Some studies on the photo-initiated cationic polymerisation of epoxides

✍ Scribed by R.S. Davidson; J.W. Goodin

• Book ID: 103075368
• Publisher: Elsevier Science
• Year: 1982
• Tongue: English
• Weight: 490 KB
• Volume: 18
• Category: Article
• ISSN: 0014-3057
• DOI: 10.1016/0014-3057(82)90036-2

✦ Synopsis

Several triarylsulphonium and diaryliodonium compounds have been synthesised. Alkylarylsulphonium compounds were obtained by alkylating diaryl sulphides with trialkyloxonium salts and by reaction of diaryl sulphides with alkyl halides in the presence of silver tetrafluoroborate. Photolysis of the sulphonium salts in methanol gave diaryl sulphides and, in the case of triarylsulphonium compounds, the appropriate aromatic hydrocarbon and its methyl ether. Diaryliodonium tetrafluoroborates and pentafluorophosphates gave aryl fluorides, biaryls and aromatic hydrocarbons. The decomposition of the salts is suggested as occurring via both free radical and ionic pathways. The ability of the compounds to sensitise the polymerisation of epoxy resins was found to be dependent upon the counterion (hexafluorophosphates being more efficient than tetrafluoroborates) and upon the structure of the cation. Sensitised cationic initiated polymerisation was also investigated and it was found that both excited singlet state and triplet state sensitisers were effective.