Abstract: This disclosure relates to the production of methyl hydroxypropyl cellulose ethers having a degree of molar substitution (M.S.) of greater than 2. The methyl hydroxypropyl cellulose ethers are prepared at low cost under mild conditions and are particularly useful in gelling organic solvents having a solubility parameter of 8 - 16. They also have compatibility for mixtures of organic solvents and water and are helpful in gelling such solutions when the percentage of water in such mixtures is up to about 60%.

Abstract: This disclosure involves the acetate ester of methyl hydroxypropyl cellulose. This particular cellulose ester is useful as a gelling agent for organic solvents. The methyl hydroxypropyl cellulose acetate is prepared by the simultaneous hydroxypropylation and methylation of cellulose and by the continuation of the cellulose derivatization into acetylation. The overlapping relationship of the hydroxypropylation and acetylation processes is found to be efficient and economical in that it eliminates the difficulty of isolation and recovery of the water insoluble methyl hydroxypropyl cellulose.