| 摘要 |
A process for reducing the molecular weight of isotactic polystyrene comprises thermal and/or mechanical depolymerization in the presence of a chain transfer agent or a rubber antioxidant. Specified antioxidants are 2, 2, 4-trimethyl-1, 2-dihydroquinone, 6-ethoxy-2, 2, 4-trimethyl-1, 2-dihydroquinoline, 4, 41-thio-bis (3-methyl-6-t-butyl phenol), 2, 21-methylene-bis (4-methyl-6-t-butyl phenol), hydroquinone-monobenzyl ether, 2, 5-di-t-butylhydroquinone, N, N1-diphenylethylenediamine, p, p1-methylene-dianiline, lauryl mercaptan and p-(p-tolysulphonyl-amide) diphenylamine. The specified transfer agents are aromatic peroxides and hydroperoxides, azo-compounds and mercaptans, e.g. t-butyl peroxide, benzoyl peroxide, lauryl mercaptan, and azo-bis (isobutyronitrile). Specifications 810,023 and 828,791 are referred to. |
