GB486969A - Improvements in or relating to the production of cellulose ethers - Google Patents

Abstract

Mixed ethers of cellulose are obtained by reacting a partially alkylated cellulose, containing at least 0,5 molecular proportions of an alkyl group having less than 3 carbon atoms for each glucose unit of the cellulose, with an alkyl halide containing from 8 to 18 carbon atoms in the presence of an alkali. Cellulose may be subjected to partial etherification by reaction with ethyl or methyl chloride or sulphate, the cellulose being preferably in the form of alkali cellulose. Mixtures of alkyl halides corresponding to mixtures of alcohols produced from coconut oil by catalytic hydrogenation including the mixture of alcohols known under the Registered Trade Mark " Lorol," or mixtures of alkyl halides corresponding to the alcohols obtained by reduction of sperm oil acids, including the mixture of alcohols known as Stenol, may be employed as etherifying agent for the second stage. The reaction with higher aliphatic alkylating agent may be carried out at elevated temperatures. In an example alkali cellulose prepared in presence of a wetting agent is heated in two temperature stages with a mixture of ethyl chloride and "Lorol" chloride until a partially ethylated cellulose is produced. The reaction mass is then further heated at a higher temperature in order to effect reaction with the "Lorol" chloride. The product is precipitated and washed with acetone. In another example, alkali cellulose is heated with a mixture of ethyl chloride, octyl chloride, and kerosene in two stages. In other examples, the higher aliphatic chloride is added to the reaction mass after formation of methyl or ethyl cellulose, or the ethyl cellulose is isolated from the reaction mass and then treated with the higher aliphatic chloride and caustic soda. Bromides or iodides may be used instead of chlorides. Besides the alkyl halides from hydrogenated coconut oil or hydrogenated sperm oil, mixed alkyl halides corresponding to the alcohols obtained by reduction of the mixed acids resulting from the hydrolysis of other oils and fats may be used. The products are soluble in kerosene, hot paraffin, toluene, methanol, dioxane, or other solvent, depending on the proportion of higher and lower alkyl groups present. They may be used in the production of lacquers, and plastics.