METHOD OF CARBOXYMETHYLCELLULOSE PRODUCING Russian patent published in 2002 - IPC

FIELD: polymers. SUBSTANCE: invention relates to production of high-molecular compounds, namely, to methods of production of carboxymethylcellulose that can be used as semiproduct for production of purified water-soluble or water-swelling metal salts widely used as thickening agents, emulsifying agents, stabilizers of aqueous solutions, suspensions and emulsions of different assignment. Method of production involves conversion of carboxymethylcellulose sodium to acid form using ortho-phosphoric acid an aqueous solution with concentration 20-30% at 30-50 C for 15-30 min. Also, ortho-phosphoric acid an aqueous solution can contain sodium sulfate additionally in the amount 0.1-10% of mass solution. Invention provides producing decrease of impurities in the end product, enhanced degree of polymerization of carboxymethylcellulose and its quality, increased yield of product, ability to utilize nonspecial products of reaction. EFFECT: improved method of production. 2 cl, 1 tbl