SPTES-b-PI质子交换膜的制备及表征

质子交换膜作为质子交换膜燃料电池的核心部件具有提供离子通道传递质子和隔绝两极气体的双重作用,其性能的好坏直接影响着电池性能的优劣。主链引入亲水和疏水段的嵌段芳香族共聚物,由于各嵌段之间具有热力学不相容性会产生微相分离结构,进而形成高效的质子传导通道。本文以磺化双（4-氟苯基）砜（SDFDPS）和4,4'-硫代双苯硫酚（TBBT）为单体,以间羟基苯胺为封端剂合成了带有氨端基的磺化聚芳硫醚砜（SPTES-NH₂）。嵌段聚合物SPTES-b-PI通过亲水段SPTES-NH₂与以1,4,5,8-萘四羧酸二酐（NDA）和4,4'-双（3-氨基苯氧基）二苯基砜（m-BAPS）为单体缩聚而成的疏水段聚酰亚胺（PI）的酰亚胺化偶联反应来合成,制备出了PI分子量不同的SPTES-b-PIx（x=5~20kg/mol）。SPTES-b-PIx膜显示出优异的热力学稳定性,SPTES-b-PIx膜的脱磺化反应开始于290℃高于260℃的SPTES膜,与SPTES-70相比吸水率降低。随着聚酰亚胺分子量的增大,热稳定性增加,质子传导率增加。SPTES-b-PIx的质子传导率25℃下达到0.045~0.124S/cm。     

磺化聚苯并咪唑/磺化聚醚砜酸碱复合质子交换膜的制备与表征

为提高膜的尺寸稳定性和阻醇性能,以磺化聚苯并咪唑(S-PBI)与高磺化度聚醚砜(ABPS)两种聚合物为原料,采用溶液共混的方法,制备了系列酸碱复合质子交换膜。研究了复合膜的甲醇溶胀性、吸水率、甲醇渗透系数、质子传导率随S-PBI含量的变化规律。研究表明,随着S-PBI含量的增加,膜的阻醇性能和尺寸稳定性明显提高;同时,复合膜具有较好的质子传导率,有望应用于直接甲醇燃料电池。     

DMFC用磺化聚酰亚胺质子交换膜的合成与性能

以一种磺化二胺单体2,2′-二磺酸基-4,4′-二苯醚二胺(S-ODA)与非磺化单体4,4′-二苯醚二胺(ODA),及二酐单体3,3′,4,4′-二苯甲酮四羧酸二酐(BTDA)为原料,采用高温一步法直接聚合,得到了一系列磺化聚酰亚胺(SPI)质子交换膜材料,并用红外光谱对聚合物进行了表征.通过改变聚合体系中磺化单体与非磺化单体的比例控制聚合物的磺化度,并研究了材料的组成对膜的电导率、吸水率等性能的影响。     

3,3'-二磺化-4,4'-二氟二苯砜二钠盐的合成与表征

以工业级4,4'-二氟二苯砜(DFDPS)为原料,利用升华方法进行纯化处理后,采用发烟硫酸直接磺化,通过改变反应物计量比、反应温度、反应时间等参数,系统研究了3,3'-二磺化-4,4'-二氟二苯砜二钠盐(SDFDPS)的制备方法.采用HPLC、UV、~1H NMR 及FTIR对磺化产物结构及纯度进行了表征,由此得到最佳的磺化条件为:反应物摩尔比(SO_3∶DFDPS)为3.0∶1,在110℃下反应20 h.在此反应条件下的磺化产物中未发现单磺化产物以及未磺化的原料DFDPS.经过乙醇/水两次重结晶后,总收率达到75%.以合成的SDFDPS为原料合成了磺化度60%的磺化聚芳醚砜聚合物,该聚合物具有较高的相对黏度,同样也表明了SDFDPS的高纯度.     

磺化聚砜/黑磷复合质子交换膜制备及性能研究

以聚醚砜(PES)为原料，采用氯磺酸(CSA)为磺化剂，通过控制反应温度和时间制备系列磺化聚砜(SPES)，并以SPES为基质，二维黑磷(BP)为功能填料，采用溶液铸膜法制备了复合质子交换膜。采用红外光谱分析仪(FTIR)、X射线衍射仪(XRD)、扫描电子显微镜(SEM)等对材料结构进行表征，研究了复合膜的吸水率、质子交换性、阻醇性等。结果表明，SPES的磺化度随反应温度、时间、磺化剂浓度的升高而增大。BP的添加增强了复合膜的热稳定性、氧化稳定性、质子交换性、阻醇性等综合性能。在相同测试条件下SPES基膜的甲醇渗透率为1.185×10^-6 cm²/s，而5%(质量分数，下同)SPES/BP复合膜的甲醇渗透率仅为2.88×10^-7 cm²/s。     

含氟磺化聚芳醚酮质子交换膜的制备与性能研究

以六氟双酚A(6FBPA),4,4′-二氟二苯酮(DFBP)和3,3′-二磺酸钠基-4,4′-二氟二苯酮(SDFBP)为单体,调整单体DFBP与SDFBP的摩尔投料比,通过缩合共聚反应合成了一系列离子交换容量不同的含氟磺化聚芳醚酮共聚物(SPEK-6Fs)。采用红外(FT-IR)、核磁共振氢谱(1H-NMR)对共聚物的结构进行了表征,同时对所制备的质子交换膜的吸水率、尺寸稳定性、甲醇透过率、质子电导率及抗氧化性能等进行了一个综合的评价。结果表明:所合成的聚合物具有较高的分子量,可通过溶液浇铸成膜法制备成柔韧、透明的膜,所制备的膜具有良好的尺寸稳定性,在同等测试条件下,具有与杜邦公司Nafion 117膜相当的质子电导率,同时,其甲醇渗透率比Nafion 117膜低1~2个数量级。     

车用燃料电池质子交换膜的制备及性能

合成了一系列具有不同支化度的磺化聚芳醚砜材料,并对其结构和性能进行了表征。所制备的磺化的支化聚芳醚砜材料的分子量可达7.00×105以上,并且分子量分布在1.17左右,拉伸强度可达20.55~28.81 MPa。随着聚合物支化度的增加,聚合物的热稳定性得到改善,在550℃下的热失重可降低至39%~45%。高支化的磺化聚芳醚砜薄膜的氧化稳定性也得到改善,80℃下的使用寿命可提高至7.25 h。支化的磺化聚芳醚砜薄膜的吸水率和质子传导率都较高。80℃下高支化度的聚芳醚砜薄膜的质子传导率可达0.33 S/cm。对其微观形貌进行观测发现,支化聚芳醚砜中的支化结构可对周围的亲水磺酸基团起支撑作用,促使其发生团聚而形成连续的质子通道。     

聚丙烯腈/磺化聚苯醚质子交换膜的制备和性能

采用溶液共混浇铸法制备了一系列的聚丙烯腈/磺化聚苯醚(PAN/SPPO)共混质子交换膜.结果表明,磺酸基团成功引入交换膜,共混膜有较好的相容性,没产生相分离,PAN/SPPO共混膜的吸水率和溶胀率明显降低,其热性能稳定.与纯SPPO膜相比,虽然英质子传导率有所下降,但都在10-2～ 10-3S/cm数量级范围内,究全可...     

3,3′-二磺化-4,4′-二氟二苯砜二钠盐的合成与表征

以工业级4,4′-二氟二苯砜(DFDPS)为原料,利用升华方法进行纯化处理后,采用发烟硫酸直接磺化,通过改变反应物计量比、反应温度、反应时间等参数,系统研究了3,3′-二磺化-4,4′-二氟二苯砜二钠盐(SDFDPS)的制备方法。采用HPLC、UV、¹H NMR 及FTIR对磺化产物结构及纯度进行了表征,由此得到最佳的磺化条件为：反应物摩尔比(SO₃∶DFDPS)为3.0∶1,在110℃下反应20 h。在此反应条件下的磺化产物中未发现单磺化产物以及未磺化的原料DFDPS。经过乙醇/水两次重结晶后,总收率达到75%。以合成的SDFDPS为原料合成了磺化度60%的磺化聚芳醚砜聚合物,该聚合物具有较高的相对黏度,同样也表明了SDFDPS的高纯度。     

含氟聚醚砜阴离子交换膜的制备及其性能测定

以双(4-氯苯基)砜和2,2-双(4-羟基苯基)六氟丙烷为单体,通过缩聚反应、氯甲基化、季铵化和碱化,制备了一系列阴离子交换膜。利用核磁共振氢谱对聚醚砜、氯甲基化聚醚砜和季铵化聚醚砜的结构进行了表征,测试了上述系列交换膜的离子交换容量、吸水率、溶胀率、质子传导率、拉伸强度及化学稳定性等多项性能。结果表明,上述系列膜中,QPES-A5膜性能最佳,膜的离子交换容量(IEC)为1.739 meq/g,80℃下吸水率达45.4%,溶胀率为20.6%,质子传导率为26.10 mS/cm,拉伸强度为24 MPa。60℃时,采用3 mol/L NaOH溶液浸泡24 h,质子传导率仍为21.90 mS/cm,说明该膜具有良好的化学稳定性。     

Sulfonated poly(arylene ether sulfone) membranes based on biphenol for direct methanol fuel cells

A series of sulfonated poly(arylene ether sulfone) (PAES) were synthesized through direct aromatic nucleophilic substitution polycondensation of 3,3′-disulfonate-4,4′-dichlorodiphenylsulfone (SDCDPS), 4,4-dichlorodiphenylsulfone (DCDPS) and 4,4-biphenol (BP). With increasing sulfonate groups in the polymer, water uptake, ion exchange capacity (IEC) and proton conductivities increased, resulting from enhanced membrane hydrophilicity. The membranes exhibited higher thermal stability up to 300 °C, verified by thermogravimetric analysis (TGA). A maximum proton conductivity of 0.11 S/cm at 50 mol% of sulfonation degree was measured at 30 °C, which is slightly higher than Nafion®117 membrane (0.0908 S/cm). However, the methanol permeability of the PAES membrane was much lower than that of Nafion®117 membrane. As a result, a single cell performance test demonstrated that PAES-BP with 50 mol% sulfonation degree exhibited higher power density than Nafion®117.     

一种新型磺化聚酰亚胺质子交换膜的合成与表征

质子交换膜是质子交换膜燃料电池膜电极的核心部件之一,它的性能好坏对整个系统的运行起着至关重要的作用．目前在质子交换膜燃料电池中普遍采用的质子交换膜材料是全氟磺酸系列薄膜,这类材料具有较高的质子传导率、化学及机械稳定性,但用于直接甲醇燃料电池（DMFC）时则存在甲醇渗透、导致燃料电池输出性能大大降低的问题     

Composite Proton Exchange Membranes of Sulfonated Poly(ether ketone ether sulfone) (S-PEKES) and Molecular Sieve With High Mechanical Strength for Direct Methanol Fuel Cell

Composite proton exchange membranes are prepared by solvent casting via the incorporation of molecular sieves 3A, 4A, and 5A into the sulfonated poly(ether ketone ether sulfone) (S-PEKES) at the sulfonation degree of 0.66, with varying the ratio at of 3%, 6%, 9%, and 12% v/v. The influences of type and amount of the molecular sieves on the proton conductivity, methanol permeability, structural, thermal, and mechanical stabilities of the membranes are investigated. The composite membranes are characterized by FTIR, TGA, LCR meter, and GC techniques. All properties of the composite membrane are compared with the pristine S-PEKES and Nafion 117 membrane.     

Crosslinked Sulfonated Polysulfone-Based Polymer Electrolyte Membranes Induced by Gamma Ray Irradiation

Sulfonated aromatic polymers generally show high swelling at high proton conductivity. This disadvantage makes many of them unfit for proton exchange membrane applications. Crosslinking of the polymer is one way to overcome this problem. In this study, radiation-induced crosslinking was performed on a sulfonated polysulfone membrane, with doses ranging from 2.5 to 25.0 kGy (dose rate: 45 Gy/min) using gamma rays from a ⁶⁰Co source. The pristine sulfonated polysulfones was obtained by mild sulfonation of bisphenol-A-polysulfone with trimethylsilyl chlorosulfonate as sulfonating agent. The proton conductivity of the membranes was characterized by means of electrical impedance spectroscopy techniques. Ion-exchange capacity, degree of sulfonation, water content and chemical stability membrane properties were characterized before and after irradiation. The results show that the mechanical, chemical and thermal stability of the membrane improve after irradiation. The degree of sulfonation and the proton conductivity exhibit a tendency to decrease with increasing irradiation total dose.     

Physical and electrochemical behaviors of directly polymerized sulfonated poly(arylene ether ketone sulfone)s proton exchange membranes with different backbone structures

Sulfonated poly(ether ether ketone sulfone) (SPEEKS) and sulfonated poly(ether ether ketone ketone sulfone) (SPEEKKS) copolymers with different degree of sulfonation (DS) were synthesized by aromatic nucleophilic polycondensation of disodium 3,3′‐disulfonate‐4,4′‐dichloro‐diphenylsulfone (SDCDPS), tertbutylhydroquione, and 4,4′‐difluorobenzophenone or 1,4′‐bi(4‐fluorobenzoyl) benzene. Prepared sulfonated copolymers were characterized by Fourier transform infrared spectra, thermogravimetric analysis, and differential scanning calorimetry. The transmission electron microscope was used to investigate the microstructure of membranes. The different distance between two adjacent sulfonic groups in two series of membranes resulted in different physical and electrochemical properties between two kinds of membranes with the same DS. The proton conductivity, ionic exchange capacity and water uptake of SPEEKS membranes were higher than those of SPEEKKS membranes while the mechanical strength of SPEEKS membranes was lower than that of SPEEKKS membranes at the same DS. Moreover, the SPEEKKS membranes with DS equals to 0.8 showed a good combination of a high proton conductivity (0.046 S/cm at 25°C, 0.061 S/cm at 80°C), acceptable water uptake (33–65 wt %), excellent mechanical strength (tensile strength reached 49.7 MPa), and good thermal properties (T_g above 250°C, T_d5% above 300°C). It suggested that this could be a promising membrane for proton exchange membrane fuel cell application. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Properties and performance of composite electrolyte membranes based on sulfonated poly(arylenethioethersulfone) and sulfonated polybenzimidazole

A novel composite membranes comprising a sulfonated polyarylenethioethersulfone homopolymer (SPTES-100) and a sulfonated poly(p-phenylene benzobisimidazole) (SPBI), was described in this article. The composite membrane was obtained via a solution cast process in a mixture solvent of N, N-Dimethylacetamide (DMAc) and methanol (MeOH). The proton conductivity of the composite membranes was found to increase with the SPTES-100 content increased. The higher proton conductivity was ∼110 mS/cm at 85 °C and 85% relative humidity for the SPTES/SPBI 70/30 (wt) composite membrane which was considerably less than that of the 300 mS/cm of the SPTES-100 membrane. The mechanical properties indicated that the swelling of the composite membranes was reduced, which is relative to the SPTES-100 polymers, due to the reduced water uptake of the composite membrane by introducing the SPBI into the SPTES polymer matrix. The morphology of the SPTES/SPBI composite membranes was examined by a combination of techniques such as scanning electron microscopy (SEM) and elemental mapping to confirm the dispersion of the SPBI and study the micro-structure of the composite. The membrane electrode assembly (MEA) performance of the composite membranes was preliminary studied for H₂/Air fuel cells applications.     

Influence of chemical compositions on the properties of random and multiblock sulfonated poly(arylene ether sulfone)‐based proton‐exchange membranes

The influence of chemical compositions on the properties of sulfonated poly(arylene ether sulfone)‐based proton‐exchange membranes was studied. First, we synthesized three different series of random SPAES copolymers using three kinds of hydrophobic monomers, including 4,4′‐dihydroxyldiphenylether, 2,6‐dihydroxynaphthalene (DHN), and 4,4′‐hexafluoroisopropylidenediphenol (6F‐BPA) to investigate effects of hydrophobic components on the properties of SPAES membranes as proton‐exchange membranes. Random SPAES copolymers with 6F‐BPA showed the highest proton conductivity while random SPAES copolymers with DHN displayed the lowest methanol permeability among the three random copolymers. Subsequently, we synthesized multiblock SPAES using the DHN as a hydrophobic monomer and studied the effect of the length of hydrophilic segments in the multiblock SPAES copolymers on membrane performance. The results indicated that longer hydrophilic segments in the copolymers led to higher water uptake, proton conductivity, and proton/methanol selectivity of membranes even at low humidity. In addition, the morphology studies (AFM and SAXS measurements) of membranes suggested that multiblock copolymers with long hydrophilic segments resulted in developed phase separation in membranes, and ionic clusters formed more easily, thus improving the membrane performance. Therefore, both the kinds of hydrophobic monomers and the length of hydrophilic segments in SPAES copolymers would influence the membranes performance as proton‐exchange membranes. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Structures and properties of highly sulfonated poly(arylenethioethersulfone)s as proton exchange membranes

A series of sulfonated poly(sulfonium cation) polymers, sulfonated poly(arylenethioethersulfone)s (SPTES)s possess up to two sulfonate groups per repeat unit, and can be easily converted into corresponding acid form of the SPTES polymer to form a tough, ductile, free-standing, pinhole-free membranes with excellent mechanical properties. The SPTES polymers exhibit good water affinity and excellent proton conductivity due to the high water uptake. Proton conductivities between 100 and 300 mS/cm (at 65 °C, 85% relative humidity) were observed for the SPTES polymers with 50 mol% (SPTES-50) to 100 mol% (SPTES-100) of sulfonated monomer. The evaluation by thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), and thermomechanical analysis (TMA) showed that the SPTES polymers have excellent thermal stability, mechanical properties, and dimensional stability, making them excellent candidates for the next generation of proton exchange membranes (PEMs) in fuel cell applications.     

Preparation and properties of bisphenol A‐based sulfonated poly(arylene ether sulfone) proton exchange membranes for direct methanol fuel cell

Novel bisphenol A‐based sulfonated poly(arylene ether sulfone) (bi A‐SPAES) copolymers were successfully synthesized via direct copolymerization of disodium 3,3′‐disulfonate‐4,4′‐dichlorodiphenylsulfone, 4,4′‐dichlorodiphenylsulfone, and bisphenol A. The copolymer structure was confirmed by Fourier transform infrared spectra and ¹H NMR analysis. The series of sulfonated copolymers based membranes were prepared and evaluated for proton exchange membranes (PEM). The membranes showed good thermal stability and mechanical property. Transmission electron microscopy was used to obtain the microstructures of the synthesized polymers. The membranes exhibit increased water uptake from 8% to 66%, ion exchange capacities from 0.41 to 2.18 meq/g and proton conductivities (25°C) from 0.012 to 0.102 S/cm with the degree of sulfonation increasing. The proton conductivities of bi A‐SPAES‐6 membrane (0.10–0.15 S/cm) with high‐sulfonated degree are higher than that of Nafion 117 membrane (0.095–0.117 S/cm) at all temperatures (20–100°C). Especially, the methanol diffusion coefficients of membranes (1.7 × 10^?8 cm²/s–8.5 × 10^?7 cm²/s) are much lower than that of Nafion 117 membrane (2.1 × 10^?6 cm²/s). The new synthesized copolymer was therefore proposed as a candidate of material for PEM in direct methanol fuel cell. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009