Marino Tiziana, Russo Francesca, Figoli Alberto
Institute on Membrane Technology (ITM-CNR), Via Pietro Bucci, Cubo 17C, 870 36 Rende (CS), Italy.
Membranes (Basel). 2018 Sep 1;8(3):71. doi: 10.3390/membranes8030071.
The present investigation reports as it is possible to prepared polyvinylidene fluoride (PVDF) membranes for microfiltration (MF) and ultrafiltration (UF) applications, by using triethyl phosphate (TEP) as non⁻toxic solvent in accordance with the Green Chemistry. Casting solutions containing different concentrations of polyethylene glycol (PEG) were prepared in order to study its effect on the final membrane morphology and properties. The possibility to finely modulate membrane properties was also investigated by applying two different membrane preparation techniques, the Non-Solvent Induced Phase Separation (NIPS) and its coupling with Vapour Induced Phase Separation (VIPS). Membranes' morphology was detected by Scanning Electron Microscopy (SEM). Thickness, porosity, contact angle, pore size and water permeability were also recorded. Both the PEG content in the dope solution and the selected time intervals during which the nascent films were exposed to established relative humidity and temperature were found to play a crucial role in membrane formation. In particular, it was demonstrated as, by varying PEG content between 10 and 20 wt %, and by setting the exposure time to humidity at 0/2.5/5/7.5 min, membranes with different pore diameter and bicontinuous structure, suitable for UF and MF applications, could be easily obtained.
本研究报告了根据绿色化学原理，使用磷酸三乙酯（TEP）作为无毒溶剂制备用于微滤（MF）和超滤（UF）应用的聚偏氟乙烯（PVDF）膜的可能性。制备了含有不同浓度聚乙二醇（PEG）的铸膜液，以研究其对最终膜形态和性能的影响。还通过应用两种不同的膜制备技术，即非溶剂诱导相分离（NIPS）及其与气相诱导相分离（VIPS）的耦合，研究了精细调节膜性能的可能性。通过扫描电子显微镜（SEM）检测膜的形态。还记录了膜的厚度、孔隙率、接触角、孔径和水渗透性。发现铸膜液中的PEG含量以及新生膜暴露于既定相对湿度和温度的选定时间间隔在膜形成中都起着关键作用。特别是，通过将PEG含量在10至20 wt％之间变化，并将暴露于湿度的时间设置为0/2.5/5/7.5分钟，可轻松获得具有不同孔径和双连续结构、适用于UF和MF应用的膜。
