We report a novel approach to prepare microparticles via a dispersion polymerization using the amine-catalyzed addition of a trithiol to a triacrylate. Microparticles loaded with various core materials were produced and applied in various systems to improve the desired characteristics of the given system. We determined that this type of microparticle could be used as either a stimulated release or controlled release system for certain desired core materials. These microparticles were able to prevent the interaction between a Lewis acid initiator and fumed silica, improving the rheological properties of an epoxy system containing the initiator. (C) 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 50: 409-422, 2012