Anion exchange membranes (AEM) are key components in anion exchange membrane water electrolysers. Recently developed materials are less susceptible to the alkaline degradation of the polymer backbone and quaternary ammonium groups. A remaining challenge is the mechanical stability in contact with hot water and dimensional stability when the temperature of the feed solution changes. One solution is to reinforce membranes with a porous support. Since support materials like PEEK or PTFE have a different swelling behavior than the matrix and no strong interactions with the matrix, voids can form, and gas crossover increases. In this work, we approach this issue by pore filling polybenzimidazole nanofiber mats with the bromomethylated precursor of mTPN, an ultra-stable AEM material. During drying, a covalent interaction between support (PBI amine groups) and matrix (-CH₂Br) is established. After quaternization, the optimized PBI/mTPN-50.120 composite membrane still shows a high conductivity of 62 mS cm⁻¹, but 37% reduced length swelling in comparison to the non-reinforced membrane. Tensile strength and Young's modulus increase 17% and 56% to 49 MPa and 680 MPa, respectively. In an electrolyser, a stable voltage of 1.98V at 0.25 A cm⁻² was achieved, and no change in membrane resistance was observed over the test time of 200 h (50 °C, 1 M KOH, catalysts based on Ni/Fe and Mo).

阴离子交换膜 (AEM) 是阴离子交换膜水电解槽的关键部件。最近开发的材料对聚合物骨架和季铵基团的碱性降解不太敏感。剩下的挑战是与热水接触时的机械稳定性和进料溶液温度变化时的尺寸稳定性。一种解决方案是用多孔支撑物加强膜。由于诸如 PEEK 或 PTFE 之类的支撑材料具有与基体不同的溶胀行为，并且与基体没有强相互作用，因此会形成空隙并增加气体渗透。在这项工作中，我们通过用 mTPN（一种超稳定的 AEM 材料）的溴甲基化前体填充聚苯并咪唑纳米纤维垫来解决这个问题。在干燥过程中，₂ Br) 成立。季铵化后，优化的 PBI/mTPN-50.120 复合膜仍显示出 62 mS cm ^-1的高电导率，但与非增强膜相比，长度膨胀减少了 37%。拉伸强度和杨氏模量分别增加 17% 和 56% 至 49 MPa 和 680 MPa。在电解槽中，在 0.25 A cm ^-2下实现了 1.98V 的稳定电压，并且在200 小时（50 °C，1 M KOH，基于 Ni/Fe 和莫）。