Colloid-Chemical Basis for the Action of the Coagulating Bath upon Viscose

Abstract

In an effort to interpret the phenomena which occur when viscose solution is extruded into the spinning bath, as in the viscose rayon process, the stability of cellulose xanthate sol in the presence of electrolytes has been studied. Coagulation values for various salts and mixtures of salts on cellulose xanthate are reported. From these values a classification of ions according to their coagulating power and mechanism of coagulation has been suggested. In similar fashion, the behavior of salt mixtures on cellulose xanthate sol has been classified as additive, sensitizing, or antagonistic in accordance with colloid-chemical theory. The rate of coagulation by different ions and the influence of the degree of sulfidity and the degree of polymerization of the cellulose xanthate on the coagulation values are discussed. These data can be corre lated with changes which take place in the course of fiber formation during viscose rayon spinning.