微孔聚丙烯膜表面季铵化及其抗菌性能

Surface Quaternization and Antimicrobial Property of Microporous Polypropylene Membrane

为了赋予微孔聚丙烯膜(MPPM)抗菌能力,发展了一种有效的表面季铵化方法。基于紫外光引发丙烯酸的接枝聚合,通过碳二亚胺活化,将聚亚乙基亚胺(PEI)共价固定于MPPM表面,用环氧丙烷对PEI链上的伯胺和仲胺进行叔胺化,最后再和苄氯反应,成功地使MPPM表面季铵化。采用FTIR、XPS、荧光素二钠盐染色和水接触角对膜进行了表征。采用平板活菌计数法考察了季铵化膜对大肠杆菌和金黄色葡萄球菌的抗菌性能。结果显示,季铵化膜对大肠杆菌和金黄色葡萄球菌均具有强的抗菌活性;增加膜表面阳离子密度或延长接触时间,均能有效提高膜的抗菌能力。

To endow microporous polypropylene membrane （MPPM） with antimicrobial capability, a versatile method was developed to quaternize MPPM surface. Firstly, acrylic acid （AA） was grafted on the MPPM surface via UV irradiation, and subsequent chemical binding of polyethyleneimine （PEI） was effected by activation of carbodiimide. Then, the primary and secondary amine groups on chains of PEI were tertiarily aminated with propylene epoxide. The surface of MPPM was quaternized by the reaction between tertiary amine of PEI and benzyl chloride. Fourier transform infrared spectroscopy （FTIR）, X-ray photoelectron spectroscopy（XPS）, fluorescein disodium salt coloration and static water contact angle were used to characterize the quaternized membranes. The antibacterial capabilities of the quaternized membranes for E. coli and S. aureus were investigated via plate counting method. The results indicate that the quaternized membranes exhibited strong antimicrobial capability for both E. coli and S. aureus, and the antimicrobial capability could be enhanced by increasing the density of positive charge on the surface of quaternized membranes or contact time.