GB231802A - A process for making cellulose combinations - Google Patents

Abstract

Cellulose derivatives are prepared by reacting with ammonia on a cellulose xanthofatty acid or a salt of such acid, that is, on such products as are obtained when a monohalogen fatty acid or a salt or derivative of such acid reacts on a cellulose xanthic acid or a cellulose xanthate, for instance, as described in Specification 231,800, and particularly when the halogen fatty acid is monochloracetic acid, a -bromopropionic acid, a -bromobutyric acid or bromosuccinic acid. The reactions between the halogen fatty acid &c. and the cellulose xanthic acid &c., and between the resulting cellulose xanthofatty acid &c. and ammonia may be carried out as separate processes, or they may be combined in one operation, that is, the ammonia may be added to the cellulose xanthofatty acid or alternatively to the cellulose xanthic acid either before, during or after the addition of the halogen fatty acid. The treatment of the cellulose xanthofatty acid with ammonia may be carried out in neutral, alkaline or acid solution; the cellulose xanthofatty acid may be in solution, in the solid state, or in suspension, for instance, in alcohol; the ammonia may be used as a gas or in solution, and in excess or in amount equal to or less than the theoretical quantity; and the reaction may be carried out at normal temperature, or with heating. The products are insoluble in water but soluble in aqueous alkalies, and are precipitated from their solutions by the addition of substances that neutralize ammonia, such as acids or salts, or by dehydrating agents; when precipitated in the form of threads or films, the products are strong, flexible and transparent.