Influence of molecular structure on lubrication of aqueous triblock copolymer lubricants between rutile surfaces: An MD approach

The influence of molecular structure on adsorption and lubrication of aqueous triblock copolymer on TiO2surfaces has been investigated using a realistic MD model. Reference data obtained from DFT calculations have been employed to develop an interaction potential between the copolymer and TiO2surface. The results show that R Pluronics form an anchor-buoy-anchor structure absorbed on TiO2surface and L Pluronic for buoy-anchor-buoy structure. The shear of tribo-system influences slightly on the orientation of copolymers and non-slip behavior has been observed at solid-fluid interfaces due to the strong adhesion strength of copolymer on rutile surface. The shear viscosity increases with copolymer concentration and molecular chain length. L Pluronic has a lower shear stress than the R ones.