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Pittsburgh, PA, United States

Tsarevsky N.V.,ATRP Solutions
Journal of Polymer Science, Part A: Polymer Chemistry | Year: 2010

Polystyrene was directly azidated in 1,2-dichloro-ethane or chlorobenzene using a combination of trimethylsilyl azide and a hypervalent iodine (III) compound, (diacetoxyiodo)-benzene. 2D NMR HMBC experiments indicated that the azide groups were attached to the polymer backbone and also possibly to the aromatic pendant groups. The amount of introduced azide groups was estimated by semi-quantitative IR spectros-copy and elemental analysis. Approximately 1 in every 11 sty-rene units could be modified by using a ratio of hypervalent iodine compound to trimethylsilyl azide to styrene units of 1:2.1:1 at 0 °C for 4 h followed by heating to 50 °C for 2 h in chlorobenzene. The azidated polymers were further used as backbone precursors in the synthesis of polymeric brushes with hydrophilic side chains via a copper-catalyzed click graft-ing-onto reaction with poly(ethylene oxide) monomethyl ether 4-pentynoate. © 2010 Wiley Periodicals, Inc. Source


Patent
ATRP Solutions | Date: 2013-09-25

A polymer composition comprising star macromolecules is provided. Each star macromolecule has a core and five or more arms, wherein the number of arms within a star macromolecule varies across the composition of star molecules. The arms on a star are covalently attached to the core of the star; each arm comprises one or more (co)polymer segments; and at least one arm and/or at least one segment exhibits a different solubility from at least one other arm or one other segment, respectively, in a reference liquid of interest.


A procedure for improved temperature control in controlled radical polymerization processes is disclosed. The procedure is directed at controlling the concentration of the persistent radical in ATRP and NMP polymerizations procedures and the concentration of radicals in a RAFT polymerization process by feeding a reducing agent or radical precursor continuously or intermittently to the reaction medium through one of more ports.


Patent
ATRP Solutions | Date: 2014-02-07

A procedure for improved temperature control in controlled radical polymerization processes is disclosed. The procedure is directed at controlling the concentration of the persistent radical in ATRP and NMP polymerizations procedures and the concentration of radicals in a RAFT polymerization process by feeding a reducing agent or radical precursor continuously or intermittently to the reaction medium through one of more ports.


Patent
ATRP Solutions | Date: 2014-02-03

The present invention relates to multi-arm salt-tolerant star macromolecules, and methods of preparing and using the same. In one aspect of the invention, a salt-tolerant star macromolecule is capable of providing salt-tolerance to an aqueous composition.

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