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- PET (polyethylene terephthalate) is a condensation polymer used for plastic bottles.
- Recycling PET is challenging as high temperatures and pressures degrade the monomers.
- PET can be depolymerised back into monomers using enzymes or chemical catalysts at mild
conditions.
- Recovered monomers are re-polymerised, saving resources and energy.
Condensation Polymers
Condensation polymers form when two different monomers link, releasing a small molecule,
usually water.
Key Difference: Unlike addition polymers, condensation polymerisation produces a polymer and
water.
Forming Nylon
- Nylon is a polyamide formed from dicarboxylic acid (with two -COOH groups) and diamines
(with two -NH₂ groups).
- Each -COOH group reacts with an -NH₂ group on another monomer, forming an amide linkage
and releasing water.