Ultrastable Polymer Glass*

Stable glasses prepared by vapour deposition are an analogue of glassy materials aged for geological time scales. We report the preparation and characterization of stable glasses of polymers (polystyrene and poly (methyl methacrylate) prepared by physical vapour deposition. By controlling substrate temperature, deposition rate, polymerization index and polydispersity, we prepare and characterize a variety of stable polymer glasses. These materials display the kinetic stability, low fictive temperatures and high density characteristic of stable glasses. Extrapolation of measured transformation times between the stable and normal glass provides estimates of the relaxation times of the equilibrium supercooled liquid as much as 30 K below the glass transition temperature. We will also discuss the difference between local relaxations in normal and stable polymer glass as well as promising results making stable polymer network glass.