Highly Stretchable, Transparent Hydrogel for Electromagnetic Interference Shielding

The demand for transparent electromagnetic interference (EMI) shielding materials has intensified, driven by the shortcomings of conventional transparent shielding materials, which exhibit limited light transmittance properties and struggle to perform effectively in complex environments. Herein, a conductive, stretchable, and adaptable P(AM -co -AA) hydrogel is developed by cross-linking acrylamide (AM) with acrylic acid (AA). The hydrophilic groups contained in AA and AM endow the hydrogels a light transmission of over 80%. The introduction of carboxyl group and acyl amino group provides a good hydrogen bonding environment, and the rich polymer network structure formed by appropriate monomer ratio is more conducive to the mechanical properties and EMI shielding properties of hydrogels. The P(AM -co -AA) hydrogel demonstrates favorable mechanical properties, boasting a maximum strain at break of 1322%. Additionally, the EMI shielding performance of the hydrogel is as high as 37 dB. Even when subjected to external forces, the hydrogel maintains a total shielding effectiveness of 20 dB at a strain level of 150%. In this work, ideas are provided to prepare stretchable and transparent hydrogel with excellent EMI performance for complex application environment.