Effect of γ-Irradiation of Cellulose on the Molecular-Weight Characteristics of Nitro Esters Produced from It

Resumo

The effect of γ-irradiation of cotton cellulose on the molecular-weight distribution (MWD) of the nitro esters prepared from the irradiated cellulose has been studied. It has been established that the degradation of cellulose during the sulfuric acid–free nitration in fuming nitric acid occurs according to a random law with the most probable MWD, whereas the esters obtained in a sulfuric acid–nitric acid nitration mixture are almost uniform in terms of MWD. The rate constants of degradation by nitration increase with the absorbed dose. An increase in the uniformity of the nitro esters as a result of the washing out of the low-molecular-weight fraction improves their physicomechanical characteristics. An equation is proposed for describing the kinetics of degradation of irradiated cotton cellulose during its nitration in fuming nitric acid.