Ultralight, Heat‐Insulated, and Tough PVA Hydrogel Hybridized with SiO2@cellulose Nanoclaws Aerogel via the Synergy of Hydrophilic and Hydrophobic Interfacial Interactions

Abstract

AbstractLightweight porous hydrogels provide a worldwide scope for functional soft mateirals. However, most porous hydrogels have weak mechanical strength, high density (>1 g cm−3), and high heat absorption due to weak interfacial interactions and high solvent fill rates, which severely limit their application in wearable soft‐electronic devices. Herein, an effective hybrid hydrogel‐aerogel strategy to assemble ultralight, heat‐insulated, and tough polyvinyl alcohol (PVA)/SiO2@cellulose nanoclaws (CNCWs) hydrogels (PSCG) via strong interfacial interactions with hydrogen bonding and hydrophobic interaction is demonstrated. The resultant PSCG has an interesting hierarchical porous structure from bubble template (≈100 µm), PVA hydrogels networks introduced by ice crystals (≈10 µm), and hybrid SiO2 aerogels (<50 nm), respectively. PSCG shows unprecedented low density (0.27 g cm−3), high tensile strength (1.6 MPa) & compressive strength (1.5 MPa), excellent heat‐insulated ability, and strain‐sensitive conductivity. This lightweight porous and tough hydrogel with an ingenious design provides a new way for wearable soft‐electronic devices.