Composite Particles From Pickering-Stabilized Radical Mediated Thiol-Ene Suspension Polymerizations

摘要

Pickering stabilization is a facile method to create composite colloidal particles. Inorganic colloidal SiO2 nanoparticles are often used as the stabilizer for particles instead of the more common amphiphilic surfactants. Here the use of this approach in radical-mediated thiol-ene suspension polymerizations using monomers 1,3,5-triallyl-1,3,5-triazine-2,4,6(1H,3H,5H)-trione (TTT) and pentaerythritol tetrakis (3-mercaptopropionate) (PETMP) is described. The resulting micron-sized crosslinked poly(thioether) colloidal particles are coated with 80 nm silica nanoparticles. The addition of a small amount of various costabilizers is examined (hexadecane, cetyl alcohol and toluene), and while all yielded particles, cetyl alcohol provide more consistent results. Scanning electron microscopy and thermal analysis of the composite particles demonstrate morphologies that are consistent with a raspberry-like structure. No significant changes to the glass transition temperature are observed, which is consistent with the silica nanoparticles being located at the surface of the polymer particles.