METHOD FOR PREPARING CARBOXYMETHYL STARCH SODIUM SALT Russian patent published in 2008 - IPC C08B31/00 C09J103/08 C09K8/03 

FIELD: chemical technology.

SUBSTANCE: invention relates to a method for synthesis of carboxymethyl starch sodium salt used as a thickening agent and emulsifier in paper and textile industry, as component of drilling solutions in oil and gas extracting industry. Carboxymethyl starch sodium salt is prepared by treatment of starch with a carboxymethylating agent, addition of special additives, treatment with sodium hydroxide aqueous solution in reactor-mixing machine in three working zones, not less, at the filling coefficient of working zones 0.5-0.8 and the shift rate 500-1500 s^-1 followed by drying. Invention provides increasing degree of substitution in carboxymethyl starch sodium salt and water loss index in using as a component of drilling solutions.

EFFECT: improved preparing method.

5 cl, 1 tbl, 1 dwg, 4 ex