Abstract
The graft copolymerization of gaseous monomers on polypropylene fibers has been carried out by a simultaneous irradiation technique. The fibers suspended in the middle of the ampoules were exposed to the vapor of vinyl chloride or vinylidene chloride, and irradiated by the γ-rays from 60Co. The vapor pressure of monomers was adjusted by changing the temperature of the liquid monomer. In the vinylidene chloride-grafting the rate of grafting was proportional to the vapor pressure of the monomer and also to the 0.73 th power of the dose rate. The rise in irradiation temperature brought about a marked decrease in the rate, the apparent activation energy o f the grafting being -8.0 kcal/mol. In the vinyl chloride-grafting, the rate of grafting was proportional to the vapor pressure, too, but proportional to the 1.1 th power of the dose rate. The apparent activation energy was almost null. A considerable homopolymer formation and fairly remarkable post-grafting were observed in both vinylidene chloride- and vinyl chloride-grafting.
