杂萘联苯聚芳醚质子交换膜材料的研究

质子交换膜是质子交换膜燃料电池的核心部件之一，其性能的优劣直接关系燃料电池的工作性能。目前质子交换膜燃料电池多采用全氟磺酸离子膜，全氟磺酸膜虽然具有较高的质子传导性和良好的化学稳定性，但是也具有价格昂贵、甲醇渗透高和高温下质子传导性能下降等缺点。为了克服全氟磺酸膜的不足，国内外相继开展了非氟质子交换膜的研究，如磺化聚醚醚酮（SPEEK）、磺化聚醚醚酮酮（SPEEKK）、磺化聚砜（SPSU）和磺化聚酰亚胺（SPI）等。     

侧链磺化型聚砜质子交换膜的设计与制备及其性能研究

在制备氯甲基化聚砜(CMPSF)的基础上,以对羟基苯磺酸钠(HBSS)和羟基苯二磺酸钠(HBDSS)为亲核试剂,通过亲核取代反应,在聚砜(PSF)主链上分别键联了以苯磺酸根(BSS)和苯二磺酸根(BDSS)基团为末端基的侧链,制得了亲水磺酸根基团与疏水主链"微相分离"结构的2种侧链型磺化聚砜PSF-BSS和PSF-BDSS,并优化了制备条件.在对磺化聚砜产物进行充分表征(FTIR和1H-NMR谱)的基础上,采用流延成膜法制备了质子交换膜,测定了质子交换膜的基本性能,重点考察了质子交换膜"芳香性"主链和亲疏水微区"相分离"这2种结构因素对交换膜性能的影响.实验结果表明,在极性较强的溶剂中,CMPSF与羟基苯磺酸钠可顺利地发生亲核取代反应,于100℃经40 h反应可制得磺酸根键合量分别为2.07 mmol/g和2.11 mmol/g的磺化聚砜PSF-BSS和PSF-BDSS.所制备的质子交换薄膜具有较高的质子传导率(PSF-BDSS交换膜室温为4.7×10-2S/cm,80℃为8.1×10-2S/cm),优良的尺寸稳定性(室温溶胀率为8.6%,80℃溶胀率为30%),且具有良好的热稳定性与抗氧化稳定性.     

萘磺酸型侧链磺化聚砜质子交换膜的性能

以聚砜(PS)和自制的1,4-二氯甲氧基丁烷(BCD)为氯甲基化试剂通过Fridel-Crafts烷基反应制备氯甲基化聚砜(CPS),紧接着氯甲基与2-萘酚-6,8-二磺酸钾(NSK)试剂通过亲核取代反应制备一种萘磺酸型磺化聚砜(PS-NS),在用红外和核磁氢谱充分表征的基础上制备一系列磺酸基团键合量不同的PS-NS质子交换膜(分别为PS-NS-1,PS-NS-2,PS-NS-3)重点研究温度对质子交换膜性能的影响规律。研究结果表明:由于亲水基团与疏水主链距离较远,能够形成类似于Nafion膜的微相分离结构,使得该质子交换膜在高磺化度下仍能保持高的尺寸稳定性,同时随着温度升高,质子交换膜的吸水率、溶胀性以及质子传导率增加,PS-NS-3在25℃和85℃的吸水率为21. 3%和42. 7%,但是溶胀率仅为22. 2%和50. 3%,与商业化Nafion115膜(24. 9%和55. 0%)的性能十分接近,表现出很好的尺寸稳定性。     

静电纺丝纳米纤维在燃料电池质子交换膜中应用的研究进展

保护环境,开发环保型能源,对人类和社会具有重要意义。 质子交换膜燃料电池由于具有燃料转化率较高和无污染的优点,备受关注。 静电纺丝纳米纤维具有比表面积大、高孔隙率和三维的相互连通的网状结构等特点,可以在燃料电池质子交换膜中得到广泛应用。 静电纺丝纳米纤维类复合质子交换膜具有较高的质子传导率,较低的燃料渗透率,较好的化学稳定性能、热稳定性能和机械性能。 本文首先介绍了质子交换膜燃料电池,然后从不同的离子型聚合物基质复合质子交换膜的类别出发,介绍了静电纺丝纳米纤维在Nafion、磺化聚酰亚胺(SPI)、聚苯并咪唑(PBI)、磺化聚醚醚酮(SPEEK)等不同种类的离子型聚合物质子交换膜中的研究现状及作用机理,同时对静电纺丝纳米纤维在质子交换膜的应用方面存在的问题及应用前景做了评论和展望。     

侧链结构对侧链型磺化聚砜质子交换膜性能的影响

以双酚A型聚砜(PS)为基础,与自制的1,4-二氯甲氧基丁烷反应制备氯甲基化聚砜(CPS),接着与2-萘酚-6,8-二磺酸钾(NSK)进行亲核取代反应制备萘磺酸型侧链磺化聚砜(PS-NS)。采用溶液浇注法制备相应的质子交换膜(PEMs),结合前期研究的脂肪磺酸型侧链磺化聚砜(PS-ES)和苯磺酸型侧链磺化聚砜(PS-BS) PEMs,考察侧链结构对PEMs的吸水率、吸水溶胀率和尺寸稳定性的影响关系。结果表明,与主链型芳香聚合物PEMs相比,3种侧链型磺化聚砜PEMs由于亲水基团远离疏水主链,能够形成类似于Nafion膜的相分离结构,在高吸水率下保持更好的尺寸稳定性;在相同的离子交换膜容量(IEC)下,PS-ES、PS-BS和PS-NS膜随着侧链刚性苯环数目的增加,侧链的运动能力减弱,导致PEMs的尺寸稳定性增加,相应的质子传导率减小; PS-ES膜在25℃和85℃的质子传导率分别达到0. 072和0. 141 S/cm,PS-NS在25℃和85℃的尺寸溶胀性仅为21. 8%和51. 5%,性能与商业化的Nafion115膜十分接近。     

磺化聚醚醚酮与壳聚糖共混制备直接甲醇燃料电池用质子交换膜

给出了不同磺化度下的磺化聚醚醚酮(SPEEK)用作质子交换膜的一系列性能,另外提出了一种新型的酸碱共混质子交换膜,其中,磺化聚醚醚酮和壳聚糖分别被选为酸性、碱性高分子电解质,并对所制备的质子交换膜的相关性能如质子传导性,甲醇渗透性,吸水率以及膜溶胀性、热稳定性等进行了表征,结果表明此种新型复合膜尽管在质子传导性能方面有所下降,阻醇性能改变不大,但是膜溶胀性和吸水率方面有了较大的改善.磺化度为71.4%的SPEEK与壳聚糖以5∶1摩尔比共混制备的质子交换膜,其性质可以与商品化的Nafion 117相媲美,有望在甲醇燃料电池中得到应用.     

燃料电池用聚合物质子交换膜专利技术分析

聚合物质子交换膜是燃料电池的一个重要组成部分,也是目前研究的热点技术。本文对燃料电池用聚合物质子交换膜领域的专利申请状况进行了分析,从全氟型磺化聚合物质子交换膜、部分含氟型磺化聚合物质子交换膜和非含氟型磺化聚合物质子交换膜等3个方面出发,归纳出该技术领域的技术发展路线,并对该技术领域的发展做出展望。     

侧链型磺化聚砜质子交换膜构-效关系的研究

在制备氯乙酰基化聚砜(CAPS)和氯丁酰基化聚砜(CBPS)的基础上,以对羟基苯磺酸钠(HBS)为试剂,通过亲核取代反应制备侧链长度不同的两种侧链型磺化聚砜2PS-BS和4PS-BS (侧链碳原子数目分别是2和4),利用FT-IR和1H-NMR表征它们的化学结构后,采用溶液浇注法制备它们的质子交换膜(PEM),同时结合我们前期制备的侧链型磺化聚砜1PS-BS质子交换膜,研究柔性侧链的长度对PEM性能的影响。研究结果显示,与主链型PEM相比,1PS-BS、2PS-BS和4PS-BS由于亲水基团远离疏水主链,能够形成类似于Nafion膜的相分离结构,相应的PEM在高吸水率下仍能保持优越的尺寸稳定性和耐氧化性能。在相同的温度和IEC下,3种PEM随着柔性侧链长度的增加,PEM的相分离程度增强,进而导致PEM的尺寸稳定性、耐氧化性能和质子传导率增强,其中4PS-BS-4膜在25℃时的吸水溶胀性仅为7.1%,优于相同条件下Nafion115和Nafion117膜(室温溶胀率分别为9.5%和11%),相应的质子传导率达到了0.049S/cm,满足燃料电池的实际应用要求。     

磺化杂萘联苯聚醚酮酮醚酮质子交换膜材料的合成与表征

以1,4-二(3-磺酸钠-4-氟代苯甲酰基)苯(SBFBB)和4,4’-二氟二苯酮(DFK)为二卤单体,与杂萘联苯类双酚进行溶液亲核缩聚反应,通过调控SBFBB与DFK的比例,制备了一系列具有不同磺化度的高分子量磺化杂萘联苯聚醚酮酮醚酮(SPPEKKEKs)。采用红外光谱、核磁共振谱、示差扫描量热分析等对SPPEKKEKs的结构和性能进行了表征,随着磺化度增加,SPPEKKEKs的玻璃化转变温度增大。以氮甲基吡咯烷酮为溶剂制备质子交换膜,随着SPPEKKEKs的磺化度增加,质子交换膜的含水率和质子传导率增加,95℃时,质子交换膜的质子传导率均达到10-2S.cm-1,SPPEKKEKs质子交换膜具有较好的耐氧化性能。     

基于一锅法的磺化聚砜质子交换膜的性能

以双酚A型聚砜(PSF)为基质材料,通过傅-克烷基化反应在PSF主链引入—NCO活性基团,制备乙基异氰酸化聚砜(PS-SA)。 在制备PS-SA的基础上,采用两步一锅法,PS-SA与2-萘酚-6,8-二磺酸钾通过亲核取代反应,制备一种侧链含有萘环的萘磺酸型磺化聚砜PS-NS,充分表征聚合物的化学结构,以溶液浇注的方法制备质子交换膜,研究了温度对PS-NS膜的吸水率(WU,Water Uptaking)、吸水溶胀性(Swelling Ratio)、质子传导率(Proton Conductivity)等基本性能的影响。 结果表明,PS-NS膜由于亲水基团距离较远,能够很容易形成相分离结构,所制备的质子交换膜高WU下尺寸稳定性仍然很高,其中PS-NS-4膜(磺酸基团键合量为1.42 mmol/g)在25和85 ℃的WU高达27.2%和40.3%,但是相应的吸水溶胀性仅为25.2%和57.2%,与相同条件下Nafion115膜的性能十分接近。     

Preparation and characterizations of asymmetric sulfonated polysulfone membranes by wet phase inversion method

This paper presents an original approach to prepare the asymmetric sulfonated polysulfone membranes by using wet phase inversion method and their applications for dehydrating a water/ethanol mixture by pervaporation. The separation performances of sulfonated membranes were strongly affected by the degree of sulfonation and the degree of swelling of membranes. The substitution degree of sulfonic group enhanced the permselectivity of sulfonated polysulfone membranes by increasing the hydrophilicity of polymer backbone. Based on the observations of membrane morphology and light transmittance measurements, the degree of sulfonation of polysulfone presented less influence on the membrane formation pathway and the final structure of membrane in wet phase inversion process. It was also found that the sulfonated membranes showed well hydrophilic properties and facilitated water adsorption in the membranes. The sorption and permeation properties also showed that the permselectivity of asymmetric membrane was dominated by the permeate diffusion rather than the permeate sorption in the skin layer. The high separation performance of pervaporation membrane can be achieved by phase inverse method with sulfonated polysulfone.     

Pervaporation separation of water/ethanol mixture by sulfonated polysulfone membrane

For dehydrating a water/ethanol mixture by pervaporation, a sulfonated polysulfone membrane was prepared. The separation performance of water and ethanol are shown to strongly depend on the degree of substitution of polysulfone membrane. The degree of substitution increased with increasing chlorosulfonic acid in the casting solution, and the substitution reaction was achieved within 2 h. The water permeation rate and separation factor increased with increasing substitution of polysulfone membrane up to a substitution of 2.0. The effect of sulfonation on separation performance was due to the improvement of hydrophilicity of sulfonated membrane. It was found that the solubility of water/ethanol in the membrane was not the dominant factor for separation but it was rather the diffusion difference in the membrane. The diffusion difference between permeate through sulfonated membrane was the dominant factor for separating the water/ethanol mixture. The high performance of pervaporation membrane can be prepared by sulfonated polysulfone.     

Sulfonated hydrocarbon graft architectures for cation exchange membranes

A synthetic strategy to hydrocarbon graft architectures prepared from a commercial polysulfone and aimed as ion exchange membrane material is proposed. Polystyrene is grafted from a polysulfone macroinitiator by atom transfer radical polymerization, and subsequently sulfonated with acetyl sulfate to various degrees. Series of grafting densities and graft lengths are prepared, and membranes are solvent cast from DMSO. The membrane properties in aqueous environments are evaluated from their water swelling behavior, and their thermal properties and stability are investigated by thermogravimetric analysis and differential scanning calorimetry.     

Hydraulic permeation of NaCl solution through sulfonated polysulfone-polyvinyl alcohol polysulfone composite reverse osmosis membrane

The hydraulic permeation of NaCl solution through sulfonated polysulfone-polyvinyl alcohol/polysulfone composite reverse osmosis membrane was systematically investigated. It was found that the transport of water in a sulfonated polysulfone-polyvinyl alcohol/polysulfone composite reverse osmosis membrane follows the modified solution diffusion equation developed by Yang and Chu. Moreover, the equation between salt rejection and applied pressure was proposed for describing the hydraulic permeation of salt solution through a sulfonated polysulfone-polyvinyl alcohol/polysulfone composite membrane. The salt rejection was found to fit the greater part of separation transport mechanism. The experimental data and the salt rejection equation appear to be in excellent agreement.     

磺化聚砜改性超滤膜的制备及性能

溶剂萃取过程的乳化现象是影响萃取率和产品质量主要问题,长期以来一直靠破乳剂解决,这会造成环境污染等问题[1,2]。膜分离技术能耗低、对具有生物活性的物质能保持其活性、分离产物易于回收,在抗生素提炼中的应用研究近年来十分活跃[3 5]。本文以磺化聚砜为膜材料、N,N 二甲基酰胺为溶剂,采用多元复合添加剂,用湿法相转移化法制备出孔径为400-500 、具有指孔状或海绵状结构的磺化聚砜改性超滤膜,作为抗生素提炼的分离膜。1　实验部分1 1　主要仪器及试剂扫描电镜(S 250,英国Cambridge公司);离子活度计(PXS 215,上海分析仪器厂)。聚…     

脱溶剂速度对聚砜/磺化聚砜合金膜结构和性能的影响

介绍了铸膜液温度、成膜过程中的蒸发时间、环境湿度、凝胶浴温度对聚砜/磺化聚砜合金膜的渗透、分离性能的影响.随环境相对湿度、凝胶浴温度增大,合金膜的水通量增大,截留率下降;蒸发时间延长,合金膜的水通量通过一个极大值,截留率呈现下降趋势.     

A Comparative Study of the Electric Transport of Ions and Water in Sulfonated Cation-Exchange Polymeric Membranes of the New Generation

This work presents the results of the studies concerning the electric transport of ions and water through sulfonated cation-exchange membranes synthesized on the basis of polysulfone (PS) and poly(ether–ether–ketone) (PEEK). The concentration dependences of the water absorption capacity, specific conductance, and diffusion and electroosmotic permeabilities measured in sodium chloride solutions are compared to the analogous characteristics of some commercial membranes (MK-40, MF-4SK, CL-25T) under the same experimental conditions. The model concepts concerning the permeability of ion-conducting membranes as disperse systems are found to be applicable for interpreting the set of the electric transport properties of the membrane samples studied. A cluster–channel type of the membrane structure is identified. The polymeric films based on PS and PEEK are shown to possess characteristics comparable to those of commercial ion-exchange membrane samples and can be recommended for producing polymer compositions with an optimum set of electric transport properties.     

Preparation of composite hollow fiber membranes: co-extrusion of hydrophilic coatings onto porous hydrophobic support structures

Coating a layer onto a support membrane can serve as a means of surface functionalization of membranes. Frequently, this procedure is a two-step process. In this paper, we describe a concept of membrane preparation in which a coating layer forms in situ onto a support membrane in one step by a co-extrusion process. Our aim is to apply a thin ion exchange layer (sulfonated polyethersulfone, SPES) onto a polysulfone support. The mechanical stability and adhesion of the ion-exchange material to the hydrophobic support membrane (polysulfone) has been studied by a systematic approach of initial proof-of-principle experiments, followed by single layer and double-layer flat sheet casting. Critical parameters quantified by the latter experiments are translated into the co-extrusion spinning process. The composite hollow fiber membrane has low flux as a supported liquid membrane for the copper removal due to the low ion exchange capacity of the SPES. The coating layer of the composite membrane is porous as indicated by gas pair selectivity close to unity. However, our new composite membrane has good nanofiltration properties: it passes mono and bivalent inorganic salts but rejects larger charged organic molecules. The experimental work demonstrates that co-extrusion can be a viable process to continuously prepare surface tailored hollow fiber membranes in a one-step process, even if the support and coating material differ significantly in hydrophilicity.     

Polyurethane and sulfonated polysulfone blend ultrafiltration membranes. I. Preparation and characterization studies

Polyurethane (ether type) and sulfonated polysulfone (sodium salt form) in the presence of polyethylene glycol 600 were blended in various compositions using N,N'-dimethylformamide as solvent and used for preparing ultrafiltration membranes by the phase inversion technique. Polymer blend composition, additive concentration, and casting and gelation conditions were optimized. Blend membranes were subjected to ultrafiltration characterizations such as compaction, pure water flux, water content, and membrane resistance. The membranes were also subjected to the determination of pore statistics and molecular weight cutoff determination studies using dextran of different molecular weights. Surface morphology of the membranes was analyzed using scanning electron microscopy at different magnifications. The effects of polymer composition and additive concentration on the above parameters were analyzed and the results are compared and discussed with those of pure sulfonated polysulfone membranes. The derived pore size, porosity, and number of pores have a remarkable interrelationship and also have a definite role and relationship with the molecular weight cutoff, morphology, and flux performance of the membranes.     

Sulfophenylation of Polysulfones for Proton‐Conducting Fuel Cell Membranes

Polysulfone has been sulfophenylated by lithiation and anionic reaction with 2‐sulfobenzoic acid cyclic anhydride. This provides a new convenient method to modify polysulfones by attaching pendant sulfonated phenyl groups via ketone links. Membranes of the sulfophenylated polysulfones show promise for use in proton‐exchange‐membrane fuel cells. For example, a membrane with 0.9 sulfophenyl units per repeating polysulfone unit and 30 wt.‐% water was found to have a proton conductivity of 32 mS/cm at 60°C.