Dielectric relaxation spectroscopy in crosslinked polyurethanes based on polymer polyols

Kanapitsas, A; Pissis, P

dc.contributor.author	Kanapitsas, A	en
dc.contributor.author	Pissis, P	en
dc.date.accessioned	2014-03-01T01:15:33Z
dc.date.available	2014-03-01T01:15:33Z
dc.date.issued	2000	en
dc.identifier.issn	0014-3057	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/13580
dc.subject	Dielectric Relaxation	en
dc.subject	Differential Scanning Calorimetry	en
dc.subject	Glass Transition	en
dc.subject	Glass Transition Temperature	en
dc.subject	Sampling Technique	en
dc.subject.classification	Polymer Science	en
dc.subject.other	CHAIN-END GROUPS	en
dc.subject.other	SEGMENTED POLYURETHANES	en
dc.subject.other	BLOCK COPOLYMERS	en
dc.subject.other	MICROPHASE SEPARATION	en
dc.subject.other	GLASS-TRANSITION	en
dc.subject.other	ELASTOMERS	en
dc.subject.other	MORPHOLOGY	en
dc.subject.other	EXTENDERS	en
dc.subject.other	DSC	en
dc.title	Dielectric relaxation spectroscopy in crosslinked polyurethanes based on polymer polyols	en
heal.type	journalArticle	en
heal.identifier.primary	10.1016/S0014-3057(99)00167-6	en
heal.identifier.secondary	http://dx.doi.org/10.1016/S0014-3057(99)00167-6	en
heal.language	English	en
heal.publicationDate	2000	en
heal.abstract	This work deals with molecular mobility and microphase separation studies in blends of crosslinked polyurethanes and styrene-acrylonitrile (SAN), prepared by reactive blending, by means of differential scanning calorimetry (DSC) and dielectric relaxation spectroscopy (DRS) techniques. The DRS techniques employed include broadband ac techniques, 10(-2)-10(6) Hz, and thermally stimulated depolarization currents (TSDC) techniques, -180 to 30 degrees C. The results suggest, in agreement with each other by the different techniques, that SAN promotes the microphase separation between hard segment (HS) microdomains and soft segment (SS) microphase due to SAN-MS interactions, whereas SAN-SS interactions are weak. TSDC thermal sampling techniques show that a compensation law holds for the alpha relaxation associated with the glass transition of the SS microphase, with the compensation temperature being very close to the glass transition temperature. Analysis of the alpha relaxation in terms of fragility indicates that the systems under investigation are fragile. (C) 2000 Elsevier Science Ltd. All rights reserved.	en
heal.publisher	PERGAMON-ELSEVIER SCIENCE LTD	en
heal.journalName	EUROPEAN POLYMER JOURNAL	en
dc.identifier.doi	10.1016/S0014-3057(99)00167-6	en
dc.identifier.isi	ISI:000085986000018	en
dc.identifier.volume	36	en
dc.identifier.issue	6	en
dc.identifier.spage	1241	en
dc.identifier.epage	1250	en