Dissipative particle dynamics parameterization and simulations to predict negative volume excess and structure of PEG and water mixtures

We report the results of dissipative particle dynamics (DPD) parameterization and simulations of a mixture of hydrophilic polymer, PEG 400, and water which are known to exhibit negative volume excess property upon mixing. The addition of a Morse potential to the conventional DPD potential mimics the hydrogen bond attraction, where the parameterization takes the internal chemistry of the beads into account. The results indicate that the mixing of PEG and water are maintained by the influence of hydrogen bonds, and the mesoscopic structure is characterized by the trade-off of enthalpic and entropic effects. (C) 2017 Elsevier B.V. All rights reserved.