Free-radical frontal polymerization with a microencapsulated initiator: Characterization of microcapsules and their effect on pot life, front velocity, and mechanical properties

In this study, microcapsules containing a cumene hydroperoxide (CHP) core were produced by interfacial polymerization and tested in a variety of free-radical frontal polymerization systems. It was observed that the microcapsules could be used successfully in number of systems, and comparisons were made with typical frontal polymerization systems. The effect of encapsulation of CHP on the pot life was tested in a variety of systems, and it was observed that systems containing microcapsules underwent a dramatic increase in pot life, from hours to weeks in certain systems and from a few days to several weeks in other systems. Polymer samples that were produced from 1,6-hexanediol diacrylate (HDDA) systems with and without microcapsules were tested for modulus and toughness. It was observed that the use of CHP microcapsules resulted in an increase in the modulus and toughness (up to 2x) of polymer samples.