TiO_2/ZnO纳米多孔复合膜制备及光催化性能研究

分别采用水热处理和添加有机物的方法制备了TiO2/ZnO纳米多孔复合膜,利用XRD、SEM、TEM和EDS对薄膜进行了分析表征,通过甲基橙降解研究了多孔膜的光催化性能。结果表明:采用这两种方法都可获得具有孔洞特征的多孔复合膜,对添加有机物法制备的多孔膜进行的光催化降解实验表明该多孔膜光催化性能明显优于致密复合膜。     

直接研磨法制备漆酚铅聚合物及其自组装

以直接研磨法制备漆酚铅聚合物(ULP),采用UV、FT-IR EDS及TG等手段对其进行表征,同时以Breath Figures法制备ULP多孔膜和微球。实验结果表明:采用直接研磨法可成功制备ULP,ULP具有良好的耐热性。以Breath Figures法可制备形貌规整,尺寸较为均匀的ULP多孔膜和微球。     

胺基化多孔再生纤维素膜的制备及其吸附性能的研究

在制备多孔再生纤维素膜的基础上,采用固-固相界面反应的TEMPO氧化法制备了氧化纤维素膜,通过乙二胺接枝改性成功制备了一种胺基化多孔再生纤维素膜。采用红外光谱、X-射线衍射、扫描电镜等对其结构进行表征,并研究了其对阴离子染料二甲酚橙的吸附性能。实验结果表明:改性纤维素膜上成功引入了胺基,且保留了多孔的纤维素膜结构;该改性膜对二甲酚橙具有良好的吸附效果,能够较快达到吸附平衡,其染料去除率高达92%。该吸附过程符合准二级动力学方程和Freundlich等温方程。     

多孔壳聚糖膜的制备表征及其吸附性能研究

以琼胶固体颗粒为致孔剂,通过热致相转移法制备了的多孔壳聚糖膜,并通过FT-IR和SEM对其进行了表征,也考察了其对有机染料二甲苯蓝FF的吸附性能。结果表明,以琼胶作为制孔剂可以制备出性能良好的多孔壳聚糖膜,在吸附有机染料方面,多孔壳聚糖膜PCS-2对二甲苯蓝FF的吸附量是壳聚糖膜的1.3倍。另外,作为对比,本文也制备和表征了琼胶-壳聚糖共混薄膜。     

全氟滤芯微孔膜虚拟仿真实验的应用

通过虚拟仿真实验来改善教师的教学模式和学生的学习模式已成为国内高校进行教学改革与创新的手段之一。全氟滤芯微孔膜虚拟仿真实验以聚四氟乙烯膜的制备、表征和在乙腈提纯中的应用为主线,涵盖了包括聚四氟乙烯膜的制备,聚四氟乙烯滤膜表面性质的表征等5个虚拟仿真实验模块。在高分子材料加工与成型课程中开展该虚拟仿真实验项目,能丰富教学内容、拓宽师生的视野、提升学生创新意识和专业应用能力和强化教学效果。     

小口径聚氨酯多孔管的制备与表征

首先合成聚醚型聚氨酯和聚硅氧烷改性聚氨酯并设计制作小口径聚氨酯多孔管的模具,调节聚氨酯溶液浓度,以及聚醚型聚氨酯和聚硅氧烷改性聚氨酯的比例,采用冷冻干燥的方法制备出了一系列不同孔径和结构的小口径聚氨酯多孔管和多孔膜。通过扫描电镜表征不同浓度含量多孔管的孔径大小、数量及分布。通过X-光电子能谱和接触角表征了聚氨酯多孔膜的表面元素分布和亲疏水性能。结果表明,8%的聚醚型聚氨酯,及其与20%和30%聚硅氧烷改性聚氨酯共混形成的小口径多孔管孔径和孔的分布上较均匀,为小口径聚氨酯人工血管的制作奠定了实验和理论基础。     

高度有序多孔氧化铝模板影响因素的研究

在酸性电解液中,用阳极氧化法制备得到了多孔阳极氧化铝(anodic aluminum oxide,AAO)模板。用金相显微镜观察了铝箔退火后表面上的晶界,并结合扫描电镜对多孔氧化铝薄膜进行了观察和表征。研究了影响多孔氧化铝模板孔洞有序性的关键性因素。实验结果表明,多孔阳极氧化铝膜的有序度依赖于铝箔预处理、氧化电压和电解液等的选择。     

磁性温度感应微囊膜的制备与表征

合成了亲油Fe3O4纳米颗粒,然后采用界面聚合法制备了磁性聚酰胺多孔微囊膜,最后用等离子体填孔接枝聚合法将聚N-异丙基丙烯酰胺(PNIPAM)接枝到微囊的多孔膜上,制得了磁性温度感应微囊膜.利用X射线衍射(XRD),傅里叶变换红外光谱(FT-IR),透射电镜(TEM)对Fe3O4颗粒进行了表征;用扫描电镜(SEM)、振动样品磁强计(VSM)、磁场分离实验和对VB12的温度感应控释实验对微囊进行了表征.结果表明,未接枝的微囊膜为非对称多孔结构,接枝微囊膜具有超顺磁性,在水溶液中的磁场响应性能良好,对模拟药物有一定的温度感应控制释放特性.     

规整填料型加氢脱硫催化剂的制备及性能评价

用电化学方法制备多孔氧化铝膜,并负载Mo-Co活性组分制得了金属支撑-多孔层规整填料型加氢催化剂。采用BET和SEM技术表征了多孔性氧化铝膜的物理结构,并考察了电解及后处理条件的影响。结果表明,电解液浓度、氧化时间、水封时间、水封温度等对多孔氧化铝膜的比表面积影响显著。采用二次氧化的方法,在质量分数为4%的草酸电解液、氧化时间1 h、80℃水封3 h条件下,所制备的多孔氧化铝膜具有相对较大的比表面积。汽油重馏分加氢反应结果表明该类催化剂具有较高的催化活性和选择性。     

高度有序的多孔型铝阳极氧化膜的制备

以硫酸为电解液研究了多孔阳极氧化铝膜的制备,并采用场发射扫描电子显微镜对多孔氧化铝膜的形貌进行表征.结果表明:氧化电压在24～26 V时能够得到孔径为25～30 nm的多孔氧化铝膜.在不同电压下进行阳极氧化时,多孔氧化铝形成过程均经历了阻挡层形成、多孔层萌生及多孔层稳定生长三个阶段,但多孔层萌生及稳定生长的电流密度随氧化电压的升高而增加.当氧化时间为6h时氧化膜厚度达到最大值38nm.对多孔氧化铝膜进行XPS分析表明,氧化铝膜的主要成分为非晶态Al2O3.     

Analysis of compaction and life‐time prediction of porous polymer membranes: influence of morphology,diffusion and creep behaviour

In membrane applications, large values of permeability and selectivity are generally desired during the whole period of application. The permeability of porous polymer membranes often is reduced by the effect of compaction. Compaction of polymer membranes is a time‐dependent process which is strongly determined by the viscoelastic properties of the polymer and its plasticisation caused by the feed medium (e.g. a liquid medium or a process gas in the case of porous support structures). In this study, the time‐dependent compaction of porous polymer membranes under pressure is modelled. The influence of viscoelastic and diffusion properties of the polymer material on the permeability of the membrane is analysed for different types of membrane morphologies. The life‐time of a porous polymer membrane is associated with the time at which the glass transition is achieved in a creep experiment. Equations are derived in order to estimate the maximum life‐time of polymer membranes based on compaction. The analysis reveals that the diffusion coefficient, the average retardation time in creep, the magnitude of creep compliance and the time–temperature–pressure shift factor strongly influence compaction of microporous membranes. Generally, a larger tortuosity at constant porosity yields a lower life‐time of the membrane. Buckling of cell struts is the dominant failure mechanism in porous membranes with a very high porosity and allows an estimation of life‐time. © 2016 Society of Chemical Industry     

Formation,morphology and control of high-performance biomedical polyurethane porous membranes by water micro-droplet induced phase inversion

Biomedical polyurethane (BPU) porous membranes with controlled morphology and excellent permeability and mechanical properties were prepared via a method involving a phase inversion induced by water micro-droplets, which were generated by an ultrasonic atomizer. The cross-section morphology, air permeability and mechanical properties of the porous membranes were investigated. The SEM images demonstrated that the adjacent pores were connected by a micro-hole, serving as a “backdoor” for the pore. An interconnected porous structure was obtained, improving the air permeability of the BPU membrane relative to the membrane produced by immersion precipitation. Our studies indicated that the diameter of the pores in the membrane depended on the solution viscosity, allowing porous membranes with a desired morphology to be obtained by adjusting the polymer concentration and solution viscosity. The application of micro-droplets of water during membrane preparation reduced the exchange rate between the solvent and nonsolvent, resulting in the microphase separation of polymer molecules and the formation of a uniform porous structure in the membrane, which improved the air permeability and mechanical properties of the BPU porous membranes. This is a simple and effective preparation method for high-performance porous membranes with potential applications in tissue engineering scaffolds, controlled-release drug delivery and vascular grafts.     

Flexible bi-continuous mesostructured inorganic/polymer composite membranes

Flexible bi-continuous mesostructured polymer/inorganic composite membranes have been synthesized by undertaking co-assemblies of surfactants and inorganic sol-gel processes inside pores of a preformed porous polymer membrane such as PP porous membrane Celgard^® 2400. The pores are interconnected across the membranes, therefore the continuity of the inorganic mesopores across the membranes is guaranteed in principle. The solvent ethanol used for silica sol is conducive to the synthesis of inorganic materials such as silica within the pores although the PP membrane is hydrophobic. The composite membranes show new properties such as transparency, flexibility, uniform nanosized pores and enhanced permeability.     

Microporous polyurethane/acrylate gel polymer electrolyte obtained by emulsion polymerization

A novel polyurethane/acrylate (PUA) porous gel electrolyte was prepared by a new method, emulsion polymerization. Compared with the traditional phase inversion method, the new method can eliminate the pollution from solvent and decrease the cost of production. The swelling properties and morphology of the porous polymer membranes were characterized. The porous membranes, made by emulsion polymerization, could absorb large quantities of electrolyte solution to form porous gel electrolytes. The gel electrolytes have good solvent retention ability and high ionic conductivity. Copyright © 2004 Society of Chemical Industry     

功能化聚四氟乙烯微孔膜的研究进展

功能化PTFE微孔膜兼具PTFE微孔膜的优异特性及功能高分子的特殊性能,选择性透过、催化、传输药物、抗菌、质子交换等特殊功能的聚四氟乙烯（PTFE）微孔膜极具应用潜力。本文综述了PTFE微孔膜的特性,总结了近年来采用辐射接枝、表面沉积、涂覆或共混等方法功能化PTFE微孔膜的最新研究进展及其在化工、医学、服装、电子等领域功能化应用的最新成果,并指出目前存在的问题,对今后的研究提出了展望。     

Preparation of silica nanospheres and porous polymer membranes with controlled morphologies via nanophase separation

ABSTRACT: We successfully synthesized two different structures, silica nanospheres and porous polymer membranes, via nanophase separation between silica sol and polymer. Silica sol, which was in-situ polymerized from tetraorthosilicate, was used as a precursor. Subsequently, it was mixed with a polymer that was used as a matrix component. It was observed that nanophase separation occurred after the mixing of polymer with silica sol and subsequent evaporation of solvents, resulting in organizing various structures, from random network silica structures to silica spheres. In particular, silica nanospheres were produced by manipulating the mixing ratio of polymer to silica sol. The size of silica beads was gradually changed from micro- to nanoscale, depending on the polymer content. At the same time, porous polymer membranes were generated by removing the silica component with hydrofluoric acid. Furthermore, porous carbon membranes were produced by using carbon source polymer through the carbonization process.     

Porous nylon‐6 membranes with dimethylamino groups for low pressure desalination

Porous Nylon‐6 membranes with dimethylamino groups were prepared by coagulating the polymer‐formic acid solution into water. The effect of LiCl addition in the polymer cast solution on filtration characteristics of the resultant membranes was examined. It was found that resultant membranes have porous structure and show molecular size exclusion property under 0.025–0.1 MPa of applied pressure. Desalination property of the porous membranes was investigated using NaCl solution containing 0.05–0.85 mM concentration. The porous membranes showed effective rejection to saline at lower than 0.2 mM NaCl concentration. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 75: 1546–1553, 2000     

Properties of cation-exchange membranes prepared by radiation grafting of acrylic acid onto tetrafluoroethylene–ethylene copolymers

Some properties of the ion-exchange membranes prepared by simultaneous and preirradiation techniques of grafting of acrylic acid onto tetrafluoroethylene–ethylene copolymer films, including porous microfilters, have been studied. The water content, electric resistance, transport number, distribution of grafting, thermal and chemical stability, and mechanical characteristics of the membranes were determined as a function of the grafting degree. Graft polymerization proceeds from both surfaces of the polymer film into the polymeric matrix depth. Cation-exchange membranes prepared possess good electrochemical and mechanical properties, high thermal and chemical stability at grafting degrees from 30 to 50%, and can be successfully used in electrodialysis processes. © 1993 John Wiley & Sons, Inc.     

Structure and properties of microporous membranes prepared by applying phase separation during polymerization

Porous membranes of poly(vinyl chloride) were obtained from cation exchange membranes prepared by the soaking and paste method, by selective decomposition of the cation exchange resin component. The structure and properties of the membranes as filters were investigated by scanning electron microscopy, infrared analysis, water permeability measurement, and determiantion of rejections for some solutes and dispersers with widely differing sizes. They completely rejected two kinds of bacteria and polymer particles with a diameter of about 0.1 μm. The rejection of hemoglobin ranged from 90 to 100%, depending upon the preparative conditions. Heat treatment of the cation exchange membranes increased water permeability of the resulting PVC porous membranes and decreased hemoglobin rejection in varying degrees, depending upon the treatment temperature.     

电泳膜接触器研究进展

电泳膜接触器（EMC）是在传统电渗析器中引入多孔膜,或用多孔膜代替部分离子交换膜的一种新型膜分离技术,其中多孔膜作为两液流的接触界面,提供传质的场所,垂直于液流方向的电场是唯一的驱动力。本文介绍了EMC的工作原理,并简要概述了EMC的膜堆构型及运行模式。详细分析了进料液pH值、电场强度等操作参数、多孔膜的材质和截留相对分子质量等对EMC过程传质的影响,且对EMC运行过程中多孔膜的污染状况进行了探讨,并展望了EMC在生物大分子分离和纯化中的应用潜力。EMC中多孔膜的引入,使得EMC可以用于相对分子质量大于500 Da的生物分子的分离与纯化,进一步拓宽了电渗析的应用领域,而外加电场的作用能够有效减轻多孔膜的污染,因此,EMC在生物分子的分离与纯化方面具有广阔的应用前景。