SELF-CONSISTENT-FIELD THEORY OF BLOCK-COPOLYMERS WITH CONFORMATIONAL ASYMMETRY

Using self-consistent mean field theory, we have investigated the effects of conformational asymmetry on the phase diagram of diblock copolymers, considering spherical, cylindrical and lamellar microphases. This asymmetry, which reflects the mismatch of the pure component densities and Kuhn statistical lengths for the two blocks, is characterized by a single additional parameter. We calculated one phase diagram for systems with asymmetry corresponding approximately to copolymers such as PS-b-PI or PS-b-PBD, and a second one for a system with high asymmetry. In addition to shifting the microphase boundaries, it opens up direct windows from the disordered phase to the lamellar and cylindrical phases on one side of the phase diagram.