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3. THE GLASS STATE AND THE GLASS TRANSITION : THERMODYNAMIC and KINETIC ASPECTS

3. THE GLASS STATE AND THE GLASS TRANSITION : THERMODYNAMIC and KINETIC ASPECTS. Differential Scanning Calorimetry. Differential Thermal Analysis. Is the glass transition a true thermodynamic phase transition ?.  T g depends on the cooling rate

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3. THE GLASS STATE AND THE GLASS TRANSITION : THERMODYNAMIC and KINETIC ASPECTS

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  1. 3. THE GLASS STATE AND THE GLASS TRANSITION: THERMODYNAMIC and KINETIC ASPECTS

  2. Differential Scanning Calorimetry Differential Thermal Analysis

  3. Is the glass transition a true • thermodynamic phase transition ?  Tg depends on the cooling rate  Tg depends on the thermal history

  4. sub-Tg aging and annealing Tanneal .

  5. Phase transitions of 1st and 2nd order (Ehrenfest classification) Clausius-Clapeyron Ehrenfest

  6. Phase transitions of 1st and 2nd order (Ehrenfest classification)

  7. 1st-order, 2nd-order and Lambda-type transitions [ T1=T2 ; P1=P2 ; g1=g2 ] v1=v2 s1=s2 cp1  cp2 1  2 T1  T2 v1  v2 s1  s2 cp, , T   v1=v2 s1=s2 cp, , T  

  8. Ehrenfest relations Prigogine-Defay ratio must be = 1 if it were a phase transition with a single order parameter

  9. using Differential Scanning Calorimetry (DSC, TMDSC…) [J. M. Hutchinson, Thermochimica Acta 324 (1998) 165-174

  10. using Differential Scanning Calorimetry

  11. the fictive temperature Tf B2O3 [M. A. R. et al., J. Non-Cryst. Solids 221 (1997) 170]

  12. the fictive temperature Tf Ethanol [B. Kabtoul and M. A. R., Phys. Status Solidi A 208, 2249–2253 (2011)]

  13. the fictive temperature Tf  phenomenological Tool-Narayanaswamy-Moynihan (TNM) approach [ Tool, J. Am. Ceram. Soc. 29 (1946) 240. Narayanaswamy, J. Am. Ceram. Soc. 54 (1971) 491. Moynihan et al., J. Am. Ceram. Soc. 59 (1976) 12. ] • curve fitting method: • [I. M. Hodge, J. Non-Cryst. Solids 169 (1994) 211]

  14. THE KAUZMANN PARADOX EXCESS OF ENTROPY: TK

  15. W. Kauzmann, Chem. Rev.43, 219 (1948)

  16. THE KAUZMANN PARADOXNN 1.0

  17. STRONG AND FRAGILE GLASS-FORMING LIQUIDS 0 1

  18. Vogel-Tamman-Fulcher equation: (D: strength) fragility index m:

  19. STRONG AND FRAGILE GLASS-FORMING LIQUIDS C. A. Angell, J. Non-Cryst. Solids 102, 205 (1988)

  20. [I. Chang and H. Sillescu] Stokes-Einstein equation: [A. Einstein, Annalen der Physik 17, 549 (1905)]

  21. B2O3 v  o-terphenyl H

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