The Radiation Grafting of Silicone onto Vinylon and Tetoron

Abstract

The radiation grafting of silicone onto Vinylon or Tetoron was carried out in air at room temperature, and the water repellency of silicone-grafted samples was measured by the spray rating test with the following results: 1) The rate of grafting of Vinylon is 0.91%/h. The grafting is accelerated markedly by heating after irradiation. It is concluded that most of the grafting of this system is based on the radicals formed by the thermal decomposition of peroxide. 2) On the silicone-Tetoron system, grafting proceeds rapidly by irradiation above 3 Mrad while little grafting occurs below 3 Mrad. The degree of grafting in air is equal to that in N2. Consequently, the grafting in this system is the result of direct reaction of radicals formed during irradiation. 3) The silicone-graft-Vinylon and -Tetoron possess water repellency that is highly durable to dry cleaning and abrasion. The water repellency of grafted Vinylon increases with increasing irradiation dosage, but that of grafted Tetoron becomes constant at about 1 Mrad. Tetoron is better than that of Vinylon with regard to water repellency.