Water permeation through monolayers of polymerised surfactants

Surface pressure as a function of area per polymer repeat unit (π-A) isotherms and resistances to water evaporation (r) have been measured for monolayers of poly(octadecyl methacrylate), poly(octadecyl acrylate) and poly(vinyl stearate). For each polymer, there were several samples of different molar mass and polydispersity. All samples were polymerised before spreading at the air-water interface. The Langmuir-Schaefer method was employed to measure evaporation resistances. The π-A and r data for the polymerised surfactants suggest that, at least in the weight average molar mass range of 60-900 kg mol and polydispersity range of 2-9, monolayer properties do not depend markedly on molar mass or polydispersity. The evaporation resistances of the polymerised surfactants (