Addition polymerisation | Condensation polymerisation |
Different monomers add to form a polymer with same molecular formula of the repeating structural unit as that of starting monomer. | A large number of monomers combine with the loss of simple molecules (water, ammonia, HCl, alcohol) to form a polymer having molecular formula of the repeating unit different than starting monomers. |
No molecule is eliminated during polymerisation | Small molecules like water, ammonia, HCl or alcohol are eliminated during polymerisation. |
Usually one monomer is involved. | Two monomers are involved. |
Usually unsaturated compounds are monomers. | Usually monomers contain two functional groups. |