The Polymer Society of Korea

Abstract

We demonstrated that solvent annealing induces crystallization in 100 nm-thick polycarbonate films, resulting in enhanced mechanical properties with increasing annealing time. This enhancement is attributed to the formation of crystalline structures on the film surface. During the early stages of crystallization, mechanical properties—including Young’s modulus, tensile strength, and toughness—exhibited noticeable fluctuations. Stable mechanical behavior was achieved after 9 h of solvent annealing, when the film surface became fully covered by crystalline structures. Furthermore, uniform shear band formation was observed during tensile deformation of the crystallized films, accompanied by significantly improved mechanical performance. The solvent annealing process presented here provides a feasible strategy for achieving high mechanical performance in polymer thin films while maintaining nanometer-scale thickness.