Molecular Weight Dependence of Polymer Interfacial Tension and Density Profile

We have calculated the molecular weight dependence of the interfacial tension and the density profile of a phase separated binary polymer mixture. The calculation is done in a mean field approximation, which ignores fluctuation effects, if any. Changes in the composition profile are brought about by two effects. The first is entropic adsorption of chain ends to the interfacial region. The second is the readjustment of the rest of the molecule in such a way as to keep the total polymer density at each point constant.