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Study on the Modes of Thermal Decomposition of Several Azo-Type Initiators


Modes of thermal decomposition reactions of several azo-type initiators were studied in the presence or absence of a transition-metal complex. Some metal complexes examined cause dramatic influence upon the relative ratio of decomposition products. Particularly, a cobalt complex prevents the coupling reaction of radicals formed from azo compounds, with increased formation of noncoupling products being observed. Futhermore no difference was observed in the mole ratios of an unsymmetrical coupling product to the sum of symmetrical products in the decomposition of an unsymmetrical azo compound with or without a complex, Co(II)(sal)2((R)-CHXDA). This phenomenon was satisfactorily explained by assuming that primary radicals immediately formed interact with the metal complex and are stabilized prior to subsequent reactions.


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Yoshino, K., Ohkatsu, Y. & Tsuruta, T. Study on the Modes of Thermal Decomposition of Several Azo-Type Initiators. Polym J 9, 275–282 (1977).

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  • Radical Decomposition
  • Azo Compound
  • Cage
  • Organometallic Complex

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