溶剂/非溶剂体系对聚醚砜微孔膜性能和结构的影响

以N,N-二甲基乙酰胺(DMAc)、N-甲基吡咯烷酮(NMP)和N,N-二甲基甲酰胺(DMF)为溶剂,乙醇(EtOH)、异丙醇(IPA)、正丁醇(BuOH)、一缩二乙二醇(DegOH)、聚乙二醇400(PEG400)为非溶剂添加剂,研究了溶剂/非溶剂体系对聚醚砜(PES)膜的结构和性能的影响.改变铸膜液体系中的非溶剂含量对膜的结构和性能有很大影响,但是这种影响不是以非溶剂的绝对含量来衡量的,而取决于非溶剂/溶剂的比值.改变溶剂的组成和配比也改变了溶剂/非溶剂体系,体系的溶度参数越接近PES的溶度参数,与PES的相容性越好,但是膜的通量较小.实验结果表明,采用NMP(或DMAc)与DMF以适当比例混合作溶剂,比采用单一NMP(或DMAc)作为溶剂制得的膜通量要大.通过改变溶剂配比,可实现对膜的表面开孔率、孔径、断面结构等参数的微控.     

聚醚砜/磺化聚醚醚酮共混膜的制备和性能

采用流延法制备了聚醚砜(PES)含量不同的PES/磺化聚醚醚酮(SPEEK)共混膜。PES与SPEEK具有良好的相容性。所制备PES/SPEEK共混膜的含水率、溶胀度和甲醇透过系数均随PES含量的增加而降低。虽然共混膜的质子传导性能有所降低.但阻醇性能和溶胀性能提高,这说明PES/SPEEK共混膜是一种很好的直接甲醇燃料电池用固体高分子电解质膜材料。     

聚(偏二氯乙烯-丙烯腈-甲基丙烯酸甲酯)对改性PVC超滤膜性能的影响

以N,N-二甲基乙酰胺(DMAc)为溶剂,讨论了聚(偏二氯乙烯-丙烯腈-甲基丙烯酸甲酯)(VAH)对聚氯乙烯(PVC)超滤膜性能的影响.当铸膜液中VAH含量为3％时,可得到渗透性能和截留率较好的超滤膜,其纯水通量达119x10-5 L/m2·h·Pa,截留率为84％.同时考察了芯液中溶剂含量对VAH含量为3％时的超滤膜性能的影响,当芯液中DMAc含量小于75％时,通量逐渐减小;当DMAc含量为95％时,通量急剧增大为162x10-5L/m2.h.Pa.     

SPEEK/PANI/PWA复合质子交换膜的制备及性能

为了解决Nafion膜甲醇渗透的问题,以聚醚醚酮(PEEK)、聚苯胺(PANI)和磷钨酸(PWA)为原料,采用流延制膜法制备了SPEEK/PANI/PWA复合质子交换膜,并通过X-射线衍射(XRD)、红外光谱分析(FT-IR)和扫描电子显微镜(SEM)等对其组织和结构进行了表征,利用紫外可见分光光度计、电化学工作站和气相色谱仪等对其性能进行了测试。研究结果表明,与SPEEK/PANI和SPEEK/PWA复合质子交换膜相比,SPEEK/PANI/PWA复合质子交换膜的综合性能有很大改善,可作为DMFC用质子交换膜。     

BaCe0.8Al0.2O3掺杂的SPEEK复合质子交换膜制备与性能1

针对普通磺化聚醚醚酮(SPEEK)膜质子传导率较低的问题,提出无机掺杂的改善方法.采用共沉淀法制备BaCe0.8Al0.2O3复合氧化物,将其掺杂到SPEEK膜基体中,并通过溶液浇铸法制得了SPEEK/BaCe0.8Al0.2O3复合质子交换膜.对复合膜的尺寸稳定性、氧化稳定性、力学性能、质子传导率及微观形貌等进行了测...     

磺化聚醚醚酮共混膜的制备及其特性的研究

通过溶液共混的方法,以磺化聚醚醚酮(SPEEK)和聚醚砜(PES)为原料,N,N-二甲基甲酰胺(DMF)为溶剂,制备了一系列不同比例的SPEEK与PES的共混膜,并研究了膜的组成对膜的吸水率、电导率、甲醇渗透系数的影响,与目前所使用的Nafion117膜相比,这种共混膜既可以提高阻醇性能,同时又具有一定的电导率。     

相转化法聚合物/溶剂/非溶剂铸膜体系的热力学计算

计算了相转化法铸膜体系中常见的典型三元相图,分析了聚合物与溶剂之间、聚合物与非溶剂之间、溶剂与非溶剂之间的相互作用参数对聚合物/溶剂/非溶剂铸膜液体系相图的影响,以及体系温度和聚合物摩尔体积对聚合物/溶剂/非溶剂铸膜液体系相图的影响。根据溶剂-非溶剂汽液平衡数据和溶解度参数得到了溶剂-非溶剂、溶剂与聚合物以及非溶剂与聚合物之间的Flory-Huggins相互作用参数,从而获得了几种常见铸膜液体系的相图。同时,利用聚合物/溶剂/非溶剂铸膜液体系的相图数据对热力学模型的参数进行了优化,取得了与实验结果较一致的计算结果。     

共混比及聚合物浓度对PVC/PVB相容性及超滤膜性能结构的影响

通过混合焓的计算,对不同共混比和聚合物浓度的聚氯乙烯(PVC)/聚乙烯醇缩丁醛(PVB)共混比体系的相容性进行预测,并通过稀溶液黏度(DSV)法、运动黏度法和目视法进行相应验证;以N,N-二甲基乙酰胺(DMAc)为溶剂,通过湿相转换法(NIPS)制备PVC/PVB共混平板超滤膜,并对超滤膜的性能和结构进行测试,系统地研究了PVC/PVB共混铸膜液的组成对平板超滤膜的结构及其分离性能的影响,为通过PVB共混改性PVC膜材料制备超滤膜提供了理论依据。     

质子交换膜燃料电池用磺化聚醚醚酮膜的研究进展

Nafion膜具有优良的化学稳定性和导电性能,但是它成本高,高温下几乎不导电。本文回顾了Nafion替代膜之一——磺化聚醚醚酮（SPEEK）膜及SPEEK/离子液体（IL）复合膜的研究进展。介绍了SPEEK制备的两种方法：直接磺化法和磺化单体聚合法,其中直接磺化法工艺简单,但磺化度（DS）≤1.0,反应较难控制;磺化单体聚合法DS可控,但工艺复杂,原料有毒。简述了温度、反应时间、原料配比、磺化单体种类、制膜工艺及溶剂对SPEEK膜性能的影响：直接磺化法中DS与温度成负相关,与反应时间成正相关,与原料配比关系不大;磺化单体聚合法中DS受磺化单体的种类和氟酮与磺化氟酮的比例影响较大。着重介绍了SPEEK/咪唑离子液体复合膜和SPEEK/季铵盐离子液体复合膜的研究现状及应用于质子交换膜燃料电池（PEMFC）时存在的问题。最后对SPEEK/IL复合膜未来的研究方向进行了展望,即解决燃料电池运行过程中复合膜中离子液体流失及与Pt基催化剂相容性等关键问题,以提高PEMFC的性能。     

聚合物膜的研制

以聚丙烯腈(PAN)／聚乙烯醇(PVA)合金为膜材料，用液-固相转化法成膜制备PAN/PVA体系的非对称型合金微滤膜。研究了铸膜液浓度、聚合物共混配比、铸膜液温度溶剂蒸发时间、凝胶浴温度对膜结构和膜性能的影响。结果表明：采用了液-固相转化法成膜，可制成孔径为0．5～5．0μm的非对称性PAN/PVA合金微滤膜。     

直接甲醇燃料电池用新型质子交换膜的研究

以聚醚醚酮(PEEK)为原料,浓硫酸为磺化剂制备了不同磺化度的磺化聚醚醚酮(SPEEK)膜,以及磺化聚醚醚酮与聚乙烯醇(PVA)、正硅酸乙酯(TEOS)、磷钨酸的复合膜.分别对膜的电导率、阻醇性能和吸水率进行了研究.随着SPEEK膜磺化度的增大,膜的电导率有所提高,然而甲醇渗透系数也增大,膜的机械强度明显降低.SPEEK膜的吸水率低于Nafion 115膜,而PVA膜的吸水率则过高.     

高质子传导率及尺寸稳定性复合质子交换膜制备及性能研究

通过2?丙烯酰胺?2?甲基丙磺酸（AMPS）在1种具有多孔结构的金属有机骨架（MOF）UiO?66?NH₂中聚合,获得UiO?66?NH₂/PAMPS杂化填料后将其加入磺化聚醚醚酮（SPEEK）中制备纳米复合质子交换膜,并对纳米填料和膜性能进行了测试和表征。其中,UiO?66?NH₂/PAMPS中MOF组分的有序孔洞能够为质子提供较为快速的传输通道,同时PAMPS组分上的磺酸基团则为这些通道提供了额外的质子传输位点,从而促进了复合膜中的质子传导。结果表明,填料与基体之间的强静电相互作用使复合膜的溶胀率有所下降;当填料含量达到6 %（质量分数,下同）时,复合膜的质子电导率（σ）从0.040 S/cm 提升到0.057 S/cm,比纯SPEEK高42.5 %,而溶胀率由29 %下降到23 %。     

Proton conducting blend membranes: physical,morphological and electronic properties

Blend membranes of sulfonated poly(ether ether ketone) (SPEEK) and sulfonated polyetherimide (SPEI) have been prepared and investigated as a potential polymer electrolyte membrane (PEM) for direct methanol fuel cell (DMFC). Polymers were dissolved in N-methyl-2-pyrrolidone (NMP) in different mixing ratios and membranes were casted using a semi-automatic casting machine on a pre-cleaned glass plate. The influence of SPEI percentage on ion exchange capacity (IEC), water uptake, methanol permeability and proton exchange capacity have been investigated. Blend membranes showed slightly better IEC, water uptake and methanol crossover properties as compare to pure SPEEK; but proton conductivity was slightly lower than that of pure SPEEK membrane. Membrane morphology was investigated by FESEM, TGA and AFM. Overall, a homogeneous surface was observed for most of the blend membranes, with minor phase separation at higher SPEI contents samples. AFM image of the membrane surface shows nanoscale surface roughness.     

Performance of the sulfonated poly ether ether ketone proton exchange membrane modified with sulfonated polystyrene and phosphotungstic acid for microbial fuel cell applications

In this research, the preparation of low cost proton exchange membranes (PEMs) based on sulfonated poly ether ether ketone (SPEEK) for application in the microbial fuel cells (MFCs) is studied. Sulfonated polystyrene (SPS) and phosphotungstic acid (PWA) were employed to improve the performance of PEM through the creation of more proton pathways. At first, the sulfonation of PEEK and polystyrene were performed through two modified methods to obtain uniform and high degree of sulfonation (DS) of the polymers and then, the PEMs were prepared through the solution casting method. Accordingly, the formation of uniform skin layer was confirmed by the SEM micrographs. Blending the aforementioned additives to the SPEEK polymer solution significantly enhanced the proton conductivity, water uptake and durability of the modified membranes. The proton conductivities of SPEEK/SPS and SPEEK/PWA membranes at additive/SPEEK weight ratio of 0.15 were 45.3% and 26.2% higher than that of the commercial Nafion117 membrane, respectively. Moreover, the degradation times for the abovementioned modified membranes were 140 and 350 min which indicated satisfactory oxidation stability. Besides, the aforementioned membranes exhibited two times more water uptake compared to the neat SPEEK membrane. Finally, SPEEK/SPS and SPEEK/PWA membranes produced 68% and 36% higher maximum power in the MFC, compared to the commercial Nafion117 membrane. Therefore, the fabricated PEMs are potentially suitable alternatives to be used in the fuel cell applications.     

Solution‐blown SPEEK/POSS nanofiber–nafion hybrid composite membranes for direct methanol fuel cells

This study aims to develop novel hybrid composite membranes (NHMs) by impregnating Nafion solution into the porous sulfonated poly(ether ether ketone)/polyhedral oligomeric silsesquioxanes (SPEEK/POSS) nanofibers (NFs). The composite membrane was prepared by solution blowing of a mixture of SPEEK/POSS solution. The characteristics of the SPEEK/POSS NFs and the NHMs, including morphology, thermal stability, and performance of membrane as PEMs, were investigated. The performance of NHMs was compared with that of Nafion117 and SPEEK/Nafion composite membranes. Results showed that the introduction of POSS improved the proton conductivity, water swelling, and methanol permeability of membranes. A maximum proton conductivity of 0.163 S cm^?1 was obtained when the POSS content was 6 wt % at 80°C, which was higher than that of Nafion117 and SPEEK/Nafion. NHMs could be used as proton exchange membranes (PEMs) for fuel cell applications. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42843.     

Modified Sulfonated Poly(ether ether ketone) Based Mixed Matrix Membranes for Direct Methanol Fuel Cells

Mixed matrix membranes based on zeolite 4A‐methane sulfonic acid (MSA)‐sulfonated poly(ether ether ketone) (SPEEK) are evaluated as a potential polymer electrolyte membrane (PEM) for direct methanol fuel cells (DMFCs). Ion‐exchange capacity, sorption of water, and water–methanol mixture, proton conductivity, and methanol permeability for the mixed‐matrix membranes have been extensively investigated. The mixed‐matrix membranes are also characterized for their cross‐sectional morphology, mechanical, and thermal properties. DMFCs employing SPEEK‐MSA (20 wt.%) blend, zeolite 4A (4 wt.%)‐SPEEK‐MSA (20 wt.%) mixed matrix membranes deliver peak power densities of 130 and 159 mW cm^–2, respectively; while a peak power density of only 95 mW cm^–2 is obtained for the DMFC employing pristine SPEEK membrane at 70 °C. The results showed that these SPEEK based mixed matrix membranes exhibit higher DMFC performance and lower methanol permeability in comparison to Nafion‐117 membrane.     

Sulfonated poly(ether ether ketone)/epoxy/phenol novolac blend proton‐exchange membranes with low methanol permeability

A crosslinked epoxy [4,4′‐diglycidyl‐(3,3′,5,5′‐tetramethylbiphenyl) epoxy resin (TMBP)], cured by phenol novolac (PN), was introduced into a sulfonated poly(ether ether ketone) (SPEEK) membrane (ion‐exchange capacity = 2.0 mequiv/g) with a casting‐solution, evaporation, and heating crosslinking method to improve the mechanical properties, dimensional stability, water retention, and methanol resistance. By Fourier transform infrared analysis, the interactions between the sulfonic acid groups and hydroxyl groups in the blend membranes were confirmed. The microstructure and morphology of the blend membranes were investigated with atomic force microscopy. As expected, the blend membranes showed excellent mechanical properties, good thermal properties (thermal stability above 200°C), lower swelling ratios (1.4% at 25°C and 7.0% at 80°C), higher water retention (water diffusion coefficient = 9.8 × 10^?6 cm²/s), and a lower methanol permeability coefficient (3.6 × 10^?8 cm²/s) than the pristine SPEEK membrane. Although the proton conductivity of the blend membranes decreased, a higher selectivity (ratio of the proton conductivity to the methanol permeability) was obtained than that of the pristine SPEEK membrane. The results showed that the SPEEK/TMBP/PN blend membranes could have potential use as proton‐exchange membranes in direct methanol fuel cells. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

DMFCs用磺化聚醚醚酮/磺化酚酞型聚醚砜共混质子交换膜

A sulfonated poly(ether ether ketone) (SPEEK) membrane with fairly high degree of sulfonation (DS) swells excessively and even dissolves at high temperature. To solve these problems, sulfonated phenolphthalein poly(ether sulfone) (SPES-C, DS 53.7%) is blended with the SPEEK matrix (DS 55.1%, 61.7%) to prepare SPEEK/SPES-C blend membrane. The decrease in swelling degree and methanol permeability of the membrane is dose-dependent. Pure SPEEK (DS 61.7%) membrane dissolves completely in water at 70ºC, whereas the swelling degree of the SPEEK (DS 61.7%)/SPES-C (40%, by mass) membrane is 29.7% at 80ºC. From room temperature to 80ºC, the methanol permeability of all SPEEK (DS 55.1%)/SPES-C blend membranes is about one order of magnitude lower than that of Nafion®115. At higher temperature, the addition of SPES-C polymer increases the dimensional stability and greater proton conductivity can be achieved. The SPEEK (DS 55.1%)/SPES-C (40%, by mass) membrane can withstand temperatures up to 150ºC. The proton conductivity of SPEEK (DS 55.1%)/SPES-C (30%, by mass) membrane approaches 0.16 S•cm－1, matching that of Nafion115 at 140ºC and 100% RH, while pure SPEEK (DS 55.1%) membrane dissolves at 90ºC. The SPEEK/SPES-C blend membranes are promising for use in direct methanol fuel cells because of their good dimensional stability, high proton conductivity, and low methanol permeability.     

全钒液流电池用SPEEK／PES共混膜的制备

通过将PES掺入高磺化度的SPEEK进行共混改性,采用流延法制备了一系列不同PES含量的SPEEK／PES共混膜,获得了SPEEK／PES共混膜的离子交换容、含水率、质子电导率等参数,特别测定了在全钒液流电池工作条件下钒（IV）离子渗透率。综合考察发现,当磺化温度为45℃,磺化时间控制为4h,得到SPEEK的DS为55％,掺入10％的PES,此时共混膜的电导率为0．08S／cm,钒（IV）离子渗透率为0．38×10^-6cm2／min,对钒（IV）离子选择性为Nation膜的5倍,含水率为35％,共混膜综合性能最好,基本满足全钒液流电池（VRB）的使用需求。     

Effect of dispersion state of Cloisite15A® on the performance of SPEEK/Cloisite15A nanocomposite membrane for DMFC application

The introduction of 2,4,6‐triaminopyrimidine (TAP) into sulfonated poly(ether ether ketone) (SPEEK)/Cloisite15A® nanocomposite membranes were investigated for the purpose of maintaining low methanol permeability and suppressing swelling in direct methanol fuel cell (DMFC). SPEEK with 63% of degree of sulfonation (DS) was prepared by sulfonation of PEEK. Cloisite15A (7.5 wt %) along with various weight loading of TAP was incorporated into SPEEK matrix via solution intercalation method. The effect of TAP loading on the SPEEK/Cloisite15A/TAP morphology was studied. The beneficial impact of the SPEEK/Cloisite15A/TAP morphology on the physicochemical properties of the membrane was further discussed. Swelling behavior, ion exchange capacity (IEC), proton conductivity, and methanol permeability of the resultant membranes were determined as a function of Cloisite15A and TAP loadings. Uniform distribution of Cloisite15A particles in the SPEEK polymer matrix in the homogenous SPEEK/Cloisite15A/TAP nanocomposite membranes was confirmed by scanning electron microscopy and X‐ray diffraction. The water uptake of the SPEEK nanocomposite membranes decreased dramatically in the presence of TAP. The significant selectivity of SP/7.5/7.5 nanocomposite membranes could indicate a potential feasibility as a promising electrolyte for DMFC. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012