纳米银在水处理膜中的应用进展

水处理膜是具有选择性分离功能的材料,利用水处理膜的选择性分离可实现污水的不同组分的分离、纯化、浓缩。基于纳米银的独特性质,将其引入水处理膜可使纳米银复合膜具有较强的抗生物污染能力。本文综述了近年来将纳米银引入应用较广泛的微滤膜、超滤膜和纳滤膜以及反渗透膜这些水处理膜中以改善膜的抗污染性能的研究进展。此外,指出了提高纳米银水处理复合膜抗菌的持续性以及开发环境友好型的复合膜是未来的发展方向。     

有机-无机杂化复合膜的研究进展

有机-无机杂化复合膜结合了有机复合膜和无机材料的优良性能,已成为分离膜领域的一个研究热点。本文以有机无机杂化复合膜的结构对其进行分类,综述了组分间以化学键相结合的有机-无机杂化复合膜的研究现状,归纳了有机-无机杂化复合膜的制备技术、优越性以及最新的研究进展,并针对杂化复合膜研究中现存的不足和今后研究的发展,提出了一些建议。     

功能化碳纳米管/聚合物复合分离膜

碳纳米管不仅具有优异的力学性质和超大的比表面积,同时具有优良的传输特性,将其添加到聚合物中制备复合分离膜,具有广阔的应用前景。通过化学改性将碳纳米管功能化,提高其在聚合物中的分散性,制备碳纳米管/聚合物复合膜。本文在介绍了碳纳米管功能化、碳纳米管/聚合物复合膜制备方法的基础上,综述了功能化碳纳米管的加入对复合分离膜亲水性、水通量、机械稳定性以及分离等性能的影响。总结了近年来对碳纳米管在聚合物膜内定向排列的研究进展及碳纳米管定向对复合膜相关性能的影响。由于碳纳米管材料的各向异性,利用电场、磁场及流场等对碳纳米管在聚合物膜内的分布进行定向,从而充分利用其优异的性能,是该类复合膜的研究方向。     

凹凸棒石复合分离膜的研究进展

凹凸棒石（ATP）是一种廉价易得的天然粘土矿物，具有比表面积大、阳离子交换容量高、表面官能团丰富等特点，通过不同的方法改性，可以与各种基膜结合形成复合膜。综述了ATP复合分离膜的不同制备方法，比较了其优缺点；总结了ATP添加量对复合膜拉伸强度、杨氏模量、断裂伸长率等力学性能的影响，进而介绍了ATP复合分离膜在CO2分离、重金属分离、染料分离、油水分离等方面的应用，并分析了其分离机理。最后展望了ATP复合分离膜的面临挑战和研究方向。     

复合陶瓷膜的研究现状及发展前景

在简要介绍复合陶瓷膜这一概念的基础上,对非对称性无机复合相顶层分离膜的研究现状进行了综述,概述了近期国内对以Al2O3,SiO2,ZrO2,TiO2为基础的不同材质的复合陶瓷膜的研究进展,提出了研究中存在的问题及复合膜的发展前景。     

金属有机骨架/聚酰胺薄层纳米复合膜的研究进展

相较于传统聚酰胺薄层复合（TFC）膜,金属有机骨架/聚酰胺薄层纳米复合（TFN）膜得益于MOFs材料的高比表面积、有序可控的孔隙结构、良好的聚合物相容性和可定制的化学功能,展现出更高的渗透选择性,在工业应用中显示出巨大的分子和离子分离潜力。本文首先简述了MOFs聚酰胺复合膜的研究背景,然后从MOFs材料的特性和MOFs聚酰胺复合膜的制备策略两个方面出发,总结了MOFs聚酰胺膜研究的最新进展。讨论了MOFs的物化特征在TFN膜的微观结构和分离性能中起的作用;介绍了MOFs聚酰胺复合膜的制备策略,重点对MOFs负载方法及效率进行了分析。最后简述了MOFs聚酰胺复合膜在气、液体系分离中的应用;对MOFs聚酰胺膜在应用过程中的稳定性问题进行了分析,并对未来MOFs聚酰胺复合膜优化MOFs负载和功能性设计的研究进行了展望。     

聚乙烯醇复合膜及其在水处理中的应用研究进展

PVA具有良好的亲水性、耐污染性、热稳定性和化学稳定性等,已成为被广泛应用的亲水性膜材料之一,尤其是作为复合分离膜的活性分离层材料。对PVA复合膜的制备方法和各种PVA复合膜(超滤膜、纳滤膜、反渗透膜和渗透汽化膜)在水处理中的应用作了详细综述,以期为高性能PVA复合膜的制备及其在水处理中应用提供一定的理论指导。     

分离用金属陶瓷复合膜及研究进展

金属陶瓷复合膜是由金属膜及表面陶瓷活性膜层复合而成,综述金属膜制备方法及金属膜表面溶胶凝胶法制备陶瓷活性层膜制备技术,为金属陶瓷复合膜制备提供理论意义。论述国内外金属陶瓷复合膜研究进展,对金属陶瓷复合膜制备工艺技术及应用范围展望。     

炭-炭复合膜制备的探索研究

以煤沥青基炭分离膜为支撑体，采用聚合物溶液涂层或浸渍制备出了炭－炭复合分离膜，测试了高纯H2，CO2，N2和O2单组分在炭－炭基复合分离膜上的渗透速率，计算了各气体组分的理想分离系数。结果显示以聚乙二醇水溶液进行表面涂层制备的炭－炭复合膜，其气体分离性能与炭分离膜相比稍有提高，以酚醛树脂N，N－二甲基乙酰胺溶液和加有分散剂的酚醛树脂乙醇溶液涂层制备的炭－炭复合膜在分离性能上都有较大提高，尤其加有分散剂的酚醛树脂乙醇溶液涂层后可使H2／CO2的分离系数达16．0左右，而采用酚醛树脂乙醇溶液涂层和浸渍得到的炭－炭基复合膜的气体渗透速率和分离系数均下降。     

复合中空纤维超滤膜的研制

本文就复合中空纤维超滤膜的制备工艺和成膜条件对膜性能影响进行了系统的研究，实验表明，对外压式中空纤维膜，内凝固液条件的改变，主要影响复合膜的内致密层，进而影响膜的透过通量，但对膜的截留孔径无影响，随空中行走距离增大，膜的透过通量减小，截留孔径增大。另外，通过基膜的选定与内凝固液的调节，复合中空纤维膜的分离孔径主要取决于复合层膜，即在适宜的条件下，基膜不影响复合膜的分离孔径，同时也不决定复合中空纤维     

Poly(vinyl alcohol)‐based polymeric membrane: Preparation and tensile properties

A series of poly(vinyl alcohol) (PVA)‐based single‐layer organic polymeric membranes were prepared via the crosslinking of PVA with different amounts of formaldehyde. Meanwhile, for comparison, both a three‐layer organic polymeric membrane and a hybrid composite membrane were also prepared by the layer‐upon‐layer method. Their thermal stability and tensile properties were investigated to examine the effect of crosslinking on the membrane performances. Thermogravimetric analysis and differential scanning calorimetry thermal analyses showed that the thermal degradation temperature of the single‐layer crosslinked membrane C reached up to 325°C. Tensile testing indicated that the three‐layer organic polymeric membrane E had excellent tensile strength among these single‐layer and three‐layer membranes. The swelling properties revealed that the swelling degree value of these membranes decreased with an increase in methanol concentration; this suggests that they were not easily swollen by the methanol solution, which is meaningful for the separation of organic mixtures. Field emission scanning electron microscopy images exhibited that the crosslinking of functional groups impacted their structures and confirmed that their mechanical properties were related to their structures. These findings suggest that the crosslinking of functional groups is an effective method for adjusting the tensile strength of PVA‐based organic polymeric membranes and related hybrid composite membranes. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

耐溶剂复合纳滤膜的研究进展

耐溶剂纳滤是一种新型的膜分离技术,用于有机混合物的分离。商品耐溶剂纳滤膜大多是采用相转化法制备的整体皮层非对称膜,膜皮层较厚,通量较低。耐溶剂复合纳滤膜由基膜和分离层组成,具有薄皮层、高溶剂通量和高溶质截留率的优点。耐溶剂复合纳滤膜的制备与改性也因此成为近年来的研究热点。本文从界面聚合、表面涂覆、层层自组装、原位生长、有机-无机杂化和表面改性六个方面介绍耐溶剂复合纳滤膜的研究进展,最后对其发展前景进行展望。     

Pervaporation membranes based on imide‐containing poly(amic acid) and poly(phenylene oxide)

Three imide‐containing poly(amic acids) were synthesized and used for homogeneous and composite membrane preparation. The transport properties of composite membranes consisting of an imide‐containing poly(amic acid) top layer on an asymmetric porous poly(phenylene oxide) support were studied in the pervaporation of aqueous solutions of organic liquids (ethanol, isopropanol, acetone, and ethylacetate) and organic/organic mixtures (ethylacetate/ethanol, methanol/cyclohexane). For most of the aqueous/organic mixtures, the composite membranes exhibited dehydration properties. Dilute aqueous solutions of ethylacetate were an exception. In these solutions, the composite membranes exhibited organophilic properties, high permeability, and selectivity with respect to ethylacetate. In the pervaporation of methanol/cyclohexane mixtures, methanol was removed with very high selectivity. To account for specific features of pervaporation on the composite membranes, the sorption and transport properties of homogeneous membranes prepared from polymers comprising the composite membrane [imide‐containing poly(amic acids) and poly(phenylene oxide)] were studied. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2361–2368, 2003     

Nanofiltration membranes prepared by interfacial polymerization on thin-film nanofibrous composite scaffold

Nanofiltration (NF) membranes, consisting of a composite barrier layer prepared by interfacial polymerization of polyamide around the ultra-fine cellulose nanofibers (CN) layer in a thin-film nanofibrous composite (TFNC) scaffold, were demonstrated. Two interfacial polymerization pathways (termed IP and IP-R), regarding the arrangement of the aqueous and organic phases, were investigated. It was found that interfacial polymerization with the aqueous phase above the organic phase (IP-R) yielded better filtration performance, i.e., IP-R based membranes exhibited a higher MgCl₂ rejection than IP based membranes. Transmission electron microscopy (TEM) observation indicated that the denser part of the barrier layer was on the CN layer surface of IP-R based membranes, whereas this portion was deeply immersed in the CN layer of IP based membranes. To investigate the structure and property relationship of the composite barrier layer, both IP and IP-R based membranes were treated with 1% trimesoyl chloride (TMC) in hexane. After treatment, the rejection of NaCl was found to increase from 74% to 91% for IP-R based membranes, while remained unchanged (∼75%) for IP based membranes. This behavior can be explained by the decrease in pore size due to the cross-linking of TMC and secondary amino groups in the barrier layer of IP-R based membranes, while the permeability in IP based membranes was probably mainly controlled by the water passage through channels formed at the interface between CN and polymer matrix in the barrier layer of IP based membranes, which is not dependent of the cross-linking reaction.     

Proton conducting membranes based on sulfonated poly(ether ether ketone)/TiO2 nanocomposites for a direct methanol fuel cell

This paper presents an evaluation of the effects of titanium dioxide nanoparticles in sulfonated poly(ether ether ketone) (SPEEK) with a sulfonation degree of 57%. A series of inorganic/organic hybrid membranes was prepared with a systematic variation of titanium dioxide nanoparticle content. Their water uptake, methanol permeability and proton conductivity as a function of temperature were investigated. The results obtained show that the inorganic oxide network decreases the proton conductivity and water swelling. It is also found that increasing the inorganic oxide content leads to a decrease of methanol permeability. In terms of morphology, the membranes are homogeneous and exhibit good adhesion between inorganic domains and the polymer matrix. The proton conductivity and fuel cell performances of the nanocomposite membranes showed very good prospective in direct methanol fuel cell usages. The properties of the composite membranes are compared with those of standard Nafion membranes. Copyright © 2006 Society of Chemical Industry     

Polymeric homogeneous composite membranes for separations in organic solvents

A new generation of organic solvent nanofiltration (NF) composite membranes was prepared combining a support layer with a selective layer made both from the same polymeric material (P84 copolyimide). These membranes, homogeneous in composition, but composite in structure, were defined as polymeric homogeneous composite (PHC) membranes. The composite membranes have the advantage over the asymmetric ones that each layer can be optimized independently. Moreover, the use of the same material for the preparation of both, the selective and the support layer, ensures a high affinity between the two layers and increases the long‐term stability of the composite membranes, reducing the possibility of delamination phenomena. In the design of the PHC membranes, a great attention was devoted to the support layer development. The effects of the composition of the casting solutions on the structure of porous P84 copolyimide membranes were investigated allowing to identify the conditions for the preparation of highly permeable, chemically, and mechanically stable P84 sponge like porous membranes. PHC membranes were prepared by coating and controlled solvent evaporation of a P84 solution on the optimized support crosslinked by reaction with a diamine (1,5‐diamino‐2‐methylpentane). Pure solvent permeation test and rejection experiments were carried out on the P84 supports and the corresponding PHC membranes in aggressive organic solvents like N‐methyl‐2‐pyrrolidone and N,N‐dimethyformamide, in which the original polymer was soluble. The PHC membrane resulted completely stable over long times (>96 h). © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Sol-Gel纳米无机/有机复合材料的研究进展及其应用

介绍了无机/有机复合纳米杂化材料的主要制备方法Sol-Gel法和用途,综述了Sol-Gel无机/有机复合纳米杂化材料的研究现状以及其最新进展,展望了无机/有机复合纳米杂化材料的发展趋势。     

有机-无机杂化材料制备质子交换膜的研究进展

综述了近年来采用有机-无机杂化材料制备质子交换膜的研究进展，重点介绍了由掺入了质子导电单元或经过磺化的有机-无机杂化材料制得的质子交换膜及由带磺酸基的有机硅通过溶胶-凝胶工艺制备的有机-无机杂化质子材料制得的交换膜，并从制备方法出发分析了每种质子交换膜的性能。     

Asymmetric Inorganic Membranes Through Langmuir–Blodgett Deposition and Plasma Processing

Nanoporous 7930 Vycor silica tubes with Langmuir–Blodgett (LB) deposited arachidic acid salts undergo oxidative plasma treatment to yield fully inorganic asymmetric membranes. Membranes from precursors with different numbers of LB layers are examined by differential, integral and relative permeability methods for the determination of the structural characteristics of the separating top layer. The membrane top layer is found to be dominated by medium size micropores, while a small population of defective surface sites (partially covered original pores) is also present. The gas separation potential of inorganic asymmetric membranes from ceramic oxide-LB film composites is discussed.     

Solvent‐resistant nanofiltration membranes based on multilayered polyelectrolytes deposited on silicon composite

Alternating deposition of oppositely charged polyelectrolyte complexes (PECs) on inorganic–organic composite membranes can efficiently overcome the drawback of microcracks induced by inorganic particles. Different bilayers of Poly (diallyldimethylammonium, chloride)/sulfonated poly(ether ether ketone) (PDDA/SPEEK) were first deposited on the charged silicon composite with hydrolyzed polyacrylonitrile (PAN‐H) support and evaluated for solvent resistant nanofiltration membranes (SRNF) application. The morphology of the membranes was studied in detail via SEM and AFM. Because of Donnan exclusion, the multilayered PEC silicon composite membranes showed very high retentions up to 99% for negatively charged solutes (Rose Bengal (RB), 1017 Da) in the pressure driven filtration of isopropanol (IPA) solutions. For the first time, PEC‐based silicon composite membranes were also applied in the filtration of organic solvents, where they were found to combine a remarkable stability in polar solvents with high fluxes and retentions. Compared with silicon composite membranes, the introduction of multilayered PDDA/SPEEK can efficiently improve the membrane performance and overcome the drawback induced by inorganic fillers. PEC‐based silicon composite membranes thus show excellent prospective use in SRNF. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013