Examples of Configurations and Conformations

Before proceeding with the development of theory and instruments, a simple but important example of chain configuration is given. This involves the difference between head-to-head and head-to-tail placement of the monomeric units, or mers, during polymerization. The head-to-tail structure of polystyrene may be written 

The trans-gauche conformations of a polymer chain can be interchanged by simple rotation about the single bond linking the moieties. The tram and 

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