GB718188A - Improvements in wood pulp and method of producing same - Google Patents

Abstract

A mixed ether which contains a polyethylene oxide radical and an aliphatic hydrocarbon radical containing more than seven carbon atoms, and which is preferably water-soluble but at least slightly water-soluble, is added to wood pulp, prior to the completion of drying, in a proportion of 0.015 to 0.5 per cent. by weight based on the bone dry weight of the pulp. The addition prevents inactivation in non-aqueous conversion processes, e.g. the production of cellulose acetate, and in aqueous conversion processes, e.g. the viscose process. The preferred mixed ethers contain 8 to 50 ethenoxy groups and a normal primary aliphatic hydrocarbon radical of 8-20 carbon atoms. They may be prepared by conventional processes from fatty alcohols and ethylene oxide using sodium as a catalyst. The fatty alcohols may be synthetic or may be prepared by catalytic hydrogenation of vegetable or animal oils. Pure or technical fatty alcohols may be used. It is preferred to incorporate the mixed ethers in the refined wood pulp on the sheet-forming machine prior to drying by means of sprays or rotating rolls, so that the mixed ethers are incorporated on one or both surfaces of the sheet. Tests are reported giving the effect of the addition of compounds such as the dodeca-ethenoxy ether of lauryl alcohol and the nonadeca-ethenoxy ether of oleyl alcohol to wood pulp intended for use in acetylation and xanthation processes. Specifications 601,783 and 685,843 are referred to.