The kinetic degradation models for MEA used in this work have been adapted from previously developed oxidative and thermal degradation models described in Braakhuis et al. & Braakhuis and Knuutila . The kinetic rate constants in both models are defined using the adjusted form of the Arrhenius equation shown in Eq. 3. The equations use a reference temperature and reaction rate coefficient at this temperature, simplifying the parameter fitting and optimisation.