Morphology and mechanical properties of Acrylonitrile-styrene-acrylate toughened plastics with block copolymer chain structure

Acrylonitrile-styrene-acrylate (ASA) toughened plastics based on block copolymers are successfully prepared via RAFT emulsion polymerization and various molecular structures are designed to have different morphologies in order to investigate the relationship between morphologies and mechanical properties. All materials prepared by blending exhibit sea-island morphology. Promoting particles dispersion and increasing spherical particle size shorten surface-to-surface interparticle distance and help to improve tensile properties of materials. Enlarging particles through crosslinked structures are found to be a more effective method to improve tensile toughness, at the cost of a slight reduction in tensile yield strength. Larger spherical particles with crosslinked structures are found to help improving the Izod notched impact strength of materials. However, the existence of a SAN core decreases the material's ability to withstand impact. Compared to blended samples, triblock copolymer materials display higher flexural strength with equal flexural modulus. POLYM. ENG. SCI., 59:389–395, 2019. © 2018 Society of Plastics Engineers