Polymerization is the chemical process in which many small molecules called monomers join together to form a much larger molecule known as a polymer.
It’s basically the “assembly process” that strings the building blocks (monomers) into long chains or networks (polymers).
Main Types of Polymerization:
- Addition Polymerization (or Chain-Growth)
- Monomers add to each other without producing any by-product.
- Usually involves monomers with double bonds (like alkenes).
- Example: Ethene (C₂H₄) → Polyethylene (plastic bags, bottles).
- Condensation Polymerization (or Step-Growth)
- Monomers join together, but a small molecule (like water, HCl, or methanol) is released each time a bond forms.
- Example: Hexanedioic acid + Hexane-1,6-diamine → Nylon (plus water).
Why it matters:
- Nature uses polymerization to make proteins (from amino acids), DNA (from nucleotides), and polysaccharides (from sugars).
- Industry uses polymerization to make plastics, fibers, rubbers, and resins.