Addition polymerization

A polymer formed by addition of monomers without elimination of any molecules is called addition polymerization.

Addition polymers are generally formed from monomers containing double or triple bonds .

For example : when a large number of ethene molecules polymerize, it gives the polymer polyethene . 

Chemical rxn : 

n CH2=CH2--------------->-(-CH2-CH2-)n 

   ( Ethene)                        ( polyethene)

n CH2=CHCl --------------> -(-CH2-CHCl-)n

 (Vinyl chloride)                (Poly vinyl chloride)