Dielectric Spectroscopy of Polystyrene/Poly(ethylene oxide) Composites
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- 作者：Thomas W. Smith ; Martin A. Abkowitz ; Greg C. Conway ; David J. Luca ; Joseph M. Serpico ; and Gary E. Wnek
- 刊名：Macromolecules
- 出版年：1996
- 出版时间：July 1, 1996
- 年：1996
- 卷：29
- 期：14
- 页码：5042 - 5045
- 全文大小：183K
- 年卷期：v.29,no.14(July 1, 1996)
- ISSN：1520-5835
文摘
Dielectric spectra of composites of poly(ethylene oxide),PEO, in polystyrene, PS, have beenobtained, as a function of frequency and temperature. Thedispersion of a high-dielectric constant, low-glass transition temperature, semicrystalline polymer (PEO) in anamorphous, lower dielectric constant,high-Tg continuum (PS) has enabled thedielectric observation of four molecular relaxation processesinPEO. They are the 
relaxation associated with the crystallinemelt of PEO; two WLF type relaxations,
and ', which we speculate to be respectively associated with theonset of segmental motion and free-volume expansion of unrestricted amorphous PEO chains and with amorphousPEO chain segmentstethered in crystallites; and a sub-Tg, 
relaxation associated with localized motions in thecrystallinechain segments. The relaxations associated with the and 'processes have not been previously observeddielectrically. In pure, neat PEO, the and ' relaxationsare obscured by dc losses. The dispersion ofPEO as micron-sized and submicron phases in PS enables its fullrelaxation spectrum to be observed.
relaxation associated with the crystallinemelt of PEO; two WLF type relaxations, and ', which we speculate to be respectively associated with theonset of segmental motion and free-volume expansion of unrestricted amorphous PEO chains and with amorphousPEO chain segmentstethered in crystallites; and a sub-Tg, relaxation associated with localized motions in thecrystallinechain segments. The relaxations associated with the and 'processes have not been previously observeddielectrically. In pure, neat PEO, the and ' relaxationsare obscured by dc losses. The dispersion ofPEO as micron-sized and submicron phases in PS enables its fullrelaxation spectrum to be observed.