My watch list
With an accout for my.chemeurope.com you can always see everything at a glance – and you can configure your own website and individual newsletter.
My watch list
My saved searches
My saved topics
Addition polymerisation, also called polyaddition or chain growth polymerization, is a polymerisation technique where unsaturated monomer molecules add on to a growing polymer chain one at a time. It can be represented with the chemical equation:
nM (monomer) --> -(-M-) n- (polymer)
The main characteristics are:
polymerisation process takes place in three distinct steps:
chain initiation, usually by means of an initiator which starts the chemical process. Typical initiators include any organic compound with a labile group: e.g. azo (-N=N-), disulphide (-S-S-), or peroxide (-O-O-). Two examples are benzoyl peroxide and AIBN.
chain termination, which occurs either by combination or disproportionation. Termination, in radical polymerisation, is when the free radicals combine and is the end of the polymerisation process.
some side reactions may occur, such as: chain transfer to monomer, chain transfer to solvent, and chain transfer to polymer.
unlike condensation polymerisation (also known as step-growth polymerization):
high molecular weight polymer is formed at low conversion
no small molecules, such as H 2O, are eliminated in this process
new monomer adds on the growing polymer chain via the reactive active centre which can be a
the monomer molecule can be a
given special reactants and reaction conditions an addition polymerization can be considered a living polymerization.
above a certain ceiling temperature, no polymerisation occurs.
This article is licensed under the
GNU Free Documentation License. It uses material from the Wikipedia article "Addition_polymerization". A list of authors is available in Wikipedia.
Your browser is not current. Microsoft Internet Explorer 6.0 does not support some functions on Chemie.DE