辣素衍生物改性PVDF膜的制备及其抗菌性能

以甲基丙烯酸甲酯（MMA）和天然辣素8-甲基-N-香草基-6-壬烯酰胺（Capsa）为单体，通过自由基聚合合成辣素衍生物PMMA-Capsa。将PMMA-Capsa与聚偏氟乙烯（PVDF）共混，通过非溶剂诱导相转化法制备PVDF/PMMA-Capsa分离膜，系统地研究了PMMA-Capsa含量对所制备的分离膜表面化学组成、形态结构、亲水性能、抗菌性能及渗透性能的影响。结果表明在成膜过程中PMMA-Capsa倾向于分布在分离膜的表面和孔道表面。随着铸膜液中PMMA-Capsa含量的增加，所制备的分离膜断面结构中海绵层结构逐渐消失，分离膜容易形成粗糙的微孔状表面。PMMA-Capsa的引入使分离膜表面水接触角从88.4°降低到73.1°。渗透实验结果表明分离膜的纯水通量随着PMMA-Capsa含量的增加而增加，而对牛血清蛋白（BSA）的截留率逐渐降低，所制备的PVDF/PMMA-Capsa分离膜的通量恢复率高于纯PVDF膜。PVDF/PMMA-Capsa分离膜具有优异的抗菌性能，对金黄色葡萄球菌的抗菌效率最高可达97.2%。

Preparation and anti-bacterial ability of PVDF membrane modifiedwith capsaicin derivative

Capsaicin derivative(PMMA-Capsa) was synthesized via radical copolymerization using methyl methacrylate(MMA) and 8-methyl-N-vanillyl-6-nonenamide (Capsa) as monomers. PMMA-Capsa was blended with PVDF to prepare the PVDF/PMMA-Capsa membrane using non-solvent induced phase inversion method. Effects of PMMA-Capsa concentration on the surface chemical composition, morphology, hydrophilicity, anti-bacterial activities and permeation properties of resultant membranes were investigated systematically. The result showed that the PMMA-Capsa was inclined to distribute onto the membrane surface and pore channel surface during the membrane formation process. With the increase of PMMA-Capsa concentration in the casting solution, the sponge-like structure at the cross-sections of membranes disappeared gradually, and the microporous and rough membrane surfaces were easily formed. The introduction of PMMA-Capsa resulted in the decrease in water contact angle of membrane surface from 88.4° to 73.1°. Filtration experiments indicated that the pure water flux of the membranes increased, whereas the rejection ratio of bovine serum albumin(BSA) decreased with the increment of PMMA-Capsa concentration. The flux recovery ratios of the prepared PVDF/PMMA-Capsa membranes were higher than that of the pristine PVDF membrane. The PVDF/PMMA-Capsa membrane exhibited excellent biofouling resistance and the bactericidal efficiency against S. aureu was as high as 97.2%.