Process for applying polymeric coatings, and resulting coated articles

Abstract

An improved process for coating an inert substrate, such as braided glass fiber sleeving and inert substrates of other materials and shapes, wiht a polymeric material such as a polyacrylate, a polyvinyl chloride, a silicone rubber, or a polyfluorocarbon, said method comprising the steps of: formulating an emulsion of the polymerizable material in water or other suitable polar phase; thickening the emulsion through the addition of an inert, finely-divided, particulate, hydrophilic inorganic oxide substance to a viscosity in the range of from about 35,000 to about 500,000 centipoises; applying the thicknened emulsion in the form of a uniform coating of desired thickness to the sleeving or other inert substrate; passing the coated substrate through a microwave energy chamber and subjecting the thickened emulsion coating to microwave energy of a frequency, at a power density, and for a peirod of time sufficient to substantially devolatilize, or dry and coalesce, said emulsion; and subjecting the devolatilized coating to thermal energy at a temperature and for a period of time sufficient to substantially complete polymerization. A braided glass fiber sleeve, or inert substrate of other configuration or material, containing a surface coating of a polymer, such as a polyacrylate, a polyvinyl chloride, a silicone rubber, or a fluoropolymer, such coating having substantially uniformly distributed therethrough very finely-divided particles of a chemically inert, hydrophilic, inorganic oxide, such as fumed silica, precipitated silica or aluminum oxide.