| 초록 |
The order-to-disorder transitions (ODT) and Lifshitz behaviors for ring multiblock (AB)n copolymer with periodicity in their sequences are investigated by the Random Phase Approximation methods (RPA). Comparison is made with the correspondingly linear multiblock copolymers. The RPA calculations are qualitatively consistent with the experimental and theoretical results. The monomer sequence of the copolymer chain varies from a step gradient to a full linear gradient. With increasing the periodicity in the ring multiblock gradient copolymer, the ODT line moves downward for ring multiblock copolymers while they move upward for the linear multiblock copolymers. Changing the topologies from linear into ring increases the miscibility and decreases the domain sizes of microphases. |
