Controlled polymer synthesis

The past decade has witnessed the explosive development of controlled/living polymerization processes that allow synthesis of macromolecules with precisely controlled architecture, molar mass, and functionality from a wide range of 

FIGURE 3.7 Synthesis of poly(vinyl alcohol) by hydrolysis of poly(vinyl acetate). 

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Sawamoto, M., Prog. Polym. Sci., 16, 111 (1991) Controlled Polymer Synthesis by Cationic Polymerization, Chap. 5 in Cationic Polymerizations Mechanisms, Synthesis, and Applications,... 

Takeuchi D, Watanabe Y, Aida T, Inoue S (1995) Maclomolecules 28 651 Recent reviews (a) Aida T (1994) Prog Polym Sci 19 469 (b) Inoue S, Aida T (1998) Controlled polymer synthesis with metalloporphyrins. In Vogl O, Hatada K (eds) Molecular design of polymeric materials. Dekker, New York, in press (a) Kuroki M, Watanabe T, Aida T, Inoue S (1991) J Am Chem Soc 113 5903 (b) Sugimoto H, Kuroki M, Watanabe T, Kawamura C,Aida T, Inoue S (1993) Macromolecules 26 3403 (c) Sugimoto H,AidaT, Inoue S (1994) Macromolecules 27 3672 (d) Sugimoto H, Kawamura C, Kuroki M, Aida T, Inoue S (1994) Macromolecules 27 2013 (e) Akatsuka M, Aida T, Inoue S (1994) Macromolecules 27 2820 Inoue, S, Aida T (1994) Chem tech 24 28... 

In controlled polymer synthesis, in addition, it is particularly important that the control herein implies not only the simple regulation of molecular weights, MWD, and other structural factors but also the precise introduction of functional groups into specific positions of polymers with well-defined architectures. Namely, the control of one or more of these structural factors, then, leads to a variety of polymers of synthetic interest, as some of them illustrated schematically in Fig. 2 ... 

These are some thoughts and notes that came out of a symposium, Commercialization of Controlled Polymer Synthesis , San E raneisco, 1999, organized by The Knowledge Foundation. 

Novel rathenium complexes with carborane ligands were employed as efficient catalysts for controlled polymer synthesis via Atom Transfer Radical Polymerization (ATRP) mechanism. The ability of carborane ligands to stabihze high oxidation states of transition metals allows the proposed catalysts to be more active than their cyclopentadienyl counterparts. The proposed catalysts do not reqnire additives such as aluminium alkoxides. It was shown that introdnction of amine additives into the polymerization mixture leads to a dramatic increase of polymerization rate leaving polymerization controlled. The living nature of polymerization was proved via post-polymerization and synthesis of block copolymers. 

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