| 摘要 |
<p>New rigid PVC foam (I) has a density of 10-50 kg/cubic metre and has a uniform, fine-celled cell-structure with closed cells of which at least 95% have a cell diameter of at most 300 microns. (I) consists of a rigid vinyl chloride homopolymer (II) contg., per 100 pts. wt. of polyvinyl chloride (III), 0.1-15 pts. wt. of a homo- or copolymer of an alkyl (1-10C) methacrylate pref. methyl methacrylate, and foamed using a physical blowing agent (IV). (I) is produced by foaming (II) with 5-50 pts. wt. of (IV), per 100 pts. wt. (III). Pref. (IV) is one or more fluorochloroalkanes, esp. trichlorofluoromethane and/or dichloro difluoro methane. (5pp).</p> |
