GB191316905A - Process for the Manufacture of Acid Esters of Cellulose, Soluble in Acetone. - Google Patents

Abstract

16,905. Knoll & Co. Aug. 1, 1912, [Convention date]. Carboxylates. - Acidyl-celluloses soluble in acetone are prepared by heating the corresponding insoluble esters with glacial acetic acid and in the absence of acetic anhydride or water. Catalysts may be present, and it is preferred to carry out the process in the presence of suitable organic materials, such as aloohol, glycerine, acetines, and oxy-acid esters', and these added substances may serve as filling materials for the product. When starting with the primary acidylating-solutions containing acetic anhydride, the latter is removed according to the present process by the addition of a suitable substance other than water, such as alcohol or glycerine. In examples, the finished acetate is heated with glacial acetic acid, with or without the addition of methylamine sulphate, or alcohol or monacetine ; the primary acetylating-solution containing a mildly-acting catalyst, such as a mixture of methylamine bisulphate and sulphate, or the latter alone, or sodium ethyl sulphate is heated after the addition of alcohol or glycerine; the primary acetylating prepared with the aid' of sulphuric acid as catalyst is treated with potassium acetate, and heated after the addition of alcohol or glycerine. Specifications 2491/13 and 4353/13 are referred to.