Citation

Chenchen Lou, Baohu Wu, Shengtong Sun*, and Peiyi Wu*. A Transparent Acoustic Damping Hydrogel with Dual-scale Bicontinuous Microphase Separation. Chinese J. Polym. Sci. 2026, 44, 1727−1737.

Abatract

Underwater camouflage materials can be hidden either from sight by being transparent or from sound by absorbing acoustic waves, but achieving both in one material remains challenging due to their distinct chemical designs. Here we decouple these conflicting properties using a hierarchically structured hydrogel featuring unique dual-scale bicontinuous microphase separation. By precisely integrating hydrophilic and hydrophobic units, we engineer three intertwined polymer-rich and aqueous phases spanning nano-to-micro length scales. This unique nanoconfinement preserves optical clarity by minimizing light scattering while facilitating ultrahigh broadband energy dissipation. Furthermore, the hydrogel’s acoustic impedance matches that of water, maximizing sound wave incidence into the material, where the propagating waves are scattered and attenuated through viscoelastic damping within the highly tortuous hydrophilic phases. A hydrogel film only 4 mm thick can absorb nearly 78% of incident sound energy. These findings highlight molecular-engineered hierarchical phase separation as a powerful strategy for developing advanced opto-acoustic soft materials.