MECHANICAL EFFECTS ACCORDING TO THE TYPE OF POLY(STYRENE-CO-METHYL METHACRYLATE) COPOLYMERS AT POLYSTYRENE POLY(METHYL METHACRYLATE) INTERFACES/

The effects of incorporating a thin layer of various types of polystyr ene-poly(methyl methacrylate) copolymers, i.e. block, random, and graf t copolymer on the interfacial adhesion between PS and PMMA have been investigated. The fracture toughness of the interface was measured usi ng an asymmetric double cantilever beam fracture test and the enhanced toughness effect of copolymers was compared. The fracture toughness o f the interface increased with increasing layer thickness of the copol ymer and each copolymer had the layer thickness of saturated fracture toughness. The fracture toughness increased in the order of block > gr aft > random copolymer. Copyright (C) 1996 Elsevier Science Ltd.