The Radiation Grafting of Silicone onto Rayon and Acetate

Abstract

The method of radiation grafting of silicone onto cotton was applied to rayon and acetate with the following results : 1) Although, as known, grafting usually occurs at the noncrystalline region of the polymer, both the rate of grafting and the crystallinity of cotton are greater than those of rayon. Therefore, in this system the grafting does not depend only on crystallinity. 2) The rate of grafting on rayon is less than on acetate. The concentration of peroxide formed by 1.9 Mrad of γ-irradiation is 0.52 X 10-2 mol/l in rayon and 1.30 X 10-2 mol/l in acetate. The radiation sensitivity is increased by the acetylation of. OH-groups in cellulose. It is concluded that the grafting of this system depends on the number of radicals formed. 3) The water repellency properties of silicone-graft-rayon-and-acetate show that the structure of the grafted silicone on the surface of the base polymer by irradiation differs from that of the coated silicone prepared by heating in the presence of a catalyst.