FINE COMPOSITE PARTICLE AND PROCESS FOR PRODUCING THE SAME

摘要

Fine core/shell type composite particles which comprise fine inorganic nanometer-size particles as cores and a fluoropolymer comprising units derived from a fluoromonomer as shells; a process for producing the particles; and a use of the particles. The particles comprise fine inorganic nanometer-size particles whose surface has been coated with a fluoropolymer comprising units derived from a fluoromonomer, wherein the proportion of the fine inorganic particles is 1 to 90 wt.% and the fluoropolymer comprises units derived from a fluoromonomer having a polymerizable unsaturated group in which a carbon atom has a fluorine atom bonded thereto. The process, which is for producing the fine composite particles, comprises polymerizing the fluoromonomer by seed polymerization in a polymerization system comprising an aqueous medium and fine inorganic nanometer-size particles dispersed therein in the presence of a surfactant. A powder comprising the fine composite particles is useful as a filler for incorporation into thermoplastic polymers or thermosetting resins, and a thermoplastic polymer or thermosetting resin containing the fine composite particles is used as a molding material. A powder of the fine composite particles in which the content of fine inorganic particles is low can be used by itself as a molding material.