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Electron-deficient borinic acid monomers and corresponding polymers were synthesized with different substituents via a one-pot reaction of Grignard reagents with trimethoxyborane and reversible addition-fragmentation chain transfer polymerization, respectively. Further investigations of substituent effects of borinic acid polymers (PBAs) were carried out, indicating that the thermoresponsive properties of PBAs benefit from the increase of steric hindrance of PBA substituent, while the binding affinity of PBAs with Alizarin Red S, 8-hydroxyquinoline (HQ), and fluoride ion decreases with the increase of steric hindrance of substituent. Attributed to the strong dative N → B bond and the strongly luminescent boron quinolate, the application of phenyl PBA for fluorescence detection of HQ is realized with high sensitivity at the ppm level. These results therefore confirm that borinic acid-containing polymer is a new type of stimuli-responsive polymer in the field of thermoresponsiveness over a wide temperature range and chemical sensor for diol and electron-rich compounds. [ABSTRACT FROM AUTHOR]

The atom transfer radical dispersion polymerization of 4-vinylpyridine (4VP) in an ethanol/H2O mixture displayed two stages of polymerization; the first stage is the formation of a diblock copolymer with the polymerization rate of 1.21 mol·L-1·h-1before 1 h of polymerization, and the second is the main polymerization in micelles formed from the aggregation of the resultant block copolymers with the polymerization rate of 0.009 mol·L-1·h-1. The 2-bromoisobutyryl-terminated poly(ethylene glycol) methyl ether used in the polymerization acts as both a stabilizer and an initiator. The stable micelles with functional core were synthesized by a one-pot strategy via atom transfer radical dispersion copolymerization (ATRDCP) of 4VP and N,N‘-methylenebisacrylamide (MBA) in an ethanol/H2O solution for the first time. In the initial stage of polymerization, 4VP and MBA were copolymerized to form a block copolymer, PEG-b-(4VP-co-MBA), with pendent unreacted vinyl groups, and after phase separation at a critical chain length of P4VP-co-PMBA, the cross-linking reaction and polymerization occurred at the same time, resulting in cross-linked micelles. The volume ratio of ethanol/H2O had a big influence on the ATRDCP. An increase in the relative amount of ethanol in the solvent mixture will increase the solubility of P4VP in the polymerization system, the phase separation will be postponed, and the critical chain length of 4VP blocks at the phase separation becomes longer. As a result, the particles size and the 4VP content in the resultant micelles increase. The Au/polymer composite nanoparticles were successfully prepared by complexation of P4VP with HAuCl4and following reduction with NaBH4. [ABSTRACT FROM AUTHOR]

A facile strategy for control of the polymer topologies can be achieved simply by tuning the feed molar ratio of catalyst to transfer agent in the controlled radical polymerization. [ABSTRACT FROM AUTHOR]

Pyrene molecules containing NBN-doped polycyclic aromatic hydrocarbons (PAHs) have been synthesized by a simple and efficient intermolecular dehydration reaction between 1-pyrenylboronic acid and aromatic diamine. Pyrene-B (o-phenylenediamine) with a five-membered NBN ring and pyrene-B (1,8-diaminonaphthalene) with a six-membered NBN ring show differing luminescence. Pyrene-B (o-phenylenediamine) shows concentration-dependent luminescence and enhanced emission after grinding at solid state. Pyrene-B (1,8-diaminonaphthalene) exhibits a turn-on type luminescence upon fluoride ion addition at lower concentration, as well as concentration-dependent stability. Further potential applications of Pyrene-B (o-phenylenediamine) on artificial light-harvesting film were demonstrated by using commercial NiR dye as acceptor. [ABSTRACT FROM AUTHOR]