Quantitative analysis of the phase-separated structure and mechanical properties of acrylic copolymer/epoxy thermosetting resin composites

The effects of thermal curing reactivity on phase-separated structures of acrylic copolymer/epoxy thermosetting resin composites were investigated to clarify their phase separation behavior. These composites displayed a sea-island structure, for which the island size altered as the amount of accelerator. The island diameter distribution was represented as a lognormal plot. This phase separation is explained by the law of proportionate effect as observed during the last stage of phase separation via spinodal decomposition.