Synthesis and characterization of a novel water-soluble mid-chain macrophotoinitiator of polyacrylamide by Ce(IV)/HNO3 redox system

A new water-soluble mid-chain macrophotoinitiator of polyacrylamide (PAAm) has been synthesized by redox polymerization. The polymerization of acrylamide (AAm) initiated by dihydroxy functional photoinitiator namely, 2-hydroxy-1-[4-(2-hydroxyethoxy)phenyl]-2-methyl propan-1-one (HE-HMPP), Irgacure 2959, in combination with cerium(IV) ammonium nitrate has been investigated in aqueous nitric acid. The effects of HE-HMPP, AAm, and Ce(IV) concentrations on the polymerization rate were investigated. The photodegradation and IR, 1H NMR, UV, and fluorescence spectroscopic studies revealed that polyacrylamide with desired photoinitiator functionality in the middle of the chain were obtained. This prepolymer was used in photoinduced free radical polymerization of methyl methacrylate (MMA) to produce PAAm–PMMA block copolymer.