聚离子液体刷接枝改性PVDF膜及其对药物硫酸氢氯吡咯雷分离性能研究

以聚偏氟乙烯(PVDF)超滤膜为底膜,通过浸渍法使多巴胺(DOPA)在膜表面形成聚多巴胺(PDOPA)层,然后由化学反应固定溴代卤化物,并通过原子转移自由基聚合(ATRP)反应在膜表面接枝聚离子液体刷(PBIVm-Br),以制备聚离子液体刷改性PVDF膜,即PVDF-g-PBIVm-Br膜.结果表明,改性PVDF膜的接触角下降至60°以下且显示出良好的荷正电性.改性膜的药物通量和截留率均大于未改性PVDF膜,分离10 mg·L~(-1)的硫酸氢氯吡咯雷时,改性膜(M4)的药物通量可达27.62 L·m~(-2)·h~(-1),截留率为89.03%,通量恢复率为95.32%.经过60 h分离实验后,膜M4对硫酸氢氯吡咯雷溶液的分离通量维持在18.05 L·m~(-2)·h~(-1),截留率从89.03%上升到92.19%.以上结果表明,聚离子液体刷改性膜在荷正电有机污染物的分离方面具有一定的应用前景.

Poly(ionic liquid) brushes grafted PVDF membrane and its separation properties to the drug clopidogrel hydrogen sulfate

Poly(ionic liquid) brushes grafted polyvinylidene fluoride (PVDF) membranes (PVDF-g-PBIVm-Br) were prepared by the following process:firstly PVDF ultrafiltration membranes were immersed into dopamine(DOPA) solution to form polydopamine (PDOPA) layers on the membrane surface, then the hydroxyl groups on the PDOPA were used for the immobilization of bromo halide by chemical reaction, and then poly(ionic liquid) brushes (PBIVm-Br) were grafted onto the membrane surface by atom transfer radical polymerization (ATRP) reaction. The results indicated that the initial contact angle of the grafted membrane decreased below 60° and also exhibited positively charged properties. The drug flux and rejection of the grafted membranes were greater than those of the original membrane. When separating of 10 mg·L^-1 clopidogrel hydrogen sulfate, the drug flux, rejection and the flux recovery rate of the membrane M4 reached 27.6 L·m^-2·h^-1, 89.03% and 95.32%, respectively. After increasing the separation time for 60 h, the membrane flux was maintained at 18.05 L·m^-2·h^-1 and the rejection increased from 89.03% to 92.19%. The above results indicated that poly(ionic liquid) brushes modified membranes had good application in the separation of the positively charged organic pollutants.