Describe the differences between addition and condensation polymerisation.

Addition polymerisation involves the joining of monomers without the loss of any small molecules, while condensation polymerisation involves the loss of small molecules during the joining of monomers.

Addition polymerisation involves the joining of monomers through a process of repeated addition reactions. This process occurs when unsaturated monomers, such as ethene or propene, undergo polymerisation to form long chains of saturated polymers. This process does not involve the loss of any small molecules, and the resulting polymer has the same molecular formula as the monomer.

Condensation polymerisation, on the other hand, involves the loss of small molecules during the joining of monomers. This process occurs when two different monomers, such as amino acids or diols and dicarboxylic acids, react to form a polymer. During this process, a small molecule, such as water or hydrogen chloride, is lost as the monomers join together. The resulting polymer has a different molecular formula than the monomers.

Another key difference between the two processes is the type of functional groups involved. Addition polymerisation involves unsaturated monomers, while condensation polymerisation involves monomers with functional groups that can react with each other to form a polymer.

In summary, addition polymerisation involves the joining of monomers without the loss of any small molecules, while condensation polymerisation involves the loss of small molecules during the joining of monomers. The type of functional groups involved and the resulting molecular formula of the polymer are also different between the two processes.