Preparation and characterization of dual-curable off-stoichiometric amine-epoxy thermosets with latent reactivity

A new family of dual-curable poly(hydroxyamine)-poly(ether) thermosets based on off-stoichiometric amine-epoxy formulations has been prepared and characterized. The first curing stage was a self-limiting click epoxy-amine polycondensation with an excess of epoxides and the second stage was an anionic homopolymerization of the unreacted epoxy groups, initiated by a latent base. The curing process was sequential with storage stable intermediate materials. The latency of these partially-cured intermediate materials was established not only by a thermally activated base generator, but also by the vitrification of the formulations. The intermediate and final materials exhibit a wide range of properties depending on the relative contribution of both curing stages. Intermediate materials can either be shape conformable solids, or liquids that are applicable as adhesives. Fully cured materials exhibit shape-memory effect. (C) 2018 Elsevier Ltd. All rights reserved.