The hydrodynamics of polymer solutions is modeled using a newly developed, thermodynamically consistent, generalized bracket formulation. This continuum thermodynamic development clarifies the connection between the physical assumptions introduced in previous models by Helfand and Fredrickson, Onuki, Doi, and Milner and the final governing equations. A quantitative description of the coupling between elastic stresses and concentration changes as well as the modeling of interphases is provided. The resulting equations describe the same phenomenology as the previous works; however, they are quantitatively different.

• Received 24 February 1992

DOI:https://doi.org/10.1103/PhysRevLett.69.273