METHOD OF LOWERING MOLECULAR WEIGHT OF CELLULOSE DERIVATIVE AND METHOD OF ETHERIFYING LOW-MOLECULAR WEIGHT CELLULOSE DERIVATIVE

摘要

PURPOSE: To enable a cellulose derivative to be etherified at a high concentration of reaction sites and a high efficiency of the reaction of an etherifying agent by heating a specific cellulose derivative in an organic solvent in the presence of a water-soluble oxidizing agent and water. ;CONSTITUTION: A cellulose derivative is heated at 10-90°C in an organic solvent in the presence of a water-soluble oxidizing agent and water to lower its mol.wt. The derivative is at least one member selected from among carboxymethyl cellulose, methyl cellulose, ethyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, and lowly substituted benzyl cellulose and has an equilibrium moisture absorption of 10% or higher as measured after 24-hour standing at 80% RH and 20°C. A 5% aqueous solution of the derivative has a viscosity of 5,000cP or higher.;COPYRIGHT: (C)1994,JPO&Japio