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arXiv · 1803.03671

Unique dynamic crossover in supercooled x,3-dihydroxypropyl acrylate (x = 1, 2) isomers mixture

Szymon Starzonek·Aleksandra Kędzierska-Sar·Aleksandra Drozd-Rzoska·Mikołaj Szafran·Sylwester J. Rzoska
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Abstract

The previtreous dynamics in glass forming monomer, glycerol monoacrylate (GMA), using broadband dielectric spectroscopy (BDS) was tested. Measurements revealed the clear dynamic crossover at temperature $T_B = 254$ K and the time scale $\tau(T_B) = 5.4$ ns for the primary (structural) relaxation time and no hallmarks for the crossover for the DC electric conductivity $\sigma_{DC}$. This result was revealed via the derivative-based and distortions-sensitive analysis $dln{H_{a}}/d(1/T)$ vs. $1/T$, where $H_a$ is for the apparent activation energy. Subsequent tests of the fractional Debye-Stokes-Einsten relation $\sigma_{DC}(\tau_{\alpha})^S = const$ showed that the crossover is associated with $S = 1$ (for $T>T_B$)->$S = 0.84$ (for $T<T_B$). The crossover is associated with the emergence of the secondary beta relaxation which smoothly develops deeply into the solid amorphous phase below the glass temperature $T_g$.

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Szymon Starzonek, Aleksandra Kędzierska-Sar, Aleksandra Drozd-Rzoska, Mikołaj Szafran, Sylwester J. Rzoska. 2018-03-09. Unique dynamic crossover in supercooled x,3-dihydroxypropyl acrylate (x = 1, 2) isomers mixture. https://arxiv.org/abs/1803.03671

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