| 摘要 |
A polymeric composition with resistance to stress-cracking comprises: (a) a small amount, e.g. 0.1 to 2 parts by weight of p,p1-diamino-diphenylmethane or a C2-C6 aliphatic diamine, and (b) 100 parts by weight of a thermoplastic composition consisting of at least 25 parts of a graft copolymer and correspondingly not more than 75 parts of a separately prepared resinous copolymer, the graft copolymer being obtained from 25 to 95 parts of styrene and acrylonitrile in a ratio of from 65:35 to 90:10 on, correspondingly, 75 to 5 parts of polybutadiene, and the resinous copolymer, when present, being a copolymer of from 65 to 90 parts of styrene or alpha-methyl styrene and, correspondingly, from 35 to 10 parts of acrylonitrile. Specified aliphatic diamines are ethylenediamine and hexamethylenediamine. Specifications 766,622, 770,856 and 794,400 are referred to.
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