| abstract |
PURPOSE: To make particulates spherical and improve, for example, the uniformity of the particle size and the heat resistance by hydrolyzing polymer particulates obtained from a vinyl monomer having a hydrolyzable silyl group and a copolymerizable vinyl monomer, thereby allowing them to crosslink. n CONSTITUTION: A comonomer mixture of 0.01-30mol% vinyl monomer having a hydrolyzable silyl group (e.g., γ-methacryloxypropyltrimethoxysilane) and other vinyl monomer copolymerizable therewith (e.g., styrene) is polymerized in a solvent wherein the comonomer mixture is soluble, but the copolymer that will be produced therefrom is insoluble (e.g., ethanol) in the presence of an oil-soluble initiator and a dispersion stabilizer at 50-80°C, thereby producing polymer particulates. Then, the silyl groups present in the particulates are hydrolyzed with an acid or an alkali, thereby allowing them to crosslink. n COPYRIGHT: (C)1990,JPO&Japio |