| abstract |
Production of emulsive copolymer ABS with separately prepared copolymer SAN progresses so that the emulsive copolymer ABS is prepared by radical polymerisation of a mixture of a vinyl aromatic compound with the group of styrene, alphamethylstyrene, paramethylstyrene with acrylonitrile, whereas the mixture contains 10 to 35 % by weight acrylonitrile. Radical polymerisation occurs until the conversion of 90 to 99 % in the presence of two elastomer latexes, whose particle size is 40 to 190 nm and 200 to 800 nm and their polymers are in a mass ratio of 90:100 to 10:90. This emulsive copolymer ABS is mixed with the copolymer SAN, whose content of bound acrylonitrile is not higher than 8 % by weight in comparison with the abovementioned monomeric mixture. The content of rubber compounds, in the ABS emulsive copolymer at 12 to 29 %, makes 10 to 25 % in the mixture of emulsive copolymer ABS with copolymer SAN at 10 to 25 %. The mixture is homogenised in the form of a melt at 453 to 553 K. The index of that melt of emulsive copolymer ABS and copolymer SAN is 1 to 40 g/10 min. and 5 to 120 g/10 min. at 493 K. |