THERMOANALYTICAL STUDY OF DURABLE PRESS REACTANT LEVELS ON COTTON FABRICS .1. NONFORMALDEHYDE POLYCARBOXYLIC ACIDS

A current goal of our research is to identify unknown durable press (D p) finishes on cotton fabrics using only thermal analytical techniques . In pursuit of this goal, we have treated 100% cotton printcloth with five low- and nonformaldehyde finishes at four to six treatment level s. Two polycarboxylic acids-citric and butanetetracarboxylic-were used with sodium hypophosphite catalyst to produce nonformaldehyde fabric finishes. Three formaldehyde-based finishes were produced with 1,3-dim ethylol-4,5-dihydroxyethyleneurea. Results of differential scanning ca lorimetric and thermogravimetric analyses were compared with those of untreated and catalyst-treated controls. The thermal parameters tested to recognize reactants included amount of residue, maximum rates of w eight loss, peak temperatures, and peak areas, along with various para meter ratios. There were progressive changes in all fabric thermograms as agent/catalyst levels increased. Even at the 2% agent lever, we co uld detect that fabric had been treated. It was also not difficult to distinguish between the low- and nonformaldehyde DP finishes. Thermal profiles of catalyst controls indicated that the catalyst was a substa ntial contributor to thermal parameters. This study has brought fabric finish identification using thermal analyses much closer to reality.