Sulfonated polyaryletherketone with pendant benzimidazole groups for proton exchange membranes
writer：Jun Liang, Jiao Ge, Kai Wu, Qi Zhang, Jianli Wang*, Zhibin Ye**
keywords：proton exchange membranes; amphoteric polymers; sulfonated polyaryletherketone
source：期刊
specific source：Journal of Membrane Science
Issue time：2019年
我們合成了一系列磺化聚芳醚酮(x%SCBI-SPAEK-6F)與苯并咪唑側基，其摩爾百分比可調(x在5 - 15%)，具有作為質子交換膜(PEM)的潛在應用價值。系統地研究了這些新型兩性聚合物的性能及其結構與性能之間的關系。結果表明，隨著苯并咪唑含量的增加，x%SCBI-SPAEK-6F膜的尺寸穩定性、氧化穩定性和耐甲醇性能顯著提高。特別是5%SCBI-SPAEK-6F膜在75℃時的相對選擇性(10.5×103 S S cm-3)幾乎是Nafion117膜的20倍，說明酸堿交聯作用顯著提高了質子電導率(0.35 S cm-1)，降低了甲醇滲透率(6×10-7 cm2 S -1)。這些聚合物具有優異的性能，有望用于商業燃料電池中質子交換膜的制備。
We synthesized a range of sulfonated polyaryletherketone (x%SCBI-SPAEK-6F) with pendant benzimidazole side groups at a tunable molar percentage (x within 5-15%) for potential application as proton exchange membrane (PEM). A systematic study had been undertaken to study the performance and the underlying structure-properties relationship of PEMs fabricated by those novel amphoteric polymers. It was found that the dimensional stability, oxidative stability and methanol resistance performance of x%SCBI-SPAEK-6F membranes were significantly improved with the increase of the benzimidazole content due to the acid-base interaction. In particular, the 5%SCBI-SPAEK-6F membrane exhibited a relative selectivity (10.5×103 S s cm-3) almost 20 times higher than that of Nafion117 membrane at 75℃, demonstrating the significant promoted proton conductivity (0.35 S cm-1) and reduced methanol penetration (6 ×10-7 cm2 s-1) by the ionic barrier. With such superior performance, these polymers are promising for the fabrication of practical proton exchange membranes in commercial fuel cells.
Scheme 1. Synthesis of x%SCBI-60SPAEK-6F polymers and chemical structure of x%MCBI-60SPAEK-6F.
DOI: https://doi.org/10.1016/j.memsci.2019.117626