An in-situ Organic-Inorganic Hybrid Methanol-Permeation resistant PEM with Great Mechanical Stability Retention Capacity

An in-situ organic-inorganic hybrid strategy is proposed for proton exchange membrane (PEM) preparation based on a hyperbranched polyamide proton conductive macromolecule. With similar effects on proton conductivity and methanol permeability as that of the conventional organic-inorganic hybrid strategy, the in-situ organic-inorganic hybrid one showed much better retention capacity on mechanical stability. With trace amount of TiO2 nanoparticle, acting as a model inorganic filler in this work, methanol permeability of a previously developed macromolecular polyamide proton conductor, which already showed higher proton conductivity and methanol resistivity than the commercial Nafion membrane, is further reduced by ca. 20% while the proton conductivity is only slightly decayed. More importantly, mechanical strength of the in-situ hybrid membrane remained almost the same as that of the original polymeric membrane while the conventional hybrid strategy would lead to a 25% tensile strength loss.