为降低正渗透(FO)汲取剂的再生能耗，制备了具有电场敏感性的聚(N,N-二甲基丙烯酰胺-co-2-丙烯酰胺基-2-甲基丙磺酸) (P(DMAM-co-AMPS))水凝胶汲取剂。对该水凝胶的化学结构、形貌、溶胀性、机械性能、含水状态以及电场敏感性进行了表征，并考察了其在FO过程中的水通量和再生性能。结果表明，所制备水凝胶平衡溶胀度为532 g/g，且溶胀过程符合Fickian型扩散规律。在外加接触电场刺激下，凝胶表现出明显、可逆的消溶胀性。以2 g/L NaCl为原料液，该凝胶在初始1h FO脱盐过程中的平均水通量为1.81 L m-2 h-1，24 h结束后将其置于15 V电压下脱水40min，可获得67.7%的水回收率，具有一定的应用潜力。

Electric-sensitive poly(N,N-dimethylacrylamide-co-2-acrylamido-2- methyl-l-propanesulfonic acid) (P(DMAM-co-AMPS)) hydrogels were prepared and explored as draw agents in order to reduce the energy consumption of draw agent regeneration in forward osmosis (FO). The chemical structure, morphology, swelling behavior, mechanical property, water state and electrical sensitivity of the hydrogels were characterized. The water flux and regeneration performance of the hydrogels in the FO process were explored. Results showed that the equilibrium swelling ratio of P(DMAM-co-AMPS) was observed to be 532 g/g, and the swelling behavior followed the Fickian diffusion model. The hydrogels exhibited a significant and reversible deswelling behavior under the stimuli of an external contact electric field. When 2 g/L NaCl solution was used as the feed solution, the hydrogels produced an average water flux of 1.81 L m-2 h-1 during the initial 1 h in the FO desalination process. After 24-h FO operation, a water recovery rate of 67.7% was obtained when the hydrogels were dewatered for 40 min under a voltage of 15 V, showing certain application potentiality.

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