Self-organization of rectangular bipyramidal helical columns by supramolecular orientational memory epitaxially nucleated from a Frank-Kasper σ phase

作者：Virgil Percec, Ning Huang, Qi Xiao, Benjamin E. Partridge, Dipankar Sahoo, Mohammad R. Imam, Mihai Peterca, Robert Graf, H. W. Spieß, Xiangbing Zeng, Goran Ungar · 发表于：Giant · 年份：2021 · DOI：10.1016/j.giant.2021.100084 · 被引用次数：27 · 研究领域：Supramolecular Self-Assembly in Materials、Polymer composites and self-healing、Polydiacetylene-based materials and applications

Programming living and soft complex matter via primary structure and self-organization represents the key methodology employed to design functions in biological and synthetic nanoscience. Memory effects have been used to create commercial technologies including liquid crystal displays and biomedical applications based on shape memory polymers. Supramolecular orientational memory (SOM), induced by an epitaxial nucleation mediated by the close contact spheres of cubic phases, emerged as a pathway to engineer complex nanoscale soft matter of helical columnar hexagonal arrays. SOM preserves the crystallographic directions of close contact supramolecular spheres from the 3D phase upon cooling to the columnar hexagonal periodic array. Despite the diversity of 3D periodic and quasiperiodic nanoarrays of supramolecular dendrimers, including Frank-Kasper and quasicrystal, all examples of SOM to date were mediated by Im3¯m (body-centered cubic, BCC) and Pm3¯n (Frank-Kasper A15) cubic phases. Expanding the scope of SOM to non-cubic arrays is expected to generate additional morphologies that were not yet available by any other methods. Here we demonstrate the SOM of a dendronized triphenylene that self-organizes into helical columnar hexagonal and tetragonal P42/mnm (Frank-Kasper σ) phases. Structural analysis of oriented fibers by X-ray diffraction reveals that helical columnar hexagonal domains self-organize an unusual rectangular bipyramidal morphology upon cooling from the σ phase. T...