On the mechanism of thermo‐oxidative degradation of cellulose ethers

Abstract

Cellulose and alcohol ethers of aliphatic series, benzyl, allyl cellulose and other ethers containing labile hydrogen atoms were shown to undergo thermo‐oxidative degradation owing to the formation of peroxide in the ether groups and to their decomposition with the removal of the corresponding aldehydes, alcohols, alkylhydroperoxides, and other products and the break of the pyranose cycle. This has been established by the method of labeled atoms. It was also shown that the peroxide groups in ethers are partially transformed into the corresponding ester groups. The reaction of ethyl cellulose with oxygen was investigated in greater detail. Kinetic data on the formation of ether peroxides and of the products of their decomposition are given. Cellulose ethers and esters in whose ether and ester groups the labile hydrogen atoms are absent (tritylcellulose, pivalinates, benzoates, etc.) are much more resistant to thermo‐oxidative degradation.