Influence of Atmospheric Oxidation on Supercontraction of Wool Fibres reduced with Thioglycollic Acid

Abstract

THE rate of supercontraction of a keratin fibre is progressively enhanced by chemical treatment which results in the breakdown of the disulphide cross-linkages in the fibre. The maximum supercontraction value is, however, not greatly affected by such treatment¹. Fibres, in which the disulphide cross-linkages have been reduced with thioglycollic acid, contain a high percentage of sulphydryl groups². These sulphydryl groups tend to undergo atmospheric oxidation, which causes the formation of new —S—S— cross-linkages³, a reaction which can be prevented by blocking the reactive —SH groups. The question arises as to what the effect of such oxidative changes will be on the Supercontraction of reduced fibres.