| abstract |
1,169,323. Copolymer beads. PERMUTIT CO. Ltd. 8 April, 1968 [6 April, 1967; 22 Jan., 1968], Nos. 15255/68 and 3293/68. Heading C3P. Copolymer beads of average diameter 1-100 Á are produced by the suspension polymerization of a mixture comprising at least one monomer containing one polymerizable double bond and at least one monomer containing two or more double bonds, the polymerization mixture containing the monomers as the major constituent and also containing 2-20% by wt. of at least one polymer that is soluble in the monomeric mixture but insoluble in the copolymer and that increases the ability of the copolymer to cling to the human skin. The polymer may be polyisobutylene, polyethylene glycol or polypropylene glycol. In the examples the copolymer is produced by polymerizing styrene, divinylbenzene and optionally hydroxyethyl methacrylate in the presence of the above polymer, titanium dioxide, a dye, benzoyl peroxide and an aq. solution of polyvinyl alcohol (which may contain sodium chloride). |