Polymers (AQA GCSE Combined Science: Trilogy): Revision Note Exam code: 8464

Polymers (AQA GCSE Combined Science: Trilogy): Revision Note

Exam code: 8464

What is a polymer?

  • Polymers consist of very large molecules

  • The are made by linking together large numbers of smaller molecules called monomers

  • The atoms in the polymer molecules are linked to other atoms via strong covalent bonds

  • The intermolecular forces acting in between polymer chains are larger than those in between simple molecules so polymers are usually solid at room temperature

  • Examples of polymers include polythene and polychloroethene, commonly known as PVC

Diagram of a polymer chain

An example of a polymer chain

Polymers are made from very long carbon chains

Drawing polymers

  • Polymers are made up of repeat units

  • The monomer ethene, and the repeat unit for poly(ethene) are shown below. 

  • In a repeat unit, the bonds on either side of the polymer must extend outside the brackets (these are called extension or continuation bonds)

  • A small subscript n is written on the bottom right hand side to indicate a large number of repeat units

Ethene and poly(ethene)

The simplest of all polymers is poly(ethene)

  • The monomer 1,2-dichlorethene forms the polymer (poly)1,2-dichlorethene

1,2,-dichloroethene and the formation of its polymer

The structure of poly(chloroethene) and its monomer

Examiner Tips and Tricks

For paper 1 of your chemistry exam, you must only be able to recognise polymers from diagrams, you do not need to be able to draw polymers or their repeat units.

Polymers are covered in more detail in the organic chemistry section of paper 2. 


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