Comparison of Physical Aging and Glass Transition in Glassy-Rubbery Polymer Bilayer Films.

In the present work, we use ellipsometry to extract the physical aging response of thin glassy polystyrene (PS) layers from rubbery-glassy bilayer films of poly(-butyl methacrylate) (PnBMA) atop PS. How the soft interface between rubbery and glassy polymer domains can impact the physical aging response of glassy domains is unclear. Measurements in the literature have shown that the local glass transition temperature of PS is strongly reduced near a PnBMA/PS interface with a magnitude twice as large compared to that imparted by a free surface.