Tunable network architecture in a hydrogel with extreme vibration damping properties.

Damping technologies aim to control the loads and deformations generated by ambient or forced vibrations in structures and machineries used in transport applications and construction. Traditionally, the materials used in damping devices are of fossil origin, but viscoelastic biobased resources are an alternative source of damping materials. Here, we develop an alginate-based hydrogel system with diverse porosity topologies by including poloxamer 407 as a sacrificial porogen at varying concentrations. Vibration transmissibility tests and dynamic mechanical analysis reveal these gels exhibit loss factors between 16% and 28% in the 100-300 Hz frequency range and that the dynamic modulus increases over an order of magnitude compared to the static modulus, reaching approximately 3 MPa. The visco- and poroelastic and pneumatic-like effects from the tunable porous structures contribute significantly to this damping effect. Furthermore, these hydrogels are biosourced and biodegradable, providing a sustainable alternative to conventional fossil-based damping materials.