Differentiation of Catalyst Types in the Formaldehyde-Cotton Cellulose Reaction1

Differences in effectiveness between a Bronsted acid catalyst (hydroxymethane sulfonic acid) and two commonly employed Lewis acid catalysts (Zn(NO3)2 and MgCl2) on the pad-cure reaction of formaldehyde with cotton cellulose were determined in statistical experimental designs. The effects of each catalyst were followed by measured textile properties. Two methods for comparison of properties, one based on equal durable press appearance and a second based on equal conditioned wrinkle recovery angles, indicated that cotton reacted with formaldehyde in the presence of the Bronsted acid catalyst generally had superior resilience properties. Cotton reacted in the presence of the Lewis acid catalysts had better strength retentions at equivalent resilience by either method of comparison, and better abrasion properties by the method based on durable press appearance. Cotton reacted with formaldehyde and Lewis acid catalysts to a durable press appearance rating of 4.0-4.3 had better strength, abrasion, and wrinkle recovery angles than cottons reacted with formaldehyde in the presence of the Bronsted acid.