Polymers

Polymer, any of a class of natural or synthetic substances composed of very large molecules , called macromolecules, which are multiples of simpler chemical units called monomers. Polymers make up many of the materials present in living organisms, including proteins, cellulose, and nucleic acids for example. In addition, they form the basis of minerals such as diamond, quartz, and feldspar, and materials such as concrete, glass, paper, plastics, and rubber. The word polymer refers to an unspecified number of units with monomer. The compound is sometimes called a high polymer, when the number of monomers is very large. Polymers are not limited to monomers of the same chemical composition or weight and structure of the molecules. All natural polymers consist of a single monomer. However, most natural and synthetic polymers are composed of two or more different monomer types; such polymers are known as copolymers.