| 摘要 |
1,169,652. Cellular PVC. W. R. GRACE & CO. 4 Dec., 1967 [5 Dec., 1966], No. 55092/67. Headings C3C and C3P. Cellular ribs on a plate separator for storage batteries are produced by heating a mixture of polyvinylehloride, an ethylenically unsaturated, cross-linking, plasticizer composition, a free radical catalyst to polymerize the plasticizer and a blowing agent. The plasticizer is a dialkyl maleate or fumarate e.g. diisooctyl fumarate mixed with maleic anhydride and a minor amount of allyl phthalate. Di-tert. butyl peroxide or azobisisobutyronitrile is added as catalyst. The blowing agent is azodicarbonamide, dinitrosopentamethylene tetramine, diazoaminobenzene, p,p<SP>1</SP>-oxybis (benzene sulphonyl hydrazide), sodium carbonate, ammonium carbonate or ammonium bicarbonate and is preferably used with a catalyst, particularly zinc octonate. A conventional ester plasticizer, particularly dioctyl phthalate is preferably also present and fillers, stabilizers, pigments and dispersing agents are also specified. |
