Conformational and Dynamic Properties of Poly(ethylene oxide) in BMIM+BF4–: A Microsecond Computer Simulation Study Using ab Initio Force Fields

The behavior of polymers in complex solvents is interesting from a fundamental perspective and of practical importance from the standpoint of polymer processing. There has been recent interest in the conformational and dynamic properties of polymer in room temperature ionic liquids, with conflicting predictions from computations using models with different resolutions and conflicting results of experiments from different groups. In this work, we develop a first-principles, nonpolarizable united atom (UA) force field for a mixture of poly(ethylene oxide) (PEO) in the ionic liquid BMIM + BF 4 – . The UA force field is benchmarked against ab initio calculations, and the PEO atomic charges are parametrized to implicitly capture the polarization contribution to the solvation energy of a single PEO molecule in BMIM + BF 4 – . The UA model allows one to perform multi-microsecond molecular dynam…