Temperature dependence of the characteristic length scale for glassy dynamics: Combination of dielectric and specific heat spectroscopy

Allisson Saiter (1) , L. Delbreilh (1) , H. Couderc (1) , K. Arabeche (1) , A. Schönhals (2) , J.-M. Saiter (1)

1 AMME-LECAP EA 4528 International Laboratory - Laboratoire d’Etude et de Caractérisation des Amorphes et des Polymères
2 BAM Federal Institute for Materials Research and Testing

The temperature dependence of characteristic length scales associated to the glass transition such as the cooperativity length scale introduced by Adam and Gibbs cooperative rearranging region CRR or the dynamic heterogeneity as estimated from the four point correlation function 4 , is at the center of large interests. Broadband dielectric spectroscopy and temperature modulated differential scanning calorimetry allow to study the CRR size temperature dependence in the temperature range of ergodicity loss for glass-forming liquids, starting from the onset of cooperativity in the crossover region down to the glass transition temperature. Furthermore, the correlation between these two techniques allows to explore a large frequency range from 1 mHz to 10 MHz. The goal of this work is to follow the cooperativity evolution along the Arrhenius plot for two different polymeric systems: polyethylene 1,4-cyclohexylenedimethylene terephthalate glycol and polybisphenol A carbonate.

Domaines: Matière Molle [cond-mat.soft]; Science des matériaux [cond-mat.mtrl-sci]

Allisson Saiter, L. Delbreilh, H. Couderc, K. Arabeche, A. Schönhals, et al.. Temperature dependence of the characteristic length scale for glassy dynamics: Combination of dielectric and specific heat spectroscopy. Physical Review E : Statistical, Nonlinear, and Soft Matter Physics, 2010, 81 (4), pp.041805. ⟨10.1103/PhysRevE.81.041805⟩. ⟨hal-02114159⟩