GB458597A - Improvements in the manufacture of derivatives of polyhydroxy compounds - Google Patents

Abstract

Fibrous cellulosic materials are etherified under substantially anhydrous conditions in the presence of organic bases, by means of compounds of the general formula RX or R2SO4 as the sole etherifying agents, where X is a halogen atom and R is an alkyl or aralkyl hydrocarbon radicle or a carboxy or esterified carboxy substitution derivative thereof. Suitable etherifying agents are dimethyl and diethyl sulphates, methyl and ethyl chlorides, benzyl chloride, chloracetic acid, bromacetic acid, ethyl chloracetate, and ethyl bromacetate. As organic bases, methylamine, ethylamine, pyridine, piperidine, aniline, and methyl anilines are particularly useful. The etherification is preferably carried out in the presence of a water-immiscible diluent. In an example, cellulose is soaked in diethylamine, pressed, and introduced into an autoclave together with benzene and diethyl sulphate. In a second example, cellulose is treated in an autoclave with ethyl chloride in the presence of pyridine and ether. The products are suitable for conversion to other derivatives of cellulose, as is described in Specification 458,596. According to the Provisional Specification, the process is applicable to the etherification of other polymeric hydroxy compounds, e.g. polymerized vinyl alcohol and starch. Specifications 207,562, 249,173, 263,938, [all in Class 2 (ii)], and 414,751, [Group VIII], also are referred to.