Exploring the chemistry of electron-accepting molecules in the cavities of the basic microporous P4VP polymer by in situ FTIR spectroscopy

A systematic in situ FTIR investigation of the interaction of several molecules characterized by a different electron accepting ability (or acidity) with the basic pyridine units contained in a commercial poly(4-vinylpyridine) system characterized by a high surface area is here reported, with the final goal to fully understand the role of basicity in the catalytic processes. This approach, for the first time applied to polymeric materials, has only some similarities with the method usually adopted in the investigation of catalytic acid sites hosted inside oxidic porous materials (such as zeolites), where the probes are molecules characterized by an increased basicity. The experimental results are confirmed by ab initio theoretical calculations conducted on the 4-methylpyridine, which is the simplest molecule resembling the pyridine moiety in the P4VP system.