含N杂环磺化聚芳醚酮砜中高温质子交换膜传输通道的构筑、调控及构效关系

Proton exchange membrane fuel cell (PEMFC) has been paid extensive attention due to its numerous advantages, such as the sensitivity of the catalyst to CO can be reduced and platinum catalyst poisoning can be prevented when PEMFC operated on medium-high Proton exchange membrane fuel cell (PEMFC) has been paid extensive attention due to its numerous advantages, such as the sensitivity of the catalyst to CO can be reduced and platinum catalyst poisoning can be prevented when PEMFC operated on medium-high temperature (80-150 oC). However, as core component of PEMFC, commercialized Nafion® and sulfonated poly(arylene ether)s proton exchange membrane (PEM) has a lot of disadvantages. In medium-high temperature, the proton conductivity is low and dimensional stability is poor, which can not meet the requirements. Sulfonated poly(arylene ether ketone sulfone)s containing pendant amino groups were constructed by polycondensation reaction and introduced different nitrogen heterocycle into copolymers in this project. Nitrogen heterocycle act as both proton donor and acceptor, which are benefit to form ion transport channel and improve the proton conductivity at medium-high temperature. Silane coupling agent with nitrogen heterocycle and amino group was selected as macromolecular crosslinker and crosslinked with sulfonated poly(arylene ether ketone sulfone)s containing pendant amino groups to improve the dimensional stability. The low proton conductivity and poor dimensional stability at medium-high temperature will be resolved by the synergistic effect of Nitrogen heterocycle, crosslinking and silicon dioxide nanoparticle. Furthermore, the project will investigate the preparation methods of sulfonated poly(arylene ether ketone sulfone)s with different nitrogen heterocycle and clarify the transmission mechanism and effectiveness of different nitrogen heterocycle, establish the relationship between structure and properties and provide theoretical basis and scientific basis for sulfonated poly(arylene ether)s with nitrogen heterocycle as medium-high temperature PEM materials.

质子交换膜燃料电池在中高温（80-150℃）操作时能够降低催化剂对CO的敏感度、防止铂电催化剂中毒等优势而倍受青睐，但作为其核心组件商业用的Nafion®膜和被广泛研究的磺化聚芳醚类质子交换膜，在中高温下质子传导率较低、尺寸稳定性差，不能满足其使用要求。本申请课题拟从分子设计角度出发，通过缩聚和酰胺化反应将N杂环引入到磺化聚芳醚酮砜中。利用N杂环可充当质子受体与给体的双重特性，构建新的质子传输通道，提高PEM在中高温下的质子传导率。以带有氨基的N杂环硅烷偶联剂作为大分子交联剂制备交联型磺化聚芳醚酮砜，提高膜的尺寸稳定性。发挥N杂环、交联、二氧化硅纳米粒子的协同作用解决PEM在中高温下质子传导率低、尺寸稳定性差的问题。研究含N杂环磺化聚芳醚酮砜及交联膜的制备方法，阐明N杂环的传输机理和效能，建立结构与性能的关系，为含N杂环磺化聚芳醚类聚合物作为中高温用质子交换膜材料提供理论基础和科学依据。

燃料电池具有能量转化效率高、启动速度快、体积小等突出优势被广泛应用于军事、交通等领域，该项目针对现有氢氧燃料电池商用质子交换膜Nafion膜在中高温(＞80℃)操作时，质子传导率严重降低、甲醇渗透系数明显升高的问题。课题组从分子设计角度出发，通过缩聚反应将不同N杂环（吡啶、咪唑、三唑）引入到含氨基磺化聚芳醚中。利用N杂环可充当离子的受体与给体的双重特性，构建了新的离子传输通道，提高了膜在中高温下的离子传导率。以带有氨基的N杂环硅烷偶联剂作为大分子交联剂，与含有氨基的磺化聚芳醚进行交联，来提高膜的尺寸稳定性。发挥N杂环、交联、二氧化硅纳米粒子的协同作用提供新的离子传输位点，降低离子传输活化能，促进离子以“Grotthuss”机理进行传递，在保持良好机械性能的前提下提高了质子交换膜在中高温下的离子传导率。研究了不同含N杂环交联型磺化聚芳醚的制备方法，探索了不同N杂环的传输机理和效能，建立了结构与性能的构效关系。. 含N杂环交联膜操作温度可突破Nafion膜上限的80℃，在120℃时质子传导率可达0.83 Scm-1，并可在100-200℃之间稳定运行，在无外加湿条件180℃时，功率密度可达520mW cm-2，电流密度可达850 mAcm-2。研发的含N杂环聚芳醚酮质子交换膜在氢氧燃料电池中实现了工程应用，取得了一定的经济效益和社会效益。. 研究期间发表带有该基金号标注的SCI论文46篇，授权发明专利8项，作为第一完成人和完成单位申报的“高离子选择性电解质膜材料制备的关键技术及应用”获得吉林省科学技术二等奖（科技进步类）二等奖，“高性能电解质膜材料的关键制备技术及其应用”获得中国石油和化学工业联合会科学技术三等奖。组织了“长白山”青年学者离子膜论坛，带领课题组成员参加高分子年会、电驱动膜学术研讨会、第十届全国膜与膜过程学术报告会、全国储能大会等学术会议10余场，并做主题报告、邀请报告、口头报告、墙报等学术交流20余次。培养博士研究生3名，硕士研究生15名。