Mechanisms of Plasma Polymerization – Reviewed from a Chemical Point of View

Abstract Several reaction mechanisms have been proposed for the formation of plasma polymers, such as monomer fragmentation followed by poly‐recombination into randomly structured and crosslinked films; fragmentation, accompanied by the formation of acetylene or other film‐forming intermediates and deposition of polystyrene‐like material; plasma‐initiation of a radical chain‐growth polymerization; and ion‐molecule reactions, as well as ionic chain‐growth polymerization. The bulk structure of plasma polymers is completely irregular, far from that of conventional polymers. The retention of functional groups during plasma polymerization tends to be greater than that of the entire monomer structure found again as an intact repeat unit in the resulting plasma polymer. An alternative method for depositing ultra‐thin, pin‐hole free coatings, ones that possess regular structures, is by electrospray ionization (ESI) of pre‐fabricated polymers. magnified image