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A robust method for preparing controlled poly(vinyl ethers) utilizing commercially available reagents under visible light is reported. Pentacarbonylbromomanganese (Mn(CO)5Br), generated from the conventional photolysis of manganese carbonyl and halide abstraction, is considered as a catalyst to oxidize carbon radical to carbenium ion in this polymerization. Polymerization behavior including the effects of solvents and monomers have been investigated. [ABSTRACT FROM AUTHOR]

Polymer molecular weight distribution (MWD) is a key parameter of polymers. Here we present a robust method for controlling polymer MWD in controlled cationic polymerizations. A latent mediator strategy was designed and combined with temporal programming to regenerate mediators at different times during polymerization. Both the breadths and shapes of MWD curves were tuned easily by adjusting an external light source. Bimodal, trimodal, and tetramodal distributions were obtained, and the breadths could be varied from 1.06 to 2.09. Polymers with different MWDs prepared by this method had good chain end fidelity, which was demonstrated with successful chain‐extension experiments. In addition, the introduction of temporal programming with a computer‐controlled single chip for the light source opened an avenue for the use of artificial intelligence in polymer synthesis. [ABSTRACT FROM AUTHOR]

Polymer molecular weight distribution (MWD) is a key parameter of polymers. Here we present a robust method for controlling polymer MWD in controlled cationic polymerizations. A latent mediator strategy was designed and combined with temporal programming to regenerate mediators at different times during polymerization. Both the breadths and shapes of MWD curves were tuned easily by adjusting an external light source. Bimodal, trimodal, and tetramodal distributions were obtained, and the breadths could be varied from 1.06 to 2.09. Polymers with different MWDs prepared by this method had good chain end fidelity, which was demonstrated with successful chain‐extension experiments. In addition, the introduction of temporal programming with a computer‐controlled single chip for the light source opened an avenue for the use of artificial intelligence in polymer synthesis. [ABSTRACT FROM AUTHOR]

[Display omitted] • First microflow cationic polymerization under ambient conditions. • No further purification of all reagents were required. • Well-defined poly(vinyl ether)s can be achieved within 2 min. Living cationic polymerization is a well-established method for preparing polymers with controlled molecular weights and complex architectures, but rigorous polymerization conditions limit its widespread application. Here, we report a facile strategy for simplifying the strict conditions required for traditional living cationic polymerizations of various vinyl ethers including ethyl vinyl ether (EVE), propyl vinyl ether (PVE), butyl vinyl ether (BVE) and isobutyl vinyl ether (IBVE) by utilizing continuous microflow reactors and a weak Lewis acid, zinc chloride (ZnCl 2). Well-defined polymers with controlled molecular weights and narrow molecular weight distributions (<1.20) can be obtained under ambient conditions without monomer purification, temperature control or strictly anhydrous conditions. The living nature of the polymerization was verified by kinetic experiments and successful in situ chain extension. [ABSTRACT FROM AUTHOR]

P,P-Diphenyl phosphinodiselenoic acid benzyl ester was synthesized and used as a mediator for the polymerization of styrene under UV-vis irradiation. Moderately controlled evidence was found: linear polymerization kinetics, linear evolution of molecular weight with monomer conversion, and relatively narrow molecular weight distribution (1.5-2.0). The structure of the obtained polymers was characterized using NMR and oxidative eliminaton. Based on polymerization results, an iniferter mechanism was proposed for the current polymerization system. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012 [ABSTRACT FROM AUTHOR]

Selenide-containing amphiphilic copolymers have shown significant potential for application in drug release systems. Herein, we present a methodology for the design of a reactive oxygen species-responsive amphiphilic diblock selenide-labeled copolymer. This copolymer with controlled molecular weight and narrow molecular weight distribution was prepared by sequential organoselenium-mediated reversible addition fragmentation chain transfer (Se-RAFT) polymerization and selenol-based nucleophilic reaction. Nuclear magnetic resonance (NMR) and matrix-assisted laser desorption/ionization time-to-flight (MALDI-TOF) techniques were used to characterize its structure. Its corresponding nanomicelles successfully formed through self-assembly from the copolymer itself. Such nanomicelles could rapidly disassemble under oxidative conditions due to the fragmentation of the Se–C bond. Therefore, this type of nanomicelle based on selenide-labeled amphiphilic copolymers potentially provides a new platform for drug delivery. [ABSTRACT FROM AUTHOR]