PHOTOSENSITIZED CATIONIC POLYMERIZATION USING N-ETHOXY-2-METHYLPYRIDINIUM HEXAFLUOROPHOSPHATE


YAGCI Y. , LUKAC I., SCHNABEL W.

POLYMER, cilt.34, ss.1130-1133, 1993 (SCI İndekslerine Giren Dergi) identifier identifier

  • Cilt numarası: 34 Konu: 6
  • Basım Tarihi: 1993
  • Doi Numarası: 10.1016/0032-3861(93)90762-y
  • Dergi Adı: POLYMER
  • Sayfa Sayıları: ss.1130-1133

Özet

The cationic polymerization of cyclohexene oxide is initiated at room temperature upon irradiation at lambda(inc) > 350 nm of CH2Cl2 solutions containing N-ethoxy-2-methylpyridinium hexafluorophosphate (EMP+PF6-) and one of the following compounds: thioxanthone, anthracene, perylene or phenothiazine. Poly(cyclohexene oxide) of molar mass exceeding 10(5) is produced. In the absence of EMP+PF6-, which is transparent at lambda(inc) > 350 nm, these sensitizers are ineffective. Acetophenone and benzophenone do not act as sensitizers. An initiation mechanism involving electron transfer from the excited sensitizers to EMP+ ions is proposed. In flash photolysis experiments, electron transfer was evidenced by the formation of radical cations in the cases of anthracene, perylene or phenothiazine.