- Polymerization is defined as the chemical process in which the monomers are joined together to form polymers.
- Normally, it takes several thousands of monomers to make a single polymer.
There are two types of polymerization:
(a) Addition polymerisation:
- When the monomers are added together with the help of a catalyst it is known as addition polymerization.
- The formation of addition polymers occurs by the repeated addition of monomer molecules that possess triple or double bonds.
- For example, the formation of () polypropene from () propene, and () polythene from () ethene.
(b) Condensation polymerization:
- When the monomers are added together with the byproduct and require two different types of monomers that join alternately, it is known as condensation polymerization.
- The formation of condensation polymers occurs by the repeated condensation reaction between two different tri-functional or bi-functional monomeric units.
- In this type of reaction, small molecules such as alcohol, water, hydrogen chloride, etc. are eliminated.
- Few examples, are nylon 6, nylon 6, 6, terylene (dacron), etc.
The formation of nylon 6, 6 occurs due to the condensation of hexamethylene diamine () with adipic acid ().