Identify the type of polymer $$ -\mathrm{A}-\mathrm{B}-\mathrm{B}-\mathrm{A}-\mathrm{A}-\mathrm{A}-\mathrm{B}-\mathrm{A}- $$
Copolymer, as it contains more than one type of monomer units. Here, $A$ and $B$ are two types of monomer units.
Out of chain growth polymerisation and step growth polymerisation, in which type will you place the following.
Chain growth polymerisation, as there is no loss of small molecules like water; methanol etc.
Identify the type of polymer given in the following figure.
Cross-linked or network polymer.
Identify the polymer given below.
The given polymer is formed by', 1, 4--addition of 2- methylbuta- 1,3- diene (isoprene) and stereochemistry is 'cis' throughout. Therefore, the given polymer is 'cis'- polyisoprene i.e., natural rubber.
Why are rubber called elastomers?
They change their shape on applying force and regain their original shape on removal of the applied force. Hence, rubbers are called elastomers.