通过比较由乙烯基添加多化聚合物共聚合物衍生的和四氨基阳离子交换膜
Jamie C Gaitor1, Ami C Yang-Neyerlin2, Danielle Markovich3
1Department of Chemistry, Carnegie Mellon University, 4400 Fifth Ave, Pittsburgh, Pennsylvania 15213, United States.
概括
这项研究开发了新型的离子交换膜 (AEMs),使用维尼尔添加聚甲基. 基于的优化AEM在燃料电池中实现了高氧导电性和高性能.
科学领域:
- 聚合物化学 聚合物化学
- 材料科学 材料科学 材料科学
- 电化学 电化学 电化学
背景情况:
- 阳离子交换膜 (AEM) 对性燃料电池和其他电化学应用至关重要.
- 乙烯基加 polynorbornene 提供了一个多功能平台,用于设计具有可调节性质的 AEM.
- 控制聚合物组成和离子类型是优化AEM性能的关键.
研究的目的:
- 系统地研究组合对乙烯基添加聚乙烯 AEM 特性的影响.
- 用氨和四氨基酸来合成和表征AEM.
- 评估这些AEM在燃料电池应用中的性能.
主要方法:
- 5-n-hexyl-2-norbornene和5-(4-bromobutyl)-2-norbornene的联合聚合. 在这种情况下,
- 聚合后功能化引入和四氨基酸.
- 膜性质的表征,包括导电性,吸水和形态.
- 膜电极组件的燃料电池测试.
主要成果:
- 同聚合动力学有利于甲基组的结合,使得可控的功能化.
- 优化的氨AEM显示出高氧导电性 (在80°C时为95±6mS/cm).
- 氨基AEMs显示了这种阴离子类型报告的最高导电性 (在80°C时70±3毫秒/厘米).
- 氨AEM显示出优越的燃料电池性能 (峰值功率密度为1.59W/cm2).
结论:
- 聚合物成分对AEM的性能和性能产生重大影响.
- 基于的AEM为性燃料电池提供了有前途的性能,因为它具有有利的水透性和导电性.
- 四氨基AEMs虽然具有高导电性,但燃料电池性能较低,可能是由于形态差异.
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