| 摘要 |
<p>1430447 Grafted diene polymers STANDARD OIL CO 28 June 1973 [27 July 1972] 30786/73 Heading C3G A process for preparing an impact-resistant, gas-barrier resin comprises polymerized in an aqueous emulsion 100 parts by weight of: (A) at least 70% by weight of alpha, betaolefinically unsaturated acrylonitrile having the structure CH 2 = CRCN wherein R is hydrogen, alkyl (C 1 -C 4 ), or halogen; and (B) an amount of up to 30% by weight based on the combined weights of (A) and (B) of an ester of an olefinically unsaturated carboxylic acid having the structure CH 2 = C(R 1 )COOR 2 wherein R 1 is hydrogen, alkyl (C 1 -C 4 ) or halogen and R 2 is alkyl (C 1 -C 6 ) in the presence of 1-40 parts by weight of ; (C) a copolymer of a conjugated diene monomer which is butadiene-1,3 or isoprene and an olefinically unsaturated nitrile having the structure CH 2 = CRCN wherein R has the foregoing designation, said copolymer containing from more than 50% to 95% by weight of polymerized conjugated diene monomer, and from 5% to less than 50% by weight of polymerized olefinically unsaturated nitrile, and said copolymer containing 10-60% by weight of gel and having been prepared to at least 75% conversion in the presence of 0À2-1À5 p.h.m. of a mercaptan to obtain the requisite gel content. In the specific examples there is disclosed processes in which: (1) 75 parts by weight of acrylonitrile and 25 parts by weight of methyl acrylate are graft polymerized in the presence of 9 parts by weight of a rubber latex comprising butadiene- 1,3 and acrytlonirile in a weight ratio of 70 : 30; and (2) 95 parts by weight methacrylonitrile and 5 parts by weight methyl methacrylate are graft polymerized in the presence of 20 parts by weight of a rubber latex comprising butadiene- 1,3 and acrylonitrile in a weight ratio of 65: 35. Comparative examples are given in which the copolymer has a gel content outside the range 10-60%.</p> |
