Aging of thin polymer films cast from a near-theta solvent
Adam Raegen, Mithun Chowdhury, Christophe Calers, Alexander Schmatulla, Ullrich Steiner, and Günter Reiter. Phys. Rev. Letters 105, 227801 (2010)
Abstract
We have examined the aging behavior of spin-cast thin polymer films as a function of their processing history. Films prepared from solutions close to the theta-temperature were aged for varying times at room temperature, followed by a dewetting experiment above the glass transition temperature of the polymer. The characteristic aging time varied strongly with the quality of the solvent, which is attributed to distorted chain conformations in the as-cast films. This is an indication for the non-equilibrium nature of thin polymer films, possibly causing some of their unexplained properties.