Transition Paths of Ordered Phases in a Diblock Copolymer under Cylindrical Confinement

• DOI: 10.1021/acs.macromol.3c01960
• Publication Date: 2023-12-13T19:40:31Z
• Authors: Junying Yang; Qingshu Dong; Li Peng; Xianbo Huang; Weihua Li
• Keywords: Nanopore; Merge (version control); Confined space

The kinetic evolution of ordered phases, i.e., single-cylinder (C1), stacked disks (Dk), and single-helix (H1), formed by a cylinder-forming AB diblock copolymer melt under the confinement nanopores is investigated using self-consistent field theory (SCFT) in conjunction with string method. For C1 → H1, nucleation piece H1 rate-determining step, so heterogeneous process preferred. Dk transition confined small nanopore, phase tends to break sequentially, forming one one. first barrier for breaking straight cylinder largest barrier, which implies that this topological change morphology rate-limiting process. During Dk, it could be easy system fall into stuck structure tilted due mismatching period. case all toroids, then these toroids helical pieces. Exhaustive enumeration indicates there exist several paths close occurrence probabilities. Sometimes possible toroid merge together, but connection two adjacent pieces Our work helpful deepening understanding mechanism phases block copolymers nanopores.