Fibers disulfide bond rupture

J. B. Speakman (1936a) attributes the optimum pH of 9-10 for setting in water to the need for hydrolytic rupture of disulfide bonds. Treatment of wool with nitrous acid (Speakman, 1936a), adsorption of anions (Elliott and Speakman, 1943), the sulfation of the fiber (Speakman and Elliott,... 

Farnworth (1957, 1960) showed that chemical treatments which rupture disulfide bonds, such as reduction followed by methylation or treatment with sodium bisulfite solutions, increase the rate of setting in boiling water and decrease the temperature required to give a predetermined set in a fixed time. Set fibers contract in boiling formic acid or 1M LiBr to lengths less than their original length (Table XXVII). Farnworth con-... 

The magnitude of the changes in longitudinal and torsional stiffness of wool caused by rupturing disulfide bonds is very dependent on the relative humidity used for stressing the fibers. In dry fibers the effects of disulfide rupture are small or not apparent (Harris and Brown, 1946 Feughelman, 1963 Feughelman and Mitchell, 1964). 

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