Polymerisation reactions
Compounds that contain the C=C double bond can be polymerised. This type of reaction is known as an addition reaction as the alkene molecules are adding together. These reactions normally need to occur under high pressure and temperature.
When alkene molecules are used in polymerisation there normally known as monomers. They written with poly in front of the name of the alkene, for example poly(Butene). Even though the polymer formed is saturated we still use the 'ene' at the end of the name.
When alkene molecules are used in polymerisation there normally known as monomers. They written with poly in front of the name of the alkene, for example poly(Butene). Even though the polymer formed is saturated we still use the 'ene' at the end of the name.
Polymers don't really have a molecular formula, their molecular masses are too big. So we have to use a different method. We use a letter n to represent the number of monomer molecules and putting the repeat unit in a bracket the n is placed after the bracket.
Sometimes you may have to identify the repeat unit. Below we have poly(phenylethene) commonly known as polystyrene. To look for the monomer it will be associate with two carbon atoms with atoms or groups attached to them. The monomer will be this structure, however it will have a double bond instead.
In this image you can see that the there are two hydrogen's attached to one carbon and a phenyl and hydrogen to the other carbon.
In this image you can see that the there are two hydrogen's attached to one carbon and a phenyl and hydrogen to the other carbon.
Want a challenge? (A-level only)
Take a look at the document below
Take a look at the document below