Molecular dynamics in PVDF/PVA blends as revealed by dielectric loss spectroscopy |
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| Authors: | A Linares A Nogales D R Rueda T A Ezquerra |
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| Institution: | 1. Instituto de Estructura de la Materia, CSIC, Serrano 119, Madrid 28006, SpainInstituto de Estructura de la Materia, CSIC, Serrano 119, Madrid 28006, Spain;2. Instituto de Estructura de la Materia, CSIC, Serrano 119, Madrid 28006, Spain |
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| Abstract: | The relaxation behavior of a series of compatible poly(vinylidene fluoride) (PVDF) and poly(vinyl acetate) (PVA) blends has been investigated by dielectric spectroscopy in a broad frequency and temperature range. Blends with PVDF content higher than 60% in weight are semicrystalline. Semicrystalline blends show a relaxation (αc) occurring in the crystalline phase of PVDF. Both semicrystalline and amorphous blends exhibit two processes, α and β associated to the overall segmental dynamics and to localized motions in the amorphous phase, respectively. For high PVDF content samples, the β relaxation exhibits an anomalous behavior characterized by a crossover from segmental to local dynamics, upon decreasing temperature, attributed to confinement effects taking place in PVDF segregated regions. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 1653–1661, 2007 |
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| Keywords: | blends dielectric properties nanoheterogeneity PVDF PVA |
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