Pulse radiolysis of 2-[(methacryloyloxy)ethyl]trimethylammonium chloride in aqueous solution

The early stages of the polymerization of 2-[(methacryloyloxy)ethyl]trimeth ylammonium chloride (MADQUAT) in aqueous solution were studied by pulse rad iolysis. The rate constant of the reaction of this monomer with OH. and hyd rated electron was measured as 1.5 x 10(10) and 2.2 x 10(10) dm(3)mol(-1)s( -1), respectively. The absorption spectrum of the OH. adduct to MADQUAT mol ecule appeared to have a maximum at 290 nm. Its decay depends on the monome r concentration. The shape and maximum of the absorption spectrum of electr on adduct to the monomer depend on pH of the solution. In acidic solution, radical anion is formed. It subsequently undergoes reversible protonation g iving spectrum with a maximum below 260 nm. In basic solution the spectrum has a maximum at 290 nm. In this case irreversible protonation takes place at the beta-carbon atom, giving an alpha-centred carbon radical. (C) 2000 E lsevier Science Ltd. All rights reserved.