Novel synthesis of branched polystyrenes by quasi‐living radical copolymerization using photofunctional inimer

Abstract

Branched polystyrenes were prepared by quasi‐living radical copolymerization of N,N‐diethylaminodithiocarbamoylmethylstyrene (inimer: DTCS) with styrene under UV irradiation. DTCS monomers play an important role in this copolymerization system as an inimer capable of initiating living radical polymerization of the vinyl group. Two monomers (DTCS and styrene) showed equal reactivity toward both propagating species, and the copolymer composition was the same as the comonomer feed. This result means that both the branching and chain length of the hyperbranched molecules can be controlled statistically by the feed monomer ratios. The compact nature of the branched macromolecules is demonstrated by viscosity measurements compared to the linear analogues.© 2001 Society of Chemical Industry

Solution properties of hyperbranched polymers and synthetic application for amphiphilic star‐hyperbranched copolymers by grafting from hyperbranched macroinitiator

“…Photopolymerizations of DTCS in benzene solution were carried out by irradiation with UV light in a sealed glass ampoule under high vacuum at 20 °C (250 W high‐pressure mercury lamp, Ushio Denki UI 250D; irradiation distance 20 cm) 9. Branched PSs were also prepared by living radical copolymerization of DTCS with styrene with UV irradiation, varying the feed comonomer ratios 11. The precipitation fractionation of each hyperbranched PS was carried out with a benzene–methanol system, because the hyperbranched PSs exhibited a broad molecular weight distribution.…”

“…The latter species add monomer before recombining with nitroxide to give a new alkoxyamine. Branched PSs have also been prepared by living radical copolymerization of DTCS and styrene 11. Two monomers (DTCS and styrene) showed equal reactivity towards both propagating species, and the copolymer composition was the same as the comonomer composition.…”

Structural and conformational properties of hyperbranched copolymers based on perfluorinated germanium hydrides

“…Most publications devoted to the solution behavior of HBPs deal with polymers with flexible chain spac ers [10][11][12][13][14][15][16][17][18][19][20], whereas the data on the behavior of poly mers with rigid chains between branching points is scarce. In this study, the hydrodynamic and conforma tional properties of branched copolymers based on perfluorinated germanium hydrides of various struc tures (co PPGs) are considered.…”

“Green” Atom Transfer Radical Polymerization: From Process Design to Preparation of Well-Defined Environmentally Friendly Polymeric Materials

“…Other CRP techniques employing inimers have also been used. [470][471][472][473][474][475] Another useful approach to branched polymers is the copolymerization of monomers containing one double bond with a cross-linking agent (a divinyl compound, dimethacrylate, etc.) wherein the latter is used at low concentration in order to prevent the formation of a gel.…”