Large-Scale Synthesis of Janus Nanorods by Electrostatics-Mediated Intramolecular Cross-Linking of Polymeric Bottlebrushes

Nanorods are promising to construct functional superstructures. The currently used nanorods are essentially symmetric, with the same materials at the ends. Theoretical prediction indicates that asymmetric Janus nanorods with varied materials at the ends are advantageous in the synthesis of diversified functional self-assembled materials. Herein, we propose a novel method of electrostatics-mediated intramolecular cross-linking of Janus polymer bottlebrushes to synthesize large-scale asymmetric Janus nanorods at an unprecedentedly high concentration of 300 mg/mL. Compositions of both the nanorod body and ends are broadly tunable in an orthogonal mode to endow the nanorod functional groups for self-assembly, which could be visualized under a STED microscope upon dyeing. The sample amino acid analogous Janus nanorods are achieved by the orthogonal hydrolysis and click reaction at the opposite ends, serving as building blocks to self-organize into superstructures from linear wires, branches, and networks that are highly dependent on the valence states.