Multiblock chimeras

Research on the synthesis of polypeptide hybrid diblock copolymers began in the mid-1970s (Yamashita et al., 1975). Advances in polymer synthesis, culminating in the development of controlled/living polymerization techniques and click chemistry (Sumerlin and Vogt, 2010), in combination with the living ROP of NCAs, allowed for the preparation not only of simple diblock but also of a wide variety of multiblock Chimeras. In this section we will describe the materials synthesized according to the macroinitiators used for the ROP of the NCAs amino-and transition-metal complexes. 

The variety of the nanostructures could become even richer and more complex in multiblock copolymers, multiblock multicomponent (e.g. terpolymers) or in nonlinear (e.g. miktoarm stars) (Lodge, 2003) chimeras, approaching that found in nature. Therefore, the synthesis of well defined complex chimeras adds another dimension to the suprastructural hierarchy of the block copolymers with potential biomedical applications (Deming, 2007). 

Although, there are many reviews on linear diblock chimeras, only a very few have addressed the synthesis of polypeptide-based materials with different macromolecular architectures (Hadjichristidis et al., 2009 Deming, 2006 Deming, 2000). In this chapter our discussion on the synthesis of well-defined complex chimeras, including linear multiblock co/ terpolymer, as well as nonlinear copolymer chimeras (e.g. star, graft, block-graft, dendritic), will hopefully enrich the current literature on macromolecular chimeras. This chapter will not address the self-assembly of these complex chimeras since this issue is discussed in another chapter of this volume. 

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