Question

Define polymerization?

Answer 1

Polymerization:

• 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 (${\left({\mathrm{C}}_3{\mathrm{H}}_6\right)}_{\mathrm{n}}$) polypropene from (${\mathrm{C}}_3{\mathrm{H}}_6$) propene, and (${\left({\mathrm{C}}_2{\mathrm{H}}_4\right)}_{\mathrm{n}}$) polythene from (${\mathrm{C}}_2{\mathrm{H}}_4$) 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 (${\mathrm{C}}_6{\mathrm{H}}_{16}{\mathrm{N}}_2$) with adipic acid (${\mathrm{C}}_6{\mathrm{H}}_{10}{\mathrm{O}}_4$).