Studies on graft copolymerization of gellan gum with N,N-dimethylacrylamide by the redox system.

The present paper reports the graft copolymerization of N,N-dimethylacrylamide onto gellan gumby free radical polymerization using potassium peroxymonosulphate/sarbose redox system in an inert atmosphere. The reaction conditions for maximum grafting have been optimized by varying the reaction variables, including the concentration of N,N-dimethylacrylamide(4.0×10(-2)-20×10(-2) mol dm(-3)), potassium peroxymonosulphate (0.6×10(-2)-1.4×10(-2)mol dm(-3)), sarbose (0.4×10(-3)-3.6×10(-3) mol dm(-3)), sulphuric acid (2.0×10(-3)-10×10(-3) mol dm(-3)), gellan gum (0.6-1.4 g dm(-3)) along with time duration (60-180 min) and temperature (25-45°C).Water-swelling capacity, metal ion sorption and flocculation studies of synthesized graft copolymer have been performed with respect to the parent polymer. The graft copolymer has been characterized by FTIR spectroscopy and thermogravimetric analysis.