As we all know, introducing crosslinking groups into the polymer chain can effectively improve the overall performance of proton exchange membranes, which are for the formation of intermolecular three-dimensional network. In this work, side-chain nitrile-based cross-linked sulfonated poly(arylene ether nitrile) (SPEN) membrane is expected to be an ideal material for preparing proton exchange membranes (PEMs). A series of SPEN-60-COOH-x with different carboxyl content have been synthesized through fixing the content of sulfonic group at 60% in the experiment and changing the molar fraction of phenolphthalein (PPL). Then, the SPEN-60-CN-x were prepared by grafting nitrile groups onto the SPEN-60-COOH-x via carboxyl groups. NMR and FTIR were used to characterize the construction of polymers. The TGA results showed that the thermal stability of CSPEN-60-CN-x was significantly improved by the cross-linking network structure formed by side chain nitrile groups. As the degree of cross-linking increases, the water uptake of CSPEN-60-CN-x membranes showed a downward trend. The results also indicated that the dimension stability of CSPEN-60-CN-x membranes was effectively improved by cross-linking reaction, and the dimension stability of CSPEN-60-CN-x membranes was further improved by increasing the content of nitrile groups. The selectivity of CSPEN-60-CN-x membranes increased significantly after crosslinking. CSPEN-60-CN-30 has the highest selectivity of 5.37 × 10⁵ S·s·cm⁻³ among all the membranes, about 11.9 times that of Nafion 117.

众所周知，在聚合物链中引入交联基团可以有效地改善质子交换膜的整体性能，该质子交换膜用于形成分子间三维网络。在这项工作中，基于侧链腈的交联磺化聚亚芳基醚腈（SPEN）膜有望成为制备质子交换膜（PEM）的理想材料。通过在实验中将磺酸基的含量固定在60％，并改变酚酞（PPL）的摩尔分数，合成了一系列具有不同羧基含量的SPEN-60-COOH-x。然后，通过经由羧基将腈基接枝到SPEN-60-COOH-x上来制备SPEN-60-CN-x。NMR和FTIR用于表征聚合物的结构。TGA结果表明，CSPEN-60-CN-x的热稳定性通过侧链腈基形成的交联网络结构得到了显着改善。随着交联度的增加，CSPEN-60-CN-x膜的吸水率呈下降趋势。结果还表明，通过交联反应可有效改善CSPEN-60-CN-x膜的尺寸稳定性，并通过增加腈基含量进一步改善CSPEN-60-CN-x膜的尺寸稳定性。交联后，CSPEN-60-CN-x膜的选择性显着提高。CSPEN-60-CN-30的最高选择性为5.37×10 CSPEN-60-CN-x膜的吸水率呈下降趋势。结果还表明，通过交联反应可有效改善CSPEN-60-CN-x膜的尺寸稳定性，并通过增加腈基含量进一步改善CSPEN-60-CN-x膜的尺寸稳定性。交联后，CSPEN-60-CN-x膜的选择性显着提高。CSPEN-60-CN-30的最高选择性为5.37×10 CSPEN-60-CN-x膜的吸水率呈下降趋势。结果还表明，通过交联反应可有效改善CSPEN-60-CN-x膜的尺寸稳定性，并通过增加腈基含量进一步改善CSPEN-60-CN-x膜的尺寸稳定性。交联后，CSPEN-60-CN-x膜的选择性显着提高。CSPEN-60-CN-30的最高选择性为5.37×10在所有膜中为⁵  S·s·cm ^-3，约为Nafion 117的11.9倍。