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Secondary relaxation processes glass transition temperatures measured

Abstract The present study demonstrates, by means of broadband dielectric measurements, that the primary a- and the secondary Johari-Goldstein (JG) /3-processes are strongly correlated, in contrast with the widespread opinion of statistical independence of these processes. This occurs for different glassforming systems, over a wide temperature and pressure range. In fact, we found that the ratio of the a- and P- relaxation times is invariant when calculated at different combinations of P and T that maintain either the primary or the JG relaxation times constant. The a-P interdependence is quantitatively confirmed by the clear dynamic scenario of two master curves (one for a-, one for P-relaxation) obtained when different isothermal and isobaric data are plotted together versus the reduced variable Tg(P)/T, where Tg is the glass transition temperature. Additionally, the a-P mutual dependence is confirmed by the overall superposition of spectra measured at different T-P combinations but with an invariant a-relaxation time. [Pg.40]


See other pages where Secondary relaxation processes glass transition temperatures measured is mentioned: [Pg.245]    [Pg.536]    [Pg.45]    [Pg.359]    [Pg.229]    [Pg.58]    [Pg.228]    [Pg.127]    [Pg.60]    [Pg.121]    [Pg.6]    [Pg.213]    [Pg.252]    [Pg.497]    [Pg.234]    [Pg.125]   


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Glass measurement

Glass relaxation

Glass transition process

Glass transition temperature secondary

Glass transition temperature, measurement

Process measures

Process temperature measurement

Process temperatures

Processing temperatures

Relaxation glass transition temperature

Relaxation measurements

Relaxation process

Relaxation processes measurement

Relaxation processes, glass transition

Relaxation secondary

Relaxation temperatures

Relaxation transition

Secondary glass relaxation

Secondary measurements

Secondary processes

Secondary processing

Secondary relaxation processes

Secondary transitions

Temperature measurement

Temperature measuring (process

Transition processes

Transition temperatures, measuring

Transitional measures

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