Temperature-sensitive polypropylene membranes prepared by plasma polymerization
Temperature-sensitive polypropylene membranes prepared by plasma polymerization
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DOI：
10.1016/s0376-7388(00)00453-1
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发表时间：
2000-08-30
影响因子：
9.5
通讯作者：
Young, JS
中科院分区：
文献类型：
--
作者：
Liang, L;Shi, MK;Young, JS
采用等离子体聚合技术将聚n -异丙基丙烯酰胺（PNIPAAm）接枝到聚丙烯（PP）微滤膜上。利用傅里叶变换红外光谱（FTIR）对接枝膜表面进行了表征。扫描电镜图表明，PNIPAAm既可以接枝在膜表面，也可以接枝在膜孔中。接枝膜的形态可以通过单体浓度和聚合时间来调节。通过测量动态接触角，观察到表面性能对温度变化的可逆响应。在PNIPAAm的低临界溶解温度（LCST）下，接枝PP膜呈现亲水性表面（接触角提前90度）。我们通过测量接枝膜在不同温度下的水通量来研究接枝膜的开关特性。根据温度和压降，水通量可在25至7500 kg/m(2) h之间变化。膨胀的PNIPAAm链堵塞微滤膜孔，通量降低（关闭状态）。PNIPAAm链在LCST以上收缩并打开微滤膜的孔。因此，水通量增加（在状态上）。讨论了压降对接枝聚丙烯膜水通量的影响。膜孔径的快速而显著的变化可能使接枝PP膜作为药物递送系统的载体成为可能。它们还可以用作多功能分离膜、控制阀和执行器。Elsevier Science B.V.出版
Poly-N-isopropylacylamide (PNIPAAm) was grafted on polypropylene (PP) microfiltration membranes using plasma polymerization. The surface of the grafted membrane was evaluated by Fourier transform infrared (FTIR) spectroscopy. Scanning electron microscopy pictures demonstrated that the PNIPAAm can be grafted either on the surface or in the pores of the membrane. The morphology of the grafted membrane can be adjusted through monomer concentration and polymerization time. Surface properties with a reversible response to temperature change were observed by measuring the dynamic contact angle. Below the low critical soluble temperature (LCST) of PNIPAAm, the grafted PP membrane exhibited a hydrophilic surface (advancing contact angle90 degrees). We investigated the on-off characteristics of the grafted membrane by measuring water flux through the grafted membrane at different temperatures. The water flux can be varied from 25 to 7500 kg/m(2) h, depending on the temperature and pressure drop. The swelling PNIPAAm chains block the pores of the microfiltration membrane, and the flux decreases (off status). The PNIPAAm chains shrink above the LCST and open the pores of the microfiltration membrane. Thus, the water flux increases (on status). The effect of pressure drop on the water flux of the grafted PP membrane was discussed. The rapid and remarkable changes in the pore size of the membrane may make it possible to use the grafted PP membranes as the carrier for a drug-delivery system. They would also be used as multifunctional separation membranes, control valves, and actuators. Published by Elsevier Science B.V.