Studies on Graft Copolymerization of N‐Vinyl‐2‐pyrrolidone on to Carboxymethylcellulose (Sodium Salt) and Metal Ion Sorption Behavior

Abstract

An unreported graft copolymer of N‐vinyl‐2‐pyrrolidone (N‐VP) with sodium carboxymethylcellulose has been synthesized under nitrogen atmosphere using peroxymonosulphate/thiourea redox pair at 40°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 0.4 g dm−3 concentration of sodium carboxymethylcellulose and 10×10−2 mol dm−3 concentration of N‐vinyl‐2‐pyrrolidone. It has been observed that grafting ratio, add on, conversion, efficiency and rate of grafting increase up to 6.0×10−3 mol dm−3 of hydrogen ion, 2.84×10−3 mol dm−3 of thiourea, 5.0×10−3 mol dm−3 of peroxymonosulphate and 45°C of temperature after that decrease. Grafted and ungrafted gum has been characterized by FTIR spectroscopy and thermogravimetric analysis. Water swelling and metal ion sorption behavior of sodium carboxymethylcellulose and sodium carboxymethycellulose‐g‐N‐vinyl‐2‐pyrrolidone have been determined. A probable mechanism has been suggested for graft copolymerization. It has been observed that the graft copolymer is thermally more stable than the parent polymer.