Photochromic and photo-luminescent nano microsphere with core-shell structure and preparation method thereof

Abstract

The invention discloses a photochromic and photo-luminescent nano microsphere with a core-shell structure and a preparation method thereof. The nano microsphere comprises an inner core and an outer shell, the inner core is an organic rare earth complex (rare earth luminescence centers are Tb and Eu, a first ligand is a benzoic acid compound comprising benzoic acid, p-methoxy benzoic acid and p-toluic acid, and a second ligand is phenanthroline), and the shell is coated with a layer of SiO2. The surface of SiO2 is grafted with a layer of high-molecular color-changing material, wherein a high-molecular main chain is a vinyl polymer (including polymethyl methacrylate, polyacrylic acid and polymethacrylic acid), and a color-changing unit on a branched chain is a spiro-pyrane photochromic unit, so that a composite multi-layer core-shell structure is formed. The nano microsphere is uniform in particle size, good in dispersity and good in thermal stability, can emit red, green and yellow fluorescence under ultraviolet irradiation, has long fluorescence life, high color change speed and long color retention time, and has important significance in serving as a clothing material.

Description

technical field [0001] The invention relates to the field of nanocomposite materials, in particular to a photochromic and photoluminescent nano microsphere with a core-shell structure and a preparation method thereof. Background technique [0002] Rare earth elements are a huge treasure trove of luminescent materials. Among the various luminescent materials developed by humans, rare earth elements play a very important role. Rare earth luminescent materials have played a milestone role in the development of luminescent optics and luminescent materials. The unique structure and properties of rare earth ions make them have the advantages of high luminous intensity, pure fluorescent color, low excitation energy, high fluorescent efficiency, and easy solubility in organic media after they are coordinated with organic ligands. It is considered to be the most promising type of luminescent material. However, the biggest disadvantage of pure rare earth organic luminescent material...

AI Technical Summary

Problems solved by technology

Among them, spiropyran-based photochromic materials have been widely concerned due to their fast color change, but they have disadvantages such as poor photostability and insufficient thermal stability in practical applications.

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