The first example of a novel Azo-linked 2D COF with a hexagonal skeleton, high crystallinity and permanent porosity. The trans-to-cis photoisomerization can lead to the decline of Azo-COF crystallinity but cannot impact the pore size of Azo-COF. The current results will provide a strategy for designing smart COF materials.

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Polymer-encapsulated gold or silver nanoparticles were synthesized and sterically stabilized by a shell layer of poly(4-vinylpyridine) (P4VP) grafted on SiO(2) nanoparticles that acts as a scaffold for the synthesis of hybrid noble metal nanomaterials. The grafting P4VP shell was synthesized via surface reversible addition-fragmentation chain transfer (RAFT) polymerization of 4-vinylpyridine (4VP) using SiO(2)-supported benzyl 9H-carbazole-9-carbodithioate (SiO(2)-BCBD) as the RAFT agent. The covalently tethered P4VP shell can coordinate with various transition metal ions such as Au(3+) or Ag(+) and therefore stabilize the corresponding Au or Ag nanoparticles reduced in situ by sodium borohydride (NaBH(4)) or trisodium citrate. The SiO(2)-supported RAFT agent and the Au or Ag nanoparticles embedded in the P4VP shell layer were characterized by UV-vis spectrophotometer, X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and surface-enhanced Raman spectroscopy (SERS).

Digital polymers with precisely ordered units acting as the coded 0- or 1-bit, are introduced as a promising option for molecular data storage. However, the pursuit of better performance in terms of high storage capacity and useful functions never stops. Herein, we propose a concept of an information-coded 2D digital dendrimer. The divergent growth via thiol-maleimide Michael coupling allows precise arrangements of the 0- and 1-bits in the uniform dendrimers. A protocol for calculating the storage capacity of non-linear binary digital dendrimer is established based on data matrix barcode, generated by the tandem mass spectrometry decoding and encryption. Furthermore, the generated data matrix barcode can be read by a common hand-held device to cater the applications such as item identification, traceability and anticouterfeiting purpose. This work demonstrates the high data storage capacity of a uniform dendrimer and uncovers good opportunities for the digital polymers.

Orthogonal maleimide and thiol deprotections were combined with thiol-maleimide coupling to synthesize discrete oligomers/macromolecules on a gram scale with molecular weights up to 27.4 kDa (128mer, 7.9 g) using an iterative exponential growth strategy with a degree of polymerization (DP) of 2 -1. Using the same chemistry, a "readable" sequence-defined oligomer and a discrete cyclic topology were also created. Furthermore, uniform dendrons were fabricated using sequential growth (DP=2 -1) or double exponential dendrimer growth approaches (DP=22n -1) with significantly accelerated growth rates. A versatile, efficient, and metal-free method for construction of discrete oligomers with tailored structures and a high growth rate would greatly facilitate research into the structure-property relationships of sophisticated polymeric materials.