How Polymers Are Depicted

Polymers are among the most complicated molecules known. They may contain thousands of atoms in the main chain, plus complex clusters of atoms that form the side groups attached to the skeletal units. How, then, can we depict such molecules in a manner that is easy to comprehend  

an enormous simplification can be achieved if we remember that most synthetic polymers contain a fairly simple structure that repeats over and over down the chain. This simplest repetitive structure is known as the repeating unit, and it provides the basis for an uncomplicated representation of the structure of the whole polymer. 

The naming of polymers in this book follows an accepted practice used by the vast majority of polymer chemists (though not by specialists in nomenclature). In the system used here, the name of the repeating unit is preceded by the word poly. If parentheses or brackets are needed to avoid ambiguity, they are used. If not needed, they are left out. For example, Polymer 1.5 is named poly(dichlorophosphazene), Species 1.6 is called poly(dimethylsiloxane), and Polymer 1.7 is poly(methylphenylsilane). Species 1.8 is polysulfur. 

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