Acrylonitrile (AN) was investigated as an important monomer for the graft copolymerization onto chitosan. A number of variables in the grafting reaction were investigated, including initiator and monomer concentration, duration, and temperature of the polymerization reaction. The graft copolymers were evaluated in terms of graft yield, grafting efficiency and % homopolymer. Moreover, modification of grafted chitosan was done by changing the nitrile group (-CN) to the amidoxime group (-C=NOH). Certain characterization for both the grafted Chitosan (Ch-g-PAN) and its amidoxime derivative -as compared to the parent polymer- are measured including the swell ability property, dye uptake, surface morphology, and metal uptake property. The results obtained reflect the feasibility for using Ch-g-PAN as absorbent for both Ni2+ and Co2+ ions. (C) 2009 Wiley Periodicals, Inc.J Appl Polym Sci 116: 413-421, 2010