Organic ChemistryHow It Works

How Addition Polymerisation Works at the Molecular Level

Part of PolymersGCSE Chemistry

This how it works covers How Addition Polymerisation Works at the Molecular Level within Polymers for GCSE Chemistry. Revise Polymers in Organic Chemistry for GCSE Chemistry with 20 exam-style questions and 14 flashcards. This topic appears regularly enough that it should still be part of a steady revision cycle. It is section 5 of 15 in this topic. Use this how it works to connect the idea to the wider topic before moving on to questions and flashcards.

Topic position

Section 5 of 15

Practice

20 questions

Recall

14 flashcards

⚙️ How Addition Polymerisation Works at the Molecular Level

Addition polymerisation works because alkene double bonds can "open up" when activated by a catalyst or high temperature and pressure. Here's the step-by-step process:

  • The double bond (C=C) in each alkene monomer opens up, allowing each carbon to form a new bond to the next monomer in the chain
  • Each monomer bonds to the monomer behind it and the monomer ahead of it, building a long chain
  • This process repeats thousands of times, building up a long polymer chain
  • The result: every carbon in the chain now has only single bonds — the polymer is saturated even though the monomer was unsaturated

Key facts about the reaction:

  • Only one product forms — the polymer (no small molecule by-product)
  • Monomers must be alkenes (contain C=C)
  • The polymer repeating unit has the same atoms as the monomer, just rearranged (all single bonds)
  • Conditions: high temperature, high pressure, and often a catalyst

Keep building this topic

Read this section alongside the surrounding pages in Polymers. That gives you the full topic sequence instead of a single isolated revision point.

Practice Questions for Polymers

What type of monomers are needed for addition polymerisation?

  • A. Molecules with two alcohol groups
  • B. Molecules with a carbon-carbon double bond (C=C)
  • C. Molecules with a carboxyl group (-COOH) only
  • D. Molecules with an amine group (-NH₂)
1 markfoundation

Explain how addition polymerisation works. Include the role of the double bond.

3 marksstandard

Quick Recall Flashcards

What is a polymer?
A large molecule made up of many repeating units (monomers) joined together
What is a monomer?
A small molecule that can be joined together to form a polymer

20 questions on Polymers — practise free

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