Some new redox resins

Abstract

AbstractWith the aim to synthesize chemically stable redox polymers the following investigations have been performed. Homopolymerization investigations of nucleus‐methylated 1‐vinyl‐3,6‐diacetoxybenzenes showed that a methyl group in the 5 position seems to have a severe negative effect on the polymerizability of vinyl hydroquinone compounds. Sulfonated copolymers of the vinyl hydroquinone derivatives with styrene and DVB having ion exchange capacities of 3.4 meq./g., redox capacities of 2.1 meq./g., and midpoint potentials of 520 mv. (pH 0.36) were prepared. 2,3‐Dimethyl‐2,3‐epoxy‐5‐vinyl naphthoquinone‐(1,4) is the only polymerizable derivative of this naphthoquinone. A copolymer of epoxide, methacrylic acid, and DVB was converted to the quinone by reaction with KJ, yielding a redox copolymer with a redox capacity of 2.3 meq./g. Oxidative degradation experiments on sulfonated styrene–DVB cation exchange resins, wherein styrene and DVB are partially replaced by α‐methylstyrene and diisopropenyl‐benzene, showed that the resins become more stable as more tertiary H atoms are substituted by methyl groups. Bead‐shaped and macroreticular redox copolymers of 2‐isopropenyl‐anthraquinone‐(9,10), styrene, or methacrylic acid and DVB were prepared having redox capacities of 2–4 meq./g., ion exchange capacities of 1–4 meq./g., and midpoint potentials of 170 mv. (pH 0.2). Oxidative degradation investigations on the bases of capacity decrease and swelling increase measurements generally showed that these resins can be stabilized if a major portion of tertiary H atoms is replaced by methyl groups.