Supercontracting and Setting Behavior of Modified Wool Fibers

Abstract

Ultraviolet irradiation of wool fibers increases their rates of supercontraction in unbuffered LiBr solutions and of setting in boiling water. There is a second, slower effect of ultraviolet shown by a progressive reduction in degree of contraction at equi librium. Treatment with thioglycollic acid or peracetic acid also increases the rates of supercontraction and setting. Iodination or reaction with the Van Slyke reagent reduces the rates. There is little or no loss of tyrosine. and little loss of cystine in the irradiation time which gives the maximum effect on rate of supercontraction. Rate of supercontrac tion, rate of setting, and second-order transition temperature are closely related properties, as are equilibrium contraction, maximum set, and remanent stress.