| 摘要 |
<p>1,260,377. Vinyl chloride terpolymers. PRODUITS CHIMIQUES PECHINEY-SAINTGOBAIN. 22 April, 1969 [22 April, 1968], No. 20552/69. Heading C3P. Terpolymers based on (1) vinyl chloride, (2) a vinyl ester, halogenated vinyl derivative or acrylic derivative and (3) an olefinic hydrocarbon of low molecular weight, are prepared by a bulk polymerization process comprising, in a first stage prepolymerizing under high speed agitation the whole of the vinyl chloride required or a monomer composition based on part of the vinyl chloride required, until a limited conversion of the monomer or monomer composition has taken place, then bringing the prepolymerizate into contact with the olefinic hydrocarbon and any remaining part of the vinyl chloride and carrying out, in a second stage, a final polymerization under a low speed agitation, the monomer (2) being introduced either in full at the beginning of the first or second stage or part at the beginning of the first stage and the remainder at the beginning of the second stage. The olefinic hydrocarbon may be ethylene, propylene, isobutene, butene-1 and cis and trans butene-2. The compound (2) may be vinyl acetate, vinylidene chloride, an acrylic or methacrylic ester or acrylonitrile. Polymerization catalysts used in methylphthalate solution are ethylhexyl peroxydicarbonate, acetylcyclohexanesulphonyl peroxide, and octylperoxydicarbonate.</p> |
