Ceric ammonium nitrate induced grafting of polyacrylamide onto carboxymethyl chitosan

O-Carboxymethyl chitosan (CMCH) was prepared and characterized by FTIR spectroscopy and X-ray diffraction. Grafting of acrylamide (Am) onto CMCH using ceric ammonium nitrate (CAN) as an initiator was carried out under nitrogen atmosphere in aqueous solution. Evidence of grafting was confirmed by comparison of FTIR spectra of CMCH and the grafted copolymer as well as scanning electron micrography (SEM) and X-ray diffraction of the products. The effects of concentration of CAN, Am, reaction time and temperature on graft copolymerization were studied by determining the grafting percentage, grafting efficiency and percentage add-on. With other conditions kept constant, the optimum grafting conditions were obtained as follows: CMCH = 2 g, CAN = 0.2 M, and Am = 0.563 mol/L, reaction temperature = 40 degrees C, and reaction time = 4.5 h. (c) 2006 Elsevier Ltd. All rights reserved.