AQUEOUS ALCOHOLIC ALKALINE PROCESS FOR CATIONIZATION AND ANIONIZATION OF STARCH

摘要

A starch cationization process comprises suspending the starch in an aqueous alcoholic alkaline solvent containing a critical level of water (starch to water ratio 1:3 to 3:1), heating the reaction mixture for a few minutes at 30-90 DEG C, adding a cationizing reagent such as 3-chloro-2-hydroxypropyl-trimethylammonium chloride, heating for 1-24 hours at 30-80 DEG C, neutralizing, centrifuging, washing and drying of the cake to yield cationic starches with degrees of substitution of 0.01 to 0.12. Amphoteric starches are produced by simultaneous or sequential reaction of an anionic reagent with or after the cationic reagent in the aqueous alcoholic alkaline solvent. Solvent recovery and concentration of effluent solids is facilitated by distillation.