Wu Gwomei, Lin Sheng-Jen, Hsu I-Chan, Su Juin-Yih, Chen Dave W
Institute of Electro-Optical Engineering, Department of Chemical and Materials Engineering, Chang Gung University, Taoyuan 333, Taiwan.
Chang Gung Memorial Hospital, Keelung 204, Taiwan.
Polymers (Basel). 2019 Jul 12;11(7):1177. doi: 10.3390/polym11071177.
In this study, high performance composite electrolyte membranes were prepared from polyether ether ketone polymeric material. An initial sulfonation reaction improved the membrane hydrophilicity and its water absorbability and thus enhanced the ionic conductivity in electrochemical cells. Protonic conductivity was improved from 10 to 10 S cm with an increasing sulfonation time from 72 to 175 h. The effects of blending nano SiO into the composite membranes were devoted to improve thermal and mechanical properties, as well as methanol permeability. Methanol permeability was reduced to 3.1 × 10 cm s. Finally, a further improvement in ionic conductivity was carried out by a supercritical carbon dioxide treatment under 20 MPa at 40°C for 30 min with an optimum SiO blend ratio of 10 wt-%. The plasticizing effect by the Lewis acid-base interaction between CO and electron donor species on polymer chains decreased the glass transition and melting temperatures. The results show that sulfonated composite membranes blended with SiO and using a supercritical carbon dioxide treatment exhibit a lower glass transition temperature, higher ionic conductivity, lower methanol permeability, good thermal stability, and strong mechanical properties. Ionic conductivity was improved to 1.55 × 10 S cm. The ion exchange capacity and the degree of sulfonation were also investigated.
在本研究中，由聚醚醚酮聚合物材料制备了高性能复合电解质膜。初始磺化反应提高了膜的亲水性及其吸水性，从而提高了电化学电池中的离子电导率。随着磺化时间从72小时增加到175小时，质子电导率从10提升至10 S cm。将纳米SiO混入复合膜中的作用是改善热性能和机械性能以及甲醇渗透性。甲醇渗透率降低至3.1×10 cm s。最后，在20 MPa、40°C下进行30分钟的超临界二氧化碳处理，并采用10 wt-%的最佳SiO混合比例，进一步提高了离子电导率。CO与聚合物链上电子供体物种之间的路易斯酸碱相互作用产生的增塑效应降低了玻璃化转变温度和熔点。结果表明，与SiO混合并经过超临界二氧化碳处理的磺化复合膜具有较低的玻璃化转变温度、较高的离子电导率、较低的甲醇渗透率、良好的热稳定性和较强的机械性能。离子电导率提高到了1.55×10 S cm。还研究了离子交换容量和磺化度。
