Molecular Weight Dependence of Dielectric Behavior of Polymer Electrolytes under Shear Flow

Autor:	Yasuyuki Kimura, Shun Ichi Inoue, Reinosuke Hayakawa, Kohzo Ito
Rok vydání:	1999
Předmět:	chemistry.chemical_classification Permittivity Polypropylene Materials science Relaxation (NMR) General Engineering General Physics and Astronomy Thermodynamics Polymer Dielectric Conductivity Shear rate chemistry.chemical_compound chemistry Polymer chemistry Shear flow
Zdroj:	Japanese Journal of Applied Physics. 38:L665
ISSN:	1347-4065 0021-4922
DOI:	10.1143/jjap.38.l665
Popis:	We have developed a new apparatus for measuring dielectric relaxation under shear flow, and applied it to a typical polymer electrolyte system, polypropylene oxide (PPO)-lithium perchloride, while changing the molecular weight of PPO. We observed a drastic increase in dielectric increment Δε and a drastic decrease in conductivity σ with increasing shear rate. The molecular weight dependence of σ and the relaxation time τ suggests that the conductivity is due to ion transport assisted by the conformational change of the entire polymer chain and the permittivity is ascribed to the ion fluctuation within a single chain assisted by the segmental motion of a polymer. On applying shear flow, the conformational change of a polymer chain is strongly suppressed, which would cause the decrease in conductivity.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::f87a6bc44a304ac2b8be71896fc94749 https://doi.org/10.1143/jjap.38.l665 Zobrazit plný text záznamu