Chapter 15. Polymers Chemistry Class 12 Chapter 15 Polymer Class 12 Chemistry | Page 2

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 . e . g .,
Polymerisation
The process by which the monomers get combined and transformed into polymers . is known as polymerisation .
n [ Monomer ] → Polymer
Difference between Polymers and Macromolecules
Polymers are also called macromolecules due to their large size but converse is not always true . A macromolecule mayor may not contain monomer units , e . g ., chlorophyll ( C55H72O5N4Mg ) is a macromolecule but not a polymer since there are no monomer units present so we can conclude that all polymers are macromolecules while all macromolecules may not be polymers in nature .
Classification of Polymers Based on Source of Origin
( i ) Natural polymers : Those polymers which occur in nature . i . e ., in plants or animals . are called natural polymers .
( ii ) Synthetic polymers : The polymers which are prepared in the laboratory are known as synthetic polymers or man-made polymers , e . g ., polythene , synthetic rubber , PVC , nylon-66 , teflon , orlon etc .