Frustration in block copolymer assemblies

Frustration is a central concept to understand the self-assembly of block copolymers. At the molecular scale, frustration occurs because the different blocks tend to phase separate whereas the chain connectivity prevents a macroscopic phase separation. At the mesoscopic scale, frustration occurs due to the competition between the tendency for the polymeric domains to maintain a uniform shape and the need to fill the space. Furthermore, frustration could occur due to the topology of multiblock copolymers. Novel ordered morpholgies emerge in orded to alleviate these frustrations. We have carried out extensive theoretical studies on the formation of complex ordered phases from block copolymers. The recent theoretical results provide a good understanding of the origin of various frustrations in block copolymer assemblies. Furthermore, the studies have demonstrated that designed block copolymers, either in the form of multiblock copolymers with different architectures or block copolymer blends, could be utilized to tailor frustrations occurring in block copolymer systems.