Polyacetal resin composition and sliding member

Patent metadata

Field	Value
Publication number	US-9969875-B2
Application number	US-201515548994-A
Country	US
Kind code	B2
Filing date	Nov 30, 2015
Priority date	Mar 20, 2015
Publication date	May 15, 2018
Grant date	May 15, 2018

Abstract

A polyacetal resin composition which not only is highly inhibited from making creaking sounds but also has satisfactory performances with respect to other properties. The polyacetal resin composition includes 100 parts by weight of a polyacetal resin, 0.01-1 part by weight of a hindered phenolic antioxidant, 0.01-1 part by weight of a nitrogenous compound, 0.1-1 part by weight of a graft copolymer, 0.1-1 part by weight of a fatty acid ester, 0.5-5 parts by weight of a silicone oil, and 0.1-1 part by weight of calcium carbonate. The nitrogenous compound may be an aminotriazine compound, the graft copolymer includes an olefin-based polymer as the main chain and a vinyl-based polymer as side chains, the fatty acid ester includes a C12-32 fatty acid and a C2-30 mono- or polyhydric alcohol, and the calcium carbonate has an average particle diameter of 1 μm or smaller.

First claim

The invention claimed is:

1. A polyacetal resin composition, comprising 100 parts by weight of a polyacetal resin (A),
0.01 parts by weight to 1 part by weight of a hindered phenolic antioxidant (B),
0.01 parts by weight to 1 part by weight of a nitrogenous compound (C),
0.1 parts by weight to 1 part by weight of a graft copolymer (D),
0.1 parts by weight to 1 part by weight of a fatty acid ester (E),
0.5 parts by weight to 5 parts by weight of a silicone oil (F), and
0.1 parts by weight to 1 part by weight of calcium carbonate (G), wherein
the nitrogenous compound (C) is at least one selected from the group consisting of an aminotriazine compound, a guanamine compound, a hydrazide compound, and a polyamide compound,
the graft copolymer (D) has an olefin-based polymer (d1) as a main chain, and comprises a vinyl-based polymer (d2) as a side chain,
the fatty acid ester (E) is constituted from a fatty acid with a carbon number of 12 to 32, and a monohydric or polyhydric alcohol with a carbon number of 2 to 30, and the calcium carbonate (G) has an average particle diameter of 1 μm or less.

2. A polyacetal resin composition according to claim 1 , wherein the graft copolymer (D) comprises an acrylonitrile-styrene-graft-polyethylene resin.

3. A polyacetal resin composition according to claim 1 or 2 , wherein the silicone oil (F) has a kinematic viscosity at 25° C. of 50,000 cSt (500 cm 2 /s) or more.

4. A sliding member constituted from a resin molded article comprising the polyacetal resin composition according to claim 1 or 2 .

Assignees

• Polyplastics Co

Inventors

• Shimoda Akihide
• Katsuchi Hirokazu

Classifications

• C08K3/26 Primary

  Carbonates; Bicarbonates · CPC title

• C08K5/13

  Phenols; Phenolates · CPC title

• C08L51/04

  grafted on to rubbers · CPC title

• C08L59/00 Primary

  Compositions of polyacetals; Compositions of derivatives of polyacetals (of polyvinyl acetals C08L29/14) · CPC title

• C08L83/04

  Polysiloxanes · CPC title