Synthesis and nonlinear optical properties of a new D-π-A two-photon photopolymerization initiator

A new two-photon polymerization initiator, 4-vinylpyridine-4′-(N,N-Diphenylamino)benene (abbreviate:VPDB) has been synthesized with inexpensive reagents. Its nonlinear optical properties were investigated in detail. The experimental results confirm that VPDB is a good two-photon absorbing chromophore and can successfully initiate two-photon photopolymerization of ethoxylated trimethylolpropane. The two-photon absorption cross-section of VPDB has been measured using the two-photon-induced fluorescence method, whose value is 14.6 × 10− 50 cm4 s photon− 1 molecule− 1. A microstructure has been fabricated by using VPDB as initiator.