Hou Chengmin, Cao Congjun
Faculty of Printing, Packaging Engineering and Digital Media Technology, Xi'an University of Technology Xi'an 710048 Shaanxi Province People's Republic of China
RSC Adv. 2021 Sep 24;11(50):31675-31687. doi: 10.1039/d1ra06393f. eCollection 2021 Sep 21.
At present, the preparation methods of oil-water separation membranes include chemical vapor deposition, electrospinning, atom transfer radical polymerization, Basically, they all have issues of low recycling rate and incontinuous use. In this paper, the epoxy polymer P(GMA--MMA) obtained by traditional radical polymerization of glycidyl methacrylate (GMA) monomer and methacrylic acid (MMA) monomer, and pentafluoropropionic acid (PFPA) is used to modify polymer P(GMA--MMA) to obtain fluorine-containing epoxy polymer P(GMA--MMA)--PFPA. Secondly, fluorine-containing epoxy polymer P(GMA--MMA)--PFPA and amino-modified nano SiO is blended, and the cotton fabric is dip-coated to obtain a superhydrophobic surface, thereby preparing an oil-water separation membrane. By controlling the solution concentration, dipping time, drying time and other conditions, the superhydrophobic performance of the separation membrane was characterized, and the best construction conditions for the superhydrophobic surface were obtained: 0.3 mg mL polymer concentration, immersion time 6 h, drying temperature 120°, and drying time 4 h, and the maximum water contact angle can reach to 150° ± 2°. Finally, the cotton fabric was modified under the best dipping conditions, and used as an oil-water separation membrane to study the oil-water separation performance of -hexane, -octane, kerosene, chloroform and water mixtures in batch operation and continuous operation. In batch operations, the separation efficiency can reach 99% and can achieve 5 consecutive high-efficiency separations without intermittent drying. In continuous flow operation, oil-water separation can last for more than 12 hours and the separation efficiency can reach 98%. It also has stable oil-water separation performance for oil-water emulsion.
目前,油水分离膜的制备方法包括化学气相沉积、静电纺丝、原子转移自由基聚合等。基本上,它们都存在回收率低和使用不连续的问题。本文通过甲基丙烯酸缩水甘油酯(GMA)单体和甲基丙烯酸(MMA)单体的传统自由基聚合反应得到环氧聚合物P(GMA-MMA),并使用五氟丙酸(PFPA)对聚合物P(GMA-MMA)进行改性,得到含氟环氧聚合物P(GMA-MMA)-PFPA。其次,将含氟环氧聚合物P(GMA-MMA)-PFPA与氨基改性纳米SiO2进行共混,对棉织物进行浸涂以获得超疏水表面,从而制备油水分离膜。通过控制溶液浓度、浸渍时间、干燥时间等条件,对分离膜的超疏水性能进行表征,得到超疏水表面的最佳构建条件:聚合物浓度0.3mg/mL,浸渍时间6h,干燥温度120℃,干燥时间4h,最大水接触角可达150°±2°。最后,在最佳浸渍条件下对棉织物进行改性,并将其用作油水分离膜,研究其在间歇操作和连续操作中对正己烷、正辛烷、煤油、氯仿和水混合物的油水分离性能。在间歇操作中,分离效率可达99%,可实现5次连续高效分离而无需间歇干燥。在连续流操作中,油水分离可持续12小时以上,分离效率可达98%。它对油水乳液也具有稳定的油水分离性能。