Graphene Intercalated Multifunctional Polymer Networks as Acoustic Absorbers for Underwater Applications

Multifunctional polymer networks fortified with the power of graphene and its derivatives as nano-inclusions have excellent sound absorption efficiency in broad frequency range, high loss factor, and matching impedance with that of water along with exceptional thermal, mechanical, and tribological properties are found to be the pre-eminent material for the underwater acoustic applications, particularly for the military tactics. To develop a stealthy underwater acoustic material, various factors need to be carefully considered, including matching acoustic impedance, glass transition temperature, loss factor, tan δ value, compression set and other mechanical properties, thermal stability, adhesion, and other tribological properties, which is briefly summarized in this review. Strategical development of hybrid nano-inclusions, viscoelastic polymer networks, nanocomposites as well as various interpenetrating polymer networks (IPNs), assiduous synthesis and surface modification of graphene are pivotal key approaches that need to be appraised. Simulation studies focusing on various potential models need to be developed for the feasibility studies and designing of the underwater acoustic material.