Facile Image Patterning via Sequential Thiol-Michael/Thiol-Yne Click Reactions

Freestanding substrates with high refractive index modulation, good oxygen resistance, and low volume shrinkage are critical in photolithography for the purpose of high density data storage, image patterning and anticounterfeiting. Herein, we demonstrate a novel paradigm of direct holographic image patterning via the radical-mediated thiolyne click reaction subsequent to the base-catalyzed thiol-Michael addition reaction. With the benefit of a newly synthesized alkyne monomer, 9-(2-((2-(prop-2-yn-1-yloxy)ethyl)thio)ethyl)-9H-carbazole (POETEC), holograms with as high as 96% diffraction efficiency, refractive index modulation of 0.0036, dynamic range of 5.6 per 200 mu m and volume shrinkage of 1.1%, are successfully patterned in an aerobic environment. Uniquely and distinctly, an inhibitor is unnecessary to prevent the initiation of the sequential reaction in this framework.