Ruta Budreckiene

Cationic Photopolymerization of 1, 2‐Epoxy‐6‐(9‐carbazolyl)‐4‐oxahexane Initiated by Sulfonium Salt and Iron Arene Complex

The photopolymerization of 1,2-epoxy-6-(9-carbazolyl)- 4-oxahexane (ECOH) initiated with dual function sulfonium salt bis [4(diphenylsulfonio)-phenyl] sulfide-bishexafluoroantimonate (Cyracure ® UVI 6974) and ( η5-2,4-cyclopentadien- 1-yl) [(1,2,3,4,5,6-η)-(1-methylethyl)benzene]-iron (+)-hexafluorophosphate (—1) (Irgacure ® 261) has been studied. Higher rate constant values and degrees of polymerization are established for the ECOH photopolymerization initiated with Cyracure ® compared with those obtained using Irgacure ® . The influence of temperature on the rate of ECOH photopolymerization, molecular weight and conversion limit is discussed. The activation energy for the photopolymerization of ECOH with the sulfonium salt has been established.

Cationic photopolymerization of carbazolyl-containing vinyl ethers

Abstract Photopolymerizations of 2-(9-carbazolyl) ethyl vinyl ether (CEVE) and (9-carbazolyl) methoxy ethyl vinyl ether (CMEVE) initiated with diphenyl iodonium tetrafluoroborate (DPIT), di( tert -butylphenyl)iodonium tetrafluoroborate (BPIT), cyclopropyldiphenylsulfonium tetrafluoroborate (CPS) and (η 5 -2,4-cyclopentadien-1-yl)[(1,2,3,4,5,6-η)-(1-methyl ethyl) benzene]-iron (+)-hexafluorophosphate(-1) (I261) were studied. It was established that the efficiency of the iodonium salts and iron–arene complex is much higher in the cationic photopolymerization of the monomers than that of the sulfonium salt. CMEVE showed higher reactivity in cationic photopolymerization than CEVE. Higher degrees of polymerization were established for the products CEVE photopolymerization compared with those of the products of CMEVE reaction. The influence of the temperature on the rate of CEVE and CMEVE photopolymerization, molecular weight and conversion limit is discussed.