Surface Dynamic Elasticity of Poly(ethylene oxide) Monolayers on a Water Surface

The methods of transverse and longitudinal surface waves and of oscillating barrier were used to measure a surface dynamic elasticity of poly(ethylene oxide) films spread on aqueous substrate within the frequency range of 0.001–520 Hz. Unlike the adsorption films, the main relaxation processes in the spread poly(ethylene oxide) films are observed at higher frequencies. A comparison of static and dynamic values of the surface elasticity shows that the surface film at surface polymer concentrations higher than 0.4 mg/m2 cannot be considered already as purely two-dimensional film. It was found that the surface tension (surface pressure) can be insufficiently sensitive to conformational transformations in the surface polymer films.