The Structure of Bridging Polymers

The structure of coordination polymers formed with 3,6-bis(pyridin-3-yl)-l,2,4,5-tetrazine and zinc salts can be controlled by the choice of alcoholic solvents. Infinite lattice compounds of the form [Zn2L2(N03)4(Me0H)2(//-L)] and [Zn2(/U-L)3(N03)4](CH2C12)2) have been structurally characterized. The former structure shows an alternating single- and double-bridged species whereas the latter exists as a non-interpenetrated ladder complex.273... 

Polymers containing long alkyl side chains, typically between 16 and 22 carbon atoms in length, have been used extensively as low adhesion backsizes for PSA tape products for many years. The general structure of such polymers is shown schematically in Fig. 8. The alkyl side chains are attached through a bridging group, R, to the polymer backbone, and the backbone may contain comonomers,... 

Here we have discussed only very few of the many ligands that have been studied. Many variations of substituents at the cyclopentadienyl ligand have been studied, and there are more to come as well as variation in the structure of the bridge, the anions, and the central metal. In summary, the toolbox is quite extensive prediction of properties of new polymers to be made can guide the catalysis research in the design of new catalysts. 

In the case of co-polymers with cyclic olefins other than NB, Naga et al. performed the co-polymerizations of ethylene or propylene with cyclopentene by using a number of bridged metallocene catalysts, and then investigated the peak melting temperatures and crystalline structures of the resultant co-polymers, all containing cyclopentane units. In 2004, Waymouth and Lavoie reported on the catalytic properties of a series of... 

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