单端氨基聚乙二醇的合成及其仿生修饰增强超滤膜抗污染性研究

Study on the Synthesis and Biomimetic Modification of Single Terminal Amino Polyethylene Glycol to Enhance the Anti-fouling Property of Ultrafiltration Membrane

以聚乙二醇和邻苯二甲酰亚胺为原料合成单端氨基聚乙二醇(PEG-NH_(2)),讨论了不同摩尔比(1︰1,1︰2和1︰4)对于合成PEG-NH_(2)纯度的影响,进而利用聚多巴胺二次功能化法,将高纯PEG-NH_(2)仿生修饰于聚偏氟乙烯膜(PVDF)表面,构建抗污染PVDF膜。利用核磁氢谱分析验证了PEG-NH_(2)的成功合成,通过X射线光电子能谱仪、扫描电子显微镜、原子力显微镜研究了PEG-NH_(2)对PVDF膜表面结构的影响,同时利用接触角、渗透分离性能等分析了PEG-NH_(2)对PVDF膜表面抗污染性能的影响。结果表明,PEG-NH_(2)仿生修饰在PVDF膜表面形成了稳定的抗污染改性层,膜表面变得更为平滑,增强了膜表面亲水性和抑制蛋白黏附性能,并显著提升了改性膜的渗透分离和动态抗蛋白污染性能,在化工废水处理领域具有潜在的应用前景。

Single-ended amino polyethylene glycol was synthesized from polyethylene glycol and phthalimide.The influence of different molar ratios(1︰1,1︰2 and 1︰4)on the purity of PEG-NH_(2) was discussed.Then,high purity PEG-NH_(2) was biomimetic modified on the surface of polyvinylidene fluoride membrane(PVDF)by means of polydopamine secondary functionalization method to build anti-fouling PVDF membrane.The single-end amino polyethylene glycol was successfully verified by hydrogen nuclear magnetic spectrum analysis.The effect of PEG-NH_(2) on PVDF membrane surface structure was studied by X-ray photoelectron spectroscopy(XPS),scanning electron microscope(SEM)and atomic force microscope(AFM).Meanwhile,the effect of PEG-NH_(2) on anti-fouling performance of PVDF membrane was analyzed by contact angle and permeability separation.The results showed that PEG-NH_(2) biomimetic modification formed a stable anti-fouling modified layer on the PVDF.Thus the membrane surface became smoother and showed enhancing hydrophilicity and anti-protein adhesion performance.Also,the permeability separation and dynamic anti-protein contamination performance of the modified membrane were significantly improved.And it has a potential application prospect in the field of chemical wastewater treatment.