Step Growth Polymerization

If the monomers add end to end and liberate a byproduct is called Step Growth Polymerization. Here molecular weight of monomer and repeat unit is different, bi product my H₂O, CO₂, NH₃ etc.

When two or more reactive functional group reacts with each other is called condensation type polymerization. E.g.: Formation of polyester and Nylon 6,6.

There are two types of condensation type polymerization. They are:

1. A-B Type.
2. AA-BB Type.

A-B Type: A-B →B (-A.B-) A + bi-product, When two functional group react with each other and produced a bi-product is called A-B type. It is a self condensation process.

AA-BB Type: AA-BB →A (-A.B-) B, When two pair of functional group react with each other. It is not a self condensation process.