Classification of Polymers Based on Mode of Polymerisation
Polymerisation reactions are of two types namely: i) Addition polymerization and ii) Condensation polymerization
i) Addition Polymerization: If Polymerisation occurs by the union of the monomer by bonds originally associated with unsaturation, that is double or triple bonds it is called addition Polymerisation. The polymer thus formed is called an addition polymer. During this type of Polymerisation no atoms of the monomers are eliminated. The addition polymer has the same empirical formula but higher molecular mass than the monomer.
• Examples: Polyethylene, Polystyrene, Poly Vinyl Chloride (PVC)
ii) Condensation Polymerization: If the monomer molecules combine in such away that during their union simple molecules like water, ammonia, hydrogen chloride, methyl alcohol etc are eliminated, the product is called condensation polymer. Natural polymers like starch, proteins etc are condensation polymers
• Examples: Nylon 66 and Melamine Formaldehyde
