Polymers (AQA GCSE Chemistry: Combined Science)

• 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

Polymers are made from very long carbon chains

• 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

The simplest of all polymers is poly(ethene)

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

The structure of poly(chloroethene) and its monomer