Chemical and Physical Properties of Cotton Modified by N-Methylol Agents

Abstract

The resistance to acidic hydrolysis of a large number of cellulose derivatives of mono- or polyfunctional N-methylol type agents, prepared under standardized pad-dry-cure conditions, is determined primarily by chemical factors, i.e., electronic effects of substituent groups on the intermediate carbonium-immonium ion. Agents used included formalde hyde and/or glyoxal adducts of ureas, melamines, carbamates, formamides, acetamides, hydrazides, pyrrolidones, and similar amides. Based on these and related experiments, it was concluded that most N-methylol and similar type agents reacted with cotton with little or no modification of their structure during the curing operation. Also, other reaction paths, which represent rearrangement, fragmentation (other than release of formaldehyde), or polymerization reactions, wetre generally limited. Further, crosslinking of cotton by formaldehyde was suppressed by the presence of amide type compounds and especially by the presence of reactive N-methylol agents. Numerous examples are provided to sub stantiate these general conclusions, to suggest limitations to these conclusions, and to show that chemical properties rather than physical properties determine the relative extent to which this type of finish is hydrolyzed.