Abstract Precipitation of calcium sulfate dihydrate (i.e., gypsum) on the membrane active layer negatively impacts the efficiency of reverse osmosis (RO) systems by increasing overall operation and maintenance costs. The interfacial free energy between RO membranes and scalants is expected to play a paramount role in crystal nucleation and adsorption. In this work, we modified the surface of a thin-film composite RO membrane with a zwitterionic polymer brush via atom transfer radical polymerization (ATRP) to impart superhydrophilicity for enhanced resistance to gypsum scaling. The zwitterionic polymer coating was optimized and a highly hydrophilic membrane surface displaying a water contact angle of

中文翻译：

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薄膜复合膜上的两性离子涂层延迟反渗透中的石膏结垢

摘要 二水合硫酸钙（即石膏）在膜活性层上的沉淀会增加整体运行和维护成本，从而对反渗透 (RO) 系统的效率产生负面影响。预计 RO 膜和结垢剂之间的界面自由能在晶体成核和吸附中起重要作用。在这项工作中，我们通过原子转移自由基聚合 (ATRP) 用两性离子聚合物刷对薄膜复合 RO 膜的表面进行了改性，以赋予超亲水性以增强对石膏结垢的抵抗力。两性离子聚合物涂层经过优化，高度亲水的膜表面显示水接触角为