Explain the term copolymerisation and give two examples.

(N/A) The polymerisation reaction in which a mixture of more than one monomeric species is allowed to polymerise and form a copolymer which contains units of both species is called copolymerisation. The process of forming polymer $Buna-S$ from $1,3-butadiene$ and $styrene$ is an example of copolymerisation.
$n CH_2=CH-CH=CH_2 + n C_6H_5CH=CH_2 \xrightarrow{\text{Copolymerisation}} [CH_2-CH=CH-CH_2-CH(C_6H_5)]_n$ $(Buna-S)$
$Nylon-6,6$ is also a copolymer formed by $hexamethylenediamine$ and $adipic acid$.
$n H_2N(CH_2)_6NH_2 + n HOOC(CH_2)_4COOH \to [NH(CH_2)_6NHCO(CH_2)_4CO]_n + 2n H_2O$ $(Nylon-6,6)$