Explain the classification of polymers based on their structure and mode of synthesis.

Explanation

(i) Structure :
(a) Linear polymers (long continuous chain) E.g. HDPE, PVC.
(b) Branched polymers (one main chain with small chains as branches) E.g. polypropylene, LDPE.
(c) Cross linked polymers (linking of chain polymers) E.g. bakelite, melamine, formaldehyde
(ii) Mode of synthesis :
(a) Addition polymers. Formed by polymerisation of monomers without the elimination of byproduct. E.g. polyethylene, PVC, teflon.
(b) Condensation Polymer formed by the condensation of two or more monomers with the elimination of simple molecules like `H_2O, NH_3,` etc., E.g. Nylon-66, polyester.