【作者】 张宏伟；

【导师】 徐又一； 朱宝库；

【作者基本信息】 浙江大学 ， 高分子化学与物理， 2006， 博士

【摘要】 含二氮杂萘酮结构的聚醚酮（PPEK）是一种全新的高性能聚合物，具有优良的机械性能、热稳定性、化学稳定性和抗氧化性能。本论文目的是通过对PPEK磺化、氯甲基化/季铵化，以及将磺化PPEK与无机粒子如磷钨酸（PWA）、磷酸氢锆（ZrP）和硫酸氢铯（CS）掺杂等方法对PPEK进行改性。研究了燃料电池用聚电解质膜制备及其结构与性能的关系。首先，将PPEK在80～100℃的浓硫酸或氯磺酸和浓硫酸混合液中磺化，制备了磺化PPEK（SPPEK）膜，红外光谱、核磁共振谱和X-射线能量色散谱分析表明磺酸基团被成功引入PPEK分子主链。优化的PPEK磺化反应条件是：5g PPEK溶解于70ml浓硫酸和10ml氯磺酸溶液中，在90℃下反应3h。由SPPEK制备的SPPEK膜具有良好的阻甲醇渗透性，渗透系数为1.07×10^-7cm²/s，比Nafion117膜的甲醇渗透率(2.38×10^-6cm²/s)低20倍以上；SPPEK膜质子传导率在95℃时最大，为3.12×10^-2S/cm，基本满足聚电解质膜燃料电池的应用要求。其次，SPPEK与PWA掺杂所制备的PWA/SPPEK杂化膜热性能和机械性能未因磷钨酸粒子的引入而明显劣化，PWA含量为10wt％的PWA/SPPEK杂化膜（MP10）具有良好的阻甲醇渗透性，渗透系数为1.02×10^-7cm²/s，比Nafion117膜的甲醇渗透率低20倍以上，MP10质子传导率在80℃时具有最大值0.17S/cm，高于Nafion117膜的0.11S/cm。溶胀-浸渍法制备的α-ZrP/SPPEK杂化膜（Mz5）和直接混合法制备的α-ZrP/SPPEK杂化膜（Mz10）的甲醇渗透系数分为1.52×10^-7cm²/s和1.74×10^-7cm²/s，杂化膜Mz5的质子传导率比Mz10高一倍以上，Mz5和Mz10膜的质子传导率在95℃时最高，分别为7.65×10^-2S/cm和3.26×10^-2S/cm。同时研究还发现，硫酸氢铯的引入对SPPEK杂化膜性能有负面影响，硫酸氢铯含量为10％的CS/SPPEK杂化膜甲醇渗透系数力1.40×10^-7cm²/s，质子传导率最大为2.25×10^-2S/cm，这两种性能都比SPPEK相应的性能差。最后，由氯甲基化/季铵化改性的PPEK得到的碱性QPPEK膜甲醇渗透系数为7.21×10^-7cm²/s，比Nafion117膜的甲醇渗透系数低3倍，阴离子传导率最大为1.14×10^-2S/cm，基本满足低温碱性聚电解质膜燃料电池的工作需要。更多还原

【Abstract】 Poly（phthalazinone ether ketone） （PPEK） is a new kind of high performance polymer and has excellent mechanical properties, thermal stability, chemical and oxidative resistance. The aim of this work is to modify PPEK by means of sulfonation, chloromethylation/quaternization, doping sulfonated PPEK with inorganic particles such as cesium hydrogen sulfate （CS）, zirconium hydrogen phosphate hydrate （ZrP） and 12-phosphotungstic acid （PWA）, to prepare polymer electrolyte membranes （PEM） for fuel cells, and to study the relationship between structure and properties of the polymer electrolyte membranes.Firstly, the sulfonated PPEKs （SPPEKs） were synthesized by reacting PPEK with 98% concentrated sulfuric acid or 98% concentrated sulfuric acid and chlorosulfonic acid mixture under 80～100℃. The presence of sulfonic acid groups in SPPEKs was confirmed by Fourier transform infrared analysis, Energy Dispersive X-Ray and ¹H NMR spectrum. The optimum reaction conditions was 5g PPEK in the mixture of 70ml concentrated sulfuric acid of 98% and 10ml chlorosulfonic acid at 90℃ for 3h. The methanol permeability of SPPEK membrane was 1.07×10^-7 cm²/s, which was about 20 times lower than that of Nafion 117 (2.38×10^-6 cm² s（-1）) under similar condition. The SPPEK membrane showed the highest proton conductivity of 3.12×10^-2 S/cm at 95℃, which was in the range needed for the high performance fuel cell PEM.Secondly, the incorporation of the PWA into the SPPEK membrane did not damage the thermal stability and mechanical properties of the PWA/SPPEK hybrid membranes badly. The methanol permeability of the hybrid membrane containing 10 wt% PWA （MP10） was 1.02×10^-7 cm²/s, which was about 20 times lower than that of Nafion 117 under similar condition. MP10 showed the highest proton conductivity of 0.17 S/cm at 80℃, which was higher than that of Nafion 117 （0.11 S/cm）. The methanol permeabilities of a-ZrP/SPPEK hybrid membrane prepared from swell-dipping method （Mz5） and direct blending method （Mz10） were 1.52×10^-7 and 1.74×10^-7 cm² s^-1 respectively. The highest proton conductivities of Mz5 and Mz10 were 7.65 ×10^-2 S/cm and 3.26×10^-2 S/cm at 95℃. Doping CS into SPPEK membrane had a negative impact on the properties of CS/SPPEK hybrid membranes. The methanol permeability and thehighest proton conductivity of the hybrid membrane containing 10% CS were 1.40× 10^-7 cm²/s and 2.25×10^-2 S/cm respectively, which were lower than that of membrane SPPEK.Lastly, the quaternized PPEKs （QPPEKs） were modified by chloromethylation/ quaternization, and the alkaline QPPEK membrane had a methanol permeability 7.21× 10^-7 cm²/s and the highest anion conductivity 1.14×10^-2S/cm. It might be suitable for low temperature alkaline polymer electrolyte membrane fuel cells.更多还原