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.

Supramolecular chirality and its complete self‐recovery ability are highly mystical in nature and biological systems, which remains a major challenge today. Herein, we demonstrate that partially cross‐linked azobenzene (Azo) units can be employed as the potential chiral trigger to fully heal the destroyed helical superstructure in achiral nematic polymer system. Combining the self‐assembly of Azo units and terminal hydroxyl groups in polymer side chains allows the vapor‐induced chiral nematic phase and covalent fixation of the superstructure via acetal reaction. The induced helical structure of Azo units can be stored by inter‐chain cross‐linking, even after removal of the chiral source. Most interestingly, the stored chiral information can trigger perfect chiral self‐recovery (CSR) behavior after being destroyed by UV light, heat, and solvents. The results pave a new way for producing novel chiroptical materials with reversible chirality from achiral sources.

The application of selenol‐X chemistry in nucleophilic substitution and Se‐Michael addition reactions for polymer chain end modification is presented. Selenol‐labeled polystyrene can easily react with alkyl halides, methyl methacrylate, methyl acrylate, pentafluorostyrene, etc. The mild conditions make it attractive for the synthesis of macromonomers. The resulting polymers are analyzed and characterized by UV, size‐exclusion chromatography (SEC), NMR, and matrix assisted laser desorption/ionization time of flight mass spectroscopy.

The first example of atom tramsfer radical polymerization using activators generated by electron transfer (AGET ATRP) of styrene in bulk and solution was investigated in the presence of catalytic amounts of NaOH or Fe(OH) 3 , using FeCl 3 3 6H 2 O as the catalyst, (1-bromoethyl)benzene (PEBr) as the initiator, vitamin C (VC) as the reducing agent, and a cheap and commercially available tetrabutylammonium bromide (TBABr) or tetra-n-butylphosphonium bromide (TBPBr) as the ligand. It was found that both the polymerization rate and controllability over molecular weights and molecular weight distributions (∼1.2) of the resultant polymers could be enhanced in the presence of the catalytic amounts of base as compared with those without base. For example, the polymerization rate of bulk AGET ATRP with a molar ratio of2/1.5 using NaOH as the additive was much faster than that without NaOH. The former was 3.5 times the latter. Furthermore, the polymerization of styrene could be successfully carried out even in the conditions when the amount of iron salts, FeCl 3 3 6H 2 O as the catalyst, reduced to ppm level.