Adsorption of Labeled Sodium Carboxyrnethyl Cellulose by Textile Fibers

Abstract

A carbon-14-labeled sodium carboxymethyl cellulose (CMC) has been employed to measure its adsorption by textile fibers, and in the case of cotton, to investigate the relationship between adsorption and detergency action. Adsorption of CMC by cotton was found to depend on the presence of excess cations in solution, increasing with cation concentration and valence. Equilibrium adsorption of CMC in the presence of excess cations was found to have a zero temperature coefficient. Variation of pH within the alkaline range had no significant effect. Limited measurements with fibers other than cotton indicated little or no adsorption by wool, Orlon,2 or acetate (in the presence of excess cations). There was significant adsorption by nylon and rayon, but this ad sorption was greatly reduced by addition of an alkylaryl sulfonate. Detergency evalua tions with the labeled CMC and with unlabeled material indicate that CMC adsorbed on cotton has a significant action in preventing redeposition of particulate soil materials. The adsorption and detergency data indicate that the quantity of CMC required to form a monomolecular layer on cotton fibers may be on the order of 400-500 micrograms per gram of cotton.