Poly(ethyl methacrylate-co-hydroxyethyl acrylate) random co-polymers: Dielectric and dynamic-mechanical characterization

Gomez Tejedor, JA; Rodriguez Acosta, T; Gomez Ribelles, JL; Polizos, G; Pissis, P

dc.contributor.author	Gomez Tejedor, JA	en
dc.contributor.author	Rodriguez Acosta, T	en
dc.contributor.author	Gomez Ribelles, JL	en
dc.contributor.author	Polizos, G	en
dc.contributor.author	Pissis, P	en
dc.date.accessioned	2014-03-01T01:26:55Z
dc.date.available	2014-03-01T01:26:55Z
dc.date.issued	2007	en
dc.identifier.issn	0022-3093	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/18282
dc.subject	Dielectric properties	en
dc.subject	Electric modulus	en
dc.subject	Polymers and organics	en
dc.subject	Relaxation	en
dc.subject	Structural relaxation	en
dc.subject.classification	Materials Science, Ceramics	en
dc.subject.classification	Materials Science, Multidisciplinary	en
dc.subject.other	Conformations	en
dc.subject.other	Dielectric relaxation	en
dc.subject.other	Dynamic mechanical analysis	en
dc.subject.other	Elastic moduli	en
dc.subject.other	Polymethyl methacrylates	en
dc.subject.other	Spectroscopic analysis	en
dc.subject.other	Electric modulus	en
dc.subject.other	Havriliak-Negami equations	en
dc.subject.other	Structural relaxation	en
dc.subject.other	Copolymers	en
dc.title	Poly(ethyl methacrylate-co-hydroxyethyl acrylate) random co-polymers: Dielectric and dynamic-mechanical characterization	en
heal.type	journalArticle	en
heal.identifier.primary	10.1016/j.jnoncrysol.2006.11.003	en
heal.identifier.secondary	http://dx.doi.org/10.1016/j.jnoncrysol.2006.11.003	en
heal.language	English	en
heal.publicationDate	2007	en
heal.abstract	The conformational mobility in poly(ethyl methacrylate-co-hydrxyethyl acrylate) co-polymers was studied by dielectric relaxation spectroscopy, thermally stimulated depolarization currents and dynamic-mechanical experiments. The relaxation strength and the shape of the dielectric relaxation spectra of the homopolymer and co-polymer networks were analyzed using the Havriliak-Negami equation. The dependence of the relaxation strength on co-polymer composition and temperature was analyzed taking into account the merging of the main and the secondary relaxation processes. The shape of the epsilon" versus frequency plots led to the conclusion that the distribution of relaxation times was broader in the co-polymers with intermediate composition than in the homopolymers, a feature that can be explained by the inhomogeneity produced at molecular scale by the sequence distribution of the monomeric units along the chain. Master curves were built both for the elastic modulus and the mechanical loss tangent, and the temperature dependence of the relaxation times was deduced from the shift factors. The fit to the Vogel equation permitted the calculation of the strength parameter, which is higher in the co-polymers that the simple average of the values of the homopolymers, a feature that can be related to the broadness of the distribution of relaxation times. (c) 2006 Elsevier B.V. All rights reserved.	en
heal.publisher	ELSEVIER SCIENCE BV	en
heal.journalName	Journal of Non-Crystalline Solids	en
dc.identifier.doi	10.1016/j.jnoncrysol.2006.11.003	en
dc.identifier.isi	ISI:000244630300007	en
dc.identifier.volume	353	en
dc.identifier.issue	3	en
dc.identifier.spage	276	en
dc.identifier.epage	285	en