A study of chain‐addition polymerizations with temperature variations. IV. Copolymerizations—Experiments with styrene‐acrylonitrile

Abstract

Free-radical copolymerizations were studied under nonisothermal conditions with emphasis on their thermal runaway and ignition behavior. Computational models are presented in generalized form and compared with experiments on the system styrene-acrylonitrile. A new, useful method is proposed for the evaluation of runaway parameters from scant kinetic data. EXPERIMENTALBoth comonomers were vacuum distilled to remove commercially added inhibitors, then stored at 273K. Initiator azo-bis-isobutyronitrile (AIBN) was twice recrystallized from chloroform with methanol, dried in vacuo, and stored at 273K.The thermal ignition point apparatus (TIPA) has been described elsewhere (4). Some modifications were made

Radical Polymerization in Industry

“…Temperature control of industrial polymerizations is a very critical task because of the highly exothermic nature of RPs. In many cases, a rapid and, therefore, almost adiabatic runaway polymerization would cause temperature increase of many hundreds of degrees, 151 leading to serious consequences such as fire, reactor rupture, or environmental contamination. For example, 152 the adiabatic temperature increase at 100% conversion of monomer into polymer is 1810 • C for ethylene, 721 • C for acrylonitrile, 542 • C for vinylchloride, and 336 • C for styrene.…”

Radical Chain Polymerization

“…Local hot spots may occur, resulting in degradation and discoloration of the polymer product and a broadened molecular weight distribution due to chain transfer to polymer. In the extreme case, uncontrolled acceleration of the polymerization rate can lead to disastrous ''runaway'' reactions [Sebastian and Biesenberger, 1979]. Bulk polymerization is not used commercially for chain polymerizations nearly as much as for step polymerizations because of the difficulties indicated.…”

Synthesis and Characterization of Poly[((maleic anhydride)‐alt‐styrene)‐co‐(2‐acrylamido‐2‐methyl‐1‐propanesulfonic acid)]

“…The effect of CTC most clearly has been illustrated in radical terpolymerization of MA and its derivatives with various donor and acceptor monomers 9–15. Radical polymerization of various monomer systems in the high conversion conditions was also investigated 16–25…”