Synthesis and characterization of κ-carrageenan/poly(N,N-diethylacrylamide) semi-interpenetrating polymer network hydrogels with rapid response to temperature

摘要

In this study, a novel classical thermo- and salt-sensitive semi-interpenetrating polymer network (semi-IPN) hydrogel composed of poly(N,N-diethylacrylamide) (PDEAm) and κ-carrageenan (KC) was synthesized by free radical polymerization. The structure of the hydrogels was studied by Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). FTIR and SEM revealed that the semi-IPN hydrogels possessed the structure of H-bonds and larger number of pores in the network. Compared to the PDEAm hydrogel, the prepared semi-IPN hydrogels exhibited a much faster response rate to temperature changes and had larger equilibrium swelling ratios at temperatures below the lower critical solution temperature (LCST). The salt-sensitive behavior of the semi-IPN hydrogels was dependent on the content of KC. In addition, during the reswelling process, semi-IPN hydrogels showed a non-sigmoidal swelling pattern.