Chain scission, degradation, cotton

Thermal Degradation. Thermal degradation follows different paths depending upon whether moisture and oxygen are present. Above 140 °C, however, moisture does not influence degradation. Continuous exposure to heat below the pyrolysis temperature can produce chain scission and autoxidation within the cellulose chains (23,24). To produce thermally degraded samples for evaluation, cotton fabrics were exposed in a forced convection oven at 168° 4°C. Fabric was removed at intervals ranging from 24r-211 hr for examination. 

Chain Scission and Degree of Degradation of Cotton Fiber After Milling in a Norton Ball Mill... 

Resins may influence phototendering of rayons. Wood (26) has reported that viscose rayon fabrics treated with urea formaldehyde or thiourea formaldehyde resin are protected from the degradative effects of mercury vapor lamp radiation. The mechanism of the protective effect is not fully understood as yet. Possibly resins can quench free radicals formed during irradiation. Work with resin-treated cotton indicates that simultaneous scission of cellulose chain molecules and resin-cellulose bonds occurs on exposure to light (63). 

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