Thermally induced release from polymeric microparticles with liquid core
Herein we demonstrate how the volatdity of a Liquid can be manipulated by enclosing microdroplets of the Liquid into thin polymeric sheds. In this way, composite core-shed microparticles consisting of 80 wt% of a Liquid core material and 20 wt% of a polymer can be made 150 degrees C more stable than the individual core component. The thermal stability of the composite microparticles is found to be determined by the boding point of the core material and the average particle size, while the role of the particle shed thickness is much Less relevant. Two mechanisms responsible for the release of the core material from the microparticles at elevated temperatures were resolved: (1) thermally induced degradation of the shed and (2) diffusion of the core material through the polymeric shed boosted by the increased inner pressure.