METHOD FOR PREPARING STABLY DISPERSED NONAQUEOUS MICROPARTICLE DISPERSIONS

摘要

A method for preparing polymer microparticles which are stably dispersed in a nonaqueous medium involves: (a) mixing into a nonaqueous medium a polymerizable component at least 20 percent of which is insoluble in the nonaqueous medium, said polymerizable component comprising at least one polymerizable species; (b) subjecting the mixture of (a) to stress sufficient to particulate the mixture; (c) polymerizing the polymerizable component within each particle under conditions sufficient to produce polymer microparticles stably dispersed in the nonaqueous medium, said polymer microparticles being insoluble in the nonaqueous medium and the nonaqueous medium being substantially free of dissolved polymer, said polymer microparticles further characterized in that less than 20 percent of the polymer microparticles have a mean diameter greater than 5 microns.