Participation of an excited monomer in the propagation reaction of the γ-ray induced polymerization of ethylene

✍ Scribed by Hagiwara, Miyuki ;Okamoto, Hidemasa ;Kagiya, Tsutomu

• Publisher: Wiley (John Wiley & Sons)
• Year: 1970
• Tongue: English
• Weight: 373 KB
• Volume: 8
• Category: Article
• ISSN: 0449-296X
• DOI: 10.1002/pol.1970.150081123

✦ Synopsis

Abstract

In the polymerization of ethylene, the reactivity of the growing radical produced by γ‐radiation was compared with that of the radical from 2,2′‐azobisisobutyronitrile. The radicals produced in the polymerization at around room temperature were long‐lived irrespective of the method of initiation. However, it was found that the radical produced by γ‐radiation became unreactive to ethylene when the reaction system was not exposed to γ‐rays. Irradiation with γ‐rays or ultraviolet light in a region below about 3900 Å was required for its chain growth. On the other hand, the radical from AIBN was always reactive, and the reactivity was little changed by γ‐radiation or by the presence of a trace amount of radiolysis products of ethylene. In explaining of these characteristic differences between the nature of these radicals produced by two different methods of initiation, some other information on their reactivity was reviewed, and the participation of an excited ethylene in a dimer form was proposed, as for the propagation reaction of the γ‐ray‐induced polymerization.