Polymer - Polymer Synthesis

Polymer Synthesis

Polymerization is the process of combining many small molecules known as monomers into a covalently bonded chain or network. During the polymerization process, some chemical groups may be lost from each monomer. This is the case, for example, in the polymerization of PET polyester. The monomers are terephthalic acid (HOOC-C₆H₄-COOH) and ethylene glycol (HO-CH₂-CH₂-OH) but the repeating unit is -OC-C₆H₄-COO-CH₂-CH₂-O-, which corresponds to the combination of the two monomers with the loss of two water molecules. The distinct piece of each monomer that is incorporated into the polymer is known as a repeat unit or monomer residue.