The word Polymer has a Greek origin, which means many units(parts) . Polymer is defined as a chemical substance of a high molecular mass formed by the combination of a large number of simple molecules, called monomers. The process by which the monomers get combined and transformed into polymers is known as polymerization.
1. Classification of Polymers Based on Source of Origin
i) Natural Polymers: Those polymers which occur in nature i,e.,
plants or animals, are called Natural polymers.
· Examples: Starch, Cellulose -Monomer is glucose, Proteins -Monomer is amino acids, Natural Rubber- Monomer is isoprene
ii) Synthetic Polymers: The polymers which are prepared in the
laboratory are known as synthetic polymers or man-made polymers.
· Example:
Polythene, Synthetic Rubber, Poly vinyl chloride (PVC), Nylon66, Teflon, Orlon
etc
iii) Semisynthetic Polymers: Polymers obtained by making some
modification in natural polymers by artificial means, are known as semisynthetic
polymers.
· Example: cellulose acetate(rayon), Vulcanized rubber etc.