The direct sulfonation is a cheap process but introduces the valuable sulfonic acid groups onto the backbone of aromatic polymers for proton exchange membrane fuel cell applications. However, the chain-scission during sulfonation degrades the polymer backbone by cleavage of the linkages between the arylene rings. If the sulfonation is conducted at a relatively high temperature for long time, the degradation may be significant. In this paper, the chain-scission mechanisms of the typical aromatic polymers are studied in terms of transition states and activation energies using density functional theory calculations, and the improvement of the overall performances of sulfonated proton conducting materials is discussed.

直接磺化是一种廉价的方法，但是将有价值的磺酸基引入到质子交换膜燃料电池应用的芳族聚合物的骨架上。然而，在磺化过程中的断链通过裂解亚芳基环之间的键而使聚合物主链降解。如果磺化在相对较高的温度下长时间进行，则降解可能会很明显。本文利用密度泛函理论计算研究了过渡型态和活化能的典型芳族聚合物的断链机理，并探讨了磺化质子导电材料整体性能的提高。