Living Radical Polymerization by the RAFT Process - A Second Update

Abstract

This paper provides a second update to the review of reversible deactivation radical polymerization achieved with thiocarbonylthio compounds (ZC(=S)SR) by a mechanism of reversible addition-fragmentation chain transfer (RAFT) that was published in June 2005 (Aust. J. Chem. 2005, 58, 379-410). The first update was published in November 2006 (Aust. J. Chem. 2006, 59, 669-692). This review cites over 500 papers that appeared during the period mid-2006 to mid-2009 covering various aspects of RAFT polymerization ranging from reagent synthesis and properties, kinetics and mechanism of polymerization, novel polymer syntheses and a diverse range of applications. Significant developments have occurred, particularly in the areas of novel RAFT agents, techniques for end-group removal and transformation, the production of micro/nanoparticles and modified surfaces, and biopolymer conjugates both for therapeutic and diagnostic applications.

Living Radical Polymerization by the RAFT Process – A Third Update

“…[19] We also refer to some earlier papers that were not included in that or the earlier reviews. Work cited in the previous reviews [17][18][19] is only mentioned again where it is necessary to put the more recent work in context.…”

“…1 which shows the cumulative citations for our first communication on RAFT with thiocarbonylthio compounds, [15] the first RAFT patent, [16] and our previous reviews in the Australian Journal of Chemistry. [17][18][19] Of course, not all papers on RAFT polymerization cite these sources, nor are all of the papers citing these documents directly relevant to RAFT polymerization. Fig.…”

“…[20][21][22][23][24][25] Reviews devoted to specific areas [15] first patent (&) [16] and their 2005 (J) [17] review on RAFT polymerization and its first (B) [18] and second update (,). [19] Based on a SciFinder search carried out in , 'MADIX polymerization'), for ATRP (') ('ATRP', 'atom transfer radical polymerization', metal-mediated radical polymerization) and for other (r) ('nitroxide-mediated polymerization' and 'living radical polymerization', 'controlled radical polymerization' less those already counted under RAFT or ATRP). 'Papers' (closed symbols) includes journal articles, reviews, books, and letters but not conference abstracts or reports.…”

Conjugation of siRNA with Comb‐Type PEG Enhances Serum Stability and Gene Silencing Efficiency

“…[18][19][20] When compared to the linear PEG with equivalent molecular weights, the comb-like PEG displays greater steric hindrance, thus potentially enhancing biostability and lowering clearance rates of the conjugated biotherapeutics. Moreover, comb-shaped PEG-(meth)acrylate polymers can be prepared by reversible addition fragmentation chain transfer (RAFT) polymerization [21][22][23][24][25] and atom transfer radical polymerization (ATRP) techniques, [26][27][28][29] which offer facile synthetic routes to the generation of polymers with controlled molecular weight, varying macromolecular architectures and defined endgroup functionalities. While control over the molecular weight and macromolecular structure of the conjugated polymer is crucial for improved pharmacokinetic properties of the bioconjugates, the defined end-group functionality enables varying synthetic strategies to be implemented for site-specific PEGylation.…”

Recent developments in metal-catalyzed living radical polymerization

“…[1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17] Besides these metal catalytic systems, there have also been substantial developments in various living radical polymerizations, such as nitroxide-mediated polymerizations, reversible addition fragmentation chain-transfer polymerizations and others, and in all of these, there are characteristic features of the mechanisms and components. [18][19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34] The metal-catalyzed living radical polymerization was originally discovered via evolution of the metal-catalyzed Kharasch or atom transfer radical addition reaction 35 to the chain-growth polymerization of vinyl monomers ( Figure 1). 1 The initiating system generally consists of a transition metal complex in a lower oxidation state and an organic halide, in which the carbon-halogen bond of the halogen compound is activated by the metal catalyst to generate the carbon radical species upon a one-electron oxidation of the metal complex associated with the abstraction of the halogen by the metal species.…”