Preliminary Descriptions of a Polymer Chain

A polymer chain consists of many stmctural units (repeating units or monomeric units). The chain may take on many different configurations, for example  

FIGURE 5.2 Simple model of a four-carbon chain. 

the configuration of the four-carbon chain is determined by three parameters the bond length a, the rotational angle 0, and the hindrance angle ). This model can be applied to chains containing any number of carbons greater than 3. But, as the number of bonds increases in a chain, the situation becomes more complicated. 

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