Polymers
Year 10 (IGCSE) 🌿 Materials & Environment Describe addition and condensation polymerisation with examples.
🧱 Addition Polymerisation
Monomers with C=C double bonds link together. No other product is formed.
Addition Polymerisation
$$n(\text{CH}_2{=}\text{CH}_2) \rightarrow (-\text{CH}_2-\text{CH}_2-)_n$$Poly(ethene) from ethene | Poly(propene) from propene | PVC from chloroethene.
🔗 Condensation Polymerisation
Monomers react, releasing a small molecule (H₂O or HCl) with each link.
Nylon (polyamide): diamine + diacid → polyamide + H₂O
Polyester (PET): diol + diacid → polyester + H₂O
Both monomers must be bifunctional (two reactive groups).
Polyester (PET): diol + diacid → polyester + H₂O
Both monomers must be bifunctional (two reactive groups).
🌍 Environmental Issues
Most synthetic polymers are non-biodegradable — they persist in landfill and oceans for hundreds of years.
Solutions: mechanical recycling, chemical recycling, biodegradable polymers (e.g. PLA from corn starch), reduced consumption.
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Interactive Demonstration — Polymers
See how monomers join to form polymers by addition or condensation polymerisation.
🧱 Polymer Identifier
Calculate the number of monomer units in a polymer chain.