Comb-shaped SEBS-based anion exchange membranes with obvious microphase separation morphology

•The comb-shaped structure was introduced into the SEBS-based AEMs.•The comb-shaped AEMs exhibit high ion transmission efficiency owe to the form of the interconnected channels.•The comb-shaped structure can effectively ameliorate the solubility to solve the gelation problem of SEBS. The trade-off between stability and hydroxide conductivity plays an important role in the development of anion exchange membranes (AEMs) and AEM applications. Aiming at the problems of low OH− ion conductivity and poor stability of AEMs, poly(styrene-b-(ethylene-co-butylene)-b-styrene) (SEBS) was used as the polymer backbone and combined with tertiary amines with different carbon chain lengths to synthesize a series of comb-shaped membranes through Menshutkin reaction. The well-designed architecture of comb-shaped membranes was responsible for precisely adjusting the hydrophilic and hydrophobic phases to promote the self-aggregation of ion clusters in the membrane from the separated state and gradually form interconnected ion channels. This continuous channel significantly increased the ion conductivity (57.5 mS cm−1 at 80 °C), while the increased hydrophobic chain reduced the swelling ratio (14.17% at 80 °C) of the comb-shaped membranes which improved the dimensional stability. In the single cell evaluation, the comb-shaped membrane achieves a maximum power density of 176 mW cm−2 at 80 °C under H2/O2 conditions. Additionally, the comb-shaped structure can effectively ameliorate the solubility of the polymer, which can solve the gelation problem in the process of functional modification of SEBS. On balance, this work presents a new technology with such uncomplicated and controllable mode for the synthesis of highly efficient AEMs, thus opening an effective and adjustable means of anion exchange membrane fuel cell applications. [Display omitted]