Vinyl polymerization photosensitized by anthraquinone sulfonates in aqueous solutions

Abstract

The kinetics of the photopolymerization of the vinyl monomers MMA and MA sensitized by anthraquinone sulfonate-NaCl-HClO₄ systems have been studied systematically. The wavelength 365 mμ was used for irradiation. Sodium anthraquinone-2-sulfonate and disodium anthraquinone-2,6-disulfonate were used as sensitizers, and all experiments were conducted in deaerated conditions. The polymerization was followed by the measurement of monomer disappearance (gravimetrically), rate of sensitizer disappearance (spectrophotometrically) and the chainlength of the polymer formed (viscometrically). Monomer concentration, k_ε, [NaCl], and I were varied. In the light of the experimental results a prima facie kinetic scheme was proposed. The specific rate constants for the various steps have been evaluated.