Influence of chain extenders and chain end groups on properties of segmented polyurethanes. II. Dielectric study

Pissis, P; Kanapitsas, A; Savelyev, YuV; Akhranovich, ER; Privalko, EG; Privalko, VP

dc.contributor.author	Pissis, P	en
dc.contributor.author	Kanapitsas, A	en
dc.contributor.author	Savelyev, YuV	en
dc.contributor.author	Akhranovich, ER	en
dc.contributor.author	Privalko, EG	en
dc.contributor.author	Privalko, VP	en
dc.date.accessioned	2014-03-01T01:13:50Z
dc.date.available	2014-03-01T01:13:50Z
dc.date.issued	1998	en
dc.identifier.issn	0032-3861	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/12739
dc.subject	Degree of microphase separation	en
dc.subject	Primary and secondary transitions	en
dc.subject	Segmented polyurethanes	en
dc.subject.classification	Polymer Science	en
dc.subject.other	Composition effects	en
dc.subject.other	Dielectric relaxation	en
dc.subject.other	Electric conductivity of solids	en
dc.subject.other	Glycols	en
dc.subject.other	Molecular structure	en
dc.subject.other	Phase separation	en
dc.subject.other	Chain extenders	en
dc.subject.other	Diphenylmethane diisocyanate	en
dc.subject.other	Maxwell Wagner Sillars (MWS) polarization	en
dc.subject.other	Oligotetramethylene glycol	en
dc.subject.other	Thermally stimulated depolarization currents (TSDC) measurements	en
dc.subject.other	Polyurethanes	en
dc.title	Influence of chain extenders and chain end groups on properties of segmented polyurethanes. II. Dielectric study	en
heal.type	journalArticle	en
heal.identifier.primary	10.1016/S0032-3861(97)10100-8	en
heal.identifier.secondary	http://dx.doi.org/10.1016/S0032-3861(97)10100-8	en
heal.language	English	en
heal.publicationDate	1998	en
heal.abstract	Thermally stimulated depolarization currents (TSDC) measurements (temperature range 77-300K) and broadband a.c. dielectric relaxation spectroscopy (frequency range 10 mHz-2 GHz) were employed to investigate molecular mobility and microphase separation in model segmented polyurethanes (SPUs) from oligotetramethylene glycol 1000, 4,4'-diphenylmethane diisocyanate and different chain extenders. The magnitude of the interfacial Maxwell-Wagner-Sillars (MWS) polarization TSDC peak and of d.c. conductivity have proved to sensitively reflect changes of the degree of microphase separation (DMS). The dielectric strength of both the primary and the secondary transition of the soft segments rich microphase are highest for the SPU with the highest DMS, whereas frequency (temperature) position and shape of the response are not significantly affected by DMS. (C) 1998 Elsevier Science Ltd. All rights reserved.	en
heal.publisher	ELSEVIER SCI LTD	en
heal.journalName	Polymer	en
dc.identifier.doi	10.1016/S0032-3861(97)10100-8	en
dc.identifier.isi	ISI:000073791900019	en
dc.identifier.volume	39	en
dc.identifier.issue	15	en
dc.identifier.spage	3431	en
dc.identifier.epage	3435	en