Glassy dynamics in thin films of polystyrene

TL;DR

This study investigates the aging and memory effects in thin polystyrene films through dielectric spectroscopy, revealing volume and permittivity changes during aging and demonstrating memory and rejuvenation phenomena.

Contribution

It provides new insights into the dielectric aging, memory, and rejuvenation effects in polystyrene thin films, expanding understanding of glassy dynamics in polymers.

Findings

Real part of capacitance increases with aging time

Imaginary part of capacitance decreases with aging time

Memory and rejuvenation effects observed in dielectric permittivity

Abstract

Glassy dynamics was investigated for thin films of atactic polystyrene by complex electric capacitance measurements using dielectric relaxation spectroscopy. During the isothermal aging process the real part of the electric capacitance increased with time, whereas the imaginary part decreased with time. It follows that the aging time dependences of real and imaginary parts of the electric capacitance were primarily associated with change in volume (film thickness) and dielectric permittivity, respectively. Further, dielectric permittivity showed memory and rejuvenation effects in a similar manner to those observed for poly(methyl methacrylate) thin films. On the other hand, volume did not show a strong rejuvenation effect.