Carbazolyl α-diketones as novel photoinitiators in photopolymerization under LEDs

Novel photoinitiators (α-DKs) bearing α-dicarbonyl groups as initiating group and aromatic groups as chromophore group were synthesized and developed as visible light type I photoinitiators with high performance for radical photopolymerization of acrylate. α-DKs exhibit good absorption at 405 nm and higher initiation efficiency compared with commercial initiator camphorquinone (CQ) under LED sources. Meanwhile, α-DKs were found to efficiently photosensitize bis (4-methylphenyl) hexafluorophosphate (ION) and initiate both free radical polymerization and cationic polymerization.