Study Notes
Addition polymerisation is a reaction where monomers with unsaturated bonds, like alkenes, form a polymer chain without losing any atoms.
- Addition polymerisation — a reaction where monomers with unsaturated bonds form a polymer chain. Example: Ethene molecules forming polyethylene.
- Poly(ethene) — a polymer formed from ethene monomers through addition polymerisation. Example: Polyethylene is used in plastic bags.
- Poly(chloroethene) — a polymer formed from vinyl chloride monomers through addition polymerisation. Example: PVC is used in pipes and cable insulation.
- Repeat unit — the smallest unit that repeats in a polymer chain. Example: -CH2- in polyethylene.
- Disposal of polymers — polymers are non-biodegradable and difficult to dispose of, causing environmental pollution. Example: Poly(alkenes) in landfills.
Exam Tips
Key Definitions to Remember
- Addition polymerisation: A reaction where monomers with unsaturated bonds form a polymer chain.
- Poly(ethene): A polymer formed from ethene monomers.
- Poly(chloroethene): A polymer formed from vinyl chloride monomers.
- Repeat unit: The smallest unit that repeats in a polymer chain.
Common Confusions
- Confusing addition polymerisation with condensation polymerisation.
- Misidentifying the repeat unit in a polymer chain.
Typical Exam Questions
- What is addition polymerisation? A reaction where monomers with unsaturated bonds form a polymer chain.
- How is polyethylene formed? By polymerising ethene monomers through addition polymerisation.
- Why are polymers difficult to dispose of? They are non-biodegradable and resistant to chemical attack.
What Examiners Usually Test
- Understanding of the addition polymerisation process.
- Ability to deduce repeat units from monomers.
- Environmental impact of polymer disposal.