Soft Confined Assembly of Polymer-Tethered Inorganic Nanoparticles in Cylindrical Micelles

Abstract

Cylindrical block copolymer (BCP) micelles could be considered as two-dimensional (2D) soft confined space for assembly of inorganic nanoparticles (NPs). However, the deformable boundary of the micelles and the complex interaction between BCP and NPs resulted in a complex nanocomposite system, where cylindrical assemblies would easily deform with increasing NP content, and the NPs would usually distribute randomly in the micelles. Nowadays, it is desirable to maintain the cylindrical structures with high NP content and tailor the packing style of the NPs inside the cylinders. Here, we report the confined assembly of polystyrene (PS)-tethered gold NPs in cylindrical supramolecular micelles, which are made of polystyrene-b-poly(4-vinylpyridine) (PS-b-P4VP) and 3-n-pentadecylphenol (PDP) by hydrogen bonding. By tuning the PDP content to balance the volume ratio of the PS and P4VP(PDP) domains, the cylindrical morphology of the hybrid micelles was maintained and high NP loading efficiency was achieved. The size ratio of NPs and the PS block was revealed as a key to achieve orderly arrangement of NPs. Furthermore, one-dimensional (1D) hybrid micelles with different aligned structures of NPs in the cores were obtained by varying confinement strength. These findings provide new insights for understanding the soft confined-assembly behavior of NPs and a robust route to prepare hybrid cylindrical micelles with novel structures. © 2020 American Chemical Society.