylolpropane, pentaerythritol, dipentaerythritol, and sorbitan Can be illustrated. These alcohols can be used alone or in combination of two or more.

The fatty acid constituting the branched ester in combination with the above-mentioned alcohol having a branched chain includes, in addition to the fatty acid having a branched chain, myristic acid, palmitic acid, stearic acid, behenic acid, serotinic acid, montanic acid, and the like. Linear fatty acids (preferably having 14 to 30 carbon atoms)
Linear saturated higher fatty acids, particularly linear saturated higher fatty acids having about 14 to 22 carbon atoms), citric acid, succinic acid, adipic acid, azelaic acid, sebacic acid and other aliphatic polycarboxylic acids, phthalic acid, and anhydride. Examples include aromatic polycarboxylic acids such as phthalic acid, isophthalic acid, terephthalic acid, trimellitic acid, and pyromellitic acid. These fatty acids can be used alone or in combination of two or more.

Furthermore, from the viewpoints of workability such as long-term sliding stability, extrudability, moldability, etc., branched esters include:
(1) an ester derived from a branched saturated fatty acid, (2) an ester derived from a branched saturated alcohol, (3) an ester derived from a branched saturated fatty acid and a branched saturated alcohol, and (4) an ester derived from a branched saturated fatty acid. Esters derived from a dihydric alcohol [(preferably dodecyl stearic acid or isostearic acid and ethylene glycol, polyethylene glycol, propylene glycol,
Esters with one or more polyhydric alcohols selected from the group consisting of glycerin, trimethylolpropane and pentaerythritol, particularly partial esters (unreacted OH in the molecule)
Esters having one or more groups)] are preferred. Although high sliding properties are imparted by blending the branched ester oil, the branched ester is preferably an ester oil having a melting point of less than 40 ° C, particularly a liquid ester oil having a melting point of 25 ° C or less. The amount of the branched ester (D) used is, for example, a resin composition composed of the component (A) and the component (B), that is, a total amount of the component (A) and the component (B) of 100.
0.1 to 15 parts by weight (for example, 0.1 to 15 parts by weight)
To 10 parts by weight), preferably 0.5 to 10 parts by weight, and more preferably about 1 to 10 parts by weight. If the amount of the branched ester (D) is less than 0.1 part by weight, the effect of improving the sliding properties is not sufficient, and if it exceeds 15 parts by weight, the wear characteristics and the surface appearance are impaired. The ratio of the olefin-based copolymer (C) and the branched ester (D) is not particularly limited.
Component (D) / component (C) = 1 to 30% by weight, preferably 5 to 25% by weight. By blending both component (C) and component (D) in combination with component (A) and component (B), the resulting polyester composition has high dimensional stability and excellent friction and wear. Has characteristics. Particularly, as a chassis component which is an electric / electronic set component, it exhibits a very excellent effect on friction and wear with respect to a resin or a metal material such as a tray material, a bearing material and a gear / cam material. Even if one of the components (C) and (D) is added alone to the components (A) and (B), a certain effect is exhibited, but a sufficient effect is exhibited. Requires a large amount of addition. Therefore, problems such as a decrease in strength, a deterioration in surface state, and a decrease in moldability are likely to occur. In addition, when the ester (especially ester oil) is blended, not only the sliding property cannot be maintained for a long time but also the ease of oozing,
The ester oil itself volatilizes and scatters in a high temperature environment during extrusion molding and molding, and cannot be used effectively. In the present invention, the above-mentioned problem is solved by combining the olefin-based copolymer (C) and the branched ester (D) in combination at the same time. Further, by using the olefin-based copolymer (C), a polyester resin composition having high abrasion characteristics without exfoliation of the polyolefin component by the branched ester (D) and a decrease in abrasion can be obtained.

By adding (E) an inorganic filler such as glass fiber to such a polyester resin composition,
It is possible to obtain a polyester resin composition having excellent friction and wear properties and high strength and heat resistance. Further, by blending a flame retardant as the component (F) and a flame retardant auxiliary as the component (G), a polyester resin composition having not only excellent slidability but also excellent flame retardancy can be obtained.

[(E) Inorganic filler] The (E) inorganic filler is useful for obtaining a molded article excellent in performance such as mechanical strength, rigidity and heat resistance, and electrical properties. As the inorganic filler (E), various forms, for example, fibrous, granular, and plate-like fillers can be used depending on the purpose. To obtain high mechanical strength and rigidity, fibrous fillers are used. Agents are preferred.
Examples of the fibrous filler include glass fiber, asbestos fiber, carbon fiber, silica fiber, silica / alumina fiber, zirconia fiber, potassium titanate fiber, boron nitride fiber, and metal fiber (stainless steel, aluminum, titanium, copper, Inorganic fibers such as metal fibrous materials such as brass). Typical fibrous fillers are glass fibers or carbon fibers. Note that high melting point organic fibers (for example, an aliphatic or aromatic polyamide, an aromatic polyester, a fluororesin, an acrylic resin such as polyacrylonitrile, and the like) can also be used.

As the particulate filler, for example, silica,
Quartz powder, glass beads, glass powder, milled glass fiber, calcium silicate, aluminum silicate, kaolin, talc, clay, diatomaceous earth, silicates such as wollastonite, iron oxide, titanium oxide, zinc oxide, alumina And various metal powders such as metal carbonates such as calcium carbonate and magnesium carbonate, metal sulfates such as calcium sulfate and barium sulfate, and silicon carbide. Examples of the plate-like filler include mica, glass flake, various metal foils, and the like. Among them, as the non-fibrous inorganic filler, glass flake, mica powder, talc, glass beads, milled glass fiber and the like are preferable.

These fillers (E) can be used alone or in combination of two or more. The combined use of a fibrous filler, particularly a glass fiber, and a powdery and / or plate-like filler is a preferable combination particularly for obtaining a molded article having both mechanical strength, dimensional accuracy, and electrical properties.

In using these fillers (E), if necessary, a sizing agent or a surface treating agent such as an epoxy compound, an acrylic compound, an isocyanate compound, a silane compound or a titanate compound may be used. It is desirable to use compounds. The filler may be subjected to surface treatment or convergence treatment with these compounds in advance, and used.
You may add simultaneously at the time of material preparation.

The amount of the filler (E) to be used is not particularly limited, but if it is added in an extremely large amount, the filler floats on the surface of the molded article, and the abrasion is deteriorated. The amount of the filler (E) used is, for example, 10% in total of the components (A) and (B).
0 to 100 parts by weight (for example, 10 to 10 parts by weight)
100 parts by weight), preferably 10 to 80 parts by weight, more preferably about 10 to 50 parts by weight.

[(F) Flame Retardant] As the flame retardant (F), any compound generally used as a flame retardant for thermoplastic polyester resins can be used as long as it does not reduce friction and wear properties. Preferred flame retardants (F) include organic halogen compounds, for example, halogenated phenyl, halogenated diphenyl ether, halogenated aromatic bisimide compound, halogenated aromatic epoxy compound, low molecular weight organic halogen compound of bisphenol A, halogenated polycarbonate, halogenated polycarbonate Polystyrene and the like. Halogen in the organic halogen compound is fluorine, chlorine, bromine,
It can be any of iodine, but is generally bromine.
Such flame retardants can be used alone or in combination of two or more.

The content of the flame retardant (F) component is, for example,
It is about 0.5 to 25 parts by weight, preferably about 1 to 20 parts by weight (for example, 2 to 20 parts by weight) based on 100 parts by weight of the total amount of the components (A) and (B). Excessive addition of flame retardant, in addition to mechanical, physical properties, thermal stability, etc.,
The appearance of the resin molded article is easily impaired, and when it is too small, it is difficult to improve the flame retardancy.

[(G) Inorganic Flame Retardant Aid] As the (G) inorganic flame retardant aid, it is generally used as an inorganic flame retardant aid for thermoplastic polyesters as long as the intended friction and wear properties are not reduced. Any known compounds can be used. Preferred (G) inorganic flame retardant aids include, for example, antimony trioxide, antimony tetroxide, antimony pentoxide, antimony halide, sodium antimonate, aluminum hydroxide, magnesium hydroxide, tin dioxide, zirconium oxide, and metaborough. Examples include zinc oxyacid, barium borate, and molybdenum oxide. These (G) inorganic flame retardant aids can be used alone or in combination of two or more.

The content of the inorganic flame retardant aid (G) is, for example, 0.1 to 20 parts by weight, preferably 1 to 100 parts by weight based on 100 parts by weight of the total of the components (A) and (B). -10
It is about parts by weight. If the amount of the inorganic flame retardant aid (G) is less than 0.1 part by weight, the flame retardancy of the composition is not so much improved, and if it exceeds 20 parts by weight, the strength of the composition tends to decrease. Note that, depending on the use of the molded product, there may be a case where “V-0” in the flame retardant category of UL Standard 94 is required. In that case, it is preferable to use asbestos, a fluororesin (for example, polytetrafluoroethylene) or the like in combination with the flame retardant.

The composition of the present invention may contain, if necessary, various additives (for example, stabilizers such as antioxidants, ultraviolet absorbers and light stabilizers, antistatic agents, lubricants, coloring agents such as dyes and pigments). Agents, lubricants, plasticizers, etc.). In particular, due to the addition of antioxidants, the molded articles obtained show higher thermal stability, in particular long-term thermal stability and mechanical properties.

As antioxidants, hindered phenol compounds, amine compounds, thioether compounds and the like can be used. As the hindered phenol compound, for example,
1,6-hexanediol bis [3- (3,5-di-t
-Butyl-4-hydroxyphenyl) propionate], pentaerythritol tetrakis [3- (3,5
-Di-t-butyl-4-hydroxyphenyl) propionate], triethylene glycol bis [3- (3-t
-Butyl-5-methyl-4-hydroxyphenyl) propionate]. Examples of the amine compound include N-phenyl-N'-isopropyl-p-
Phenylenediamine, N, N'-diphenyl-p-phenylenediamine, 4,4-bis- (4-α, α-dimethylbenzyl) diphenylamine, a condensation reaction product of diphenylamine and acetone, N-phenylnaphthylamine,
N, N'-di-β-naphthylphenylenediamine and the like can be exemplified. As the thioether compound, for example,
Dilauryl thiodipropionate, dimyristyl thiodipropionate, distearyl thiodipropionate,
Lauryl stearyl thiodipropionate, tetrakis [methylene-3- (dodecylthio) propionate] methane, and dialkyl (C ₁₂ -C _{18)-3,3-thiodipropionate} and the like. Preferred antioxidants include hindered phenol compounds, for example, pentaerythritol tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], triethylene glycol bis [3- (3- t-butyl-5-
Methyl-4-hydroxyphenyl) propionate]. In order to improve the feed stability of the raw material components in a molding process such as extrusion molding, it is advantageous to add a lubricant (lubricant).

The composition of the present invention can be prepared by a conventional mixing method (eg, dry mixing, melt extrusion such as melt extrusion or melt kneading). The composition may be in the form of a powder, granules, pellets or flakes. The molded article of the present invention can be obtained by a conventional method (eg, extrusion molding, injection molding, etc.).
Easily prepared. For example, after mixing each component, 1
A method in which pellets are prepared by kneading and extruding with a twin-screw or twin-screw extruder, and molding is performed using the pellets. Either a method of obtaining a molded article having a composition ratio or a method of directly charging one or more of each component to a molding machine may be used. Further, it is preferable to add a part of the resin component as a fine powder mixed with other components, since these components can be uniformly blended.

Since the composition of the present invention has excellent mechanical properties and slidability, it can be used for audiovisual (AV) /
Office automation (OA) equipment [video tape recorder, video camera, video disc player, compact disc (CD) player, CD-R
In order to obtain molded parts (eg, mechanical parts requiring high dimensional stability and slidability such as levers, gears, bearings, and chassis) of word processors, personal computers, copiers, printers, and the like equipped with OM, it is extremely important. Useful. Further, the polyester resin composition containing an inorganic filler and / or a flame retardant has excellent flame retardancy, high mechanical properties, heat resistance, and excellent slidability. Molded parts required (eg faster CD
-Very useful for computer built-in chassis parts such as ROM and DVD).

[0044]

The resin composition of the present invention is composed of a polyester / graft copolymer blend composition containing a specific polyolefin copolymer and a specific branched ester oil. While maintaining the characteristics
Friction and abrasion can be greatly improved. In addition, a molded product having high dimensional stability, a low coefficient of friction during continuous reciprocating sliding, suppressing abrasion of the own material and the mating material, and obtaining a stable sliding characteristic can be obtained.

[0045]

EXAMPLES The present invention will be described below in more detail with reference to examples, but the present invention is not limited to these examples. Examples 1-22 Component (A) [Polybutylene terephthalate resin (PB
T) or an acid-modified polybutylene terephthalate (acid-modified PBT) in which 12 mol% of a terephthalic acid component is substituted with isophthalic acid], a component (B) (ABS resin or AES resin), and an olefin copolymer (C) shown below. Ingredient, (D)
A branched ester component, optionally (E) an inorganic filler,
(F) The flame retardant and (G) the flame retardant auxiliary were mixed in the proportions shown in the table, and then melt-kneaded with a twin-screw extruder to prepare a pellet-shaped composition. Next, a test piece was prepared by injection molding using the pellet, and the characteristics of the test piece were evaluated. The results are shown in the table.

Comparative Examples 1 to 21 As shown in the table, for comparison with the examples, a composition in which at least one of the components (C) and (D) was not added, and the composition was replaced with the component (C) Example 1 shows a composition using polyethylene, a composition using a lubricant (PTFE) as the component (D '), a composition using a fatty acid ester other than the component (D) in combination with the component (B), and the like. The characteristics of the test pieces prepared in the same manner as in Example 1 were evaluated. The results are shown in the table.

The component (C) and its constituent components (c-
The contents of 1) and (c-2) are as follows, and these components are indicated by abbreviations in the table. (C) Component (the numerical value in parentheses indicates% by weight) PE-g-PMMA: PE (50) and PMMA (50)
Graft copolymer with PE-g-AN / S: PE (50) and AN / S (50)
PP-g-PS: graft copolymer of PE (50) and PS (50) PP-g-AN / S: PP (70) and AN / S (30)
(C-1) component PE: Low density polyethylene PP: polypropylene (c-2) component PMMA: polymethyl methacrylate AN / S: acrylonitrile-styrene copolymer PS: polystyrene The evaluation method is as follows. (1) Surface condition of molded article Test specimen (100 mm x 15 mm) under the following molding conditions
× 3 mm), and the surface peeling state was evaluated according to the following five levels.

[Molding conditions] Molding machine: IS80 manufactured by Toshiba Corp. Cylinder temperature (° C): nozzle part 255 ° C, head part 2
50 ° C., center 240 ° C., hopper lower 230 ° C. Injection pressure 75 MPa Injection speed 1.2 m / min Mold temperature 70 ° C. [Evaluation criteria] 5: No surface peeling 4: Surface has very slight peeling 3: Surface 2: A considerable part of the surface peels. 1: The surface peels significantly over the entire surface. (2) Sliding characteristics Using a simple reciprocating sliding tester, perform a friction and wear test under the following conditions. The dynamic friction coefficient and the specific wear amount were measured. "Test conditions" Load = 4N, Speed V = 5cm / sec, Stroke L =
5cm, number of slides 30000 times "test method" moving test piece (plate material, thickness about 3m
m) A pin material (φ10 mm) is brought into contact with the longitudinal end face (end face width: about 3 mm), and a load is applied from the pin material in the width direction of the test piece to reciprocate the test piece in a predetermined stroke in the longitudinal direction. Then, the above test was performed. AB as pin material
S resin (manufactured by Daicel Chemical Industries, Ltd., trade name: Sebian), A
BS resin / polycarbonate (PC) resin (manufactured by Daicel Chemical Industries, Ltd., trade name Novalloy S) or steel (S55C)
It was used.

(3) Flexural modulus The flexural modulus was measured according to ASTM D-790. (4) Flammability test (UL-94) Subject 9 of Underriders Laboratories
5 (UL94) according to the method of 5 (thickness: 0.
8 mm) was used to test the flame retardancy and dripping characteristics of the resin during combustion, and the combustion level was determined.

[0050]

[Table 1]

[0051]

[Table 2]

[0052]

[Table 3]

[0053]

[Table 4]

[0054]

[Table 5]

[0055]

[Table 6]

Continuation of the front page (51) Int.Cl. ⁷ identification code FI C08L 51/06 C08L 51/06 53/00 53/00 55/02 55/02 (58) Investigated field (Int.Cl. ⁷ , DB name ) C08L 51/04-51/06 C08L 53/00 C08L 55/02 C08L 67/00-67/04

Claims (17)

(57) [Claims] (A) a thermoplastic polyester resin,
(B) a rubber-modified styrenic resin, (C) an olefin copolymer composed of (c-1) an olefin polymer fragment and (c-2) at least one vinyl polymer fragment, and (D) A) a thermoplastic resin composition comprising a fatty acid having at least one branched chain and / or a branched ester obtained from an alcohol having at least one branched chain. 2. The thermoplastic resin composition according to claim 1, wherein (A) the thermoplastic polyester resin is composed of a crystalline polyester resin containing at least 60% by weight or more of a polyalkylene arylate unit. 3. The thermosetting polyester resin according to claim 1, wherein (A) the thermoplastic polyester resin is a crystalline polyester resin containing at least 60% by weight or more of a polyalkylene terephthalate unit or a polyalkylene naphthalate unit. Plastic resin composition. 4. The method according to claim 1, wherein (A) the thermoplastic polyester resin is
The thermoplastic resin according to any one of claims 1 to 3, which is a polybutylene terephthalate, a copolymer containing 60% by weight or more of a polybutylene terephthalate unit, or a polyester resin composition containing polybutylene terephthalate as a main component. Resin composition. 5. The rubber-modified styrenic resin (B) is a polymer obtained by graft-polymerizing at least an aromatic vinyl monomer and a vinyl cyanide monomer onto a rubber component.
5. The thermoplastic resin composition according to any one of Items 4 to 4. 6. The (C) olefin-based copolymer comprises (c-1)
Polyethylene, polypropylene and at least one olefin polymer fragment selected from ethylene-propylene copolymer and (c-2) an acrylic monomer,
A graft or block copolymer comprising a homo- or copolymer fragment of at least one monomer selected from styrene-based monomers, according to claim 1. Thermoplastic resin composition. 7. The thermoplastic resin composition according to claim 1, wherein (D) the fatty acid and / or alcohol constituting the branched ester has 16 to 30 carbon atoms. 8. The thermoplastic resin composition according to claim 1, wherein (D) the branched ester is an ester oil of a higher fatty acid having at least one branched chain and a polyhydric alcohol. . 9. (A) a thermoplastic polyester resin 30 to
With respect to 100 parts by weight of a resin composition composed of 95% by weight and (B) 70 to 5% by weight of a rubber-modified styrenic resin,
The thermoplastic resin composition according to any one of claims 1 to 8, comprising (C) 0.5 to 40 parts by weight of an olefin-based copolymer, and (D) 0.1 to 15 parts by weight of a branched ester. . 10. The thermoplastic resin composition according to claim 1, further comprising (E) an inorganic filler. 11. The thermoplastic resin composition according to claim 10, wherein (E) the inorganic filler is a fibrous inorganic filler or a plate-like inorganic filler. 12. The thermoplastic resin composition according to claim 10, wherein (E) the inorganic filler is at least one selected from glass fibers, glass flakes, mica and talc. 13. The composition according to claim 10, wherein the proportion of the inorganic filler (E) is 10 to 100 parts by weight based on 100 parts by weight of the resin composition composed of the components (A) and (B). Thermoplastic resin composition. 14. The thermoplastic resin composition according to claim 1, further comprising (F) a flame retardant and (G) an inorganic flame retardant aid. 15. A flame retardant of (F) 0.5 per 100 parts by weight of a resin composition composed of the components (A) and (B).
To 35 parts by weight and (G) an inorganic flame-retardant aid 0.1 to 20
15. The thermoplastic resin composition according to claim 14, comprising parts by weight. 16. A molded article formed from the thermoplastic resin composition according to claim 1. Description: 17. The molded article is a sliding member.
The molded article as described.