Thioxanthone dicarboxamide derivatives as one-component photoinitiators for near-UV and visible LED (365-405 nm) induced photopolymerizations

A series of thioxanthone dicarboxamide derivatives (TX-DCAs) containing hydrogen donors as one-component photoinitiators (PIs) have been prepared. In particular, the photoreactivity of these PIs was remarkably improved due to the covalent binding of the N-phthalimido derivative and type II chromophore thioxanthone. These derivatives exhibit interesting shifted absorption so that they can be utilized as versatile PIs upon exposure to various violet and visible LEDs (365 nm, 385 nm, 395 nm and 405 nm), and can efficiently actuate the free radical photopolymerization of acrylates.