Living polymerization, versatility

Polymerizations of methacrylic monomers in the presence of methacrylic macromonomers under monomer-starved conditions display many of the characteristics of living polymerization (Scheme 9.36). These systems involve RAFT (Section 9.5.2). However, RAFT with appropriate thiocarbonylthio compounds is the most well known process of this class (Section 9.5.3). It is also the most versatile having been shown to be compatible with most monomer types and a very wide range of reaction conditions.382... 

Nyce GW, Glauser T, Connor EF, Mock A, Waymouth RM, Hedrick JL (2003) In situ generation of carbenes a general and versatile platform for organocatalytic living polymerization. J Am Chem Soc 125 3046-3056... 

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. 

Techniques derived from anionic or cationic living polymerization methods have widely been used. They are efficient because of the long lifetime of the active sites. Once polymerization is completed these sites are used for functionalization purposes. Alternately, unsaturated ionic initiators have been used but to a lesser extent because of the requirement involved that the polymerizable groups remain unscathed during the macromonomer formation. The versatile inifer method has also been applied to the synthesis of macromonomers. 

Living polymerizations provide the most versatile synthetic routes for the preparation of a wide variety of well-defined polymer structures. Macromonomers... 

As discussed in Chapter 7, the absence of termination in living polymerization permits the synthesis of unusual and unique block polymers — star- and comb-shaped polymers. Living polymerization can also be employed to introduce a variety of desired functional groups at one or both ends of polymeric chains both in homo- and block polymers. In particular, living polymerization techniques provide the synthetic polymer chemist with a vital and versatile tool to control the architecture of a polymer complicated macromolecules can be synthesized to meet the rigid specification imposed by a scientific or technological demand. 

Living polymerization was discovered in anionic system by Szwarc (see p. 476) in 1950, which, as we shall see in Chapter 8, offers many bene ts including the ability to control molecular weight and polydispersity and to prepare block copolymers and other polymers of complex architecture. Many attempts have then been made to develop a living polymerization process with free-radical mechanism so that it could combine the virtues of living polymerization with versatility and convenience of free-radical polymerization. Considering the enormous importance and application potential of living/controlled radical polymerization techniques, these will be considered in detail in another chapter (Chapter 11) with a state-of-the art discussion on the subject. 

Di J, Sogah DY (2006) Intergallery living polymerization using silicate-anchored photoiniferter. A versatile preparatory method for exfoliated silicate nanocomposites. Macromolecules 39(3) 1020-1028... 

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