聚甲基丙烯酸N,N-二甲氨基乙酯复合纳滤膜的制备

以AIBN为引发剂,采用本体聚合的方法制备了聚甲基丙烯酸N,N-二甲氨基乙酯(PDMAEMA),并采用中空纤维超滤膜技术滤除PDMAEMA水溶液中的低聚物和未反应的单体.以聚砜(PSf)超滤膜为基膜,以所精制的PDMAEMA为水相涂层液,以对二氯苄的正庚烷溶液为有机交联剂,利用界面聚合的方法制备了PDMAEMA/PSf荷正电复合纳滤膜.实验重点研究了PSf基膜和单体浓度、水相pH值及浸涂时间、水相沥干时间、交联反应时间等条件对所制备纳滤膜分离性能的影响,确定了较优的制膜条件.所制备的荷正电纳滤膜对1g/LMgSO4水溶液(0.8MPa,30℃)的截留率为86.7%,水通量为8.4L/(m2.h).

Preparation of Poly [ 2 - ( N, N - dimethyl amino) ethyl methacrylate composite nanofiltration membrane

Poly[2-(N,N-dimethyl amino)ethyl methacrylate](PDMAEMA)was prepared by polymerization using AIBN as initiator. PDMAEMA aqueous solution was puried by hollow fiber ultrafiltration membrane in order to remove oligomers and unpolymerized monomers. PDMAEMA/ polysulfone (PSf) positively charged nanofiltration(NF) membrane was developed by interfacial crosslinking polymerization using PSf ultrafiltration membrane as support membrane, PDMAEMA aqueous solution as coating solution, and p-xylylene dichloride/n-heptane as organic crosslinking agent. The effect of the support membrane, the concentrations of monomers, pH value of the aqueous phase, coating time, drying time, crosslinking time on the seperation characters of the prepared composite NF membrane were carefully studied for preparing the best NF membrane. The results show that the rejection of the positively charged nanofiltration membrane to 1 g/L aqueous MgSO_4 solution is about 86.7%, and the water flux was about 8.4 L/(m~2h).