Theory of Polydisperse Inhomogeneous Polymers

A formalism is presented for incorporating realistic molecular weight distributions into field theory models of inhomogeneous polymeric fluids. The method is illustrated in the context of an equilibrium interface between coexisting phases of molten polydisperse A and B homopolymers. We solve the model field theory in the self-consistent mean-field approximation and analyze the structure of the interface for the special case of a Schulz molecular weight distribution. The formalism is general, however, and can be used even beyond the mean-field approximation to assess polydispersity effects in a wide variety of inhomogeneous polymers, such as block and graft copolymers and their alloys.