Polymer dynamics in polyurethane/clay nanocomposites studied by dielectric and thermal techniques

Kripotou, S; Pissis, P; Savelyev, YV; Robota, LP; Travinskaya, TV

dc.contributor.author	Kripotou, S	en
dc.contributor.author	Pissis, P	en
dc.contributor.author	Savelyev, YV	en
dc.contributor.author	Robota, LP	en
dc.contributor.author	Travinskaya, TV	en
dc.date.accessioned	2014-03-01T01:34:18Z
dc.date.available	2014-03-01T01:34:18Z
dc.date.issued	2010	en
dc.identifier.issn	0022-2348	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/20687
dc.subject	Dielectric relaxation	en
dc.subject	Glass transition	en
dc.subject	Immobilized polymer	en
dc.subject	Polymer dynamics	en
dc.subject	Polyurethane/clay nanocomposites	en
dc.subject.classification	Polymer Science	en
dc.subject.other	Broadband dielectric relaxation spectroscopy	en
dc.subject.other	Chain extenders	en
dc.subject.other	Dimethylhydrazine	en
dc.subject.other	Diphenylmethane diisocyanate	en
dc.subject.other	Glass transition dynamics	en
dc.subject.other	Good correlations	en
dc.subject.other	matrix	en
dc.subject.other	Microphase-separated structure	en
dc.subject.other	Morphology and dynamics	en
dc.subject.other	Organically modified montmorillonite	en
dc.subject.other	Polymer dynamics	en
dc.subject.other	Polyurethane/clay nanocomposites	en
dc.subject.other	Solution casting	en
dc.subject.other	Thermal techniques	en
dc.subject.other	Thermally stimulated depolarization currents	en
dc.subject.other	Weight fractions	en
dc.subject.other	Wide angle X-ray scattering	en
dc.subject.other	Clay minerals	en
dc.subject.other	Dielectric relaxation	en
dc.subject.other	Differential scanning calorimetry	en
dc.subject.other	Glass	en
dc.subject.other	Glycols	en
dc.subject.other	Mechanical properties	en
dc.subject.other	Nanocomposites	en
dc.subject.other	Reconnaissance aircraft	en
dc.subject.other	Silicate minerals	en
dc.subject.other	Spectroscopy	en
dc.subject.other	Vibrations (mechanical)	en
dc.subject.other	Glass transition	en
dc.title	Polymer dynamics in polyurethane/clay nanocomposites studied by dielectric and thermal techniques	en
heal.type	journalArticle	en
heal.identifier.primary	10.1080/00222340903344309	en
heal.identifier.secondary	http://dx.doi.org/10.1080/00222340903344309	en
heal.language	English	en
heal.publicationDate	2010	en
heal.abstract	Differential scanning calorimetry (DSC), broadband dielectric relaxation spectroscopy (DRS), and thermally stimulated depolarization current (TSDC) techniques were employed to investigate glass transition and polymer dynamics in nanocomposites of polyurethane (PU) and organically modified montmorillonite (MMT) (weight fraction 0%-15%) prepared by solution casting. The PU matrix was obtained from oligo(oxytetramethylene glycol) of molar mass 1000 g/mol, 4,4'-diphenylmethane diisocyanate and 1,1-dimethylhydrazine as chain extender. Wide-angle X-ray scattering confirmed the formation of partly exfoliated structures at low MMT content. DSC, DRS, and TSDC show, in agreement with each other, that a fraction of polymer makes no contribution to the glass transition and to the corresponding relaxation, whereas the rest exhibits similar glass transition dynamics as the pure matrix. This fraction of immobilized polymer reaches a maximum at about 5 wt% MMT. Effects of MMT on the microphase-separated structure of PU are negligible, as indicated by the study of glass transition and interfacial dielectric polarization/relaxation. No effects of MMT on the local, secondary and relaxations were observed. Mechanical properties show a maximum improvement at about 5 wt% MMT, in good correlation with morphology and dynamics.	en
heal.publisher	TAYLOR & FRANCIS INC	en
heal.journalName	Journal of Macromolecular Science, Part B: Physics	en
dc.identifier.doi	10.1080/00222340903344309	en
dc.identifier.isi	ISI:000273632100008	en
dc.identifier.volume	49	en
dc.identifier.issue	1	en
dc.identifier.spage	86	en
dc.identifier.epage	110	en