Endgroup studies in poly (methyl methacrylate) initiated by redox systems containing reducing sulfoxy compounds in aqueous media

Abstract

Poly(methyl methacrylate) samples obtained by aqueous redox initiation with reducing sulfoxy compounds such as HSO₃^-, SO_2-³, S₂O_2-³, S₂O_2-⁴, and S₂O_2-⁵ in conjunction with different activators are analysed for endgroup content by the application of dye techniques, and limiting conditions for polymerization are reported in specific cases. Activators used are: (a) metal ions such as Cu²⁺, Fe³⁺, and Ag⁺ ion; (b) KClO₃ and KBrO₃; (c) H₂O₂, and (d) oxygen. Endgroups incorporated are only nonhydrolysable sulfoxy in case of (a) and (b), and both nonhydrolysable sulfoxy and hydroxyl in case of (c) and (d).