Synthesis and characterization of sodium alginate/acrylamide semi‐interpenetrating polymer networks

Sodium alginate (NaAlg)/acrylamide (AAm) semi‐interpenetrating polymer networks (IPNs) were prepared with three different compositions, in which the NaAlg concentration was 1, 2, or 3% (w/v) in 50% (w/v) AAm solutions. These solutions were irradiated with a 60Co γ source at different doses. The conversion percentage was determined as follows. The NaAlg/AAm IPN hydrogels were immersed to swell in a solution of the desired pH (3–9) at 25°C. The swelling results at pHs 7.0 and 9.0 indicated that the NaAlg/AAm IPN hydrogel containing 3% NaAlg showed the maximum swelling percentage in water. The diffusion of water within the NaAlg/AAm IPN hydrogels was non‐Fickian in character. The diffusion coefficients of the NaAlg/AAm IPN hydrogels in water were calculated. The thermal properties of NaAlg, polyacrylamide, and NaAlg/AAm IPNs were determined.