Statistical Mechanics of Flexible High Polymers at Surfaces

Abstract

The isotherm corresponding to monolayer adsorption and the equation of state of a monolayer at a liquid interface are derived. As previously, we replace the number of segments per chain actually deposited, by an average value, which is proportional to t^½ (t total number of segments) and depends on chain flexibility. This introduces a considerable simplification. However, a previous overcounting of configurations on the surface is eliminated. This affects primarily the results at low surface coverage and leads to the anticipated limiting laws. The isotherms differ considerably, although not as much as for rigid macromolecules of equal chain length, from the Langmuir type. The change in surface tension in solution as a function of bulk concentration, molecular weight, and solvent power is calculated.