| 摘要 |
A solid thermoplastic interpolymer is made by emulsion polymerizing 85 to 65 parts by weight of methyl methacrylate or mixtures of at least 55% thereof with a polymerizable compound having a single vinylidene group, e.g. ethyl acrylate, acrylonitrile, vinylidene chloride and styrene, but excluding vinyl pyridine, and 15 to 35 parts by weight of a copolymer containing by weight 90 to 50% of butadiene and 10 to 50% of styrene and having a molecular weight within the range of 25,000 and 1,500,000, the weight of the ingredients making a total of 100 parts, the polymerization being carried out at a temperature of from 15 DEG to 80 DEG C. in the presence of a catalyst, e.g. benzoyl peroxide, methyl ethyl ketone peroxide, tertiary-butyl, cumene and paramenthane hydroperoxides, potassium persulphate and azoisobutyronitrile, and a regulator, e.g. octyl, dodecyl, tertiary dodecyl and benzyl mercaptans, nitrohydrazines and carbon tetrachloride. Also present in the polymerization emulsion may be emulsifiers, e.g. sodium oleate and sodium lauryl sulphate. In an Example (9) the catalyst consists of a mixture of tertiary-butyl hydroperoxide, ferrous sulphate and sodium formaldehyde sulphoxylate. |
