Chemical Modification of Starch <i>via</i> Reaction with Acrylamide

Abstract

Abstract Reaction of starch with acrylamide was carried out under different conditions including reaction medium, catalyst, acrylamide concentration, reaction time and temperature as well as liquor ratio. Organic solvents, namely, isopropyl alcohol, dimethylformamide and cyclohexane alone and in admixture with water at different ratios were used as reaction medium. Catalysts used include sodium hydroxide, trisodium phosphate, sodium carbonate, sodium benzoate, sodium acetate and sodium formate. Acrylamide concentration ranged from 25% to 200%, based on weight of starch. The reaction was studied over a wide range of temperature and duration. Results obtained showed that the extent of reaction of starch with acrylamide is governed by each of these factors. Furthermore, this reaction yields mixed starch ethers, namely carbamoylethyl starch and carboxyethyl starch. Solubility, viscosity and moisture content of these starch ethers are determined by the sum of the amide and carboxyl contents.