GAS-PHASE GRAFT-POLYMERIZATION IN POLYPRO PYLENE FIBERS WITH NONUNIFORM DISTRIBUTION OF THE GRAFTED POLYMER

Diffusion coefficients, Henry constants, sorption heats, rates and hea ts of graft postradiational polymerization are measured and compared f or methyl methacrylate, acrylic acid, acrylonitrile, vinyl acetate, vi nylidene chloride, and styrene in polypropylene fibers. It is shown th at under the conditions, when the polymerization rate is comparable wi th the rate of sorption of monomers into the initial fiber and, conseq uently, according to the commonly accepted view, instead of grafting p roceeding uniformly throughout the fiber, as expected, a nonuniform (s urface) grafting regime occurs in the cases of methyl methacrylate, ac rylic acid, vinyl acetate, and styrene.