Two-dimensional (2D) nanomaterials have received increasing interest for many applications such as biomedicine and nanotechnology. Here, we report a facile strategy to prepare highly flexible 2D crystalline nanosheets with only ∼6 nm thickness from poly­(ethylene glycol)-block-poly­(N-octylglycine) (PEG-b-PNOG) diblock copolymer in high yield. To our best knowledge, this is the first report of free-floating, 2D extended nanosheets from polypeptoid-based block copolymers. The faceted nanostructures are achieved from hierarchical self-assembly through a sphere-to-cylinder-to-nanosheet transition pathway. The preliminary assembled spheres can behave like a fundamental packing motif to spontaneously stack into a 2D lattice via an intermediate cylinder structure, driven by crystallization of PNOG domains. The nanosheet formation process follows theoretical model for morphology development of crystalline block copolymers in selective solvents. Particularly remarkable is that we obtained the hierarchical nanostructure from synthetic block copolymers through a multiple-step strategy mimetic to protein crystallization. This is fairly distinct from the previously reported crystalline nanosheets. The ability to efficiently create 2D crystals from synthetic polymers by spontaneous assembly will enable new generations of bioinspired nanomaterials for a variety of potential applications in biomedicine and nanotechnology.

Hierarchical nanomaterials have received increasing interest for many applications. Here, we report a facile programmable strategy based on an embedded segmental crystallinity design to prepare unprecedented supramolecular planar nanobrush-like structures composed of two distinct molecular packing motifs, by the self-assembly of one particular diblock copolymer poly(ethylene glycol)-block-poly(N-octylglycine) in a one-pot preparation. We demonstrate that the superstructures result from the temperature-controlled hierarchical self-assembly of preformed spherical micelles by optimizing the crystallization−solvophobicity balance. Particularly remarkable is that these micelles first assemble into linear arrays at elevated temperatures, which, upon cooling, subsequently template further lateral, crystallization-driven assembly in a living manner. Addition of the diblock copolymer chains to the growing nanostructure occurs via a loosely organized micellar intermediate state, which undergoes an unfolding transition to the final crystalline state in the nanobrush. This assembly mechanism is distinct from previous crystallization-driven approaches which occur via unimer addition, and is more akin to protein crystallization. Interestingly, nanobrush formation is conserved over a variety of preparation pathways. The precise control ability over the superstructure, combined with the excellent biocompatibility of polypeptoids, offers great potential for nanomaterials inaccessible previously for a broad range of advanced applications.

It has long been demonstrated the gecko‐inspired micropillar array with T‐shape tips possesses the best adhesion performance of a given material. The further enhancement of the adhesion performances of T‐shape micropillars can offer redundant adhesion to compensate for the inevitable improper contacts. Here, the array of T‐shape polydimethylsiloxane (PDMS) micropillars is incorporated with gradient dispersed calcium carbonate nanoparticles in the micropillar stalk, termed as T‐shape gradient micropillars (TG), possessing the modulus gradient with stiff tip and soft root. The gradient modulus in TG facilitates the contact formation and regulates the stress at the detaching interface, resulting in a 4.6 times adhesion and 2.4 times friction as compared with the pure PDMS T‐shape micropillar arrays. The study here provides a new design strategy for the super‐strong structured dry adhesives.

Stimuli-responsive polymers have received increasing interest for a variety of applications. Here, we report a series of unique charge-determined thermoresponsive polypeptoids synthesized by a combination of ring-opening polymerization and click chemistry. The LCST-type and UCST-type behavior is mainly dominated by the charge state on the side chain. Further, the phase transition temperature highly depends on the degree of polymerization, the side-chain architecture, the pH value, and so on. The obtained polypeptoid solutions exhibit good stability against temperature and salt concentration. To our knowledge, this report presents the first charge-determined LCST/UCST-type polymer from identical homopolymer backbone that displays a wide range of tunable cloudy points in aqueous media. We propose the hydrogen-bonding interaction plays a critical part on the solution behavior. These features make polypeptoids ideal candidates for highly designable stimuli-responsive polymeric materials.