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Abstract：
Recently, increasing attention of researchers in the field of membrane technology has been paid to the development of membranes based on biopolymers. One of the well-proven polymers for the development of porous membranes is cellulose acetate (CA). This paper is devoted to the study of the influence of different parameters on ultrafiltration CA membrane formation and their transport properties, such as the variation in coagulation bath temperature, membrane shrinkage (post-treatment at 80 °C), introduction to casting CA solution of polymers (polyethylene glycol (PEG), polysulfone (PS), and Pluronic F127 (PL)) and carbon nanoparticles (SWCNTs, MWCNTs, GO, and C60). The structural and physicochemical properties of developed membranes were studied by scanning electron and atomic force microscopies, Fourier-transform infrared spectroscopy, X-ray photoelectron spectroscopy, and contact angle measurements. The transport properties of developed CA-based membranes were evaluated in ultrafiltration of bovine serum albumin (BSA), dextran 110 and PVP K-90. All developed membranes rejected 90% compounds with a molecular weight from ~270,000 g/mol. It was shown that the combination of modifications (addition of PEG, PS, PL, PS-PL, and 0.5 wt% C60) led to an increase in the fluxes and BSA rejection coefficients with slight decrease in the flux recovery ratio. These changes were due to an increased macrovoid number, formation of a more open porous structure and/or thinner top selective, and decreased surface roughness and hydrophobization during C60 modification of blend membranes. Optimal transport properties were found for CA-PEG+C60 (the highest water-394 L/(m2h) and BSA-212 L/(m2h) fluxes) and CA-PS+C60 (maximal rejection coefficient of BSA-59%) membranes.
摘要：
最近,膜技术领域的研究人员越来越重视基于生物聚合物的膜的开发。用于开发多孔膜的一种被充分证实的聚合物是醋酸纤维素(CA)。本文致力于研究不同参数对超滤CA膜形成及其输运特性的影响,如凝固浴温度的变化，膜收缩（80°C后处理），介绍聚合物(聚乙二醇(PEG)，聚砜(PS),和PluronicF127（PL））和碳纳米颗粒（SWCNT，MWCNT,GO,和C60）。通过扫描电子和原子力显微镜研究了开发膜的结构和理化性质，傅里叶变换红外光谱,X射线光电子能谱,和接触角测量。在牛血清白蛋白（BSA）的超滤中评估了开发的基于CA的膜的传输特性，葡聚糖110和PVPK-90。所有开发的膜拒绝90%分子量为〜270,000g/mol的化合物。结果表明，修饰的组合(添加PEG，PS,PL,PS-PL,和0.5wt％的C60）导致通量和BSA截留系数增加，而通量回收率略有降低。这些变化是由于大孔隙数增加，形成更开放的多孔结构和/或更薄的顶部选择性，共混膜的C60改性过程中表面粗糙度和疏水化降低。对于CA-PEGC60（最高的水394L/（m2h）和BSA-212L/（m2h）通量）和CA-PSC60（BSA-59％的最大排斥系数）膜，发现了最佳的传输特性。
