Quantitative Analysis of the Nonformaldehyde Durable Press Finish on Cotton Fabric: Acid-Base Titration and Infrared Spectroscopy

Abstract

Butanetetracarboxylic acid (BTCA) has been a promising nonformaldehyde durable press finish for cotton fabrics to replace N-methyol reagents. Acid-base titration and Fourier transform infrared (FT-IR) spectroscopy are applied as quantitative analytical techniques to determine the amount of BTCA applied to cotton fabric and the amount of ester formed on the fabric after a curing process. Acid-base equilibria of BTCA are discussed. We find that FT-IR spectroscopy is a reliable quantitative analytical technique for quantifying BTCA and its ester on cotton fabric when the calibration standards are established by acid-base titration. Calibration curves and regression equations are pre sented. To determine the amount of ester formed on the finished cotton fabric using FT-IR spectroscopy, it is necessary to use a sodium hydroxide solution to quantitatively convert carboxyl to carboxylate. The acid-base equilibria associated with this procedure are also discussed.