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arXiv · 0801.0794

Crossover of aging dynamics in polymer glass: from cumulative aging to non-cumulative aging

Koji Fukao·Sinpei Yamawaki
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Abstract

The aging behavior of polymer glass, poly(methyl methacrylate), has been investigated through the measurement of ac dielectric susceptibility ata fixed frequency after a temperature shift $ΔT$ ($\le $ 20 K)between two temperatures, $T_1$ and $T_2$. A crossover from cumulative aging to non-cumulative aging could be observed with increasing $ΔT$ using a twin temperature ($T$-) shift measurement. Based on a growth law of a dynamical coherent length given by activated dynamics, we obtained a unique coherent length for positive and negative $T$-shifts. The possibility of the existence of temperature chaos in polymer glasses is discussed.

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Koji Fukao, Sinpei Yamawaki. 2008-01-05. Crossover of aging dynamics in polymer glass: from cumulative aging to non-cumulative aging. https://doi.org/10.1103/physreve.76.021507

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