The surface segregation of polymer chains in melts due to molecular weight effects has important consequences in determining the mechanical resilience of composite materials. It is thus suggested that the surface behavior of apparently simple blends such as isotopic mixtures are more complicated than thought before. In the second case they considered the surface behavior of a binary blend, in which all segments of one chain interact identically with the surface, while the end moieties of the second species have energetic interactions with the surface that are different from the central beads. Their preliminary experiments suggest, in agreement with theory, that the appropriate tailoring of these end-moieties will dictate which component will partition to a substrate interface. Experimentally, they propose to conduct more detailed experiments on these systems primarily through the use of a new technique, neutron reflectivity, to obtain a better understanding of the physics in these interfacial situations. They have shown that mean-field lattice calculations cannot enumerate the behavior of isotopic polymers and therefore propose to conduct off-lattice Monte Carlo simulations on these systems to delineate their behavior.
