共溶剂对反渗透复合膜表面形貌及分离性能的影响

Effect of Co-Solvents on the Surface Morphology and Permeability of Reverse Osmosis Composite Membranes

以聚砜超滤膜为底膜,间苯二胺为水相单体,均苯三甲酰氯为有机相单体,通过界面聚合的方法制备了聚酰胺反渗透复合膜。研究了有机相共溶剂1,3-二甲基-2-咪唑啉酮、N,N-二甲基丙烯基脲、磷酸三丁酯对聚酰胺反渗透复合膜表面形貌及分离性能的影响。扫描电子显微镜观察表明,共溶剂的存在有助于复合膜表面形成"叶片状"结构;傅里叶变换红外光谱仪则对聚酰胺分离层化学结构进行了分析。通过改变共溶剂的种类和含量,可有效改变聚酰胺复合膜的表面形貌,最终调控膜的水通量和截留率。

M-phenylenediamine as the water phase monomer, trimesoyl chloride as the organic phase monomer, polyamide reverse osmosis membranes were prepared by interfacial polymerization on the polysulphone ultrafiltration membrane. The effect of different co-solvents（DMI, DMPU, TBP） on the surface morphology and permeability of polyamide reverse osmosis membrane was studied. The result of SEM illustrated as-prepared membranes had the leaf-shaped polyamide structure. The chemical structure of membranes discriminate layer was analyzed by ATR-FTIR. The surface morphology of polyamide reverse osmosis membranes was changed by the types and content of co-solvents added, thereby permeability and rejection were controlled.