Toughening polystyrene by core-shell grafting copolymer polybutadiene-graft-polystyrene with potassium persulfate as initiator

Core-shell polybutadiene-graft-polystyrene rubber particles with different ratios of polybutadiene core to polystyrene shell were synthesized by an emulsion polymerization using K2S2O8 as an initiator. Then the core-shell rubber particles were blended with PS to prepare PS/PB-g-PS. The rubber particles with a size of 0.3-0.5 mu m could toughen polystyrene significantly. The mechanical properties, morphologies and deformation mechanisms of samples were extensively investigated. The experimental results showed that the dispersion of rubber particles in a cluster state leads to better impact resistances. Crazing occurred from rubber particles and extended in a bridge-like manner to neighboring rubber particles parallel to the equatorial direction. (C) 2012 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.