Smectic rod-coil melts confined between flat plates: Monolayer-bilayer andparallel-perpendicular transitions

We study theoretically the equilibrium properties of a rod-coil diblock cop olymer melt confined between two flat plates. We assume that the system for ms lamellae in the bulk. The plates may have a preference for either the ro ds or coils. We investigate whether the preferred alignment of the lamellae is parallel or perpendicular to the plates and how the lamellar spacing ch anges compared to the bulk lamellar spacing. We find that this system is mu ch more constrained than the analogous coil-coil system and for certain val ues of the rod-coil interfacial tensions that perpendicular lamellae exist for quite thick. films. For dissimilar bounding plates we find the antisymm etric parallel morphology may exist.