A new class of free radical photoinitiators based on pyrazolone azomethine dyes has been investigated. Results show that the free radical formation occurs via intermolecular electron transfer. Changes in the dye structures are translated into changes in the rate of polymerization. Dyes which have electron withdrawing substituents initiate the free radical polymerization more readily than those with electron releasing groups. The introduction of heavy atoms into the dye molecule decreases the rate of initiation of free radical polymerization.
Посилання на статтю:
Pyrazolone azomethine dyes as effective photoinitiators of free radical polymerization / Zdzislaw Kucybala and Jerzy Ppczkowski // Polymer. – 1993. – Vol 34. – P. 1558-1560.