Fire retarding polypropylene composition
AssigneeCompression Polymers Group
InventorJerry Wagner
Life of this patent
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Abstract
A fire retarding polypropylene composition comprising a copolymer of polypropylene and an ethylene/propylene rubber, and at least about 50% by weight but not greater than 60% by weight of a magnesium hydroxide coated with an anionic surface active agent, the magnesium hydroxide having (i) a strain in the <101> direction of not more than 3.0×10−3, (ii) a crystallite size in the <101> direction of more than 800 Å, and (iii) a specific surface area, determined by the BET method, of less than 20 mg2/g. The composition can be used in a fire retarding semiconductor apparatus which passes the FMRC Clean Room Materials Flammability Test Protocol.
Claims11
A method of making a clean room surface component comprised of composition, wherein said composition comprises:
- (a) a copolymer polypropylene resin in which ethylene/propylene rubber has been grafted onto the polypropylene chains;
- and
- (b) at least about 50% but not greater than 60% by weight of a magnesium hydroxide coated with an anionic surface agent,
- wherein said method includes the steps of:
- (a) forming pieces from said composition, said pieces being adapted to form said clean room surface component;
- and
- (b) bonding said pieces using thermoplastic welding to make a semiconductor clean room component.
A clean room component, said clean room component comprising a polymer and magnesium hydroxide composition, the composition comprising a copolymer polypropylene resin in which ethylene-propylene rubber has been grafted onto the polypropylene chains, and at least about 50% but not greater than 60% by weight of a magnesium hydroxide coated with an anionic surface active agent, the magnesium hydroxide having:
- (i) a strain in the <101> direction of not more than 3.0×10−3,
- (ii) a crystallite size in the <101> direction of more than 800 Å, and
- (iii) a specific surface area, determined by the BET method, of less than 20 mg2/g;
- said composition being adapted to meet FMRC standards for use in a clean room.
A method for producing a fire retarding clean room component, said method comprising the steps of:
- (a) mixing a copolymer polypropylene resin in which ethylene/propylene rubber has been grafted onto the polypropylene chain with at least about 50% but not greater than 60% by weight of a magnesium hydroxide coated with an anionic surface active agent, the magnesium hydroxide having:
- (i) a strain in the <101> direction of not more than 3.0×10−3,
- (ii) a crystallite size in the <101> direction of more than 800 Å, and
- (iii) a specific surface area, determined by the BET method, of less than 20 mg2/g at a temperature above a melting point of the copolymer to form a blend;
- and,
- (b) forming said blend into said clean room component.
A compression molded clean room surface component comprised of a fire retarding polypropylene composition, wherein the composition comprises:
- (a) a copolymer polypropylene resin in which ethylene/propylene rubber has been grafted onto the polypropylene chains;
- and
- (b) at least about 50% but not greater than 60% by weight of a magnesium hydroxide coated with an anionic surface agent.
A method of making a clean room surface component comprising the steps of:
- (a) providing a composition including a copolymer polypropylene resin in which ethylene/propylene rubber has been grafted onto the polypropylene chains;
- and at least about 50% but not greater than 60% by weight of a magnesium hydroxide coated with an anionic surface agent, the magnesium hydroxide having:
- (i) a strain in the <101> direction of not more than 3.0×10−3,
- (ii) a crystallite size in the <101> direction of more than 800 Å, and
- (iii) a specific surface area, determined by the BET method, of less than 20 mg2/g;
- and
- (b) compression molding said composition to make a clean room surface component.
Dependencies are inferred from the claim text.