Molecular dynamics in homo, diblock and triblock polymers studied by dielectric relaxation spectroscopy

Kyritsis, A; Pissis, P; Konsta, A; Mai, SM; Booth, C

dc.contributor.author	Kyritsis, A	en
dc.contributor.author	Pissis, P	en
dc.contributor.author	Konsta, A	en
dc.contributor.author	Mai, SM	en
dc.contributor.author	Booth, C	en
dc.date.accessioned	2014-03-01T01:15:43Z
dc.date.available	2014-03-01T01:15:43Z
dc.date.issued	2000	en
dc.identifier.issn	1070-9878	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/13679
dc.subject	Critical Value	en
dc.subject	Dielectric Relaxation	en
dc.subject	Glass Transition	en
dc.subject	Length Scale	en
dc.subject	Molecular Dynamic	en
dc.subject	Normal Modes	en
dc.subject.classification	Engineering, Electrical & Electronic	en
dc.subject.classification	Physics, Applied	en
dc.subject.other	NORMAL MODE PROCESS	en
dc.subject.other	CIS-POLYISOPRENE	en
dc.subject.other	BULK SYSTEMS	en
dc.subject.other	COPOLYMERS	en
dc.subject.other	BEHAVIOR	en
dc.title	Molecular dynamics in homo, diblock and triblock polymers studied by dielectric relaxation spectroscopy	en
heal.type	journalArticle	en
heal.identifier.primary	10.1109/94.868070	en
heal.identifier.secondary	http://dx.doi.org/10.1109/94.868070	en
heal.language	English	en
heal.publicationDate	2000	en
heal.abstract	The dynamics of poly(oxybutylene) chains was investigated in comparison to that of poly(oxybutylene) blocks in solid semicrystalline poly(oxyethylene)-poly(oxybutylene) (EB) diblock copolymers and poly(oxyethylene)-poly(oxybutylene)-poly (EBE) triblock copolymers, using broadband dielectric relaxation spectroscopy (10(-2) to 10(9) Hz). The B homopolymers and the B blocks of the triblocks were dipole-inverted, whereas no dipole inversion occurred in the B blocks of the diblocks. For B blocks longer than a critical value B-cr, the main relaxation, which is related to the glass transition, exhibits similar characteristics in all three systems. The normal mode relaxation process due to chain motions of larger length scales than that of segmental motion, also was studied for the homopolymers and the copolymers. The results also imply that B blocks of triblock copolymers exhibit normal mode relaxation, where mainly normal eigenmodes of relatively high orders contribute. The mobility of the global chain motion is determined by the order of the normal eigenmodes with the highest intensities, whereas the whole chain conformations are mainly determined by the spatial confinement in the solid copolymers and the effects of fixed chain ends, irrespectively of the order of the most intensive eigenmodes. For very short B blocks, fixed chain end effects affect significantly the dynamics of both, main and normal mode relaxation.	en
heal.publisher	IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC	en
heal.journalName	IEEE TRANSACTIONS ON DIELECTRICS AND ELECTRICAL INSULATION	en
dc.identifier.doi	10.1109/94.868070	en
dc.identifier.isi	ISI:000089337100010	en
dc.identifier.volume	7	en
dc.identifier.issue	4	en
dc.identifier.spage	509	en
dc.identifier.epage	516	en