Condensation Polymerisation
Polymerisation in which monomers join with the elimination of a small molecule, usually water.
Formula / equation
n A + n B → –(AB)ₙ– + n H₂O
Unit
Dimensionless
In depth
Each monomer needs two functional groups so the chain can grow at both ends. Because a small molecule is lost at every step, atom economy is below 100%, and the resulting polymer contains ester or amide links that can be hydrolysed back.
Examples in the real world
Nylon-6,6 from a diamine and a diacid; PET from ethane-1,2-diol and benzene-1,4-dicarboxylic acid.