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Oxygen as a promoter of radical polymerisation of ethyl acrylate was studied in the aqueous medium. Cu2+ was chosen as the catalyst for the ascorbic acid (AA)—02 redox reaction, constituting a three component initiating system. The rate of polymerisation, Rp, was observed to increase, remain constant and then decrease with increasing [Cu2+]. Rp increased with [O2] upto ∼ 6.5 × 10−4M and thereafter remained constant. [AA] > 1.2 × 10−3M did not influence the rate. Rp always increased with monomer [M] at fixed [Cu2+], [O2] and [AA]. However, the order with respect to [M] increased with increasing [Cu2+]. The rate of polymerisation increased with ionic strength, μ and decreased with [H2SO4]. There was an initial increase in Rp followed by a decrease with increasing temperature. Conditions were identified where Rp depended only on [Cu2+] and [M] or [M] only for industrial exploitation. Kinetic chain length of the polymers obtained under various experimental conditions were determined viscometrically.

Methyl methacrylate was polymerized in aqueous medium initiated by a copper(II)-ascorbic acidoxygen system at 40°C and a kinetic study of the reaction is presented. The rate of polymerization, Rp showed an increase, constancy and then a decrease with increase in the [Cu2+]. The order with respect to [Cu2+] was 0.5 in the rate increase region. The order in monomer concentration changed gradually from 1.0 to 2.0 with increase in [Cu2+]. Rp became independent of ascorbic acid (AA) concentration and oxygen concentration at high concentrations. These results indicate that termination by mutual interaction of chain radicals predominates at low [Cu2+] while termination was exclusively by metal ions at high [Cu2+]. Rp was also observed to increase with temperature and ionic strength and to K p K t 1 2 value was calculated and compared with literature values. Chain lengths were determined by viscometry for the polymers obtained under various experimental conditions.