Polymers (Cambridge (CIE) O Level Chemistry): Revision Note

Polymers: The Basics

• Polymers are large molecules built by linking 50 or more smaller molecules called monomers

• Each repeat unit is connected to the adjacent units via covalent bonds

• Some polymers contain just one type of unit

  • Examples include poly(ethene) and poly(chloroethene), commonly known as PVC

• Others contain two or more different types of monomer units and which are called copolymers

  • Examples include nylon and biological proteins

• Different linkages also exist, depending on the monomers and the type of polymerisation

  • Examples of linkages are covalent bonds, amide links and ester links

Diagram showing how lots of monomers bond together to form a polymer

• Poly(ethene) is formed by the addition polymerisation of ethene monomers

• Addition polymerisation involves the addition of many monomers to make a long chained polymer

• In this case, many ethene monomers join together due to the carbon carbon double bond breaking 

Poly(ethene) is formed by addition polymerisation using ethene monomers