Process for preparing an impact-resistant thermoplastic moulding compound

Claim 1

Process for preparing an impact resistant and U.V. resistant thermoplastic moulding compound based on a copolymer consisting of styrene and/or α-methylstyrene and maleic anhydride comprising mixing: (A) about 50 about 95 wt. % of a copolymer consisting of: (i) about 50 to about 95 wt. % styrene and/or α-methylstyrene, (ii) about 50 to about 5 wt. % maleic anhydride, (iii) 0 to about 20 wt. % acrylate, (iv) 0 to about 20 wt. % acrylonitrile; (B) about 5 to about 50 wt. % of a rubber selected from the group consisting of: a rubber modified with hydroxyl groups, said modified rubber being obtained by grafting thereto, by solution polymerization, a compound having hydroxyl groups selected from the group consisting of 2-hydroxyethylacrylate, 2-hydroxypropylacrylate, 2-hydroxyethylmethacrylate, 2-hydroxypropylmethacrylate, allyl alcohol and vinyl benzyl alcohol, the hydroxyl modified rubber containing about 0.05 to 10 wt. of hydroxyl groups, a rubber modified with amine groups, said modified rubber being obtained by grafting thereto, by solution polymerization, a compound having amine groups, and a rubber modified with amide groups, said modified rubber being obtained by grafting thereto, by solution polymerization, a compound having amide groups; and (C) about 0 to about 30 wt. % unmodified rubber, wherein said rubber is ethylene-propylene rubber, ethylene-propylene-diene rubber, polyacrylate, polybutyldiene, polybutylene, polyethylene-vinyl acetate or a mixture thereof; said mixing being conducted in the presence of about 0.01 to about 10 parts by weight of a reaction accelerator, calculated on 100 parts by weight copolymer and modified rubber, at a temperature between about 160° C. and about 290° C. wherein said reaction accelerator is (a) an organic metal compound, the metal component of which is a group II, III and/or IV metal or (b) an organometal compound.