Evaluating ester crosslinking of cotton fabric by a polycarboxylic acid using acid-base titration

Polycarboxylic acids such as 1,2,3,4-butanetetracarboxylic acid (BTCA) have been the most promising nonformaldehyde durable press finishing agents to replace the traditional N-methylol reagents. High levels of smooth fabric a ppearance are the direct result of ester crosslinking of cotton cellulose b y a polycarboxylic acid, and appearance is therefore determined by the amou nt of ester crosslinks formed on the fabric. In this research, we use acid- base titration to evaluate ester crosslinking by measuring the concentratio ns of the eater and the free carboxylic acid and the percent of carboxyl gr oups forming crosslinks on the cotton treated with BTCA. We correlate the w rinkle resistance of the treated cotton with the eater concentration on the fabric. The linear correlation between wrinkle-recovery angle and ester co ncentration indicates that eater concentration determined by titration can be used as the basis for evaluating the effectiveness of crosslinking for d urable press finished cottons.