Catalogo Articoli (Spogli Riviste)

OPAC HELP

Titolo:
Analysis of calorimetric curves detected during the polymorphic transformation of isotactic polybutene-1
Autore:
Alfonso, GC; Azzurri, F; Castellano, M;
Indirizzi:
Univ Genoa, Dept Chem & Ind Chem, I-16146 Genoa, Italy Univ Genoa Genoa Italy I-16146 ept Chem & Ind Chem, I-16146 Genoa, Italy
Titolo Testata:
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
fascicolo: 1, volume: 66, anno: 2001,
pagine: 197 - 207
SICI:
1388-6150(2001)66:1<197:AOCCDD>2.0.ZU;2-0
Fonte:
ISI
Lingua:
ENG
Soggetto:
PHASE-TRANSFORMATION; CRYSTALLIZATION; BEHAVIOR; BLENDS;
Keywords:
DSC analysis; i-polybutene-1; kinetics; polymorphic transformation;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Physical, Chemical & Earth Sciences
Citazioni:
37
Recensione:
Indirizzi per estratti:
Indirizzo: Alfonso, GC Univ Genoa, Dept Chem & Ind Chem, Via Dodecaneso 31, I-16146 Genoa, Italy Univ Genoa Via Dodecaneso 31 Genoa Italy I-16146 Genoa, Italy
Citazione:
G.C. Alfonso et al., "Analysis of calorimetric curves detected during the polymorphic transformation of isotactic polybutene-1", J THERM ANA, 66(1), 2001, pp. 197-207

Abstract

Multiple endotherms detected on heating melt-crystallized i-polybutene-1 (PBu-1) are associated to the polymorphic transformation from the tetragonal(Form II) to the hexagonal modification (Form I). During this transformation, a progressive increase of the intensity of the high temperature endotherm, at the expenses of that pertaining to the low temperature one, is observed in DSC heating curves. Depending on molecular characteristics of the constituent chains and crystallization conditions, the two endotherms may exhibit some extent of superposition. In these cases, a reliable procedure to analyze the whole thermal curve must be found and adopted in order to follow the progress of the transformation in quantitative terms. The same set of thermal curves, detected after various ageing times of melt-crystallized i-PBu-1, has been analyzed according to four different approaches. Comparison of the results shows that, with the exception of the analysis based on the 'partial area' routine, available to most instruments, all methods lead to equivalent results. The simplest approach, based on the mass balance during structural transformation, should be preferred whenever constant overall degree of crystallinity can be assumed throughout the whole process.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 13/07/20 alle ore 18:10:20