Waterinsoluble fibres from cellulose acetate, cellulose propionate and cellulose butyrate with a very high absorption capacity for water and physiological fluids, and process for their preparation

摘要

Water-insoluble fibers made of cellulose acetate, cellulose propionate and cellulose butyrate with an extremely high absorption capacity for water and physiological liquids. The fibers have a) in the order mentioned a degree of esterification of 0.1 to 1.5, 0.1 to 0.95 and 0.15 to 0.8, b) an average degree of polymerization of 300 to 700, c) a fiber resistance in conditioned state from 6 to 20 cN / tex, d) a stretch in the conditioned state from 6 to 20%, e) a water retention capacity from 200 to 750% and f) a water absorption capacity of 8 to 18 cm³ / g fibers. The fibers which can be used in the fields of hygiene, household, clothing and technology are produced by a) preparing a solution of activated cellulose in dimethylacetamide or 1-methyl-2-pyrrolidone at a temperature of 20 to 80 ° C, the 5 to 13 Contains weight percent activated cellulose with an average degree of polymerization of 400 to 800 and 3 to 10 weight percent LiCl, b) the cellulose thus dissolved with the corresponding acid anhydrides in a molar ratio of 1: 0.5 to 1: 4 at 20 to 50 ° C in the presence of known esterification catalysts, up to the degrees of esterification mentioned in claims 1 and 2 and c) spinning the cellulose ester solutions thus obtained by wet spinning in a coagulant.