ABSTRACT

The behaviour as radical polymerisation photoinitiators of the xanthene dyes succinylfluorescein, some of its halogenated derivatives, and an ester of Eosin with an 0-benzoyl-α-oxooxime group, has been studied by differential scanning photocalorimetry under different experimental conditions, using 2-hydroxyethyl methacrylate as monomer, in a work directed toward the search of more efficient photoinitiator systems under visible light irradiation. Under comparative conditions, the polymerisation rates obtained with the new dyes were similar to, or as much as 4.5 times higher (in the case of the Eosin ester) than those reached with the related dye Eosin, taken as a reference. The implied mechanisms of action are discussed.