The cationic polymerization of cyclohexene oxide is initiated at room temperature upon irradiation at 2i,c>350nm of CH2C12 solutions containing N-ethoxy-2-methylpyridinium hexafluorophosphate (EMP ? PFr-) and one of the following compounds: thioxanthone, anthracene, perylene or phenothiazine. Poly(cyclohexene oxide) of molar mass exceeding 105 is produced. In the absence of EMP?PFr-, which is transparent at 2i.c > 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.
Посилання на статтю:
Photosensitized cationic polymerization using N-ethoxy-2-methylpyridinium hexafluorophosphate / Yusuf Yagci*, Ivan Luk&~tt and Wolfram Schnabel // Polymer. – 1993. – Vol 34. – P. 1130-1133.