Metallic based polymers

Introduction of two or more terminal diyne units, either at a metal center or, for example, on an q-ring-metal complex, gives the possibility of generating metal-based polymers. In the case of alkynes, many examples of polymers have been described, but studies of similar systems derived from di- or poly-ynes are in their infancy.90 Two- and three-dimensional polymers can be constructed in similar fashion, extension leading (conceptually, at least) to the formation of novel carbon allotropes. 

Our research on the use of ROP as a route to transition metal-based polymers has been supported by the Ontario Center of Materials Research (OCMR), the ACS Petroleum Research Fund (PRF), the Natural Sciences and Engineering Research Council of Canada (NSERC), and the Institute of Chemical Science and Technology (ICST). Research on Ihe detailed properties of the polymers is being carried out in collaboration with the Polymer Materials Science Research Group of Professor G. Julius Vancso at the University of Toronto. I would also like to acknowledge and thank my very talented and enthusiastic coworkers who have carried out this research and whose names are found in the references. 1 am also grateful to the Alfred P. Sloan Foundation for a fellowship (1994-1996). 

One of the major benefits of polymer-supported catalysis is the recovery and the reuse of immobihsed catalysts, especially when dealing with chiral catalysts which can be extremely expensive [17]. Therefore effective separation methods are required [1]. However, one has to keep in mind that even the best separation technique can t overcome all the problems that can occur in polymer-sup-ported catalysis. For example, metal leaching is one major problem associated with the use and the recycHng of metal-based, polymer-supported catalytic systems and often the addition of fresh metal species to the recovered catalysts is... 

Historical Development of Metal-Based Polymer Science... 

I. Manners, Ring-opening polymerization of metallocenophanes a new route to transition metal-based polymers, Adv. Organomet. Chem., 37, 131-168 (1995). 

Other developments in the area of rigid-rod transition-metal-based polymers include the synthesis of a range of thermotropic liquid crystalline organocobalt polymers (eg, 70) in which the metal is bound to skeletal cyclobutadiene units (eq. 39) (223). 

Ni Y, Rulkens R, Manners I (1996) Transition metal-based polymers with controlled architectures well-defined poly(ferrocenylsilane) homopolymers and multiblock copolymerizadon of silicon-bridged [l]ferrocenophanes. J Am Chem Soc 118 4102-4114... 

Alkali-metal-based polymer (usually organolithium) produces a product with about 36 percent cis, 54 percent trans, and 10 percent vinyl. The polymerization process is conducted in an aliphatic hydrocarbon under an inert atmosphere in either a batch or a continuous mode. Because of the characteristics of this polymerization system, polymers of extremely narrow molecular weight distribution and low gel can be produced." The narrowest distribution is produced via batch polymerization. 

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