Investigation of the microphase separation in blends of polyurethane-based ionomers

Tsonos, C; Apekis, L; Viras, K; Stepanenko, L; Karabanova, L; Sergeeva, L

dc.contributor.author	Tsonos, C	en
dc.contributor.author	Apekis, L	en
dc.contributor.author	Viras, K	en
dc.contributor.author	Stepanenko, L	en
dc.contributor.author	Karabanova, L	en
dc.contributor.author	Sergeeva, L	en
dc.date.accessioned	2014-03-01T01:15:40Z
dc.date.available	2014-03-01T01:15:40Z
dc.date.issued	2000	en
dc.identifier.issn	0022-2348	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/13658
dc.subject	dielectric spectroscopy	en
dc.subject	micromorphology	en
dc.subject	microphase separation	en
dc.subject	polyurethane-based ionomers	en
dc.subject	polyurethanes	en
dc.subject.classification	Polymer Science	en
dc.subject.other	INTERPENETRATING POLYMER NETWORKS	en
dc.subject.other	STRUCTURE-PROPERTY RELATIONSHIPS	en
dc.subject.other	BLOCK-COPOLYMERS	en
dc.subject.other	SEGMENTED POLYURETHANES	en
dc.subject.other	CATIONOMERS	en
dc.subject.other	MORPHOLOGY	en
dc.subject.other	WATER	en
dc.title	Investigation of the microphase separation in blends of polyurethane-based ionomers	en
heal.type	journalArticle	en
heal.identifier.primary	10.1081/MB-100100378	en
heal.identifier.secondary	http://dx.doi.org/10.1081/MB-100100378	en
heal.language	English	en
heal.publicationDate	2000	en
heal.abstract	Blends of an anion containing polyurethane (PU1) and polyaminourethane (PU2) were investigated. Dielectric relaxation spectroscopy (DRS), differential scanning calorimetry (DSC), and small-angle X-ray scattering (SAXS) were used in a study of the molecular mobility and microphase morphology and their dependence on the composition of these ionomers. Dielectric thermally stimulated depolarization current (TSDC) measurements of the ionomer blends showed four relaxation mechanisms. The subglass secondary gamma- and beta-relaxations are related to local motions; the alpha-relaxation is related to the glass transition of the amorphous soft phase of the ionomers, and the Maxwell-Wagner-Sillars (MWS) relaxation is related to interfacial polarization caused by the motion of ions released during the glass transition. The alpha- and MWS TSDC relaxations are strongly affected by the degree of microphase segregation (DMS) of the ionomer blends. Based on TSDC measurements, the parameter m(TSDC), a criterion expressing a relative degree of phase mixing, is introduced. According to this parameter, the classification of the investigated ionomer blends, in order of decreasing phase mixing (PU1/PU2 in %) is 50/50 (mixed) > 0/100 > 5/95 > 10/90 > 100/0 > 30/70 (high separation). It appears that, as a result of the complexity of the systems, their structures and their properties are not simple functions of their composition. SAXS measurements show that pure PU1 ionomer has a high degree of microphase separation. The introduction of PU2 in the blend causes defects in the hard domains and leads to a structure with mixing of the soft and hard microphases. SAXS measurements concerning DMS are in good agreement with the TSDC results and support the introduced criterion of the relative degree of phase mixing.	en
heal.publisher	MARCEL DEKKER INC	en
heal.journalName	JOURNAL OF MACROMOLECULAR SCIENCE-PHYSICS	en
dc.identifier.doi	10.1081/MB-100100378	en
dc.identifier.isi	ISI:000085761100003	en
dc.identifier.volume	B39	en
dc.identifier.issue	2	en
dc.identifier.spage	155	en
dc.identifier.epage	174	en