2—THE HOMOGENEOUS ACID HYDROLYSIS OF METHYL CELLULOSE Part I—DETERMINATION OF REACTION RATE BY, REDUCING GROUP MEASUREMENTS

Publisher Website
Google Scholar
Abstract
The homogeneous hydrolysis of methyl cellulose in dilute hydrochloric acid has been followed by means of the change in end-group concentration measured by hypoiodite oxidation of the aldehyde groups. The reaction, which follows a unimolecular course in its early stages, was found to be a hydrogen-ion catalysis with an Arrhenius activation energy of 30,150 calories; the catalysis is of the type in which the reaction rate is determined by the decomposition of an intermediate complex formed by the transfer of a proton to a molecule of the cellulose ether prior to hydrolysis. There is an increase in specific reaction rate when the degree of degradation is large, due to the greater rate of hydrolysis of terminal glucose units; the methoxyl content also influences the reaction rate. In addition to those involved in 1 : 4 glucosidic bonds, there are a few combined aldehyde groups which are liberated very much more rapidly in acid solution; these weak bonds are not, however, main chain bonds.

This publication has 28 references indexed in Scilit: