车用燃料电池质子交换膜的制备及性能

合成了一系列具有不同支化度的磺化聚芳醚砜材料,并对其结构和性能进行了表征。所制备的磺化的支化聚芳醚砜材料的分子量可达7.00×105以上,并且分子量分布在1.17左右,拉伸强度可达20.55~28.81 MPa。随着聚合物支化度的增加,聚合物的热稳定性得到改善,在550℃下的热失重可降低至39%~45%。高支化的磺化聚芳醚砜薄膜的氧化稳定性也得到改善,80℃下的使用寿命可提高至7.25 h。支化的磺化聚芳醚砜薄膜的吸水率和质子传导率都较高。80℃下高支化度的聚芳醚砜薄膜的质子传导率可达0.33 S/cm。对其微观形貌进行观测发现,支化聚芳醚砜中的支化结构可对周围的亲水磺酸基团起支撑作用,促使其发生团聚而形成连续的质子通道。

Preparation and Performance of Proton Exchange Membrane for Automotive Fuel Cells

A series of sulfonated poly(aryl ether ketone) materials with different degree of branching were synthesized,and the structure and properties were characterized. The obtained polymers showhigh molecular weight as up to 7.00×105,narrow mo-lecular weight distribution as 1.17,and high tensile strength as 20.55–28.81 MPa. Following with the increase of polymer branching degree,the thermal stability and oxidation stability are improved. The weight loss at 550℃ is controlled at 39%–45%,the lifetime at 80℃is improved to 7.25 h. The branched sulfonated poly(aryl ether ketone) membrane materials show higher rate of water absorp-tion and proton conductivity. The polymer branched sulfonated poly(aryl ether ketone) membrane material with high branching dgree exhibites high proton conductivity as 0.33 S/cm at 80℃. Through the observation of the micro morphology,it is found that the branching structure of branched poly(aryl ether ketone) can support the surrounding hydrophilic sulfonic acid groups,and promote the formation of a continuous proton channel.