MULTIBLOCK COPOLYMERS AT INTERFACES

We consider the configurations and the various regimes when an alterna ting, symmetric, multiblock copolymer made of successive sequences of A and B monomers with equal length Z is at the interface between two i mmiscible solvents that are respectively good for one of the sequences and poor for the other one. We find two semi-dilute regimes, when the copolymers overlap. For monomer concentrations below Gamma*, we find a first range where the thickness of the copolymers is constant and e qual to the radius of a sequence. For concentrations larger than Gamma *, a second regime appears, where the sequences stretch out and adopt a conformation similar to what was reported for grafted polymers. Fin ally at a concentration Gamma(sat), the interface is completely satura ted, and the copolymers form micelles in the bulk: it becomes energeti cally more favourable to have copolymers in the bulk than at interface .