Toughness of epoxies modified by preformed acrylic rubber particles

Abstract

A bisphenol-A diglycidyl ether resin, cured with isophoronediamine at 6OOC. was modifled by means of preformed core-shell acrylic rubber particles. Blends with rubber contents u p to 30 phr by wt were tested. The fracture toughness depended linearly on the amount of rubber and significant improvement was found. No deterioration of temperature resistance was also observed. The viscosity of resin/modifier mixtures was controlled by means of antifoaming a ents. A comparison with liquid acrylonitrilebutadiene copcfymers showed that core-shell particles are efflcacious tougheners. The effect of a bimodal particle size distribution was considered. In the size range investigated (0.2+5pn) no synergic effect was observed. 0 1991 Hiithig & Wepf Verlag, Basel CCC 0258-0322/91/$02.00

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