Abstract: The photosensitivity in the expoxide system of several arene cyclopentadienyl iron tetroflouroborate salts with different structures was studied. Among them, [C₅H₅Fe₂,5 (CH₃)₂CO^-C₆H₃]BF₄ and [CH₃CO^-C₅H₄Fe₂,4 (CH₃)₂ C₆H₄]BF₄ are new compounds. The study shows that all the salts have two main absorptions near 370 and 450 nm. It also shows that those with CC group and CO group have a stronger absorption and higher photosensitivity, and can be suitable for the light cured reaction irradiated by high pressure mercury lamp. Meanwhile, the study also shows that some kinds of organic expoxides including multifunctional epoxy resins, cycloaliphatic epoxides and glycidylethers can be initiated by these salts. Heating or adding BPO could prompt the rate of polymerization significantly.

Key words: Arene cyclopentadienyl iron tetroflouroborate salts, Cationic photoinitiator, Photosensitivity