Synthesis of graft copolymer of styrene and acrylonitrile onto poly (butyl acrylate) by using polymeric peroxide

Two-stage seeded emulsion copolymerization of butyl acrylate with tert-butyl 3-isopropenylcumylperoxide (D120) was performed at 70degreesC. Copolymer latex with 0.2mum of particle size was obtained. Emulsion graft polymerization of styrene and acrylonitrile onto the copolymer of butyl acrylate was initiated by peroxy bonds in the D120 units of the backbone chains at 120degreesC. Graft copolymers with higher grafting ratio were derived. It was found that the grafting ratio tends to increase with the increasing D120 in feed of copolymerization with butyl. acrylate. The graft copolymers were blended with SAN resin, and a kind of AAS resin was obtained. Both elongation at break and Izod impact strength of the AAS resin reached maximum at grafting ratio of 0.25, which were comparable with the values of ABS resin for general purpose. A. method to improve the grafting efficiency on the saturated polyacrylate elastomer rubber was developed.