Molecular dynamics simulations of polymers with stiff backbones interacting with single-walled carbon nanotubes

Abstract

The goal of this study is to explore the interface between single-walled carbon nanotubes (SWCNTs) and polymer chains with semiflexible and stiff backbones in vacuum via molecular dynamics (MD) simulations, which complements our previous work with flexible backbone polymers. These simulations investigate the structural and dynamical features of interactions with the SWCNT, such as how the polymers prefer to interface with the SWCNT and how the interfacial interaction is affected by the chemical composition and structure of the polymer. The simulations indicate that polymers with stiff and semiflexible backbones tend to wrap around the SWCNT with more distinct conformations than those with flexible backbones. Aromatic moieties along the backbone appear to dictate the adsorption conformation, which is likely due to the preference for optimizing pi-pi interactions, although the presence of bulky aliphatic side chains can hinder those interactions. Moment of inertia plots as a function of time indicate that the adsorption of polymers with stiff backbones tends to be a two-step process, in contrast to flexible backbones.