HYDROXYALKYL METHYLCELLULOSE HAVING SOLUBILITY AND THERMOREVERSIBLE GELATION PROPERTIES IMPROVED

摘要

A hydroxyalkyl methylcellulose having the improved solubility and thermoreversible gelation properties is provided to control the projection order or speed of the esterification agent so that the substitution of a methoxyl group is performed. In the water soluble hydroxyalkyl methylcellulose, the hydroxyalkyl group has the substitution mole number of 0.05 to 01 and the methoxyl group has the substitution degree of 1.6 to 1.9. The hydroxyalkyl group is divided into the substituted hydroxyalkyl group and non-substituted hydroxyalkyl group. The hydroxyl group of the hydroxyalkyl group is additionally substituted with the methoxyl group. The ratio of the mole fraction of the non-substituted hydroxyalkyl group to the substituted hydroxyalkyl group is above 0.4. The hydroxyalkyl group is the hydroxypropoxyl group or the hydroxyethoxyl group. The hydroxyalkyl methylcellulose is obtained by adding the hydroxyalkyl esterification agent and methyl etherication agent.