Process for highly substituted carboxyalkyl celluloses and mixed ethers thereof

US4507474A · kind A · utility

Assignee

• Henkel Kommanditgesellschaft AUF · DE

Inventors

• Wilfried Raehse · Goldkronach, DE
• Norbert Kuehne · Haan, DE
• Willi Wuest · Ratingen, DE
• Konrad Engelskirchen · Meerbusch, DE

Key dates

• Filing date: Jan 24, 1984
• Grant date: Mar 26, 1985
• Expiry date: Jan 24, 2004

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08B11/12
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

A process for the production of carboxyalkyl celluloses having an average degree of substitution of at least 1.0. The process comprises up to 3 stages, but without any intermediate purification. The preferred suspension medium is isopropanol. In each stage of the process, the carboxyalkylating agent is used in quantities of less than 2.5 moles per mole of anhydroglucose unit and the alkylating agent in quantities of less than 5 moles per mole of anhydroglucose unit. The total water content of the system throughout the reaction as a whole must not exceed 450% by weight, based on the quantity by weight of cellulose used. Water contents of from 80 to 250% by weight are preferred.