Dielectric and NMR studies of the structure and dynamics ofsemicrystalline poly(ethylene oxide)

摘要

Both dielectric and NMR (nuclear magnetic resonance) spectroscopyare used to probe the molecular dynamics of poly(ethylene oxide). Anattempt is made to extend the understanding of molecular dynamics byusing two-dimensional NMR spectroscopy and dielectric spectroscopy oncarefully purified samples. NMR shows multiexponential behavior for thesingularities that represent immobile material. This complex relaxationbehavior demonstrates that there are two classes of immobile material, acrystalline phase and a rigid amorphous phase comprising 20% of thesample. Quenching experiments show that rapid cooling increases thefraction of mobile amorphous phase while the rigid amorphous phasefraction stays constant