Kinetics of isothermal and non-isothermal crystallization of poly(vinylidene fluoride) by fast scanning calorimetry

Crystallization from melt of poly(vinylidene fluoride) was studied by thin film chip calorimetry at cooling rates from 500 to 100,000 Ks−1 and isothermally down to 76 °C. At ca. 70 °C, for cooling rates higher than 2000 Ks−1, there appears a change in crystallization from high temperature α phase to...

Ausführliche Beschreibung

Gespeichert in:
Bibliographische Detailangaben
Veröffentlicht in:Polymer (Guilford) 2016-01, Vol.82, p.40-48
Hauptverfasser: Gradys, A., Sajkiewicz, P., Zhuravlev, E., Schick, C.
Format: Artikel
Sprache:eng
Schlagworte:
Online-Zugang:Volltext
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
Beschreibung
Zusammenfassung:Crystallization from melt of poly(vinylidene fluoride) was studied by thin film chip calorimetry at cooling rates from 500 to 100,000 Ks−1 and isothermally down to 76 °C. At ca. 70 °C, for cooling rates higher than 2000 Ks−1, there appears a change in crystallization from high temperature α phase to low temperature β phase. The amorphous state is preserved at cooling rate 100,000 Ks−1. Analysis of the crystallization kinetics with Ziabicki model reveals maximum of the steady-state crystallization rate of β phase as 2200 s−1 at 22 °C, and the highest crystallization rate of α phase as 200 s−1 at 70 °C. Approximation of the temperature dependent steady-state crystallization rate with the Turnbull and Fisher nucleation model results in the equilibrium melting temperatures 227 and 173 °C for the α and β phase, respectively, and in the energy barrier for short-distance transport, ED, as 70–80 kJ mol−1 at high supercooling. [Display omitted] •Melt crystallization at ultra-high cooling rates using thin-film chip calorimetry.•Steady-state crystallization rate of the α and β phase obtained with Ziabicki model.•Approximation of the rate with the Turnbull and Fisher nucleation theory.•Equilibrium melting temperatures and the energy barrier for short-distance transport.
ISSN:0032-3861
1873-2291
DOI:10.1016/j.polymer.2015.11.020