Atom transfer radical polymerization methacrylate -based

In 2003, the van Hest group produced elastin-based side-chain polymers [123]. This research was motivated by the demonstration of the occurrence of an inverse temperature transition in a single repeat of VPGVG [124]. A methacrylate-functionalized VPGVG was synthesized and used as a monomer to perform atom transfer radical polymerization (ATRP) to produce homopolymers (Fig. 16b) or... 

The last decades have witnessed the emergence of new living Vcontrolled polymerizations based on radical chemistry [81, 82]. Two main approaches have been investigated the first involves mediation of the free radical process by stable nitroxyl radicals, such as TEMPO while the second relies upon a Kharash-type reaction mediated by metal complexes such as copper(I) bromide ligated with 2,2 -bipyridine. In the latter case, the polymerization is initiated by alkyl halides or arenesulfonyl halides. Nitroxide-based initiators are efficient for styrene and styrene derivatives, while the metal-mediated polymerization system, the so called ATRP (Atom Transfer Radical Polymerization) seems the most robust since it can be successfully applied to the living Vcontrolled polymerization of styrenes, acrylates, methacrylates, acrylonitrile, and isobutene. Significantly, both TEMPO and metal-mediated polymerization systems allow molec-... 

Ruthenium(II)-NHC systems ean be used for atom transfer radical polymerization (ATRP). Generally, similar results as for the analogous phosphine complexes are obtained. For the ATRP of styrene and methyl methacrylate (MMA) [(NHC)2peBr2] was found to rival copper(I)-based systems and to yield poly (MMA) with low polydispersities. Polymerizations based on olefin metathesis that are catalyzed by ruthenium-NHC complexes are discussed separately vide supra). 

The ruthenium indenylidene Schiff base complexes XXVIIIa and XXVIIId, synthesized by Verpoort, were evaluated in atom-transfer radical polymerization of methyl methacrylate. The polymerization was initiated by ethyl 2-bromo-2-methyl-... 

Louie and Grubbs prepared an iron-based catalyst for atom transfer radical polymerization (ATRP) [49]. By heating a solution of Iz Prim and FeX2 (X = Br, Cl), crystals of Fe(Iz Prim)2X2 were obtained. These complexes mediated the homogeneous ATRP of styrene and methyl methacrylate with... 

Thermoresponsive polymers based on oligo(ethylene glycol) acrylates or methacrylates can be easily prepared by atom transfer radical polymerization under straightforward experimental conditions (i.e. in bulk or in ethanol solution and in the presence of commercially available catalysts). Thus, these stimuli-responsive macromolecules can be exploited for preparing a wide range of smart advanced materials such as thermoreversible hydrogels, thermoresponsive block-copolymer micelles and switchable surfaces. Hence, some of the results... 

Huang, J. Cusick, B. Pietrasik, J. Wang, L. Kowalewski, T. Lin, Q. Matyjaszewski, K. Synthesis and in situ atomic force microscopy characterization of temperature-responsive hydrogels based on poly(2-(dimethylamino)ethyl methacrylate) prepared by atom transfer radical polymerization. Langmuir 2007, 23 (1), 241-249. 

ALI Ali, M.M. and Stoever, H.D.H., Well-defined amphiphilic thermosensitive copolymers based on poly(ethylene glycol monomethacrylate) and methyl methacrylate prepared by atom transfer radical polymerization, Macromolecules, 37, 5219, 2004. 

A parallel development was initiated by the first publications from Sawamoto and Matyjaszweski. They reported independently on the transition-metal-catalyzed polymerization of various vinyl monomers (14,15). The technique, which was termed atom transfer radical polymerization (ATRP), uses an activated alkyl halide as initiator, and a transition-metal complex in its lower oxidation state as the catalyst. Similar to the nitroxide-mediated polymerization, ATRP is based on the reversible termination of growing radicals. ATRP was developed as an extension of atom transfer radical addition (ATRA), the so-called Kharasch reaction (16). ATRP turned out to be a versatile technique for the controlled polymerization of styrene derivatives, acrylates, methacrylates, etc. Because of the use of activated alkyl halides as initiators, the introduction of functional endgroups in the polymer chain turned out to be easy (17-22). Although many different transition metals have been used in ATRP, by far the most frequently used metal is copper. Nitrogen-based ligands, eg substituted bipyridines (14), alkyl pyridinimine (Schiff s base) (23), and multidentate tertiary alkyl amines (24), are used to solubilize the metal salt and to adjust its redox potential in order to match the requirements for an ATRP catalyst. In conjunction with copper, the most powerful ligand at present is probably tris[2-(dimethylamino)ethyl)]amine (Mee-TREN) (25). 

Lobb EJ, Ma I, BiUingham NC, Ames SP, Lewis AL. Facile synthesis of well-defined, biocompatible phosphoiylcholine-based methacrylate copolymers via atom transfer radical polymerization at 20°C. J Am Chem Soc 2001 123(32) 7913. ... 

Sha K, Li D, Li Y, Liu X, Wang S, Guan J. Synthesis, characterization, and micellization of an epoxy-based amphiphilic diblock copolymer of e-caprolactone and glycidyl methacrylate by enzymatic ring-opening polymerization and atom transfer radical polymerization. J Polym Sci, Part A Polym Chem 2007 45 5037-49. 

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