Atom transfer radical polymerization materials

Matyjaszewski, K. Miller, P. J. Kickelbick, G. Nakagawa, Y. Diamanti, S. Pacis, C. Organic-Inorganic Hybrid Polymers from Atom Transfer Radical Polymerization and Poly(dimethylsiloxane). In Silicones and Silicone-Modified Materials Clarson, S. J., Fitzgerald, J. J., Owen, M. J., Smith, S. D., Eds. ACS Symposium Series 729 American Chemical Society Washington, DC, 2000 pp 270-283. 

Patten TE, Matyjaszewski K (1998) Atom transfer radical polymerization and the synthesis of polymeric materials. Adv Mater 10 901... 

Triphenylamine derivatives are known to be efficient hole transport materials and are widely used in organic light-emitting devices. Thelakkat et al. reported the synthesis of a 2,2-bipyridine ligand capped with polyfvinyl-triphenylamine) at both ends.97 The polymer chain was synthesized by the atom transfer radical polymerization of 4-bromostyrene using 4,4-bis (chloromethyl)bipyridine as the initiator (Scheme 18). The bromide groups were then replaced by diphenylamine in the presence of palladium catalyst. Polymer 33 was then obtained by the metalation reaction. 

The use of a polymer species as a way to control diffusion to the inside of mesoporous silica was also employed by Lopez and coworkers.67 In this work the researchers polymerized iV-isopropyl acrylamide on mesoporous silica by atom transfer radical polymerization, and took advantage of the changes the polymer experiences upon thermal treatment. The authors discovered that the hybrid material could take up more fluorescein than nonfunctionalized material at temperatures above 45°C. At that temperature the polymer is in a collapsed hydrophobic state and partially covers the negatively charged surface of silica that otherwise repels the negatively charged fluorescein dye. At temperatures below 30°C the polymer exists in a hydrated state in which the chains are expanded. Interestingly, the fluorescein loaded hybrid particles were... 

A disadvantage of traditional acrylamide polymerization reactions is the heterogeneity of the products that result. A radical polymerization method that produces polymers of similar structure but that are much more homogeneous is atom-transfer radical polymerization (ATRP) [155,156]. ATRP has been used to synthesize carbohydrate-substituted polymers with low polydispersities [157,158,159,160,161]. Materials that display sugar residues such as glu-cofuranose [160], glucopyranose [161], and A-acetyl-D-glucosamines [159]. 

Three key conditions must be met to design a uniformly reactive, recoverable, and recyclable polymerization catalyst (1) the synthetic protocol used to make the immobilized catalyst must lead to only one type of active site on the surface, (2) the support material must be able to allow sufficient transport of reactants to and polymer from the active site, and (3) at the end of the reaction, the active site must not be irreversibly changed or decomposed [23]. Research in our lab has thus far sought to investigate these points using the atom transfer radical polymerization (ATRP) of methyl methacrylate as a model reaction. 

The reaction with aryl radicals of this kind has found an interesting application in the direct polymerization of vinylic monomers like styrene, methyl methycrylate (MMA), or hydroxyethyl methacrylate (HEMA) on the diamond. Furthermore, the covalent attachment of an initiator molecule allows for an atom transfer radical polymerization (ATRP) to take place immediately on the diamond surface and results in a covalently bound composite material (Figure 6.41). 

The fifty chapters submitted for publication in the ACS Symposium series could not fit into one volume and therefore we decided to split them into two volumes. In order to balance the size of each volume we did not divide the chapters into volumes related to mechanisms and materials but rather to those related to atom transfer radical polymerization (ATRP) and to other controlled/living radical polymerization methods reversible-addition fragmentation transfer (RAFT) and other degenerative transfer techniques, as well as stable free radical pol5mierizations (SFRP) including nitroxide mediated polymerization (NMP) and organometallic mediated radical polymerization (OMRP). 

The development of controlled radical polymerization (CRP) methods,(1,2) including atom transfer radical polymerization (ATRP),(3-6) nitroxide-mediated radical polymerization,(7) and reversible addition fragmentation chain transfer polymerization,(8,9) has led to the synthesis of an unprecedented number of novel, previously inaccessible polymeric materials. Well-defined polymers, i.e., polymers with predetermined molecular weight, narrow molecular weight distribution, and high degree of chain end functionalization, prepared by... 

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... 

Acrylate copolymers with complex linear or star architectures were prepared and characterized. Precise control over the sequence distribntion and overall composition of these materials was achieved by atom transfer radical polymerization. A strong correlation between the molecular stractme and composition of the copolymers and their thermomechanical behavior was foimd. This provides a new way for creating advanced materials with tailored properties. 

Controlled Radical Polymerization (CRP) is the most recently developed polymerization technology for the preparation of well defined functional materials. Three recently developed CRP processes are based upon forming a dynamic equilibrium between active and dormant species that provides a slower more controlled chain growth than conventional radical polymerization. Nitroxide Mediated Polymerization (NMP), Atom Transfer Radical Polymerization (ATRP) and Reversible Addition Fragmentation Transfer (RAFT) have been developed, and improved, over the past two decades, to provide control over radical polymerization processes. This chapter discusses the patents issued on ATRP initiation procedures, new functional materials prepared by CRP, and discusses recent improvements in all three CRP processes. However the ultimate measure of success for any CRP system is the preparation of conunercially viable products using acceptable economical manufacturing procedures. 

The formation of living polymer obeys a completely different mechanism than faced in radial polymerization. With living polymers, highly uniform materials can be synthesized. Living polymerization includes not only anionic polymerization but also atom transfer radical polymerization, living controlled free radical polymerization. 

Matyjaszewski, K., Tsarevsky, N.V., 2009. Nanostructured functional materials prepared by atom transfer radical polymerization. Nat. Chem. 1 (4), 276-288. 

Tsarevsky, N.V. Matyjaszewski, K. Combining atom transfer radical polymerization and disulfide/thiol redox chemistry A route to well-defined (bio)degradable polymeric materials. Macromolecules 2005,38 (8), 3087-3092. 

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