Modification of Wool in Dimethyiforpiamide with Mono- and Diisocyanates

Abstract

By virtue of hot dimethylformamide as a medium, wool has been chemically modified with organic isocyanates. Fabrics have been treated with 19 aromatic and aliphatic monoisocyanates, 6 diisocyanates, and 1 polyisocyanate. With phenyl isocyanate as a model compound, the reaction is most rapid when the mole-ratio of isocyanate to dimethylformamide is about 1 to 2. With p-bromophenyl isocyanate, an uptake (weight increase) of 71% of the weight of the wool has been achieved. Most of the treatments. particularly with diisocyanates, considerably increase chemical resistance. The modified fabrics are also more resistant to laundering shrinkage; however, their physical properties are usually poorer than those of the untreated fabric.