General Aspects of Transition Metal-Catalyzed Polymerization in Aqueous Systems

General Aspects of Transition Metal-Catalyzed Polymerization in Aqueous Systems 

The previous section demonstrated the utility of polymerization reactions in aqueous systems. Carrying out transition metal-catalyzed polymerizations in aqueous systems is of great interest as they can afford a variety of new materials not accessible by established free radical techniques. Thus, various monomers subject to catalytic polymerization can not be polymerized by free radical polymerization, and catalytic polymerization also offers access to other polymer microstructures. 

In addition, control of free radical polymerization (e.g. with respect to molecular weight distributions) can be brought about by metal complexes. 

The majority of reactions involve organometallic species, most often metal-alkyl complexes. While such complexes are generally considered to be prone to hydrolysis [Eq. (1)], examples of quite stable alkyl complexes of late transition metals 

Also for species not involving metal-carbon bonds, such as in ATRP, possible 

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