Living radical polymerization LRP

Living radical polymerization (LRP) with reversible termination generally proceeds as... 

A dense polymer brush is obtained using the grafting from techniques. Surface-initiated polymerization in conjunction with a living polymerization technique is one of the most useful synthetic routes for the precise design and functionalization of the surfaces of various solid materials with well-defined polymers and copolymers. Above all, surface-initiated living radical polymerization (LRP) is particularly promising due to its simplicity and versatility and it has been applied for the synthesis of Au NPs. 

The ratio between the rates of parallel eqs 18 and 19 is an issue of practical importance. Cobalt chelates may be good capping agents in living radical polymerization, LRP.206-207 This requires that eq 19 be reversible and the forward and backward (eq 20) rates be approximately equal. 

On the other hand, a functionality of 1 on each chain end will be related to telechelic compounds (Scheme 1). This includes diols, diamines, and diacides. Of course it also comprises diolefin compounds that usually lead to gels or networks. We can also note that when the G and G functional groups are different at each chain end, the appropriate term becomes heterotelechelic (Table 1). It is also necessary to specify the particular case of macromolecules bearing a well-identified G functionality at one chain end and a thermally reactivated group at the G chain end. These groups can be nitroxides, an iodine atom, xanthate, etc.and are commonly used in living radical polymerizations (LRP). These compounds may be classified as monofunctional oligomers (Table 1). 

Living radical polymerization (LRP) has attracted growing attention as a powerful synthetic tool for well-defined polymers 1,2). The basic concept of LRP is the reversible activation of the dormant species Polymer-X to the propagating radical Polymer (Scheme la) 1-3). A number of activation-deactivation cycles are requisite for good control of chain length distribution. 

The living radical polymerization (LRP) approach was first introduced in the 1980s. LRP is a type of polymerization in which a chain can only propagate and not undergo irreversible termination or chain transfer. Hence, LRP is an ideal system to produce monodisperse polymers of known molecular weights, architectures and compositions. Reversible addition-fragmentation chain transfer polymerization (RAFT), atom transfer radical... 

Surface-initiated living radical polymerization (LRP) has been explored to yield... 

Over the past 15 years, new free radical polymerization techniques have been developed which allow significantly improved control over polymer structure at the molecular level. By using these techniques, customized polymeric materials can be produced which are not possible using conventional methods of the past. These new techniques are typically termed living or controlled free radical polymerization. There is some debate over the semantic use of these terms [2,3], but the term living radical polymerization (LRP) will be used here for simplicity. 

Living radical polymerization (LRP) is developed on the basis of conventional free-radical polymerization (FRP). The main idea behind this development is to overcome intrinsic shortcomings of FRP without sacrificing any of its strengths. These strengths are... 

For a recent review of living radical polymerization (LRP) involving organoteUurium, organostibine, and organobismuthine mediated routes (TERP, SBRP, and BIRP, respectively), see Yamago, S. Chem. Rev. 2009,109, 5051. 

Concentrated Polymer Brush Prepared by SI-LRP 11.2.1 Living Radical Polymerization (LRP)... 

With the great development of living radical polymerization (LRP), one can now easily prepare linear polymers with different monomers and functional chain ends. The past decade has seen a boost in new synthetic strategies for cyclic polymers. Lepoittevin et al. [78] pioneered a new synthetic method for cyclization of PSTY by combining NMRP and esterification. 4-Hydroxyl-2,2,6,6-tetramethyl-pyperidine-l-oxy (HTEMPO) and 4,4 -azobis(4-cyanovaleric acid) were used in a combination, yielding linear PSTY with both hydroxyl and carboxylic acid chain ends. Subsequently, the cyclization reaction was catalyzed by l-methyl-2-chloropyridinium iodide and triethylamine (Scheme 27). Because the esterification reaction is not highly efficient, especially when used in polymer systems, this method was only successful with low molecular weight PSTY (<4 kDa). 

Elfective approaches to obtain living radical polymerization (LRP) are separated by reaction mechanism into two broad categories called reversible termination (RT) and degenerative transfer Both reversible... 

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