General rightsThis document is made available in accordance with publisher policies. Please cite only the published version using the reference above.

The creation of synthetic 2D materials represents an attractive challenge that is ultimately driven by their prospective uses in, for example, electronics, biomedicine, catalysis, sensing, and as membranes for separation and filtration. This Review illustrates some recent advances in this diverse field with a focus on covalent and non-covalent 2D polymers and frameworks, and self-assembled 2D materials derived from nanoparticles, homopolymers, and block copolymers.

Cylindrical block copolymer micelles have shown considerable promise in various fields of biomedical research. However, unlike spherical micelles and vesicles, control over their dimensions in biologically-relevant solvents has posed a key challenge that potentially limits in depth studies and their optimisation for applications. Here, we report the preparation of cylindrical micelles of length in the wide range of 40 nm -1.10 µm in aqueous media with narrow length distributions (length polydispersities < 1.10). In our approach, an amphiphilic linear-brush block copolymer, with high potential for functionalization, was synthesized based on poly(ferrocenyldimethylsilane)-b-poly(allyl glycidyl ether) (PFS-b-PAGE) decorated with triethylene glycol (TEG), abbreviated as PFS-b-(PEO-g-TEG). PFS-b-(PEO-g-TEG) cylindrical micelles of controlled length with low polydispersities were prepared in N,N-dimethylformamide using small seed initiators via living crystallization-driven self-assembly. Successful dispersion of these micelles into aqueous media was achieved by dialysis against deionized water. Furthermore, B-A-B amphiphilic triblock comicelles with PFS-b-poly(2-vinylpyridine) (P2VP) as hydrophobic "B" blocks and hydrophilic PFS-b-(PEO-g-TEG) "A" segments were prepared and their hierarchical self-assembly in aqueous media studied. It was found that superstructures formed depend on the length of the hydrophobic blocks. Quaternization of P2VP was shown to cause the disassembly of the superstructures, resulting in the first examples of water-soluble cylindrical multi-block comicelles. We also demonstrate the ability of the triblock comicelles with quaternized terminal segments to complex DNA and, thus, to potentially function as gene vectors.

The formation of high aspect ratio supramolecular polymeric nanofibers from square-planar platinum(II) complexes through Pt···Pt and π-π stacking interactions has been achieved with a small width (<15 nm), tunable length, and relatively narrow length distributions up to ca. 400 nm under conditions of kinetic control using small seed fibers as initiators.

General rightsThis document is made available in accordance with publisher policies. Please cite only the published version using the reference above. ABSTRACT: Rectangular platelets formed by the self-assembly of block copolymers in selective solvents are of interest for a range of applications. Recently we showed that the seeded growth of crystallizable blends of a block copolymer and homopolymer yields well-defined, low dispersity examples of these two-dimensional (2D) structures. The key feature was the use of the same crystallizable polymer segment in the seed and blend components to enable an efficient homoepitaxial growth process. Herein we demonstrate that this 2D crystallization-driven self-assembly approach can be extended to heteropitaxial growth by the use of different crystallizable polymers with compatible crystal structures. This allows the formation of well-defined "patchy" rectangular platelets and platelet block comicelles with different core chemistries. The use of scanning transmission electron microscopy-energy-dispersive X-ray spectroscopy provided key information on the spatial location of the components in the resulting assemblies and thereby valuable insight into the 2D heteroepitaxial growth process.