Molecular mobility and crystallinity in polytetramethylene ether glycol in the bulk and as soft component in polyurethanes

Raftopoulos, KN; Janowski, B; Apekis, L; Pielichowski, K; Pissis, P

dc.contributor.author	Raftopoulos, KN	en
dc.contributor.author	Janowski, B	en
dc.contributor.author	Apekis, L	en
dc.contributor.author	Pielichowski, K	en
dc.contributor.author	Pissis, P	en
dc.date.accessioned	2014-03-01T01:36:21Z
dc.date.available	2014-03-01T01:36:21Z
dc.date.issued	2011	en
dc.identifier.issn	0014-3057	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/21288
dc.subject	Contour plots	en
dc.subject	Glass transition	en
dc.subject	Microphase separation	en
dc.subject	Polyetramethylene ether glycol	en
dc.subject	Polyurethane	en
dc.subject	Segmental dynamics	en
dc.subject.classification	Polymer Science	en
dc.subject.other	Arrhenius	en
dc.subject.other	Butanediol	en
dc.subject.other	Chain extenders	en
dc.subject.other	Contour plot	en
dc.subject.other	Crystallinities	en
dc.subject.other	Crystallization process	en
dc.subject.other	Dielectric data	en
dc.subject.other	Dielectric relaxation spectroscopy	en
dc.subject.other	Dielectric response	en
dc.subject.other	Diisocyanates	en
dc.subject.other	Dynamic glass transition	en
dc.subject.other	H-bonding	en
dc.subject.other	Local dynamics	en
dc.subject.other	Macrodiols	en
dc.subject.other	Melting process	en
dc.subject.other	Micro-phase	en
dc.subject.other	Modulated differential scanning calorimetry	en
dc.subject.other	Molecular mobility	en
dc.subject.other	Polyetramethylene ether glycol	en
dc.subject.other	Segmental dynamics	en
dc.subject.other	Soft components	en
dc.subject.other	Soft segments	en
dc.subject.other	Thermally stimulated depolarization currents	en
dc.subject.other	Arrhenius plots	en
dc.subject.other	Crystallization	en
dc.subject.other	Differential scanning calorimetry	en
dc.subject.other	Ethers	en
dc.subject.other	Glass	en
dc.subject.other	Glass bonding	en
dc.subject.other	Glycols	en
dc.subject.other	Melting	en
dc.subject.other	Microphase separation	en
dc.subject.other	Molecular weight	en
dc.subject.other	Organic compounds	en
dc.subject.other	Polyurethanes	en
dc.subject.other	Spectroscopy	en
dc.subject.other	Spinodal decomposition	en
dc.subject.other	Glass transition	en
dc.title	Molecular mobility and crystallinity in polytetramethylene ether glycol in the bulk and as soft component in polyurethanes	en
heal.type	journalArticle	en
heal.identifier.primary	10.1016/j.eurpolymj.2011.07.020	en
heal.identifier.secondary	http://dx.doi.org/10.1016/j.eurpolymj.2011.07.020	en
heal.language	English	en
heal.publicationDate	2011	en
heal.abstract	We revisit molecular mobility and crystallinity in a series of Polyurethanes prepared with polytetramethylene ether glycol (PTMEG) with varying molecular weights as soft component, methylene diisocyanate (MDI) as diisocyanate component and butanediol as chain extender in close comparison to the properties of the respective macrodiols used as soft segments. Modulated differential scanning calorimetry (MDSC) was utilized to study the glass transition and in detail crystallization and melting. Thermally stimulated depolarization currents (TSDC), and dielectric relaxation spectroscopy (DRS) were used to investigate local dynamics, dynamic glass transition and indirectly, crystallinity and morphology. The dielectric data were evaluated through representation by contour plots in the Arrhenius plane. Glass transition temperature of the diols is practically unaffected by molecular weight due to H-bonding effect, while for the PUs it showed a decreasing dependence due to higher microphase separation. Results are also discussed in terms of fragility. Crystallization of PTMEG becomes more intense and stable with increasing molecular weight, while the reflection of its melting process on its dielectric response was also observed. A weak crystallization process in the Polyurethane with long soft segments was well resolved using MDSC. Evidence for the occurrence of spinodal decomposition before this crystallization was observed by means of DRS. (C) 2011 Elsevier Ltd. All rights reserved.	en
heal.publisher	PERGAMON-ELSEVIER SCIENCE LTD	en
heal.journalName	European Polymer Journal	en
dc.identifier.doi	10.1016/j.eurpolymj.2011.07.020	en
dc.identifier.isi	ISI:000297449600009	en
dc.identifier.volume	47	en
dc.identifier.issue	11	en
dc.identifier.spage	2120	en
dc.identifier.epage	2133	en