Vinyl Cellulose Copolymers

Abstract

Polyacrylonitrile-cotton copolymers were prepared by post-irradiation, simultaneous- irradiation, ceric ion, and ferrous ion/hydrogen peroxide-initiated graft copolymerization reactions. Molecular weights of the grafted polyacrylonitrile ranged from 33,000, when the simultaneous-irradiation method and dimethylformamide solvent were used, to 1,200,000 when the post-irradiation method and 75% aqueous zinc chloride solvent were used. The location of the grafted polyacrylonitrile ranged from principally the outer layers of the fibrous structure to uniform distribution within the structure. All of the textile properties of cotton yarns and fabrics, which had been graft-copolymerized with acrylonitrile, were apparently not wholly dependent on the molecular weight of the grafted polyacrylonitrile, the fraction of the cellulose molecules containing grafted polyacrylonitrile, or the distribution of the polymer within the fibrous structure. Of the properties evaluated, only the flat abrasion resistances of cotton fabrics, copolymerized with acrylonitrile using radiation methods and aqueous zinc chloride solvent, were significantly greater than those of copolymers prepared by other methods. The wrinkle recoveries of fabrics, containing the polyacrylonitrile which had the lowest molecular weight, were greater than those for fabrics grafted with polyacrylonitrile which had higher molecular weight. The relationships between the site on the cellulose molecule of the graft copolymerization reaction to the method of initiation and the properties of the cotton copolymers were considered.