Transition metal complex-based grafted

Figure 12. Schematic of transition metal complex-based grafted copolymer network.

Eisenberg and coworkers have employed acid-base interactions to improve the miscibility of a number of polymer-polymer pairs. Miscible blends were prepared using acid-base interactions, e.g., with SPS (acid derivative) and poly (ethylacrylate-co-4-vinylpyrldine) (91), sulfonated polyisoprene and poly (styrene-co-4-vinylpyridine) (92), and using ion-dipole interactions, e.g., poly (styrene-co-llthium methacrylate) and poly (ethylene oxide) (93). Similarly, Weiss et al. (94) prepared miscible blends of SPS(acid) and amino-terminated poly (alkylene oxide). In addition to miscibility improvements, the interactions between two functionalized polymers offers the possibility for achieving unique molecular architecture with a polymer blend. Sen and Weiss describe the preparation of graft-copolymers by transition metal complexation of two functionalized polymers in another chapter. 

This chapter begins with a general description of the several strategies to het-erogenize transition-metal complexes onto solid supports, with a special emphasis on those methodologies that have been used for complex grafting onto carbon materials. It will include sections that will focus on the various transition-metal complexes that have been immobilized onto several carbon materials activated carbons, black carbons, carbons xerogels, and carbon nanotubes the specific catalytic reactions with these carbon-based systems are also discussed in some detail. 

Due to the nature of carbon materials, the presentation of representative methods for surface derivatization will follow an approach different from that described in the preceding section, which is based on the spatial target site where physical-chemical modification can take place (1) immobilization performed at edges and/or ends and defects of graphitic sheets, (2) immobilization onto the graphene sheets, and (3) exclusively for CNTs we present some examples of endohedral encapsulation of metal complexes. For the first two cases, covalent bonding and noncovalent interactions can occur directly between the transition metal complex and carbon supports or via spacers grafted to the carbon surface. 

Therefore, as Mn2(CO)io was never employed in polymerizations of main chain fluorinated monomers, or with inactivated alkyl halides or with perfluoroalkyl iodides, we decided to assess its scope and limitations as photo-coinitiator and to demonstrate that such LjjMt-MtLjj photolyzable transition metal complexes afford the initiation of VDF polymerization directly from a variety of regular and (per)fluorinated alkyl halides (Cl, Br, I) even at rt, thus opening up novel synthetic avenues for the photome-diated synthesis of block and graft copolymers based on FMs. Second, we also set to kinetically explore such polymerization and investigate the possibility of Mn2(CO)io-mediated IDT-VDF-CRP. Third, we aimed to demonstrate the first examples of the synthesis of well-defined PVDF-block copolymers. 

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