Synthesis of Electric-Responsive Hydrogel with Semi-Interpenetrating Network and Its Performance in Forward Osmosis Desalination

In order to improve the performance of hydrogel- driven forward osmosis (FO) desalination, electric- responsive hydrogel poly(2- acrylamido- 2- methyl- l- propanesulfonic acid- co- acrylamide)/ sodium carboxymethyl cellulose (P(AMPS- AM)/CMC) with semi- interpenetrating network was prepared by the interpenetrating polymer network (IPN) technology and used as novel draw agent. The chemical structure and morphology of the hydrogel were investigated by Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscope (SEM). The swelling behavior and electro- responsive nature of the hydrogel were investigated. The performance of the hydrogel in the FO desalination process was also explored. Results show that the hydrogel exhibits a porous structure, and the swelling behavior follows the second-order swelling kinetic model with a theoretical equilibrium swelling capacity of 181.5 g/g. The hydrogel shows a significant deswelling behavior under the electric stimuli of 15 V. In FO test, in comparison with P(AMPS- AM) without CMC modification, the P(AMPS- AM)/CMC achieves a similar initial water flux but its water recovery rate under the electric stimuli of 15 V is 1.9 times higher than that of the former, and the water recovery rate is only reduced by 7.97% after three cycles of continuous regeneration. Besides, the P(AMPS- AM)/CMC can not only obtain a higher water flux but also have a certain advantage in water recovery compared with the reported hydrogel draw agents. © 2022, Editorial Board of Polymer Materials Science & Engineering. All right reserved.