Relaxation Dynamics of Rubbed Polystyrene Thin Films
Glass Transition Temperature, Polymer Films, Surface, Interface, Behavior
Optical retardation measurements were used to probe the chain relaxation dynamics in rubbed polystyrene films of varying thicknesses on glass substrates. A model based on Kohlrausch-Williams-Watts relaxation was developed and used to determine the glass transition temperature (Tg) of the films. Results showed reductions of 15–20 K in Tg for thin films of thicknesses comparable to the radius of gyration as well as for cast films rubbed with different strengths. These results provide evidence of a faster relaxation dynamics relative to the polymer-substrate interface for thinner films and enhanced chain mobility at the polymer-air interface.
Agra, D. M. G.; Schwab, A. D.; Kim, J-H.; Kumar, Satyendra; and Dhinojwala, A. (2000). Relaxation Dynamics of Rubbed Polystyrene Thin Films. Europhysics Letters 51(6), 655-660. doi: 10.1209/epl/i2000-00388-9 Retrieved from http://digitalcommons.kent.edu/phypubs/90