Influence of backbone rigidity on the curing and the dielectric relaxations of unsaturated polyesters

Simitzis, J; Triantou, D; Soulis, S; Tsangaris, G; Zoumpoulakis, L; Manolopoulos, E

dc.contributor.author	Simitzis, J	en
dc.contributor.author	Triantou, D	en
dc.contributor.author	Soulis, S	en
dc.contributor.author	Tsangaris, G	en
dc.contributor.author	Zoumpoulakis, L	en
dc.contributor.author	Manolopoulos, E	en
dc.date.accessioned	2014-03-01T01:35:52Z
dc.date.available	2014-03-01T01:35:52Z
dc.date.issued	2011	en
dc.identifier.issn	0021-8995	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/21224
dc.subject	dielectric spectroscopy	en
dc.subject	DSC	en
dc.subject	FTIR	en
dc.subject	relaxations	en
dc.subject	swelling	en
dc.subject	unsaturated polyesters	en
dc.subject.classification	Polymer Science	en
dc.subject.other	Adipic acids	en
dc.subject.other	Diffusion parameters	en
dc.subject.other	Double bonds	en
dc.subject.other	DSC	en
dc.subject.other	FTIR	en
dc.subject.other	High frequency	en
dc.subject.other	Low frequency	en
dc.subject.other	Maleate	en
dc.subject.other	Maleic acids	en
dc.subject.other	Molar ratio	en
dc.subject.other	Phthalic anhydrides	en
dc.subject.other	relaxations	en
dc.subject.other	Spectroscopy measurements	en
dc.subject.other	Tetra-hydrofuran	en
dc.subject.other	Unsaturated polyester	en
dc.subject.other	Curing	en
dc.subject.other	Dielectric devices	en
dc.subject.other	Dielectric spectroscopy	en
dc.subject.other	Differential scanning calorimetry	en
dc.subject.other	Esters	en
dc.subject.other	Fourier transforms	en
dc.subject.other	Glass transition	en
dc.subject.other	Polyesters	en
dc.subject.other	Styrene	en
dc.subject.other	Fourier transform infrared spectroscopy	en
dc.title	Influence of backbone rigidity on the curing and the dielectric relaxations of unsaturated polyesters	en
heal.type	journalArticle	en
heal.identifier.primary	10.1002/app.33295	en
heal.identifier.secondary	http://dx.doi.org/10.1002/app.33295	en
heal.language	English	en
heal.publicationDate	2011	en
heal.abstract	Unsaturated polyesters with maleic acid and different molar ratio of phthalic anhydride to adipic acid were produced, mixed with styrene, and cured. The degree of double bonds conversion, determined by differential scanning calorimetry (alpha(DSC)), indicating the initial curing, increases significantly with the molar ratio of phthalic anhydride. On the other hand, the degree of double bonds conversion of maleate (alpha(UP,FTIR)) and styrene (alpha(St,FTIR)) units determined by Fourier transform infrared spectroscopy after prolonged curing are considerably higher than alpha(DSC) and increase slightly with the molar ratio of phthalic anhydride. Polyester containing phthalic anhydride without adipic acid (M5P5) has the lowest tetrahydrofuran uptake and diffusion parameter D/alpha(2) due to its more rigid segments, in opposite to polyester containing adipic acid (M5A5) having the highest values. According to dielectric spectroscopy measurements, two different relaxations were determined, one beginning above 130 degrees C (with peak above 180 degrees C) attributed to alpha-relaxation (dielectric glass transition) and a second one at lower temperatures, attributed to beta-relaxation. The peak of beta-relaxation is at around 130, 75-80, and 30 degrees C for the rigid, intermediate rigidity/flexibility, and flexible polyesters, respectively. The alpha-relaxation is determined at low frequencies and the beta-relaxation at intermediate or high frequencies. (c) 2010 Wiley Periodicals, Inc. J Appl Polym Sci 120: 1984-1993, 2011	en
heal.publisher	WILEY-BLACKWELL	en
heal.journalName	Journal of Applied Polymer Science	en
dc.identifier.doi	10.1002/app.33295	en
dc.identifier.isi	ISI:000288337400014	en
dc.identifier.volume	120	en
dc.identifier.issue	4	en
dc.identifier.spage	1984	en
dc.identifier.epage	1993	en