Naphthalimide-Tertiary Amine Derivatives as Blue-Light-Sensitive Photoinitiators

Abstract

The photochemical mechanism of the radical generation from photoinitiating systems based on 1, 8‐naphthalimide derivatives (ANDs; with tertiary amine moieties) are investigated by using various approaches including cyclic voltammetry, steady‐state photolysis, and electron spin resonance spin‐trapping techniques. It reveals that radicals can be produced from ANDs alone or ANDs/additive (e. g. iodonium salt or chloro triazine) combinations. The generated radicals and cations can initiate both free‐radical and cationic photopolymerization reactions under irradiation with various light‐emitting diodes or a halogen lamp. For most of the AND‐based photoinitiating systems, more than 60 % of acrylate or epoxide conversions were attained, and were even higher than those obtained by using commercial photoinitiators, for example, bisacylphosphine oxide or camphorquinone. More interestingly, the AND1‐based photoinitiating system can also initiate concomitant cationic/radical polymerizations and can be used for the synthesis of interpenetrated polymer networks. Show more