Kinetics of radical polymerization—XXXII. Determination of the rate of initiation in bulk polymerization of acrylonitrile

Kinetic study of methacrylate copolymerization systems by thermoanalysis methods

“…Inhibitors react with the initiating and propagating radicals, converting them into either nonradical species or radicals of very low reactivity to undergo propagation. The stable free radical 2,2‐diphenyl picryl hydrazyl (DPPH) is a powerful inhibitor for the polymerization of either monomer, but its inhibition efficiency is highly sensitive to the presence of dissolved oxygen 7. In typical polymerization systems, the monomer concentration is about 10 4 times the inhibitor concentration, and the propagation constant of primary radicals toward the monomer is about 10 −2 to 10 −3 times of the reaction with the inhibitor.…”

“…Although polymerization reactions are highly exothermic, in the case of complex energetic reactions, kinetic analysis based on DSC data needs some consideration; the peaks may be a balance among exothermic and endothermic events, and so the kinetic evaluations may be problematic. The application of DSC to the kinetic study of homopolymerization was developed by Horie5 as well as other investigators 6, 7. The application of DSC to the kinetic studies of copolymerization systems is less clear‐cut.…”

Kinetic study of an in situ inhibited polymerization using robust M-statistics

“…In reacting systems, DSC provides a continuous history of the heat evolved during the reaction. While the kinetic study of the copolymerization systems by DSC is less clear-cut, the application of DSC for kinetic study of homopolymerization was developed by Horie et al (1970) as well as other investigators (Sebastian and Biesenberger, 1979;Rehak and Tudos, 1980). Horie et al (1970) analyzed the DSC results of copolymerization systems which both comonomers have equal heats of reaction.…”

“…Inhibitors first used in polymerization experiments to establish an initial baseline for thermo-analysis curves. The stable free radical 2,2-diphenyl picrylhydrazyl (DPPH) is an effective inhibitor for polymerization of either monomer, but its inhibition efficiency is highly sensitive to the presence of the dissolved oxygen (Rehak and Tudos, 1980). In a typical polymerization system, the monomer concentration is about 10 4 times than the inhibitor concentration and the propagation constant of primary radicals toward monomer is about 10 −2 to 10 −3 times of the reaction with inhibitor.…”