In this study, the chemical stability of three types of the anion-exchange functional groups in an alkaline environment was tested. The following groups were selected for the test: trimethylbenzylammonium, methyl pyridinium, and tributhylbenzylphosphonium. A KOH solution with various concentrations and temperatures was used as the environment. The trimethylbenzylammonium group showed the highest stability of the materials tested under conditions relevant to water electrolysis. In the next step, four types of polymeric binders, including ethyleneco-methacrylic acid, linear polyethylene, linear polyethylene blended with poly(ethylene-co-vinylalcohol), and low-density polyethylene, were selected to determine their impact on the resulting electrochemical properties of a heterogeneous membrane. This study reveals the morphology of the membrane, ion-exchange capacity, ionic conductivity, and performance in alkaline water electrolysis conducted on a laboratory scale. The material showing the most promising properties was selected for further optimization and testing.