Role of α and β relaxations in Collapsing Dynamics of a Polymer Chain in Supercooled Glass-forming Liquid

Understanding the effect of glassy dynamics on the stability of bio-macromolecules and investigating the underlying relaxation processes governing degradation processes of these macromolecules are of immense importance in the context of bio-preservation. In this work we have studied the stability of a model polymer chain in a supercooled glass-forming liquid at different amount of supercooling in order to understand how the dynamics of supercooled liquids influence the collapse behavior of the polymer. Our systematic computer simulation studies find that apart from long time relaxation processes (α relaxation), short time dynamics of the supercooled liquid, known as β relaxation plays very important role in controlling the stability of the model polymer. These observations are in stark contrast with the common belief that only long time relaxation processes are the sole players (vitrification hypothesis). We also show that anti-plasticizing effect found in this context can be rationalized using the β-relaxation process. We believe that our results will lead to understand the primary factors in protein stabilization in the context of bio-preservation.