Relationship between surface coverage and end group functionality of molecularly thin perfluoropolyether films

摘要

The relationship between surface coverage and film thickness for perfluoropolyether (PFPE) films with different functional end groups was investigated by measuring the dispersive surface energy. It was found that the strength of end group functionality played an important role in the surface coverage; i.e., PFPE with the stronger end group functionality has the smaller surface coverage. Molecular dynamics simulations with a bead-spring model were employed to investigate the conformation of PFPE films, where the anisotropic radii of gyration were analyzed as a function of the strength of end group functionality. It was found that PFPE became flatter if the strength of end group functionality decreased, which, in turn, increased the surface coverage.