Bonding & Structure


  • Polymers are large molecules of high relative molecular mass and are made by linking together large numbers of smaller molecules called monomers.
  • Each monomer is a repeat unit and is connected to the adjacent units 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.
  • Some polymers called homopolymers contain just one type of unit.
  • Examples include polythene and polychloroethene, commonly known as PVC.
  • Others contain two or more different types of monomer units which are called copolymers.
  • Examples of copolymers include synthetic rubber used in the production of disposable gloves and car tyres.
  • Many everyday materials such as resins, plastics, polystyrene cups, nylon etc. are polymers.
  • These are manufactured and are called synthetic polymers.
  • Nature also produces polymers which are called natural or biological polymers.
  • Examples include DNA, proteins, silk and wool.


  • Polymers are represented using a specific notation which is shown below using polythene as an example.
  • 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.

Making Polythene, IGCSE & GCSE Chemistry revision notes

Polymerisation of ethene monomers produces polythene

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Morgan Curtin Chemistry

Author: Morgan

Morgan’s passion for the Periodic Table begun on his 10th birthday when he received his first Chemistry set. After studying the subject at university he went on to become a fully fledged Chemistry teacher, and now works in an international school in Madrid! In his spare time he helps create our fantastic resources to help you ace your exams.