Nanoparticle anisotropy induces sphere-to-cylinder phase transition in block copolymer melts

Block copolymer nanocomposites including anisotropic nanoparticles have been previously found to co-assemble into complex structures with nanoparticle alignment. Anisotropic nanoparticles with large aspect ratios are found to modify the morphology of block copolymers at modest concentrations, inducing a sphere-to-cylinder phase transition by breaking the local symmetry in the vicinity of a solid particle. This transition takes place over a wide range of NP lengths comparable with the BCP spacing. Controlling the orientation of uniaxial nanoparticles provides additional control over the global orientation of the block copolymer, as previously reported by experiments.

Automated summary

Block copolymer nanocomposites with anisotropic nanoparticles can form complex structures with aligned nanoparticles. These anisotropic nanoparticles can induce a phase transition from sphere to cylinder by modifying the morphology of the block copolymer. Additionally, controlling the orientation of the nanoparticles can further control the global orientation of the block copolymer.