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Titolo:
COMPARATIVE-STUDY OF MECHANICAL AND ELECTRICAL RELAXATIONS IN POLY(ETHERIMIDE) - PART 1
Autore:
BELANA J; CANADAS JC; DIEGO JA; MUDARRA M; DIAZCALLEJA R; FRIEDERICHS S; JAIMES C; SANCHIS MJ;
Indirizzi:
UNIV POLITECN VALENCIA,ETSII,DEPT TERMODINAM E-46071 VALENCIA SPAIN UNIV POLITECN VALENCIA,ETSII,DEPT TERMODINAM E-46071 VALENCIA SPAIN UNIV POLITECN CATALUNYA,ETSEIT,DEPT FIS ENGN NUCL BARCELONA 08222 SPAIN
Titolo Testata:
Polymer international
fascicolo: 1, volume: 46, anno: 1998,
pagine: 11 - 19
SICI:
0959-8103(1998)46:1<11:COMAER>2.0.ZU;2-#
Fonte:
ISI
Lingua:
ENG
Soggetto:
BISPHENOL-A POLYCARBONATE; GLASS-TRANSITION; CONFORMATIONAL FEATURES; SIDE-GROUPS; POLYMERS; BEHAVIOR; BLENDS;
Keywords:
POLY(ETHERIMIDE); THERMALLY STIMULATED DEPOLARIZATION CURRENT; DIELECTRIC LOSS; DYNAMIC MECHANICAL THERMAL ANALYSIS; RELAXATION; ACTIVATION ENERGIES;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Science Citation Index Expanded
Citazioni:
25
Recensione:
Indirizzi per estratti:
Citazione:
J. Belana et al., "COMPARATIVE-STUDY OF MECHANICAL AND ELECTRICAL RELAXATIONS IN POLY(ETHERIMIDE) - PART 1", Polymer international, 46(1), 1998, pp. 11-19

Abstract

Relaxations in poly(etherimide) PEI Ultem 1000 have been analysed by differential scanning calorimetry (DSC), dynamic mechanical spectroscopy (DMS), dielectric relaxation spectroscopy (DRS) and thermally stimulated depolarization current (TSDC) measurements. DMTA and DRS resultsshow three distinct relaxations gamma, beta and alpha in the temperature range -140 to 250 degrees C. The first one depends strongly on thewater content in the sample as will be discussed in more detail in the second paper of this series. These results are in good agreement with those observed by TSDC of conventionally polarized electrets. In addition to these three relaxations, TSDC measurements show: (1) a peak (rho) at which is attributed to space charge temperatures above the alpha relaxation, (2) indications of structure in the beta relaxation zone. In the case of electrets formed by the windowing polarization method, the resulting TSDC spectra allow us to discern the fine structure of the beta relaxation, which is formed by three subrelaxations. In this work, the activation energies calculated by the different techniquesare compared, and a molecular origin for each relaxation is proposed. (C) 1998 SCI.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 04/07/20 alle ore 12:01:36