AbstractAcrylamide and acrylonitrile were polymerized with water‐soluble organic reducing compounds containing hydroxy groups such as methyl cellulose (MC), methyl hydroxy‐propyl cellulose (MHPC) and poly(ethylene glycol)s (PEG) in the presence of Ce(IV) in order to produce graft/block copolymers. The effect of cerium(IV) concentration, temperature, time and monomer concentration on the yield was studied. Copolymers of cellulose derivatives and polyacrylonitrile showed solubility properties similar to polyacrylonitrile. Both cellulose derivative‐polyacrylamide and poly(ethylene glycol)‐polyacrylamide copolymers were soluble i