JP2003192871A - Polyacetal resin composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polyacetal resin composition having balanced mechanical properties, excellent sliding property and weld characteristics, and also having excellent extrusion processability and moldability. <P>SOLUTION: This polyacetal resin composition is obtained by compounding 0.1-5 pts.wt. of (D) a polyfunctional carbodiimide compound and/or (E) a polyfunctional epoxy compound with 100 pts.wt. of (I) a polyacetal resin composition having 50-99 wt.% content of (A) a polyacetal resin. The polyacetal composition (I) comprises (A) the polyacetal resin, (B) a polyether-ester-amide resin and/or (C) a modified polymer of a vinyl compound, modified by at least one kind of a reactive functional group selected from the group consisting of an acid anhydride, an epoxy group and a carboxy group. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a polyacetal resin composition excellent in impact resistance, slidability and moldability. More specifically, the present invention relates to a polyacetal resin composition having well-balanced mechanical properties and excellent sliding properties, and having good extrusion processability and moldability.

[0002]

2. Description of the Related Art Polyacetal resins have been in the spotlight in recent years as engineering plastics having well-balanced mechanical properties, good self-lubricating properties and electrical properties, and are widely used in various mechanical parts and electric parts. . However, its impact resistance is not always sufficient as compared with other engineering plastics such as polyamide resin and polycarbonate resin, and therefore its application to fields requiring high impact resistance is limited. Further, due to the recent high performance of mechanical products, electric products, etc., it is required for polyacetal resin to have further improved sliding properties and wear resistance properties.

In order to improve the impact resistance of polyacetal resin, a method of adding various rubbers and elastomers to the polyacetal resin has been tried. For example, it is possible to add a nitrile group-containing rubber in JP-B-45-12674, an ethylene-based copolymer in JP-B-45-26231, and an elastic rubber graft copolymer in JP-B-48-34830. Each of them has been proposed, but such rubbers generally have a problem of compatibility with the polyacetal resin, and therefore it has been difficult to compound a practically sufficient amount with the polyacetal resin. Further, although the use of polyester elastomers and polyether ester amides, which are considered to have relatively good compatibility with polyacetal resins, has been investigated, the improvement of impact resistance was insufficient. In Japanese Patent Laid-Open No. 61-69859 and Japanese Patent Laid-Open No. 08-325430, a phenoxy resin is added as a compatibilizing agent to improve the compatibility between the polyacetal resin and the polyetheresteramide resin to improve the impact resistance. Although a method for improving has been proposed, its improving effect is not sufficient, and further improvement has been desired.

On the other hand, it has been attempted to add a vinyl compound polymer represented by polyolefin to the polyacetal resin in order to improve impact resistance, specific gravity, abrasion resistance / friction characteristics and low temperature brittleness of the polyacetal resin. As with the polyacetal resin, the vinyl compound polymer has poor compatibility, so if the vinyl compound polymer is added in an amount necessary for exhibiting the improvement effect, the die head is melted and kneaded by a twin-screw extruder or the like. Further, there are problems that the ejected strands are immediately cut and cannot be pelletized well, and that the injection-molded product has a problem such as surface peeling. In order to improve such problems,
As a vinyl compound polymer, it has been attempted to add a modified vinyl compound polymer such as an acid anhydride-modified polyolefin or an epoxy-modified polyolefin, but generally, the improvement effect is small, such as decomposition of the polyacetal resin and increase of mold deposit. Since a new defect occurs, further improvement has been desired.

Further, the biggest drawback of a material obtained by blending a polyacetal resin and a different resin represented by a vinyl compound polymer is that the physical properties of the weld portion caused by the association of molten resins flowing from different directions during injection molding. This is a large decrease, and there is a restriction in shape when designing a product or a die.

[0006]

DISCLOSURE OF THE INVENTION The present invention overcomes various drawbacks of such a blend material of a polyacetal resin and a polyether ester amide resin or a vinyl compound polymer, and has impact resistance, slidability and molding. An object is to provide a polyacetal resin composition having excellent properties.

[0007]

Means for Solving the Problems As a result of intensive studies, the present inventors have found that when a polyacetal resin is kneaded with a polyetheresteramide resin and / or a modified vinyl compound polymer, a polycarbodiimide compound and / or The inventors have found that the compatibility is remarkably improved and various physical properties are remarkably improved by adding a polyvalent epoxy compound, and the present invention has been accomplished. That is, the gist of the present invention is to provide at least one reactive functional group selected from the group consisting of (A) polyacetal resin, (B) polyether ester amide resin and / or (C) acid anhydride group, epoxy group and carboxyl group. Consisting of a modified vinyl compound polymer modified with a group,
0.1 to 5 parts by weight of (D) polyvalent carbodiimide compound and / or (E) polyvalent epoxy compound per 100 parts by weight of polyacetal resin composition (I) having a content of (A) of 50 to 99% by weight. It exists in the polyacetal resin composition formed by mixing the same.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The resin composition of the present invention will be described in detail below. The (A) polyacetal resin used in the present invention is a formaldehyde monomer or its trimer (trioxane) or tetramer (tetraoxane).
An oxymethylene homopolymer consisting essentially of an oxymethylene unit produced from a cyclic oligomer such as, and the above raw materials and ethylene oxide, propylene oxide, epichlorohydrin, 1,3-dioxolane, glycol formal, and diglycol. An oxymethylene copolymer containing 0.1 to 20% by weight of an oxyalkylene unit having 2 to 8 carbon atoms in a polyoxymethylene main chain produced from a cyclic ether such as formal is included. Among these polyacetal resins, preferred are polyoxymethylene copolymers having oxyethylene units produced from trioxane and ethylene oxide or 1,3-dioxolane, and more preferably 2 to 7.5 oxyethylene units. It is a polyoxymethylene copolymer containing wt%.

The (B) polyetheresteramide resin used in the present invention is (A) a polyamide unit of 15 to 90.
Wt% and (b) polyoxyalkylene glycol unit 8
It is mainly composed of 5 to 10% by weight and has a molecular weight of 5,
000-50,000, preferably 10,000-4
It is a segmented copolymer in the range of 10,000.
The (a) polyamide unit constituting the polyether ester amide resin is a polymer having an amide bond,
It may be any of (1) lactam ring-opening polycondensate, (2) aminocarboxylic acid polycondensate, and (3) dicarboxylic acid and diamine polycondensate.

Examples of the lactam (1) include caprolactam, enanthlactam, laurolactam, and undecanolactam. As the aminocarboxylic acid of (2), ω-aminocaproic acid, ω-aminoenanthic acid,
ω-aminocaprylic acid, ω-aminopentonic acid, ω-aminocapric acid, 11-aminoundecanoic acid, 12-aminododecanoic acid and the like can be mentioned. Examples of the dicarboxylic acid (3) include adipic acid, azelaic acid, sebacic acid, undecanedioic acid, dodecanedioic acid, isophthalic acid, and polymerized fatty acids. The diamines include hexamethylenediamine, heptamethylenediamine, octamethylenediamine. , Decamethylenediamine, metaxylylenediamine and the like. The molecular weight of such a polyamide unit is 300 to 15,000, preferably 800 to 5,000.
Is. Incidentally, two or more kinds of those exemplified as the amide unit-forming monomer may be used in combination. Preferred as the polyamide unit is a dimer acid polyamide obtained mainly by a polycondensation reaction of polymerized fatty acid and diamine.
The polymerized fatty acid is a polymer of unsaturated fatty acid or a polymer obtained by hydrogenating such a polymer to reduce the degree of unsaturation. As the polymerized fatty acid used in the present invention, for example, 1
Dimer of monobasic fatty acid (dimer acid) having 0 to 24 carbon atoms and having at least one double bond or triple bond.
And / or hydrogenates thereof are preferred. Examples of the dimer acid include dimers such as oleic acid, linoleic acid and erucic acid.

The (b) polyoxyalkylene glycol unit constituting the polyether ester amide resin is
Consisting of an oxyalkylene unit having 2 to 4 carbon atoms, 200
Polyoxyethylene glycol, polyoxypropylene glycol, polyoxybutylene glycol, and the like having a molecular weight of up to 8,000 are preferred. Of these, preferred is polyoxyethylene glycol. .

Such a polyetheresteramide resin and a method for producing the same are already known. For example, ring-opening polymerization of a lactam is carried out using an anion catalyst in the presence of a condensed polyester prepolymer composed of a polyether and a dicarboxylic acid. Method (US Pat. No. 3,993,709), a method of heat-polymerizing lactam or ω-aminocarboxylic acid, dicarboxylic acid and polyol (West German Patent Publication No. 2712).
No. 987 and No. 2,936,976), and a method of condensing a dicarboxylic acid amide having a carboxyl group at the molecular chain end with a polyol using a titanate catalyst (US Pat. No. 4,230,838).

As the polyether ester amide resin (B) of the present invention, commercially available products can be used, but preferably the acid value or amine value is 2 mgKOH / g or more,
More preferably, it is 4 mgKOH / g or more. By using a polyetheresteramide resin having an acid value or amine value of 2 mgKOH or more, it is possible to further improve the extrusion processability during melt kneading. The acid value can be measured by, for example, dissolving 1 g of the sample in 50 g of benzyl alcohol and titrating this with KOH methanol solution using phenolphthalein as an indicator. Further, the amine value is obtained, for example, by dissolving 1 g of a sample in 50 g of a phenol / methanol mixed solution, titrating with a hydrochloric acid methanol solution using bromphenol blue as an indicator, and converting it into mg of KOH. High acid number polyether ester amide resin is added during the production of polyether ester amide resin 2
It can be produced by adjusting the amount of carboxylic acid or polyalkylene glycol. On the other hand, high amine number polyether ester amide resins are disclosed, for example, in Japanese Patent Laid-Open No.
It can be manufactured by the method shown in Japanese Patent Publication No. 228691.

The (C) modified vinyl compound polymer used in the present invention is a vinyl compound having at least one reactive functional group selected from the group consisting of acid anhydride groups, epoxy groups and carboxyl groups. It is a polymer. These functional groups can be introduced by means such as copolymerization of a corresponding monomer and a vinyl compound or oxidation of a vinyl compound polymer. The vinyl compound polymer constituting the modified vinyl compound polymer, ethylene, propylene, butene, 4-methylpentene-1, hexene, octene, nonene, decene, homopolymers such as dodecene, styrene, α-methylstyrene, A homopolymer of an aromatic vinyl compound such as vinyltoluene or pt-butylstyrene, or a copolymer of the above α-olefin or aromatic vinyl compound and a copolymerizable monomer (random,
Examples thereof include a block or a graft copolymer).

As the copolymerizable monomer, in addition to α-olefins and aromatic vinyl compounds, conjugated diene components (butadiene, isoprene, piperylene, etc.), non-conjugated diene components (1,4-hexadiene, dicyclopentadiene) are used. , 5-
Ethylidene-2-norbornene, 2,5-norbonadiene, etc.), (meth) acrylic acid ester, vinyl ester (vinyl acetate, etc.), (meth) acrylonitrile, aromatic vinyl monomer (styrene, α-methylstyrene, Vinyl toluene, pt-butyl styrene, etc.), vinyl ether (vinyl methyl ether, etc.), etc. can be illustrated. The degree of polymerization of the vinyl compound, the presence or absence of side chains or branches, the degree of branching, the copolymer composition ratio, etc. are not particularly limited as long as the moldability is not impaired. In addition, in the present specification, “(meta)
"Acrylic" means "acrylic" and / or "methacrylic"
And “(meth) acrylate” means “acrylate” and / or “methacrylate”.

Examples of the monomer having an acid anhydride group or a carboxyl group for introducing a reactive functional group into the vinyl compound polymer include, for example, fats such as (meth) acrylic acid, propylolic acid and crotonic acid. Group unsaturated monocarboxylic acid,
Aromatic unsaturated monocarboxylic acids such as cinnamic acid, maleic anhydride, maleic acid, fumaric acid, itaconic acid, aliphatic unsaturated dicarboxylic acids such as citraconic acid, monomethyl maleate, monoethyl maleate, monobutyl maleate, etc. Examples thereof include unsaturated dicarboxylic acid monoesters such as maleic acid monoesters and fumaric acid monoesters corresponding thereto. Moreover, examples of the monomer having an epoxy group include glycidyl (meth) acrylate and allyl glycidyl ether. The amount of these monomers used for introducing the reactive functional group is, for example, 0.01 to 10% by weight, preferably 0.
It is about 1 to 5% by weight. The average molecular weight of the modified vinyl compound polymer is not particularly limited, and for example, an average molecular weight of about 5,000 to 100,000, particularly 5,000.
It may be about 0 to 50,000.

The preferred modified vinyl compound polymer is modified polyethylene modified with a monomer having a carboxyl group, an acid anhydride group, or an epoxy group (for example, low density, medium density or high density polyethylene, linear low chain). Density polyethylene etc.), modified ethylene-α-olefin copolymer, modified ethylene- (meth) acrylic acid ester copolymer, modified ethylene- (meth) acrylic acid copolymer, modified ethylene-vinyl acetate copolymer, ethylene -Glycidyl (meth) acrylate copolymer, modified polypropylene (for example, polypropylene homopolymer, propylene and α-
Random copolymer with olefin, propylene-α-olefin block copolymer, etc.), modified polystyrene resin (for example, styrene homopolymer, styrene-butadiene copolymer, styrene-acrylonitrile copolymer, styrene-ethylene-acrylonitrile copolymer) Examples thereof include polymers. In these modified vinyl compound polymers, the reactive functional group may be bonded to an end of the polymer or an appropriate site in the polymer chain.

The (D) polyvalent carbodiimide compound used in the present invention means a carbodiimide group (-N =
A compound having at least two C = N-), for example, a polyvalent isocyanate compound having at least two isocyanate groups in the molecule, in the presence of a carbodiimidization catalyst, decarbonation condensation reaction (carbodiimidization reaction) It can be manufactured by performing The carbodiimidization reaction can be carried out by a known method, and specifically, the isocyanate is dissolved in an inert solvent, or the phosporene is dissolved without a solvent in a stream of an inert gas such as nitrogen or under bubbling. Add a carbodiimidization catalyst such as an organic phosphorus compound represented by oxides,
By heating and stirring in the temperature range of 150 to 200 ° C., the condensation reaction (carbodiimidization reaction) accompanied by decarbonization can be promoted.

As the preferred polyvalent isocyanate compound, a bifunctional isocyanate having two isocyanate groups in the molecule is particularly preferable, but an isocyanate compound having three or more isocyanate groups can be used in combination with diisocyanate. . The polyvalent isocyanate compound may be any of aliphatic isocyanate, alicyclic isocyanate and aromatic isocyanate. Specific examples of the polyvalent isocyanate include hexamethylene diisocyanate (HDI), hydrogenated xylylene diisocyanate (H6XDI), xylylene diisocyanate (XDI), 2,2,4-trimethylhexamethylene diisocyanate (TMHDI), 1,12- Diisocyanate dodecane (DDI), norbornane diisocyanate (NBDI), 2,4-bis- (8-isocyanatooctyl) -1,3-dioctylcyclobutane (OCDI), 4,4′-dicyclohexylmethane diisocyanate (HMDI), tetramethylxylyl Diisocyanate (TMXDI), isophorone diisocyanate (IPDI), 2,4,6-triisopropylphenyl diisocyanate (TIDI), 4,4'-diphenylmethane diisocyanate Preparative (MDI), tolylene diisocyanate (TDI), but hydrogenated tolylene diisocyanate (HTDI) and the like, but is not limited thereto. The carbodiimide compound used in the present invention is preferably HMDI or M.
A carbodiimide compound obtained from DI or a commercially available "carbodilide" (trade name; Nisshinbo Co., Ltd.)
Manufactured by Rhein Chemie) may be used.

The polyepoxy compound (E) used in the present invention is a compound having two or more, and more preferably three or more epoxy groups in one molecule.
It can be easily produced by introducing an epoxy group by a known method. For example, a method of oxidizing a compound having a carbon-carbon double bond with a peroxide such as an organic peracid in an inert solvent, a method of treating halohydrin with a base, a compound having a carbonyl group or an aldehyde group and α -A method of reacting a haloester or α-haloketone in the presence of a base,
Alternatively, a method of treating a compound having a carbonyl group or an aldehyde group with a sulfur ylide, a diazo compound, a carbenoid or the like can be mentioned, but the method is not limited to these.
Of course, when producing a polyvalent epoxy compound, it is necessary to use a compound having two or more sites (functional groups) in which the above reaction occurs in one molecule.

Preferred polyhydric epoxy compounds used in the present invention include glycidyl ether compounds of polyhydric alcohols and glycidyl ester compounds of polyhydric carboxylic acids. Specifically, ethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether, trimethylolpropane polyglycidyl ether,
Glycerol diglycidyl ether, glycerol triglycidyl ether, sorbitol polyglycidyl ether, bisphenol A-diglycidyl ether, hydrogenated bisphenol A-glycidyl ether, 4,4′-diphenylmethane diglycidyl ether, terephthalic acid diglycidyl ester, isophthalic acid diglycidyl ester Examples thereof include esters, but are not limited to these.

Further, a preferable polyvalent epoxy compound is a compound having a tertiary nitrogen atom having an autocatalytic ability,
For example, a glycidyl group-substituted amine compound called a polyglycidyl amine type epoxy compound may be mentioned. Specifically, N, N-diglycidylaniline, 4,4'-diphenylmethanediamine-N, N, N ', N'-tetraglycidyl, N, N, N', N'-tetraglycidyl metaxylylenediamine Etc. can be illustrated. A polyglycidylamine type epoxy compound is preferably used as the (E) polyvalent epoxy compound of the present invention,
For example, “TETRAD” (trade name, tetrafunctional epoxy compound, manufactured by Mitsubishi Gas Chemical Co., Inc.) and the like can be mentioned.

The composition of the present invention contains (A) to
In addition to the component (E), as long as the object of the present invention is not impaired,
Furthermore, stabilizers of polyacetal resin, ultraviolet absorbers, pigments, fillers, glass fibers, carbon fibers and other known additives can be added.

The composition of the present invention comprises (A) a polyacetal resin and (B) a polyetheresteramide resin and / or
Alternatively, a polyacetal resin composition containing a modified vinyl compound polymer (C) and a content of (A) of 50 to 99% by weight (this is referred to as a polyacetal resin composition (I)) 1
To 100 parts by weight of (D) polyvalent carbodiimide compound and /
Alternatively, it is a composition containing 0.1 to 5 parts by weight of a polyvalent epoxy compound. In order for the composition of the present invention to give good results, (A) in the polyacetal resin composition (I),
When the weights of (B) and (C) are a, b, and c, respectively, the compounding ratio is preferably in the range of a: (b + c) = 99: 1 to 50:50, and more preferably 95. :
It is in the range of 5 to 70:30. Further, the content of (B) in the polyacetal resin composition (I) is 0 to 50% by weight,
The content of (C) is selected from the range of 0 to 50% by weight. Therefore, the polyacetal resin composition (I) is
Either a two-component system of (A) + (B) or (A) + (C) or a three-component system of (A) + (B) + (C) may be used, but in the polyacetal resin composition (I) The effect of adding (D) and / or (E) is best exhibited in the case of the three-component system. Further, b / c in the three-component polyacetal resin composition (I) is preferably 0.3 or more, more preferably 0.5 or more. b / c
Is 0.3 or less, the compatibility between the (A) polyacetal resin and the (C) modified vinyl polymer is insufficiently improved, and problems such as peeling of the surface layer may occur.

The polyvalent carbodiimide compound (D) and the polyvalent epoxy compound (E) to be blended with the polyacetal resin composition (I) can be used alone or in combination. The addition amount is 0.1 to 5 parts by weight with respect to 100 parts by weight of the polyacetal resin composition (I).
Parts by weight, preferably 0.5 to 3 parts by weight. If the addition amount is less than 0.1 parts by weight, the improvement effect is insufficient, while if it exceeds 5 parts by weight, problems such as increase in mold deposit occur, which is not preferable. Specific effects of the composition of the present invention obtained by adding the (D) polyvalent carbodiimide compound or the (E) polyvalent epoxy compound include (A) polyacetal resin and (B) polyether ester amide resin. The effect of improving impact resistance is remarkable in the two-component system, and the effect of improving weld physical properties is remarkable in the two-component system of (A) polyacetal resin and (C) modified vinyl compound polymer. Furthermore (A) +
In the case of the three-component system of (B) + (C), both the impact resistance improving effect and the weld physical property improving effect are recognized.

Although the mechanism of action of the above-mentioned (D) carbodiimide compound and (E) polyvalent epoxy compound in the composition of the present invention is not clear, the terminal hydroxyl group of the polyacetal resin, the terminal carboxyl group of the polyether ester amide resin, and the terminal hydroxyl group By reacting with hydroxyl group or terminal amino group, acid anhydride group of modified vinyl compound polymer, epoxy group or carboxyl group at the time of melt kneading, the interfacial strength between different resins is improved and cross-linking between the same resins It is presumed that the reaction improves various physical properties of the composition.

The method for producing the composition of the present invention is not particularly limited, and the components (A) to (E) may be blended by a known method. Preferably, the polyacetal resin composition (I) containing the respective components (A), (B) and / or (C) in a predetermined ratio is blended before melt kneading or at the time of melt kneading (D). ) And / or component (E) are added. A known method can be adopted as an addition method. For example, if it is a solid, side feed,
If it is a liquid, it may be added. (D) and / or (E)
Component is inactivated by moisture in the resin and in the atmosphere, the polyacetal resin composition (I) is prepared using a material that has been sufficiently dried, and the moisture is sufficiently removed by providing an oven vent or the like. After that, it is preferable to add these components. Alternatively, (A), (B), (C)
After the composition (I) obtained by melt-kneading the respective components of (1) is sufficiently predried, the components (D) and / or (E) may be added and melt-kneaded again.

To obtain the polyacetal resin composition of the present invention by blending the components (A) to (E) described above, no special method is required, and a known resin blending method can be applied.
For example, a method using a Banbury mixer, an extruder or the like and kneading at a temperature equal to or higher than the melting point or softening point of the above components can be mentioned. The thus-obtained polyacetal resin composition of the present invention is excellent in impact resistance, slidability, and moldability, so that it is used as a muffling gear in the field of electric and electronic devices and as a locking component (for example, by press fitting in the field of automobiles). Stop parts,
It is suitable for applications such as snap fitting locking parts, clips, etc.).

[0029]

EXAMPLES The present invention will be described in more detail with reference to examples below, but the present invention is not limited to these examples as long as the gist thereof is not exceeded. The materials used in the following examples and the methods for evaluation tests of the obtained compositions are as follows. material:

A-1: Polyacetal resin "Iupital F20-01" (trade name, manufactured by Mitsubishi Engineering Plastics Co., Ltd., MI value 3.0 g / 10 min) B-1: Polyether ester amide resin "hydrophilic TP
AE 10HP (acid value 2.1) "(trade name, manufactured by Fuji Kasei Kogyo Co., Ltd.). B-2: Polyether ester amide resin "hydrophilic TP
AE 10HP-A (amine value 4.4) "(trade name, manufactured by Fuji Kasei Kogyo Co., Ltd.). In all of the "hydrophilic TPAE", the soft segment is mainly composed of polyethylene glycol and the hard segment is mainly composed of dimer acid polyamide.

C-1: Modified vinyl compound polymer "Modic-AP M591" (trade name, manufactured by Mitsubishi Chemical Corporation,
Acid anhydride modified LLDPE). C-2: Modified vinyl compound polymer "Bond First"
BF-E "(trade name, manufactured by Sumitomo Chemical Co., Ltd., ethylene-glycidyl methacrylate copolymer). C-3: Modified vinyl compound polymer "Bondayne AX8
390 "(trade name, manufactured by Sumika Atchem Co., Ltd., acid anhydride-modified ethylene-ethyl acrylate copolymer). C-4: Modified vinyl compound polymer "Toughmer MA85
10 "(trade name, manufactured by Mitsui Chemicals, Inc., acid anhydride-modified ethylene-α-olefin copolymer). C-5: Modified vinyl compound polymer "Kraton FG1
901X "(trade name, manufactured by Shell Japan Co., Ltd., acid anhydride-modified styrene-butadiene copolymer).

D-1: Polyvalent carbodiimide compound "carbodilide HMV-8CA" (trade name, Nisshinbo Co., Ltd.)
Made). E-1: Polyvalent epoxy compound "TETRAD-X" (trade name, manufactured by Mitsubishi Gas Chemical Co., Inc.).

Evaluation Test Method Tensile Yield Strength: Test pieces were prepared and measured according to the ASTM D638 method. Tensile breaking elongation: A test piece was prepared and measured according to the ASTM D638 method. Izod impact value: A test piece was prepared and measured according to the ASTM D256 method. Weld strength retention rate: It was determined by measuring the weld tensile strength using a tensile test piece having a weld portion in the central portion prepared according to the ASTM D638 method and then comparing it with the tensile yield strength. Dynamic friction coefficient: A dynamic friction coefficient with a polyacetal resin "Iupital F20-03" manufactured by Mitsubishi Engineering Plastics Co., Ltd. was measured using a thrust friction wear tester. Measurement conditions are linear velocity 100 mm / sec, surface pressure 1
It is 0 kgf.

Examples 1 to 3 and Comparative Examples 1 to 14 Polyacetal resin, polyether ester amide resin, modified vinyl compound polymer, and polyvalent carbodiimide compound were blended in the proportions shown in Tables -1 to -7, respectively. Then, it melt-kneaded at 200 degreeC using the biaxial extruder, and obtained the polyacetal resin composition. With respect to the obtained polyacetal resin composition, the tensile yield strength, the tensile elongation at break, the Izod impact value, the weld strength retention rate, and the dynamic friction coefficient were determined according to the methods described above. The results are shown in Table-1 to Table-7.

Examples 4 to 13 Polyacetal resins, polyetheresteramide resins and modified vinyl compound polymers were blended in the proportions shown in Tables 3 to 7 and then melted at 200 ° C. using a twin-screw extruder. The mixture was kneaded to obtain a polyacetal resin composition (I).
This composition is vacuum dried for at least 4 times at room temperature.
After drying for 8 hours or more, a polyvalent carbodiimide compound or a polyvalent epoxy compound was blended at a ratio shown in Table-2,
It was melt-kneaded again at 200 ° C. using a twin-screw extruder to obtain a polyacetal resin composition. For the obtained polyacetal resin composition, according to the above method, the tensile yield strength,
Tensile elongation at break, Izod impact value, weld strength retention, and dynamic friction coefficient were determined. The results are shown in Table-3 to Table-7.

[0036]

[Table 1]

[0037]

[Table 2]

[0038]

[Table 3]

[0039]

[Table 4]

[0040]

[Table 5]

[0041]

[Table 6]

[0042]

[Table 7]

[0043]

According to the present invention, a polyacetal resin,
Conventionally, melt-kneading due to poor compatibility is achieved by further adding a polyvalent carbodiimide and / or a polyvalent epoxy compound to a composition in which a polyether ester amide resin and a specific modified vinyl compound polymer are mixed in a specific amount ratio. It was difficult to mix different resins, and it is possible to obtain a composition having well-balanced mechanical properties and excellent slidability, and having good extrudability.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) C08L 25:18 23:02) (72) Inventor Daisuke Sanada 5-6-2 Higashi-Hachiman, Hiratsuka-shi, Kanagawa (72) Inventor Takao Kondo 5-6-2 Higashi-Hachiman, Hiratsuka City, Kanagawa Sanryo Engineering Plastics Co., Ltd. Technical Center F-term (reference) 4J002 BB213 BC123 CB001 CL082

Claims (8)

[Claims] 1. At least one reactive functional group selected from the group consisting of (A) polyacetal resin, (B) polyetheresteramide resin and / or (C) acid anhydride group, epoxy group and carboxyl group. 100 parts by weight of a polyacetal resin composition (I) having a modified vinyl compound polymer of (A) content of 50 to 99% by weight, and (D) a polyvalent carbodiimide compound and / or (E) a polyvalent resin. A polyacetal resin composition containing 0.1 to 5 parts by weight of an epoxy compound. 2. The polyacetal resin composition according to claim 1, wherein the content of (B) in the polyacetal resin composition (I) is 0 to 50% by weight. 3. The polyacetal resin composition according to claim 1, wherein the content of (C) in the polyacetal resin composition (I) is 0 to 50% by weight. 4. The polyacetal resin (A) has oxyethylene units in the main chain of polyoxymethylene of 2 to 7.
The polyacetal resin composition according to any one of claims 1 to 3, which is an acetal copolymer containing 5% by weight. 5. The polyacetal resin composition according to claim 1, wherein the soft segment constituent component of the (B) polyether ester amide resin is substantially polyethylene glycol. 6. The dimer acid polyamide obtained by a polycondensation reaction of a polymerized fatty acid and a diamine substantially, as the hard segment constituent component of the (B) polyether ester amide resin. The polyacetal resin composition according to any one of 1. 7. The polyacetal resin composition according to claim 1, wherein the (B) polyether ester amide resin has an acid value or an amine value of 2 mgKOH / g or more. 8. The (C) modified vinyl compound polymer is
Acid anhydride modified polyolefin polymer, acid anhydride modified styrene polymer, acid anhydride modified olefin- (meth) acrylic acid ester copolymer, olefin- (meth) acrylic acid copolymer, olefin- (meth) It is at least 1 sort (s) selected from the group which consists of a glycidyl acrylate copolymer, The polyacetal resin composition in any one of Claims 1-7 characterized by the above-mentioned.