DSC curing study of catalytically synthesized maleic-acid-based unsaturated polyesters

Simitzis, J; Zoumpoulakis, L; Soulis, S

dc.contributor.author	Simitzis, J	en
dc.contributor.author	Zoumpoulakis, L	en
dc.contributor.author	Soulis, S	en
dc.date.accessioned	2014-03-01T01:17:44Z
dc.date.available	2014-03-01T01:17:44Z
dc.date.issued	2002	en
dc.identifier.issn	0959-8103	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/14641
dc.subject	Curing	en
dc.subject	DSC	en
dc.subject	FTIR	en
dc.subject	Maleic acid unsaturated polyesters	en
dc.subject	Polyesterification catalysts	en
dc.subject.classification	Polymer Science	en
dc.subject.other	Activation energy	en
dc.subject.other	Carboxylic acids	en
dc.subject.other	Catalysts	en
dc.subject.other	Curing	en
dc.subject.other	Differential scanning calorimetry	en
dc.subject.other	Fourier transform infrared spectroscopy	en
dc.subject.other	Polyethylene glycols	en
dc.subject.other	Reaction kinetics	en
dc.subject.other	Styrene	en
dc.subject.other	Synthesis (chemical)	en
dc.subject.other	Unsaturated polyesters	en
dc.subject.other	Polyesters	en
dc.subject.other	catalyst	en
dc.subject.other	curing	en
dc.subject.other	polyester	en
dc.subject.other	resin	en
dc.subject.other	unsaturated medium	en
dc.title	DSC curing study of catalytically synthesized maleic-acid-based unsaturated polyesters	en
heal.type	journalArticle	en
heal.identifier.primary	10.1002/pi.832	en
heal.identifier.secondary	http://dx.doi.org/10.1002/pi.832	en
heal.language	English	en
heal.publicationDate	2002	en
heal.abstract	Unsaturated polyesters were synthesized based on ethylene glycol and maleic acid as unsaturated dicarboxylic acid, using a variety of saturated acids in the initial acid mixture, without or with different catalysts. The curing of the polyesters produced with styrene was studied using differential scanning calorimetry (DSC) under dynamic- and isothermal-h eating conditions. The FTIR spectra of the initial polyesters and cured polyesters were also determined. Curing is not complete at the end of DSC scan and the unreacted bonds were quantitatively determined from the FTIR spectra and by estimation based on literature data. The value of the mean degree of conversion (a) of all double bonds (styrene unit and maleate unit) was approximately alpha=0.40. Using an appropriate kinetic model for the curing exotherm of polyesters, the activation energy (E-a), the reaction order (x) and the frequency factor (k(o)) were determined. Because the kinetic parameters (ie E-a, k, x) affect the kinetics in various different ways, the curves of degree of conversion versus time at various isothermal conditions are more useful to compare and characterize the curing of polyesters. The kinetic parameters are mainly influenced by the proportion of maleic acid in the polyesterification reaction mixture and secondarily by the residual polyesterification catalyst. The degree of conversion of already crosslinked polyesters is greatly increased by post-curing them at elevated temperature and for a prolonged time. (C) 2002 Society of Chemical Industry.	en
heal.publisher	JOHN WILEY & SONS LTD	en
heal.journalName	Polymer International	en
dc.identifier.doi	10.1002/pi.832	en
dc.identifier.isi	ISI:000175026200005	en
dc.identifier.volume	51	en
dc.identifier.issue	4	en
dc.identifier.spage	308	en
dc.identifier.epage	318	en