A close look at the conformational transitions of a helical polymer in its response to environmental stimuli

Abstract

We present a study of the conformational transitions of a helical polymer by using coarse-grained molecular dynamics simulations. With focus on the variation of the dihedral angles, we are able to obtain the monomer-level details of the response of the polymer chain to environmental stimuli (e.g., temperature variation and mechanical forces). Specifically, during the thermo-induced helix–coil transition, all the helices break synchronously. On the contrary, the force-induced helix breaking always starts from the termini, and then the chain behaviors become divergent and temperature dependent. Particularly, at intermediate temperatures, we find that our polymer chain can adopt an asymmetrical half-trans conformation during the stretching procedures, although the chain itself has quite uniform and homogeneous composition.