Foamable composition of vinyl chloride polymers and method of producing open cell sheet
AssigneeOtsuka Kagaku Yakuhin Kabushiki Kaisha
InventorsNormitsu Tsurushige, Toshinori Takao, Shinichi Yamada
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Abstract
This invention provides a foamable composition of vinyl chloride polymers comprising a vinyl chloride polymer, a plasticizer, a synthetic hydrocarbon wax, an alkali metal-zinc stabilizer and a decomposable organic blowing agent; and a method of producing an open cell sheet of vinyl chloride polymers comprising shaping the foamable composition into a sheet-like body and heating the resulting shaped body.
Claims13
A foamable composition of vinyl chloride polymers for preparation of an open cell sheet, comprising:
- (i) 100 parts by weight of a vinyl chloride
- (ii) 30 to 150 parts by weight of a plasticizer;
- (iii) 1 to 8 parts by weight of a synthetic hydrocarbon wax prepared by a process selected from the group consisting of depolymerization of polyethylene, polymerization of ethylene and the Fischer-Tropsch synthesis of coal gas, said wax having a molecular weight of 1,500 to 7,000, a softening point of 90.degree. to 135.degree. C. and an average particle size of 10 to 100 .mu.m,
- (iv) 1 to 5 parts by weight of an alkali metal-zinc stabilizer and
- (v) 2 to 10 parts by weight of a decomposable organic blowing agent containing at least 60% by weight of azodicarbonamide.
A method of producing an open cell sheet of vinyl chloride polymers comprising the steps of shaping a foamable composition of vinyl chloride polymer into a sheet, the composition comprising:
- (1) 100 parts by weight of a vinyl chloride polymer;
- (ii) 30 to 150 parts by weight of a plasticizer;
- (iii) 1 to 8 parts by weight of a synthetic hydrocarbon wax prepared by a process selected from the group consisting of depolymerization of polyethylene, polymerization of ethylene and the Fischer-Tropsch synthesis of coal gas, and having a molecular weight of 1,500 to 7,000, a softening point of 90.degree. to 135.degree. C. and an average particle size of 10 to 100 .mu.m;
- (iv) 1 to 5 parts by weight of an alkali metal-zinc stabilizer and
- (v) 2 to 10 parts by weight of a decomposable organic blowing agent containing at least 60% by weight azodicarbonamide, and heating the resulting sheet at a temperature not lower than the temperature at which the blowing agent undergoes decomposition in the sheet.
Dependencies are inferred from the claim text.