Abstract:
The invention relates to a process for producing moulding compositions containing: a) from 55 to 85% by weight of copolymer A composed of vinylaromatic monomer A1 and a,B-unsaturated monomer A2; b) from 15 to 45% by weight of graft copolymer B with particle size from 50 to 550 nm composed of: B 1: from 60 to 80% by weight of rubbery graft base B 1 composed of: B11: from 80 to 99% by weight of at least one C2-C8-alkyl acrylate, B12: from 0.5 to 2.5% by weight of cyclic crosslinking agent, B13: from 0 to 2% by weight of non-cyclic crosslinking agent, B2: from 20 to 40% by weight of at least one graft shell B2 composed of: B21: from 60 to 75% by weight of a styrene, B22: from 25 to 40% by weight of acrylonitrile, c) from 0 to 10% by weight of additives C; where the reaction time of the polymerization for producing the graft base B 1 is in the range from 2 to 5 h, and the addition of the starting materials takes place over at least two chronological segments.
Abstract:
The invention relates to a thermoplastic composition containing the components A and B and optionally the additional components C and D, the sum of which equals 100 wt. %. The molding compound consists of: a) 60 to 75 wt. % of one or more styrene copolymers A, b) 25 to 40 wt. % of one or more graft copolymers B, c) 0 to 15 wt. % of a rubber C which is different from component B, and d) 0 to 5 wt.% of one or more additives D. The composition contains 0.2 to 3.0 wt. %, based on the total weight of the components A to D, of oligomers, can be readily processed, and leads to scratch-resistant molded parts.
Abstract:
A process for producing a thermoplastic molding composition comprising: 10% to 40% by weight of a graft copolymer A comprising 50% to 70% by weight, based on A, of a graft base A1 formed from an elastomeric, crosslinked acrylic ester polymer and 30% to 50% by weight of a graft shell A2, 50% to 90% by weight of a hard matrix B formed from copolymers of styrene or α-methylstyrene and acrylonitrile, 0% to 50% by weight of a further graft copolymer C, 0% to 15% by weight of additives D, wherein the reaction for preparation of the acrylic ester polymer A and/or the reaction for preparation of C is conducted in the presence of 0.01 to 4 times the molar amount of sodium carbonate, based on the sum total of the molar amount of initiator used in the preparation of the graft base and graft shell, leads to lower coagulate formation.
Abstract:
Thermoplastic moulding compositions containing: from 55 to 85% by weight of a copolymer A composed of styrene and acrylonitrile, from 10 to 40% by weight of at least one graft copolymer B composed of B1: from 50 to 80% by weight, preferably from 60 to 70% by weight, of crosslinked acrylate polymer B1 with average particle diameter from 300 to 700 nm as graft base B1, B2: a first graft shell B2 made of from 5 to 30 of a vinylaromatic monomer B21, and B3: a second graft shell B3 made of from 15 to 40 of a mixture of vinylaromatic monomers B31 and nitrile monomers B32, where these are present in a ratio by weight of from 4:1 to 3:2, and from 0 to 5% by weight of additives and/or auxiliaries C, have particular mechanical properties when the content of acrylonitrile in the copolymer component A and the content of acrylonitrile in the graft shell B3 differ by at least 8% by weight.