Polymers metal coordination

In this class of polymers, coordination occurs between an organic group in the polymer and a metal atom. This coordination may result in the metal atom being attached as a side group or part of a side group, or as an integral part of the chain backbone.74-78 

A simple example of the first type of polymer is polytvinyl pyridine), [-CH2CII((%n4N)-L, where the nitrogen atom in the -C5H4N side group has unpaired electrons available for coordination. Another example would be an ionic side chain, which could coordinate with a metal cation. 

Much more research has been carried out with polymers in which the coordinated metal atom is part of the chain backbone. Typically, the metal atoms are copper, nickel, and cobalt. Oxygen atoms or carbon atoms adjacent to the metal atom provide the electrons required for the coordinate bond.30 Polymers of this type are often rather intractable, for a variety of reasons. Specifically, insolubility can be a problem for species with moderate molecular weights. Also, coordination between chains can cause aggregation, and ligand-exchange reactions with small molecules such as solvents can cause chain scission. However, in some favorable cases, the intramolecular coordination is sufficiently strong for the polymer to be processed by the usual techniques such as spinning into fibers or extrusion into films.30 

In other examples, compounds in which a metal atom is already coordinated in a molecule can be used as a comonomer in an addition polymerization. Two examples involve the ferrocenes discussed in Chapter 6. The vinyl ferrocene molecule is shown in 7.14, and a similar vinyl manganese complex in 7.15.30 An alternative approach involves condensation polymerization. For example, if the R group in the ferrocene unit shown in 7.16 contains a hydroxyl group, it can be copolymerized with a diacid chloride. If it is an acid chloride, it can be copolymerized with a diamine. (This type of polymer is called a heteroannular chain if only one of the rings in the repeat unit is in the backbone, the polymer is called homoannular.)7 Similarly, the titanium complex shown in 7.17 is copolymerized with diacids or diols.30 Numerous other examples involving ferrocenes are discussed in Chapter 6. 

Some metals form coordination polymers with sulfur that have a semi-ladder structure. One series are the bisdithiocarbamate polymers, which have the typical structure shown 

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Approaches to the formation of three new types of micro-porous materials that complement zeolites will be discussed. In each case, whether metal coordination polymers, metal-linked ceramic oxide clusters, or new hybrids containing both coordination and ceramic components, engineering of the Secondary Building Unit (SBU) is of critical importance. Successful examples of these approaches include the first thermally stable 3-D micro-porous coordination polymer with chemical functionalizability [Cu3(TMA)2(H20)3] , as well as a 3-D micro-porous cluster based material [V,2B18O60H8(Cd(en)(H2O) 3]". ... 

There has been a considerable interest to develop metal coordination polymers due to their unique electronic and spectroscopic properties. Metal coordination polymers have been reported to have applications in nonlinear... 

In this chapter, we describe the synthesis of a series of self-assembled metal coordination polymers that show various color emissions from the violet to red spectral region with high PL quantum yields and good OLED efficiencies. 

The stability sequence for these divalent metal coordination polymers was reported to be Fe > Ni > Zn > Co > Cu. Thus, it is evident that different thermal stability sequences will be developed when different experimental conditions and criteria are employed. 

Cui XJ, Khlobystov AN, Chen XY et al (2009) Dynamic equilibria in solvent-mediated anion, cation and ligand exchange in transition-metal coordination polymers solid-state or recrystallization Chem Eur J 15 8861-8873... 

Shi Q., Cao R., Sun D.-F., Hong M.-Ch. and Liang Y.-C., Solvothermal syntheses and crystal structures of two metal coordination polymers with double-chain structures, Ployhedron 20 (2001) pp. 3287-3293. 

Zhou, Y, Hong, M., and Wu, X. (2006) Lanthanide-transition metal coordination polymers based on multiple N and O-donor ligands. Chemical Communications, (2), 135-143. 

Fig. 6.1. Preparation of molecular imprinted metal-coordinating polymers for Z>w-imidazole substrates.

Fig. 6.2. Synthetic strategy for the preparation of surface imprinted metal-coordinating polymers using poly(TRIM) particles.

Arnold and co-workers attempted to prepare imprinted metal-coordinating polymers for proteins [25]. For this purpose, efforts were made to prepare metalcoordinating molecularly patterned surfaces in mixed monolayers spread at the air-water interface or liposomes. This approach was termed as molecular printing and is illustrated in Fig. 6.6. In this process, a protein template is introduced into the aqueous phase, which imposes a pattern of functional amphiphiles in the surfactant monolayer via strong interactions with metal-chelating surfactant head groups. The pattern is then fixed by polymerising the surfactant tails. The technique has also been employed for two dimensional crystallisation of proteins [26]. 

Simultaneous polymerization emd crystallization is another approach to memroscopic, defect-free single crystals of macromolecules (59). Recent examples include a preparative method for mixed metal coordination polymers (60), emd M. Hemack emd coworkers have reacted hemipotphyreizine (6 with iron (II) acetate in nitrobenzene to obtain single crystals of em oxygen-bridg polymer with iron in a -i- 4 oxidation state. 

A. Abd-El-Aziz, C. E. Carraher, Jr., C. U. Pittman, Jr., and M. Zeldin (eds.), Macromolecules Containing Metal and Metal-Like Elements, Vol. 5 Metal-Coordination Polymers, Wiley Interscience, New York, 2005. 

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