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

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 $\Delta T$ ($\le$ 20 K)between two temperatures, $T_1$ and $T_2$. A crossover from cumulative aging to non-cumulative aging could be observed with increasing $\Delta T$ 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.

arXiv comment7 pages, 6 figures

References in corpus (10)

• Glass transitions and dynamics in thin polymer films: dielectric relaxation of thin films of polystyrene
• Memory and Chaos Effects in Spin Glasses
• Glassy Aging Dynamics
• Slow dynamics near glass transitions in thin polymer films
• Dynamics of alpha- and beta- processes in thin polymer films: poly(vinyl acetate) and poly(methyl methacrylate)
• Symmetrical Temperature-Chaos Effect with Positive and Negative Temperature Shifts in a Spin Glass
• Aging phenomena in PMMA thin films -- memory and rejuvenation effects
• Advanced memory effects in the aging of a polymer glass
• Fragility of the Free-Energy Landscape of a Directed Polymer in Random Media
• Temperature Cycles in the Heisenberg Spin Glass