Biodegradable superabsorbent polymers (SAPs) were prepared by grafting acrylamide onto starches then crosslinking with N.N-methylene-bisacrylamide.This work focused on the effects of the amylose/amylopectin ratio of starches from the same source (corn) on the grafting reactions and performance of the resultant starch-based SAPs.To characterise each SAP, the acrylamide groups grafted onto the starch were detected by FTIR; grafting ratio and grafting efficiency were evaluated by a gravimetric method; and graft position and the length of the grafted segment were investigated by NMR.