Structure and dynamics of water confined in a polyamide reverse-osmosis membrane: A molecular-simulation study

Molecular dynamics simulations were carried out to investigate both the structural and dynamical properties of water trapped inside a highly cross-linked polyamide RO membrane. The heterogeneous structure of the membrane was characterized through local water density and cavity size distributions. Interactions between water molecules and the polyamide membrane were investigated. Water structure and dynamics were explored and correlated with the heterogeneous distribution of the free volumes inside the membrane.