A new energy dispersive x-ray diffraction method was used to observe isothermal phase transitions of a polyethylene oxide sample contained in a variable temperature cell. A series of scattering measurements were performed to follow the time evolution of the system at each temperature. The collected spectra were suitably processed and the transition coordinate x was obtained as a function of time. A detailed treatment of the errors was accomplished to evaluate the reliability of the method. The experimental points (dx/dt)(max) - T were plotted both for the amorphous-crystalline (below the melting temperature T-m) and for the crystalline-amorphous (over T-m) transitions. They reproduce the usual behavior for T < T-m and show a characteristic unexpected feature for T > T-m which is partially justified.

Temperature dependence of PEO phase transition rate by energy dispersive x-ray diffraction

CROCE, Fausto;
1997-01-01

Abstract

A new energy dispersive x-ray diffraction method was used to observe isothermal phase transitions of a polyethylene oxide sample contained in a variable temperature cell. A series of scattering measurements were performed to follow the time evolution of the system at each temperature. The collected spectra were suitably processed and the transition coordinate x was obtained as a function of time. A detailed treatment of the errors was accomplished to evaluate the reliability of the method. The experimental points (dx/dt)(max) - T were plotted both for the amorphous-crystalline (below the melting temperature T-m) and for the crystalline-amorphous (over T-m) transitions. They reproduce the usual behavior for T < T-m and show a characteristic unexpected feature for T > T-m which is partially justified.
File in questo prodotto:
Non ci sono file associati a questo prodotto.

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11564/429915
 Attenzione

Attenzione! I dati visualizzati non sono stati sottoposti a validazione da parte dell'ateneo

Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 9
  • ???jsp.display-item.citation.isi??? 10
social impact