A Strong, Flexible, and Anticounterfeiting Fluorescent Composite Hydrogel from Carboxymethyl Cellulose‐Eu(III) Cross‐Linked Polyvinyl Alcohol

Abstract

Fluorescent hydrogel as an advanced material has been used for anti‐counterfeiting, probe detection, and optical devices. A facile strategy to prepare fluorescent hydrogel was developed by carboxymethyl cellulose (CMC) with Europium(III) and polyvinyl alcohol (PVA). The hydrogel formed a physical cross‐linking network under mild reaction conditions without using volatile organic chemicals. The addition of CMC‐Eu(III) improved the mechanical properties of the hydrogel. At 15% CMC‐Eu(III), the hydrogel reached its maximum tensile and compressive stress, which were 47.25±10.35 kPa and 10.14±1.90 kPa, respectively. Meanwhile, the hydrogels exhibited a 5D0→7F2 characteristic emission peak assigned to Eu3+, which emitted stable red fluorescence under 254 nm UV light. When this hydrogel was applied to paper, the paper shows hidden fluorescent dots under UV light. This additive also enhances the mechanical properties of the paper, which reveals the multifunctionality of this fluorescent hydrogel for anti‐counterfeiting and reinforcement.This article is protected by copyright. All rights reserved