NOVEL NAFION ORMOSIL HYBRIDS VIA IN-SITU SOL-GEL REACTIONS .1. PROBE OF ORMOSIL PHASE NANOSTRUCTURES BY INFRARED-SPECTROSCOPY

Novel [polymer]/[organically modified silicon oxide (ORIMOSIL)] hybrid s were formulated via sol-gel reactions of mixtures of tetraethoxysila ne (TEOS) and diethoxydimethylsilane (DEDMS) in the nanophase-separate d morphology of perfluorosulfonic acid (PFSA) films. Molecular structu res of ORMOSIL phases were investigated by FT-IR spectroscopy and the spectra compared with those of corresponding bulk ORMOSILs. Spectra ar e similar for PFSA in situ and bulk ORMOSILs, suggesting that short-ra nge molecular structures in the two states are in fact comparable. Spe ctral trends with ORMOSIL composition suggest that similar D, Q sequen ce distributions exist for the two systems. There is evidence of co-co ndensation between Q and D units within the PFSA, as well as in the bu lk ORMOSILs. As DEDMS:TEOS increases, ORMOSIL structures in both in si tu and bulk states are increasingly more linear. It appears that a spe ctrum of energetic environment, or polarity, in the clusters of perflu orosulfonate ionomers can be tailored by adjusting the ratio of Si-OH and Si-CH3 groups in ORMOSIL nanophases.