| 摘要 |
1,232,313. Expandable polymer compositions. FARBWERKE HOECHST A.G. 21 May, 1968 [22 May, 1967], No. 24283/68. Headings C3C and C3P. An expandable polymer composition is made by homopolymerizing or copolymerizing in aqueous suspension a monomeric material comprising from 55 to 100% by weight of one or more monoalkenyl aromatic monomers having the general formula in which Ar is a monovalent aromatic radical and R is a hydrogen atom or a methyl group, and from 0 to 45% by weight of one or more other ethylenically unsaturated monomers, the polymerization being carried out in the presence of from 0À25 to 2À0% by weight of one or more elastomers, based upon the weight of the monoalkenyl aromatic monomer(s) and if present the ethylenically unsaturated monomer(s), a blowing agent being introduced at any stage in the process so that the homopolymer or copolymer formed has the blowing agent incorporated therein. The elastomer may be a styrenebutadiene copolymer or polybutadiene. The blowing agent may be pentane. |
