Monolayers of Diblock Copolymer at the Air-Water Interface: The Attractive Monomer-Surface Case

摘要

We have studied both experimentally and theoretically the surface pressureisotherms of copolymers of polystyrene-polyethyleneoxide (PS-PEO) at theair-water interface. The SCMF (single chain mean-field) theory provides a verygood agreement with the experiments for the entire range of surface densitiesand shows that the adsorption energy per PEO monomer at the air-water interfaceis about one $k_B T$. In addition, the chain density profile has beencalculated for a variety of surface densities, from the dilute to the verydense ones. The SCMF approach has been complemented by a mean-field approach inthe low density regime, where the PEO chains act as a two-dimensional layer.Both theoretical calculations agree with the experiments in this region.