Thermoanalytical Study of Durable Press Reactant Levels on Cotton Fabrics

Abstract

Cotton printcloth has been treated with five low- and nonformaldehyde finishes at multiple treatment levels. In Part I, two polycarboxylic acids, butanetetracarboxylic and citric, catalyzed with sodium hypophosphite produced the nonformaldehyde fabric finishes. Three formaldehyde-based finishes have been produced with 1,3-dimethylol- 4,5-dihydroxyethyleneurea (DMDHEU) catalyzed with magnesium chloride / citric acid and are the subject of Part II. Differential scanning calorimetric and thermogravimetric analyses are performed and the results compared with those of untreated and treated controls. Thermal parameters and various parameter ratios are analyzed for progressive changes as agent / catalyst levels increase. Thermal profiles of catalyst controls indicate that the catalyst is a substantial contributor to thermal parameters. We can distinguish between the low and nonformaldehyde DP finishes, between the three DMDHEU-based finishes, and between the four finish levels. Finish level is the most difficult. Three- dimensional comparison graphs of three parameters chosen by means of stepwise discriminate analyses allow finish level assessments to within 2%. The preponderance of evidence after parameter-by-parameter comparisons correctly assigns finish level. A current goal of our research is to identify unknown durable press finishes on cotton fabrics using only thermal analytical techniques. Quality control applications relative to finish and finish level are clearly possible at this time. This study has brought us much closer to realizing our primary goal of finish identification using only ther moanalytical procedures.