Self-healing performance of polymeric material with microcapsules and imidazoline derivatives curing agent

Abstract

A self-healing system of polymeric materials was provided by two-component healing system consisting of epoxy-containing microcapsules and anionic polymerization initiated 2MZ-AZINE (imidazoline derivatives) latent hardener. When cracks were initiated or propagated in the composites, the embeded microcapsules would be damaged and the epoxy healing agent would be released. The latent hardener can be well dispersed in epoxy matrix during composites manufacturing, and hence activate the released epoxy wherever it is. As a result, self-healing of the cracked sites is successfully achieved through curing of the released epoxy healing agent. In this paper, self-healing ability of the epoxy filled with the healing system was evaluated. It was found that the distribution of microcapsules and latent curing agent greatly influences the healing efficiency but not the stoichiometric composition, and the optimal weight ratio of microcapsules and curing agent 2MZ-AZINE are 15 wt% and 2 wt%, offering a ~83% healing efficiency.