ABSTRACT
The observed effect of increasing pressure on polymerization is an increase in rate of polymerization and an increase in the molecular weight of the polymer formed. Reactions which result in the formation of macromolecules are usually classified under two broad categories, condensation and addition polymerization. Manufacturing processes for polymerization systems are usually classified as mass or bulk, suspension, emulsion and solution process. The mechanism for the polymerization is a chain reaction and in cases of commercial importance the polymer is formed from a vinyl unsaturated monomer. Addition polymerization may have an ionic species as the chain carrier. Polymerization by ionic catalysts are highly selective and may be cationic or anionic. Copolymerization reactions are of great industrial importance. The reactivity of the growing chain in copolymerization is also expected to be dependent on the nature of the "penultimate" unit of the chain-carrying radical.
