writer：Yongbing Zhuang，Jong Geun Seong，Yu Seong Do，Hye Jin Jo，Zhaoliang Cui，Jongmyeong Lee，Young Moo Lee*
keywords：Intrinsically microporous soluble polyimides
source：期刊
specific source：Macromolecules
Issue time：2014年

Two series of random sulfonated poly(benzothiazole-co-benzimidazole)

polymers (sPBT-BI) with 70% and 60% degree of sulfonation were

evaluated as proton exchange membranes. sPBT was also prepared for a

comparative study. The mechanical properties of sPBT-BI were greatly

enhanced by incorporation of benzimidazole (BI); sPBT-BI70-10 showed a

tensile strength of 125 MPa and elongation at break of 38.9%, an

increase of 56.5% and 145%, respectively, compared with sPBT. The

solubility, dimensional stability, thermal properties, and oxidative

stability of sPBT-BI were also improved. The ionic clusters of sPBT-BI

membranes in both AFM phase images and TEM images became narrower with

increasing amounts of BI while containing the same molar amount of

sulfonic acid groups. This resulted in lower dimensional swelling and

higher mechanical strength, but the proton conductivity decreased.

However, high proton conductivity was achieved by incorporating an

appropriate content of BI. PEMFC H2/air single cell performances and durabilities were improved by incorporation of 5% of BI units in sPBT