Quantitative Determination of BTCA Bound to Cellulosic Material by Means of Isocratic HPLC

Abstract

1,2,3,4-Butanetetracarboxylic acid (BTCA) offers an alternative to the conventional N- methylol compounds as a crosslinking agent for cellulosic textiles. Thus, it is of particular interest to determine the amount of BTCA that reacts with the cellulosic material. In this research, we saponify the cured fabric by means of a NaOH solution. The BTCA concen tration in the saponification mixture is measured with the aid of isocratic HPLC using the strong cationic exchange column Aminex HPX-87-H in combination with a uv detector. We study the effect of different concentrations of NaOH and find that there is a significant saponification reaction with NaOH concentrations greater than 0.05 M. Measurements of the dry crease recovery angle (DCRA) and IR transmission spectra indicate that the sapon ification reaction is complete. We test the analytical procedure by investigating three dif ferent fabrics impregnated with finish solutions containing 2, 4, 6, and 8% (w/w) BTCA and 6% (w/w) SHP (sodium hypophosphite). To verify the accuracy of the quantitative determination, we use calibration curve and standard additions methods. Recovery is 97.4 - 103.2% depending on the weight fraction of BTCA in the finish bath and on the fabric. Our statistics confirm that this procedure proves a precise and accurate analytical method for quantifying BTCA that has reacted with cellulosic fabrics.