Conformational motions in immiscible blends of polycarbonate and styrene-acrylonitrile copolymers

Belloch, GP; Sanchez, MS; Ribelles, JLG; Pradas, MM; Duenas, JMM; Pissis, P

dc.contributor.author	Belloch, GP	en
dc.contributor.author	Sanchez, MS	en
dc.contributor.author	Ribelles, JLG	en
dc.contributor.author	Pradas, MM	en
dc.contributor.author	Duenas, JMM	en
dc.contributor.author	Pissis, P	en
dc.date.accessioned	2014-03-01T01:14:28Z
dc.date.available	2014-03-01T01:14:28Z
dc.date.issued	1999	en
dc.identifier.issn	0032-3888	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/13092
dc.relation.uri	http://www.scopus.com/inward/record.url?eid=2-s2.0-0032627913&partnerID=40&md5=97902aeb2fd2e5db98e03688bbcdec74	en
dc.subject.classification	Engineering, Chemical	en
dc.subject.classification	Polymer Science	en
dc.subject.other	Annealing	en
dc.subject.other	Chemical bonds	en
dc.subject.other	Copolymers	en
dc.subject.other	Dielectric relaxation	en
dc.subject.other	Ethanol	en
dc.subject.other	Glass transition	en
dc.subject.other	Molecular weight	en
dc.subject.other	Numerical methods	en
dc.subject.other	Oligomers	en
dc.subject.other	Phase composition	en
dc.subject.other	Polycarbonates	en
dc.subject.other	Precipitation (chemical)	en
dc.subject.other	Conformational motions	en
dc.subject.other	Polymer chains	en
dc.subject.other	Styrene acrylonitrile copolymers	en
dc.subject.other	Polymer blends	en
dc.title	Conformational motions in immiscible blends of polycarbonate and styrene-acrylonitrile copolymers	en
heal.type	journalArticle	en
heal.language	English	en
heal.publicationDate	1999	en
heal.abstract	Blends of commercial bisphenol-A-polycarbonate and styrene-acrylonitrile copolymers were prepared by precipitation in ethanol from the solution in methylene chloride in order to eliminate the low molecular weight substances contained in the commercial polymers, specially the oligomers contained in commercial SAN copolymers. Two glass transitions appear in the DSC thermograms of the blend at the same temperatures as in the pure components which, in principle, indicates that the blend consists of two phases formed by pure PC and pure SAN. In order to detect small changes in the glass transition process that could be indicative of different mobility of the polymer chains in the blend with respect to the pure polymers, blends of different compositions were subjected to different thermal treatments that included annealing at temperatures below both glass transitions, and then the DSC thermograms were recorded. A broadening in the peaks shown by the c(p)(T) curves measured on annealed samples in the zone of the PC transition is detected while no significant differences are shown by the glass transition of the SAN phase of the blend with respect to pure SAN copolymer. Dielectric relaxation experiments in the frequency domain (from 100 to 3.10(6)Hz) were carried out on the blends. The dielectric relaxation spectrum in the zone of the SAN main relaxation process was fitted with the stretched exponential equation showing no significant differences between the blends and the pure SAN copolymer. The region of the main relaxation process of PC was not analyzed due to the small polar activity of PC and the overlapping with the relaxation of the SAN phase.	en
heal.publisher	Soc Plast Eng, Brookfield, CT, United States	en
heal.journalName	Polymer Engineering and Science	en
dc.identifier.isi	ISI:000080246000008	en
dc.identifier.volume	39	en
dc.identifier.issue	4	en
dc.identifier.spage	688	en
dc.identifier.epage	698	en