Efficient process for preparing an ester of a cellulose ether
US10196461B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 21, 2015 |
| Grant date | Feb 5, 2019 |
| Priority date | — |
| Expiry date | Oct 21, 2035 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC09D101/32
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A process for producing an esterified cellulose ether can be efficiently be produced by reacting a moist cellulose ether having a water content of at least 10 percent, based on the weight of the moist cellulose ether, with an aliphatic monocarboxylic acid anhydride, a dicarboxylic acid anhydride or a combination thereof. Further improvements in efficiency and reduction in process steps are achieved in a process for producing an esterified cellulose ether which comprises the steps of a) reacting cellulose with an alkaline material to produce alkali cellulose, b) reacting the produced alkali cellulose with one or more etherifying agents and washing the produced cellulose ether to obtain a moist cellulose ether having a water content of at least 10 weight percent, and c) reacting the moist cellulose ether with an aliphatic monocarboxylic acid anhydride and/or a dicarboxylic acid anhydride and with a depolymerizing agent.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.