Polymerization-Crosslinking of N-Methylolacrylamide in Cotton Fabric

Abstract

Several variations of polymerization-crosslinking of N-methylolacrylamide (NMA) in cotton were explored to clarify factors critical to achievement of resilience with superior retentions of strength and abrasion resistance in fabric. Per sulfate catalysis simultaneously initiated both polymerization and crosslinking reactions of NMA in cotton fabric; the results from dry-cure reactions fell in the conventional range of textile performance properties achieved by treatment of cotton fabric with agents such as dimethyloldihydroxyethyleneurea. Wet-cure reactions carried out in scaled bags at or above 100°C resulted in low resilience, high retentions of strength-abrasion resistance, and large increases in stiffness, the last attributed to fiber bonding in yarns. Wet-cure reactions conducted at or below 80°C caused little stiffness, and only in these cases was a subsequent catalyzed dry-cure reaction effective in raising resilience with good retentions of strength and abrasion resistance. Inclusion of alkali metal phosphates in the persulfate-initiated reaction of NMA with cotton in a pad-dry-cure caused retentions of abrasion resistance to be very substantially improved and retentions in breaking and tearing strengths to be significantly improved at durable-press appearance ratings of 4.5. These results are attributed to relatively sequential but rapid polymerization and crosslinking reactions, to reduction in formation of oxymethylene crosslinks, and possibly to reduced molccular degradation of the cellulose.