Updatable colorful display of vector hologram in azo–poly(9‐vinylcarbazole)–TiO2 nanocomposite films. Issue 14 (30th September 2019) - Kang, Lihong
ABSTRACT: Reversible photoconversion can realize multiple utilizations of optical materials, which is essential for updatable display. Azopolymer has the ability of reversible photoconversion benefiting from its recycled trans–cis isomerization. Commonly, introduction of inorganic nanoparticles can improve the optical response rate and holographic reconstruction efficiency of azopolymer. However, aggregation of inorganic nanoparticles in azopolymers is unavoidable, not only aggravating light scattering but also reducing film homogeneity and chemical activity. It is difficult to realize reversible optical conversion in the photochromic material. Here, we use poly(9‐vinylcarbazole) (PVK) and porous TiO2 to improve optical properties of azopolymer. The spatial dispersion ability of the photosensitive units is increased greatly. Diffraction efficiency of vector‐holographic gratings in the organic–inorganic comodulated film is eight times higher than that without PVK. Erasing ratio of the stored hologram reaches 97.8%. Based on such property, updatable vector hologram reconstruction with different colors lights is realized. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48537. Abstract : Erasable vector‐hologram in azo‐PVK‐TiO2 nanocomposite films.