Polymer and Materials Science
Wiley InterScience Backfile Collection 1832-2000
Chemistry and Pharmacology
The polymerization of styrene initiated by 2,2′-azobisisobutyronitrile has been studied in N,N-dimethylformamide solution at 60°C in the presence of hexakis(N,N-dimethylformamide) iron(III) tetrafluoroborate alone, and also in the presence of added lithium chloride. The presence of Fe(DMF)63+ ions in the polymerizing systems caused retardation, but iron(III) chloro complexes produced well defined inhibition periods. Velocity constants at 60°C for polystyryl radicals towards Fe(DMF)63+, Fe(DMF)5Cl2+, Fe(DMF)4Cl2+, and FeCl4- ions were calculated to be 847, 4.15 × 104, 6.55 × 104, and 3.14 × 104 l./mole-sec, respectively. Values of the initiator efficiency f for most systems investigated ranged from 0.59 to 0.62.
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