Synthesis, characterization, and applied properties of carboxymethyl cellulose and polyacrylamide graft copolymer

The synthesis of carboxymethylcellulose (CMC)-g-polyacrylamide (PAM) was carried out in an aqueous medium by using a redox system as an initiator. The effects of reactive conditions on the weigh-average molecular weight of the copolymers (such as initiator concentrations, monomer concentrations, initial reaction temperature, and pH value) were investigated, and the optimal conditions for the grafting reaction were established. The obtained graft copolymers were characterized by Fourier transform infrared spectroscopy, thermal analysis, X-ray diffractometry, intrinsic viscosity, and radius of gyration. An equation relating the radius of gyration of the copolymer influenced by the radius of gyration of PAM and CMC was obtained. The experimental results show how the salt-resistance and heat-resistance of graft copolymers are improved remarkably.