PORE STRUCTURE OF COTTON FABRICS CROSS-LINKED WITH FORMALDEHYDE-FREE REAGENTS

Pore structures of cotton fabric crosslinked with several formaldehyde-free durable press reagents are elucidated, and results are compared with those for the industry standard, DMDHEU (dimethyloldihydroxyethyleneurea). The formaldehyde-free reagents were BTCA (butanetetracarboxylic acid), DHDMI (dihydroxydimethylimidazolidinone), and the glyoxal/glycol system; the fabric was an 80 x 80 cotton print-cloth. Treatments were designed to impart the same degree of conditioned wrinkle recovery (WRA) to the fabric. A reverse gel permeation chromatographic technique was used to follow changes in pore size distribution. Columns were prepared by settling water slurries of the ground cotton in a conventional manner. Two series of water soluble solutes, which were series of oligomeric sugars and ethylene glycols, were used to study the elution characteristics of the unmodified and crosslinked samples. Internal structure differences were also elucidated by means of moisture regain, considered to be a measure of the internal surface of the cotton fiber in the conditioned state, and water of imbibition, a measure of internal volume in the water-swollen state. Formaldehyde-free crosslinking reagents effect a lower level of collapse of the internal pore structure of the cotton fiber than does DMDHEU at generally comparable levels of resilience.