Synthesis of furan derivative as LED light photoinitiator: One-pot, low usage, photobleaching for light color 3D printing

A type II photoinitiator, containing furan structure, 2,6-bis(furan-2-ylmethylidene) cyclohexan-1-one (BFC) was synthesized via one step reaction between furan and cyclohexanone. This photoinitiator has large molar extinction coefficient and long wavelength absorption attributing to its large conjugation structure. Photopolymerization kinetics reveals that photoinitiator BFC at low concentration exhibits the high polymerization rate and conversion. UV-vis absorption and fluorescence spectrum demonstrate that BFC has a big red shift in the polyethylene glycoldiacrylate (PEGDA) solution and the light absorption region could be extended to 500 nm because of exciplex formed by BFC and PEGDA. Moreover, PEGDA is the excellent hydrogen donor to photoinitiator BFC compared with traditional coinitator amine. This BFC/PEGDA photoinitiator system has an outstanding photobleaching performance, which has potential to be used in the light-color materials with visible light photopolymerization, such as 3D photopolymerization printing material with long wavelength LED lamp.