Studies on graft copolymerization of 2-acrylamidoglycolic acid on to partially carboxymethylated guar gum and physico-chemical properties

An unreported graft copolymer of 2-acrylamidoglycolic acid with partially carboxymethylated guar gum has been synthesized under nitrogen atmosphere using peroxymonosulphate/thiourea redox pair at 40 degrees C. The effect of reaction conditions on grafting parameters i.e., grafting ratio, efficiency, conversion, add on, homopolymer and rate of grafting has been studied. Experimental results show that maximum grafting has been obtained at 0.1 g dm(-3) concentration of partially carboxymethylated guar gum and 5.3 x 10(-2) mol dm(-3) concentration of 2-acrylamidoglycolic acid. It has been observed that grafting ratio, add on, conversion, efficiency and rate of grafting increase up to 5.0 x 10(-3) mol dm(-3) of hydrogen ion, 2.4 x 10(-3) mol dm(-3) of thiourea, 10 x 10(-3) mol dm(-3) of peroxymonosulphate and 40 degrees C of temperature. Grafted copolymer has been characterized by FTIR spectroscopy and thermogravimetric analysis. Physicochemical properties of partially carboxymethylated guar gum-g-2-acrylamidoglycolic acid have been determined. (C) 2010 Elsevier Ltd. All rights reserved.