Reversible Information Storage Based on Rhodamine Derivative in Mechanochromic Cholesteric Liquid Crystalline Elastomer

With the demand for the diversity and security of information deliveries increasing, advanced security tag for data encryption has attracted great interest from the scientific community. It is promising to achieve composite dynamic information storage by the combination of multisource stimuli-responsive mechanism. Here, mechano- and chemochromism cholesteric liquid crystal elastomers (CLCEs) are prepared by introducing a rhodamine lactam-based functional trigger by two different strategies, one of which is one-pot method and another is postfunctionalization method. The performances of the CLCEs from two strategies are investigated, which are demonstrated to be effective methods in endowing material with new function, and suitable for different application scenarios. The composite material combines the force-induced structural periodicity variation of CLCE and the pigmentary and fluorescent properties changes of the functional trigger caused by the chemical environment. The orthogonal construction of dynamic structural color pattern and reversible pigmentary and fluorescent colors pattern enable the information in the CLCE to display double encryption mode, which exhibits great potential in the information storage and anti-counterfeiting. Schematic diagram of the mechanical and acid discoloration mechanism of cholesteric liquid crystal elastomer (CLCE) film and the programmable dual-response encryption film processing on this basis. The CLCE film exhibits a dynamic structural color pattern and a reversible pigment color pattern under daylight and emitted aurantia-patterned fluorescence under ultraviolet light. image