Molecular Architecture Driven Self-Assembly of Block Copolymers

Block copolymers composed of immiscible polymeric blocks self-assemble to a rich variety of ordered nanostructures that find applications in many technologically important realms. Among different types of block copolymers, linear-bottlebrush-linear (LBBL) triblock copolymers present an emerging platform for creating multifunctional nanostructures. However, little is known about the fundamental mechanism of their self-assembly. We synthesize a series of LBBL polymers with precisely controlled anisotropy of bottlebrush block and weight fraction of the linear block. Characterizing morphology and microphase separation of the self-assembled nanostructures, we find that the molecular anisotropy of bottlebrush is sufficient to drivee LBBL polymers self-assemble to long range ordered nanostructures with exceptionally large domain sizes inaccessible by existing copolymer systems. Our results suggest that the self-assembly of LBBL polymers is driven by their molecular architecture rather than detailed chemistry. Such understanding may enable discovery of polymeric nanostructures with unpreceded properties and multifunction.