How Polymers Are Made: Addition Polymerisation
Part of Polymers — GCSE Chemistry
This deep dive covers How Polymers Are Made: Addition Polymerisation within Polymers for GCSE Chemistry. Revise Polymers in Bonding & Structure for GCSE Chemistry with 20 exam-style questions and 20 flashcards. This topic appears regularly enough that it should still be part of a steady revision cycle. It is section 2 of 11 in this topic. Use this deep dive to connect the idea to the wider topic before moving on to questions and flashcards.
Topic position
Section 2 of 11
Practice
20 questions
Recall
20 flashcards
🔬 How Polymers Are Made: Addition Polymerisation
Addition polymerisation is the most common way small molecules join to make polymers. It works like this:
• The monomer molecule must contain a C=C double bond
• Under heat and pressure with a catalyst, the double bond "opens up"
• One of the two bonds in the double bond breaks
• This creates two "dangling" bonds that can attach to other monomers
• Each monomer uses its broken double bond to connect to the next
• The chain grows: monomer + monomer + monomer + ... = polymer
• Thousands of monomers join to make one giant chain
• No atoms are lost — "addition" means everything is added in
• Monomer: CH₂=CH₂ (ethene — has a double bond)
• Polymer: -[CH₂-CH₂]ₙ- (poly(ethene) — n means repeated many times)
• Used in: plastic bags, bottles, containers
• The double bond becomes a single bond in the polymer chain
• Poly(propene): from propene (CH₃CH=CH₂) — car bumpers, ropes
• PVC (polyvinylchloride): from chloroethene — pipes, window frames
• Poly(tetrafluoroethene) (PTFE): from CF₂=CF₂ — non-stick coatings (Teflon)
Naming rule: The polymer is named from its monomer — just add "poly" in front and put the monomer name in brackets: ethene → poly(ethene), propene → poly(propene).