Backbone structure coordination polymers

Attempts to perform the cationic polymerization of vinylcyclohexane have been reported. While coordination-type polymerization of vinylcyclohexane monomer gives isotactic PCHE, polymerization under conditions that lead to the formation of carbocationic intermediates leads to polymers with a differentiated backbone structure. Instead of propagating via the vinyl carbons, the cationic polymerization proceeds via hydride shift to a tertiary carbocation, which then propagates to provide the polymer shown in Scheme 23.3 [32]. Conditions for these polymerizations typically involved the use of aluminum halide catalysts in halogenated hydrocarbon solvents at low temperatures [32,38]. For the most part, molecular weights are relatively low. 

Structure-based nomenclature can also be used when the CRU backbone has no carbon atoms. An example is the polymer traditionally named poly(dimethylsiloxane) , which on the basis of structure would be named poly(oxydimethylsilylene) or poly(oxydimethylsilanediyl) . This nomenclature method has also been applied to inorganic and coordination polymers and to double-strand (ladder and spiro) organic polymers."... 

The calculated atom displacements for the predicted reaction mode are indicated in Fig. 2, which shows the a-axis array of mutually reacting S2N2 molecules and the resulting polymer chain. The chain atom positions calculated for partially polymerized S2N2 agree with the observed atom coordinates in this material, as determined by x-ray diffrac-tion(27), to within a RMS deviation of 0.148(23). This correct prediction of reaction mode, chain backbone structure, and chain coordinates in the partially polymerized phase is a major success of the least motion calculations. 

This chapter describes the synthesis and properties of a number of classes of polymers containing metal coordination complexes in their structures. These polymers are prepared by polymerization reactions of metal-containing monomers and through metal coordination reactions. Schiff base-containing polymers (5) were one of the earUest classes of coordination polymers examined. Polymers incorporating macro-cycUc porphyrins and phthalocyanines (7) in their backbones and sidechains are known to exhibit interesting optical and electrical properties. The best-studied classes of metal-containing polymers contain bipyridyl and other related units coordinated to metal ions (8). 

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