Dielectric loss spectra of ethylbenzene in the temperature range of 116–134 K, recorded in steps of 2 K. The amplitude reduction seen for the three highest temperatures is irreversible and due to crystallization.
Activation plot for the maximum relaxation time of the primary relaxation of EBZ. The filled circles are the dielectric measurement data in this work, the solid line is the VFT fit. The inset shows the temperature dependence of the inverse square root of the derivative, [−dlogτ/dT]−1/2, where the open triangles represent the case derived from the viscosity data taken from Barlow et al. (Ref. 23) and from Rossini (Ref. 39). The solid and dashed lines in the inset are the VFT fits for the low and high temperature ranges, respectively. The arrow indicates the crossover temperature.
Activation plots for ααβ-trisnaphthylbenzene (TNB), indomethacin (IMC), toluene (TOL), ethylbenzene (EBZ), n-propylbenzene (NPB), iso-propylbenzene (IPB), and ethylcyclohexane (ECH). In the order of the figure legends and decreasing T g, the data sources are: TNB: dielectric (Ref. 27), viscosity (Ref. 28); IMC: dielectric (Ref. 29); IPB: dielectric (Refs. 30 and 31), viscosity (Ref. 23); NPB: dielectric (Refs. 30 and 32), viscosity (Refs. 23 and 33); TOL: dielectric (Ref. 34), viscosity (Ref. 23), spin alignment (Refs. 35 and 36), deuteron-T1 (Ref. 36), microwave spectroscopy (Ref. 37), nuclear magnetic resonance (Ref. 38); EBZ: dielectric (this work), viscosity (Refs. 23 and 39); ECH: dielectric (Refs. 40 and 41), viscosity (Refs. 13 and 33).
Angell plot of the relaxation time of TNB, IMC, TOL, EBZ, NPB, IPB, and ECH. The symbols identify different materials, but experimental techniques are not discriminated. The dashed lines represent the VFT fits for ethylcyclohexane (m = 57) and for ethylbenzene (m = 98).
Plots of [−dlogτ/d(T/T g)]−1/2 versus T/T g for TNB, IPB, NPB, TOL, EBZ, and ECH. The dashed lines are guides only, with linear behavior indicating VFT behavior with T 0 given by the intersection with the abscissa. The inset is an enlargement of scales near T g.
Compilation of parameters associated with the T ≤ T B dynamics of the glass-former of this study: glass transition temperature T g, fragility index m, VFT constants A, B, T 0, crossover temperature T B, and the value of G ∞ used to match viscosity to relaxation times using η = τ/G ∞. VFT parameters are based upon data in the T < T B range, both T g and m are derived from the VFT fits.
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