Structure-property relationships in brittle polymer networks modified by flexible cross-links

Kripotou, S; Pissis, P; Kontou, E; Fainleib, AM; Grygoryeva, O; Bey, I

dc.contributor.author	Kripotou, S	en
dc.contributor.author	Pissis, P	en
dc.contributor.author	Kontou, E	en
dc.contributor.author	Fainleib, AM	en
dc.contributor.author	Grygoryeva, O	en
dc.contributor.author	Bey, I	en
dc.date.accessioned	2014-03-01T01:25:12Z
dc.date.available	2014-03-01T01:25:12Z
dc.date.issued	2006	en
dc.identifier.issn	0137-1339	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/17596
dc.relation.uri	http://www.scopus.com/inward/record.url?eid=2-s2.0-33745784175&partnerID=40&md5=2058d6cd360b0fffccee60aa5e323c5d	en
dc.subject	Dielectric spectroscopy	en
dc.subject	Main α relaxation	en
dc.subject	Modified polycyanurate network	en
dc.subject	Polyoxytetramethylene glycol (PTMG)	en
dc.subject.classification	Materials Science, Multidisciplinary	en
dc.subject.other	Crosslinking	en
dc.subject.other	Crystalline materials	en
dc.subject.other	Dielectric properties	en
dc.subject.other	Glass transition	en
dc.subject.other	Morphology	en
dc.subject.other	Dielectric spectroscopy	en
dc.subject.other	Main α relaxation	en
dc.subject.other	Modified polycyanurate network	en
dc.subject.other	Polyoxytetramethylene glycol (PTMG)	en
dc.subject.other	Polymers	en
dc.title	Structure-property relationships in brittle polymer networks modified by flexible cross-links	en
heal.type	journalArticle	en
heal.language	English	en
heal.publicationDate	2006	en
heal.abstract	Hybrid polycyanurate/polyoxytetramethylene glycol (PCN/PTMG) networks were prepared from PCN and PTMG (molar mass 1.000 g/mol) with 10, 20, 30 and 40 wt. % PTMG. The degree of incorporation of PTMG into the PCN network was determined by gel fraction measurements. Earlier morphological and thermal transition studies indicated a non-crystalline structure, considerable nanostructural heterogeneity and a wide dispersion of glass transition temperatures of the hybrid networks. The present paper reports on a continued investigation of structure-property relationships and employ dielectric techniques to focus on molecular dynamics. Two secondary relaxations of PCN, one secondary relaxation of PTMG and a single, broad a relaxation (dynamic glass transition) were detected in the hybrids. The a relaxation was studied in detail over wide ranges of temperature and frequency. The results were system-atically analyzed in terms of time scale, relaxation strength and shape of the response, and are discussed in terms of plasticization, presence of nanostructural heterogeneities (composition fluctuations) and hybridization. A distinctly different behaviour, observed for the hybrid with 30% PTMG, is explained in terms of a more pronounced nanoheterogeneous structure. Finally, stress-strain measurements were performed and their results are discussed in terms of structure and molecular dynamics.	en
heal.publisher	OFICYNA WYDAWNICZA POLITECHNIKI WROCLAWSKIEJ	en
heal.journalName	Materials Science- Poland	en
dc.identifier.isi	ISI:000238978200007	en
dc.identifier.volume	24	en
dc.identifier.issue	2 II	en
dc.identifier.spage	477	en
dc.identifier.epage	492	en