Polyolefin resin composition containing fibrous inorganic filler

• US 4,987,173 A
• Filed: 12/22/1988
• Issued: 01/22/1991
• Est. Priority Date: 11/13/1985
• Status: Expired due to Fees

• Current Assignee: Idemitsu Petrochemical Co., Ltd. (Idemitsu Kosan Company Limited)
• Original Assignee: Idemitsu Petrochemical Co., Ltd. (Idemitsu Kosan Company Limited)
• Inventors: Nomura, Manabu, Kihara, Kazuaki, Tomomatsu, Ryuzo
• Primary Examiner(s): Jacobs, Lewis T.
• Assistant Examiner(s): Woodward, David W.
• Application Number:
  US07/288,098
• Time in Patent Office: 761 Days
• Field of Search: 524/423, 524/436, 524/525
• US Class Current: 524/423
• CPC Class Codes: C08K 2201/016 Additives defined by their aspect ratio
• CPC Class Codes: C08K 7/08 Oxygen-containing compounds
• CPC Class Codes: C08L 23/02 not modified by chemical after-treatment

Abstract

A polyolefin resin composition comprising from 30% to 96% by weight of a polyolefin, from 3% to 50% by weight of a fibrous inorganic filler selected from the group consisting of a magnesium hydroxide fiber, a magnesium oxide fiber, and a gypsum fiber having a mean fiber diameter of from 0.1 to 2 μm and an aspect ratio of from 20 to 100 or a mixture of two or more of said inorganic fillers, and from 1% to 60% by weight of a thermoplastic elastomer.

The said composition provides a molded material which has a good external appearance and is excellent in the impact strength, rigidity, and heat stability.

Claims

1. A polyolefin resin composition prepared by kneading a mixture comprising from 40 to 92% by weight of a polyolefin, from 5 to 30% by weight of a fibrous inorganic filler, and from 3 to 30% by weight of a thermoplastic elastomer based on the total amount of the mixture, the polyolefin being selected from the group consisting of a crystalline polypropylene, a crystalline polypropylene containing a polyethylene component, and a mixture of a crystalline polypropylene and a polyethylene, the fibrous inorganic filler having a mean fiber diameter of from 0.1 to 2 μ

m and an aspect ratio of from 50 to 100 and being selected from the group consisting of a magnesium hydroxide fiber, a gypsum fiber, and mixtures thereof, and the thermoplastic elastomer being selected from the group consisting of an ethylene propylene rubber, an ethylene propylene diene rubber, and a styrene butadiene rubber.

2. The polyolefin resin composition as claimed in claim 1 wherein said crystalline polypropylene containing a polyethylene component is a crystalline propylene ethylene block copolymer.

3. The polyolefin resin composition as claimed in claim 1 wherein said mixture of a crystalline polypropylene and a polyethylene is a mixture consisting of from 5 to 30% by weight of a polyethylene and from 95 to 70% by weight of a crystalline propylene ethylene block copolymer.

4. The polyolefin resin composition as claimed in claim 1, wherein the fibrous inorganic filler is magnesium hydroxide fiber.

5. A polyolefin resin composition prepared by kneading an admixture comprising 100 parts by weight of a polyolefin resin composition mixture comprising from 40 to 92% by weight of a polyolefin, from 5 to 30% by weight of a fibrous inorganic filler, and from 3 to 30% by weight of a thermoplastic elastomer based on the total amount of the mixture, the polyolefin being selected from the group consisting of a crystalline polypropylene, a crystalline polypropylene containing a polyethylene component, and a mixture of a crystalline polypropylene and a polyethylene, the fibrous inorganic filler having a mean fiber diameter of from 0.1 to 2 μ

m and an aspect ratio of from 50 to 100 and being selected from the group consisting of a magnesium hydroxide fiber, a gypsum fiber, and mixtures thereof, and the thermoplastic elastomer being selected from the group consisting of an ethylene propylene rubber, an ethylene propylene diene rubber and a styrene butadiene rubber, and from 3 to 30 parts by weight of talc having a mean particle diameter of from 0.1 to 10 μ

m or mica having a mean particle diameter of from 30 to 300 μ

m.

6. The polyolefin resin composition as claimed in claim 5, wherein the fibrous inorganic filler is magnesium hydroxide fiber.

7. The polyolefin resin composition as claimed in claim 5 wherein said crystalline polypropylene comprising a polyethylene component is a crystalline propylene ethylene block copolymer.

8. The polyolefin resin composition as claimed in claim 5 wherein said mixture of a crystalline polypropylene and a polyethylene is a mixture consisting of from 5 to 30% by weight of a polyethylene and from 95 to 70% by weight of a crystalline propylene ethylene block polymer.