JPH10130458A - Polyacetal resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a resin compsn. excellent in sliding characteristics by melt mixing and kneading a polyacetal resin with a modified olefin polymer, an inorg. filler, and if desired a specific lubricant. SOLUTION: This compsn. is prepd. by melt mixing and kneading 100 pts.wt. polyacetal resin with 0.5-100 pts.wt. modified olefin polymer obtd. by modifying an olefin polymer with at least one compd. selected from among unsatd. carboxylic acids and their anhydrides and derives. (e.g. maleic anhydride) and 0.1-20 pts.wt. inorg. filler, pref. at least one filler selected from among calcium carbonate, potassium titanate, barium carbonate, and zinc oxide. A lubricant used is selected from among a silicone, and α-olefin oligomer, paraffin, a substd. diphenyl ether, a 10C or higher fatty acid deriv., and a 10C or higher aliph. alcohol deriv.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a polyacetal resin obtained by blending a specific olefin polymer, an inorganic filler, and, if desired, a lubricant, followed by melt-kneading.
The present invention relates to a polyacetal resin composition having improved compatibility, dispersibility, and interfacial adhesion between resins, and having excellent friction and wear characteristics.

[0002]

BACKGROUND OF THE INVENTION Polyacetal resins have well-balanced mechanical properties,
It is widely used in the fields of automobiles, electric and electronic products, etc. because of its excellent friction and wear resistance, chemical resistance, heat resistance, electric properties, and the like. However, the required characteristics in such a field are gradually becoming more sophisticated, and as one example, further improvement in sliding characteristics as well as general physical properties is desired. Such sliding characteristics are friction and wear characteristics with the inorganic filler compounding material.
As an example, chassis such as CD-ROMs are increasingly required for cost reduction and weight reduction.
/ ABS, PBT / ABS and other resins, glass fiber,
In many cases, an inorganic filler compounding material in which an inorganic filler such as glass flake, talc, and mica is mixed is used. Conventionally, gear parts and lever parts often slide against a metal boss caulked on a sheet metal chassis, and the friction and wear characteristics of the metal material counterpart were important,
When members such as bosses are integrally formed with the chassis using such a resin material, the importance of slidability with resin bosses and resin guides has increased. In sliding with such a material for a resin chassis, a conventional metal material is difficult to slide due to the poor friction and wear characteristics of the mating material such as ABS resin and the influence of the surface roughness of the compounded inorganic filler. Therefore, even better friction and wear characteristics than those required for sliding were required, and improvements were required. In general, for the purpose of improving sliding characteristics, addition of fluororesin or polyolefin resin to polyacetal resin, fatty acid, fatty acid ester, silicone oil,
Lubricating oils such as various mineral oils have been added. The addition of fluororesin or polyolefin resin improves the sliding properties to some extent, but such different resins have poor compatibility with polyacetal resins, so the sliding properties under high surface pressure are insufficient, and inorganic fillers The abrasion resistance is poor in sliding with compounded materials. In addition, there is also a problem in moldability that peeling is easily generated on the surface of the molded product and precipitates are easily generated in a molding die. In addition, the addition of lubricating oil has various difficulties such as difficulty during extrusion or molding, or bleeding during use, and when used in combination with the above-mentioned different resin, the compatibility between the different resin and the polyacetal is reduced. However, there is a problem in that the material impairs the wear resistance significantly, and a material having improved these properties has been desired for such a problem.

[0003]

Means for Solving the Problems As a result of intensive studies to achieve the above object, the present inventor has found that a specific polyolefin polymer and an inorganic filler and, if desired, a specific lubricant are blended with the polyacetal resin. It has been found that a resin composition having excellent sliding properties can be obtained by melt-kneading, and the present invention has been accomplished. That is, the present invention provides (A)
With respect to 100 parts by weight of the polyacetal resin, (B) the olefin polymer (B-1) is obtained by adding at least one selected from the group consisting of unsaturated carboxylic acids and their anhydrides and their derivatives (B-2). Modified modified olefin polymer 0.5 to 100
The present invention provides a polyacetal resin composition obtained by mixing and melt-kneading 0.1 to 20 parts by weight of (C) an inorganic filler.

[0004]

BEST MODE FOR CARRYING OUT THE INVENTION The components of the present invention will be described below. The polyacetal resin (A) used in the present invention, and a polymer compound having an oxymethylene group (-CH ₂ O-) as the main constituent unit, a polyoxymethylene homopolymer or an oxymethylene group as the main repeating units, Other structural units such as ethylene oxide, 1,3-
Any of copolymers, terpolymers and block polymers containing a small amount of units derived from comonomers such as dioxolane and 1,4-butanediol may be used, and the molecules may have not only linear but also branched or crosslinked structures. It may be a known modified polyoxymethylene into which another organic group is introduced. The degree of polymerization is not particularly limited as long as it has melt moldability. Preferred polyacetal resins have a melt index (ASTMD-1238-89E, hereinafter abbreviated as MI) of 1 to 50 g / 1.
0 minutes, and more preferably, the MI is 7 to 30 g / 1.
It's 0 minutes.

[0005] Next, the component (B) blended into the polyacetal resin in the present invention comprises an olefin polymer (B-1) and an unsaturated carboxylic acid and its acid anhydride and their derivatives (B-2).
And a modified olefin polymer modified with at least one member selected from the group consisting of: As the olefin polymer (B-1) used here, ethylene, propylene,
-Homopolymers of α-olefins such as -butene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene, 1-dodecene, and copolymers of two or more of these, and And an α, β-unsaturated acid such as acrylic acid or methacrylic acid or methyl acrylate, ethyl acrylate, propyl acrylate,
Α, β-unsaturated carboxylic esters such as butyl acrylate, 2-ethylhexyl acrylate, hydroxyethyl acrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, 2-ethylhexyl methacrylate, hydroxyethyl methacrylate , 1,4-hexadiene, dicyclopentadiene, 5-
Non-conjugated dienes such as ethylidene-2-norbornene and 2,5-norbonadiene; conjugated diene components such as butadiene, isoprene and piperylene; aromatic vinyl compounds such as α-methylstyrene; vinyl ethers such as vinyl methyl ether; Random, block or graft copolymers comprising at least one of the comonomer components such as compound derivatives, and the like.
It does not matter whether or not there are side chains or branches, the degree of copolymerization, and the like. More specific examples of the olefin polymer (B-1) of the present invention include high-pressure polyethylene, medium-low pressure polyethylene, vapor-phase ethylene-α-olefin copolymer, LL
DPE, polypropylene, polybutene, ethylene-propylene copolymer, ethylene-methyl acrylate copolymer, ethylene-ethyl acrylate copolymer, ethylene-
There are butyl acrylate copolymer, ethylene-methyl methacrylate copolymer, ethylene-ethyl methacrylate copolymer, ethylene-propylene-diene terpolymer and the like. Preferably, polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-methyl acrylate copolymer, ethylene-ethyl acrylate copolymer, ethylene-methyl methacrylate copolymer, ethylene-ethyl methacrylate copolymer is there. The (B) modified olefin-based copolymer used in the present invention is obtained by converting the above-mentioned olefin-based polymer (B-1) to an unsaturated carboxylic acid, an acid anhydride thereof, and a derivative thereof (B-2). Modified with at least one selected from the group. Used here
(B-2) means acrylic acid, methacrylic acid, maleic acid,
Unsaturated carboxylic acids such as citraconic acid, itaconic acid, tetrahydrophthalic acid, nadic acid, methylnadic acid, allylsuccinic acid, and maleic anhydride, citraconic anhydride, itaconic anhydride, tetrahydrophthalic anhydride, nadic anhydride, methyl anhydride Unsaturated carboxylic anhydrides such as nadic acid and allyl succinic anhydride; and derivatives thereof. As a modification method, one or more compounds selected from the group consisting of a polyolefin (co) polymer, an unsaturated carboxylic acid, an acid anhydride thereof, and a derivative thereof are prepared by adding an appropriate compound in a solution state or a molten state. A method of heating and reacting with a radical initiator such as an organic peroxide is suitable, but not particularly limited thereto. The compounding amount of both components is suitably from 0.1 to 20 parts by weight, preferably from 0.1 to 10 parts by weight, based on 100 parts by weight of the olefin polymer. If the amount of the effective compound in the modified olefin polymer is too small, the affinity between (A) the polyacetal resin and (B) the modified olefin polymer is not sufficiently improved, so that the effect of the present invention is not improved. If it is not obtained, or if it is too large, physical properties such as sliding characteristics to be improved may be reduced. Specific examples of preferred modified olefin copolymers include polyethylene, polypropylene, ethylene-propylene copolymer, ethylene ethyl acrylate copolymer, ethylene methyl acrylate copolymer, ethylene methacrylic acid modified with maleic anhydride. Ethyl copolymer, ethylene methyl methacrylate copolymer and the like can be mentioned. Further, in the present invention, α modified with maleic anhydride
A combination of a modified olefin polymer mainly composed of olefin, a modified polymer composed of an α-olefin modified with maleic anhydride and an α, β-unsaturated carboxylic acid ester, for example, maleic anhydride-modified polyethylene and / or anhydride By using a maleic acid-modified polypropylene and a maleic anhydride-modified ethylene methyl methacrylate copolymer and / or a maleic anhydride-modified ethylene ethyl acrylate copolymer in combination, it exerts even better friction and wear properties, and is more preferable. Can be used. Preferred modified olefin copolymers have an MI of 0.01 to 100 g / 10 min, more preferably have an MI of 0.1 to 50 g / 10 min, and particularly preferably have a MI of 0.2 to 30 g. / 10 minutes. The blending ratio of (A) polyacetal resin and (B) modified olefin polymer is (A) polyacetal resin 1
(B) modified olefin polymer 0.5 to 100 parts by weight
100 parts by weight, preferably 0.5 to 50 parts by weight, particularly preferably 0.5 to 20 parts by weight. If the amount of the component (B) is too small, the physical properties to be improved such as sliding properties are insufficient. If the amount is too large, the mechanical properties are deteriorated and the appearance of the molded product is deteriorated.

Next, the inorganic filler used as the component (C) in the present invention will be described. As the inorganic filler (C) in the present invention, calcium carbonate, potassium titanate,
At least one selected from barium carbonate, talc, wollastonite, mica, zinc oxide and the like are preferably used, and more preferably at least one selected from calcium carbonate, potassium titanate, barium carbonate and zinc oxide. . The inorganic filler (C) does not depend on the shape such as the particle shape, fiber shape, and aspect ratio, and any inorganic filler listed in this group can be used. The amount of the inorganic filler (C) is 0.1 to 20 parts by weight based on 100 parts by weight of the component (A).
It is preferably from 0.3 to 15 parts by weight, particularly preferably from 0.5 to 10 parts by weight. If the amount of the component (C) is too small, the effect of improving the sliding property against metal cannot be sufficiently obtained, and if the amount is too large, the sliding property against resin is deteriorated.

As described above, the composition of the present invention comprises (A) a polyacetal resin, (B) a modified olefin polymer, and
(C) Inorganic filler alone has good properties, especially sliding properties, has a remarkable effect on moldability, etc.,
Further effects can be obtained by using a lubricant (D) in addition to the components (A) to (C). In the present invention, the lubricant (D) is selected from the group consisting of silicone, α-olefin oligomer, paraffin, substituted diphenyl ether, a derivative of a fatty acid having 10 or more carbon atoms, and a derivative of an aliphatic alcohol having 10 or more carbon atoms. At least one is preferably used. Any of such specific lubricants can be suitably used, and among such lubricants,
A lubricant having a specific viscosity, average molecular weight, and / or substituent is more preferably used. Hereinafter, such a lubricating oil will be described in detail. As the silicone, polydimethylsiloxane and polymethylphenylsiloxane represented by the structure (1) are preferably used.

[0008]

Embedded image

(Where R is a methyl group, a part of which is an alkyl group, a phenyl group, a halogenated alkyl group,
It may be a halogenated phenyl group, polyalkylene glycol, or the like. ) A part of methyl groups of dimethyl siloxane, halogenated phenyl group represented by chlorophenyl group, C ₈ or more alkyl groups, alkylene glycols represented by polyethylene glycol, derivatives of C ₈ or more aliphatic carboxylic acids It is also possible to use modified polyorganosiloxanes substituted by various substituents such as higher aliphatic ester groups and halogenated alkyl groups represented by trifluoromethyl groups. In the present invention, such a silicone oil having a kinematic viscosity (25 ° C.) in the range of 100,000 to 100,000 cSt is preferably used.

The α-olefin oligomer is mainly composed of C ₆ to
Alone α- olefins to C ₂₀ or ethylene and C _3,
It is an aliphatic hydrocarbon having a structure obtained by copolymerizing an α-olefin having a carbon number of ~ ₂₀ . In the present invention, the number average molecular weight is
400-4000 ethylene / α-olefin cooligomers are preferably used.

Paraffin refers to a so-called paraffinic mineral oil obtained mainly by refining a petroleum fraction. In the present invention, those having an average molecular weight of 300 to 800 are preferably used.

[0012] substituted diphenylether, as shown by the following (2), the phenyl ether, C ₁₂ or higher saturated aliphatic chain, an alkyl group, an ester group, in the form of substituents selected from ether group, at least 1 Shows compounds that have been introduced in more than one species. There is no specific molecular weight.
Any alkyl-substituted diphenyl ether is preferably used.

[0013]

Embedded image

(R is an alkyl group, an ether group, or an ester group introduced at part or all of the 2-6 position and the 2′-6 ′ position) As the substituent of such an alkyl-substituted diphenyl ether, a dodecyl group, Examples include a linear alkyl group such as a tetradecyl group, a hexadecyl group, and an octadecyl group, and a branched alkyl group represented by (3).

[0015]

Embedded image

Examples of the ester group include a dodecyloxycarbonyl group, a tetradecyloxycarbonyl group, a hexadecyloxycarbonyl group, an octadecyloxycarbonyl group, a lauroyloxy group, a myristoyloxy group, a palmitoloxy group, and a stearoyloxy group. And the like. Examples of the ether group include a lauroyl group, a myristoyl group, a palmitoyl group, and a stearoyl group. Furthermore, derivatives such as isosuaryl alcohol and isostearic acid, in which the ester or ether group aliphatic hydrocarbon chain has a branched structure, may be used. The effect of such a substituted diphenyl ether is not limited at all in the position of the substituent, and any substituted diphenyl ether is preferably used. However, from the viewpoint of synthesis, preferably the 2,4,6,2 ′, 4 ′, 6 ′ position is used. Is a substituted diphenyl ether having a substituent on any or all of
Particularly preferred is a disubstituted compound at the 4,4'-position.

The derivatives of fatty acids having 10 or more carbon atoms in the present invention include esters of fatty acids having 10 or more carbon atoms with mono- or polyvalent aliphatic and / or aromatic alcohols having 10 or more carbon atoms, or Amides of 10 or more fatty acids with primary, secondary or tertiary amines are included. As the derivative of the aliphatic alcohol having 10 or more carbon atoms, an ester of an aliphatic alcohol having 10 or more carbon atoms and a monovalent or polyvalent aliphatic and / or aromatic carboxylic acid having 10 or more carbon atoms may be mentioned. . The details of such esters and amides are described below. Fatty acids having 10 or more carbon atoms constituting such esters include lauric acid, tridecanoic acid, myristic acid,
Saturated fatty acids such as palmitic acid, stearic acid, isostearic acid, oleic acid, linoleic acid, linoleic acid, arachidic acid, behenic acid, lignoceric acid, cetyronic acid, montanic acid and melicic acid, unsaturated fatty acids, linear fatty acids,
Branched fatty acids, and 2-bromostearic acid;
Derivatives of such fatty acids such as 18-bromostearic acid and 18-hydroxystearic acid are preferably used. Examples of the alcohol constituting the fatty acid and the ester include n-octyl alcohol, 2-ethylhexyl alcohol, isononyl alcohol, n-decyl alcohol, isodecyl alcohol, lauryl alcohol, myristyl alcohol, cetyl alcohol, and 14-methylhexadecane-1-. All, stearyl alcohol, oleyl alcohol, 16-methylhexadecanol, 18-methylnonadecanol, 18-methyleicosanol, docosanol, 20-methylhenicosanol, 20-methyldocosanol, tetracosanol, tetra Monohydric saturated and unsaturated aliphatic alcohols such as cosanol, hexacosanol, octacosanol and the like, straight-chain and branched alcohols, etc., are preferably used. Examples of the aromatic alcohol constituting the ester include phenol, catechol, and naphthol. Also,
As the aliphatic polyhydric alcohol, ethylene glycol,
Propylene glycol, 1,4-butanediol, 1,5-
Pentanediol, 1,6-hexanediol, 1,2-octanediol, hexadecane-1,2-diol, octadecane-1,2-diol, icosan-1,2-diol, glycerin, trimethylolpropane, erythritol, penta Polyhydric alcohols such as erythritol, sorbitol, 1,2-cyclononanediol, 1,2-cyclodecanediol and dipentaerythritol, tripentaerythritol, diethylene glycol, diglycerol, triglycerol, polyglycerol, polyethylene glycol, polypropylene Examples thereof include condensates of such polyhydric alcohols such as glycol, and partial esters of such polyhydric alcohols with polybasic acids such as succinic acid and adipic acid, all of which are preferably used. First grade,
Examples of the secondary or tertiary amine include ammonia, ethylenediamine, tetramethylenediamine, monoethaninolamine, and the like. As aliphatic alcohols having 10 or more carbon atoms, lauryl alcohol, myristyl alcohol, cetyl alcohol, 14-methylhexadecane-1-
Oar, stearyl alcohol, oleyl alcohol,
16-methylhexadecanol, 18-methylnonadecanol, 18-methylicosanol, docosanol, 20-methylhenicosanol, 20-methyldocosanol, tetracosanol, tetracosanol, hexacosanol, octacosanol And the like, and saturated and unsaturated aliphatic alcohols, straight-chain and branched alcohols, etc., all of which are preferably used. Examples of the fatty acids constituting such alcohols and esters include the above fatty acids, lauric difference, tridecanoic acid, myristic acid, palmitic acid, stearic acid, isostearic acid, oleic acid, linoleic acid, linoleic acid, arachidic acid, behenic acid, lignoceric acid,
Saturated fatty acids such as cetironic acid, montanic acid, and melicic acid;
Unsaturated fatty acids, straight-chain fatty acids, and branched fatty acids, and 2-bromostearic acid, 18-bromostearic acid,
Derivatives of such fatty acids such as 12-hydroxystearic acid are all preferably used. Examples of the aromatic carboxylic acid include benzoic acid and phthalic acid. As the aliphatic polybasic acids, oxalic acid, malonic acid, succinic acid,
Glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, 1,12-dodecamethylenedicarboxylic acid, 1,14-tetradecamethylenedicarboxylic acid, 1,16
-Hexadecamethylene dicarboxylic acid, 1,18-octadecamethylene dicarboxylic acid, trimellitic acid, maleic acid,
Examples thereof include aliphatic polybasic acids such as fumaric acid and derivatives of such carboxylic acids, all of which are preferably used. Ester composed of carboxylic acid and alcohol and amide composed of carboxylic acid and amine are all preferably used, but the following esters and amides are more preferably used from the viewpoint of availability. That is, lauryl laurate, lauryl stearate, cetyl palmitate,
Isotridecyl stearate, oleyl oleate, stearyl stearate, isostearyl stearate, isostearyl isostearate, behenyl behenate,
Ethylene glycol distearate, glycerin monostearate, glycerin monobehenate, glycerin di, tristearate, trimethylolpropane triisostearate, pentaerythritol tetraisostearate, pentaerythritol tetrastearate,
Esters such as polyethylene glycol dilaurate, polyethylene glycol distearate, diisotridecyl adipate, diisotridecyl phthalate, amides such as palmitic amide, stearic acid amide, ethylene bisstearic acid amide, tetramethylene bisstearic acid amide, and the like. One or more of such esters and amides are preferably used.

In the present invention, the amount of the lubricant (D) added is 0.1 to 20 parts by weight, preferably 0.5 to 5 parts by weight, based on 100 parts by weight of the total of the components (A), (B) and (C). Department.
If the amount is less than 0.1 part by weight, the original effect of the lubricant is hardly exhibited,
Conversely, if the amount is more than 20 parts by weight, the properties of the base polyacetal will be impaired, which is not preferable.

The composition of the present invention can be further added with various known stabilizers to reinforce the stability. Further, in order to improve the physical properties according to the intended use, various known additives may be further compounded. If you give an example of an additive,
Examples include various colorants, release agents (other than the above-mentioned lubricants), nucleating agents, antistatic agents, other surfactants, and heterogeneous polymers (other than the above-mentioned graft copolymers). In addition, as long as the performance of the object composition of the present invention is not significantly reduced, fibrous, powdery or granular fillers such as inorganic / organic / metallic fillers may be used alone or in combination of two or more. You can also.

Next, the composition of the present invention is easily prepared by a known method generally used as a conventional method for preparing a resin composition. For example, after mixing each component, kneading and extruding with a single-screw or twin-screw extruder to prepare pellets, once preparing pellets (master batch) having different compositions, and mixing (diluting) the pellets in a predetermined amount (dilution) Any method can be used. Further, in the preparation of such a composition, pulverizing part or all of each component, mixing this with other components, and performing extrusion or the like is a preferable method for improving the dispersibility of the additive. is there. Also, lubricant
(D) In particular, when a liquid material is used, a method in which a lubricant is previously mixed with each component, impregnated, kneaded, and then extruded also facilitates the preparation of the composition, and improves workability and This is a preferred method from the viewpoint of improving slidability.

A sliding member obtained by processing such a composition by a method such as molding and / or extrusion is excellent in friction / wear characteristics, not only sliding against metal but also sliding against resin, and is suitable for the fields of AV and OA. It is suitably used for various sliding parts.

[0022]

EXAMPLES The present invention will be described in more detail with reference to the following Examples, but it should not be construed that the invention is limited thereto. Examples 1 to 22, Comparative Examples 1 to 13 As shown in Tables 1 and 2, (A) polyacetal resin and (B)
Modified olefin polymer, (C) inorganic filler, depending on the case
(D) After mixing various lubricants at the ratios shown in Tables 1 and 2,
Using a twin-screw extruder, the mixture was melt-kneaded at a set temperature of 190 ° C. at a screw rotation speed of 80 rpm and pelletized. Next, the pellets were molded by an injection molding machine to prepare test pieces, which were evaluated. The results are shown in Tables 1 and 2. The methods for evaluating various physical properties in the examples are as follows. [Appearance of molded article] Test piece for evaluation (50 mm x 50 mm x 1 mmt; φ
(A 0.7 mm center pin gate method), and the state of peeling of the surface was evaluated according to the following five grades.

Peeling of molded article 1 Peeling of whole molded article 2 Peeling around gate of molded article 3 Small peeling at gate of molded article 4 No peeling of molded article itself. There is a jetting mark around the gate. 5 No peeling Molding machine EPN80 made by Toshiba Cylinder temperature (℃) = 200-200-180-160 Mold temperature (℃) = 85 Injection speed (m / min) = 3.0 Primary Pressure (MPa) = 90 Secondary pressure (MPa) = 60 Molding cycle (s) = 20 "-10" [Friction and wear test] <Slidability against GF-ABS> Using Suzuki type friction and wear tester, Sliding with GF-ABS (Sebian, manufactured by Daicel Chemical Industries, Ltd.) was performed, and the dynamic friction coefficient and the specific wear amount were measured. Sliding condition testing machine Suzuki type friction and wear tester (Orientec Co., Ltd.) Surface pressure 0.06MPa Linear velocity 15cm / sec 24 hours sliding <Slidability against steel> Using a Suzuki type friction and wear tester, S
55C), and the dynamic friction coefficient and the specific wear amount were measured. Sliding condition tester Suzuki type friction and wear tester (manufactured by Orientec Co., Ltd.) Surface pressure 0.98MPa Linear velocity 15cm / sec Sliding for 24 hours

[0024]

[Table 1]

[0025]

[Table 2]

A-1: Polyoxymethylene copolymer (M
(I = 27 g / 10 min) B-1: 2% maleic anhydride-modified polyethylene B-2: 1% maleic anhydride-modified polyethylene B-3: 1% maleic anhydride-modified polypropylene B-4: 1% maleic anhydride-modified Ethylene-ethyl acrylate copolymer C-1: Calcium carbonate (heavy calcium carbonate, average particle size
4.3 μm) C-2: Calcium carbonate (colloidal calcium carbonate, average particle size
0.2 μm) C-3: Potassium titanate C-4: Barium carbonate D-1: Polydimethylsiloxane (average molecular weight 18,000, viscosity 1000 cSt) D-2: Polydimethylsiloxane (average molecular weight 65,000, viscosity 60000 cSt) D-3: α-olein oligomer (average molecular weight 1030, viscosity
800cSt) D-4: α-olein oligomer (average molecular weight 2600, viscosity
D-5: Paraffin (average molecular weight 750, viscosity 1000 cSt) D-6: Alkyl-substituted diphenyl ether (average molecular weight 33
8, viscosity 200 cSt) D-7: isostearyl stearate (average molecular weight 536,
Solid) D-8: Stearyl stearate (average molecular weight 536, solid)

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI C08L 23:26 83:04 23:00) (C08K 13/02 3:26 3:22 5:01 5:06 5:09 5 : 05)

Claims (16)

[Claims] (1) An olefin polymer (B-1) is synthesized from an unsaturated carboxylic acid, an acid anhydride and a derivative thereof (B-2) with respect to 100 parts by weight of a polyacetal resin (A). A polyacetal resin composition comprising a mixture of 0.5 to 100 parts by weight of a modified olefin polymer modified with at least one selected from the group consisting of 0.1 to 20 parts by weight of an inorganic filler (C) and melt-kneading. 2. The polyacetal resin composition according to claim 1, wherein (C) the inorganic filler is at least one selected from calcium carbonate, potassium titanate, barium carbonate and zinc oxide. 3. The modified olefin polymer of the component (B) is composed of 100 parts by weight of the olefin polymer (B-1) and maleic anhydride (B-1).
-2) The polyacetal resin composition according to claim 1 or 2, which is modified at 0.1 to 20 parts by weight. 4. The polyacetal resin composition according to claim 3, wherein the olefin polymer (B-1) is an olefin (co) polymer mainly composed of α-olefin. 5. The polyacetal resin composition according to claim 3, wherein the olefin polymer (B-1) is an olefin copolymer of an α-olefin and an α, β-unsaturated carboxylic acid ester compound. 6. The α, β- component constituting the olefin copolymer.
The unsaturated carboxylic acid ester compound is methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, methyl methacrylate, ethyl methacrylate,
The polyacetal resin composition according to claim 5, which is at least one member selected from the group consisting of propyl methacrylate and butyl methacrylate. 7. The olefin polymer (B-1) is an olefin (co) polymer selected from the group consisting of polyethylene, polypropylene and ethylene-propylene copolymer, and / or ethylene-methyl acrylate. A polymer, an ethylene-ethyl acrylate copolymer, an ethylene-methyl methacrylate copolymer, or an olefin copolymer selected from the group consisting of ethylene-ethyl methacrylate copolymers. Item 4. The polyacetal resin composition according to Item 3. 8. The polyacetal resin composition according to claim 1, further comprising 0.1 to 20 parts by weight of a lubricant (D) based on 100 parts by weight of the total of the components (A), (B) and (C). Stuff. (D) The lubricant is silicone, α-olefin oligomer, paraffin, substituted diphenyl ether,
The polyacetal resin composition according to claim 8, wherein the polyacetal resin composition is at least one selected from the group consisting of derivatives of fatty acids having 10 or more carbon atoms and derivatives of aliphatic alcohols having 10 or more carbon atoms. (D) The silicone of the lubricant has a kinematic viscosity (25%).
The polyacetal resin composition according to claim 9, which is polydimethylsiloxane or polymethylphenylsiloxane having a temperature range of 100 to 100,000 cSt. 11. The polyacetal resin composition according to claim 9, wherein (D) the α-olefin oligomer of the lubricant is an α-olefin oligomer having an average molecular weight of 400 to 4000 and / or an ethylene / α-olefin cooligomer. (D) The paraffin of the lubricant has an average molecular weight of
The polyacetal resin composition according to claim 9, which is 300 to 800 paraffins. (D) The substituted diphenyl ether of the lubricant is a compound wherein at least one kind of a saturated aliphatic substituent selected from an alkyl group having 12 or more carbon atoms, an ester group and an ether group is introduced into the phenyl group. The polyacetal resin composition according to claim 9. (D) The lubricant is a derivative of a fatty acid having 10 or more carbon atoms, which is an ester of a fatty acid having 10 or more carbon atoms and a monovalent or polyvalent aliphatic and / or aromatic alcohol having 10 or more carbon atoms. The polyacetal resin composition according to claim 9, which is an amide of a fatty acid having 10 or more carbon atoms and a primary, secondary or tertiary amine. (D) A derivative of the aliphatic alcohol having 10 or more carbon atoms of the lubricant is a mixture of an aliphatic alcohol having 10 or more carbon atoms and a monovalent or polyvalent aliphatic and / or aromatic compound having 10 or more carbon atoms. The polyacetal resin composition according to claim 9, which is an ester with a carboxylic acid. 16. A sliding member comprising the polyacetal resin composition according to claim 1.