Multifunctional Organohydrogels for pH-Responsive Fluorescent and Electrostimulus Writing.

Area of Science:

• Materials Science
• Polymer Chemistry
• Nanotechnology

Background:

• Hydrogels are promising for anticounterfeiting but suffer from poor mechanical strength and slow chemical response.
• Developing robust and responsive materials is crucial for advanced security applications.

Purpose of the Study:

• To develop a fluorescent tough organohydrogel for anticounterfeiting applications.
• To enable freeform information writing, storage, and encryption using the organohydrogel.
• To investigate the material's responsiveness to stimuli and its performance under various conditions.

Main Methods:

• Synthesized a dual-network organohydrogel by incorporating 7-methylacryloxy-4-methylcoumarin into a polyacrylamide network and intertwining it with carboxymethyl cellulose sodium.
• Investigated acid-base-mediated adjustable fluorescence through monomer transformation.
• Utilized ion printing and electrical stimulation for information storage and encryption.
• Evaluated antifreezing properties and UV-light-dependent information retrieval.

Main Results:

• A fluorescent tough organohydrogel with a dual-network structure was successfully prepared.
• The organohydrogel exhibited tunable fluorescence responsive to acid-base stimuli.
• Demonstrated freeform information storage and encryption via ion printing and electrical stimulation.
• Confirmed good antifreezing properties and UV-light-based decryption at subzero temperatures.

Conclusions:

• The developed fluorescent tough organohydrogel offers a novel platform for anticounterfeiting and information security.
• Its unique properties, including tunable fluorescence and stimuli-responsive encryption, are suitable for secure message displays.
• The material's robustness and performance at low temperatures expand its potential applications in harsh environments.