Tricontinuous Cubic Structures inABC/A/CCopolymer and Homopolymer Blends

Using the Monte Carlo lattice-simulation technique, we present numerical evidence of the formation of gyroid and nongyroid tricontinuous cubic phases in high polymeric systems of $ABC/A/C$ triblock copolymer and homopolymer blends. By increasing the volume fraction of homopolymer, a remarkable phase sequence $G$ (gyroid) $\to$ $D$ (diamond) $\to$ $P$ (primitive) is observed, which is common to certain surfactant systems. Our results indicate that the $ABC$ triblock copolymer system with blending homopolymers may be a zoo of cubic phases, suitable for comparative studies of these phases.