Optimization of sound absorption coefficient of polyurethane foam by graphene oxide impregnation: simulation-based prediction & experimental verification

The sound absorption performance of graphene oxide (GO) impregnated polyurethane (PU) foam was studied. PU foams are fabricated to have a wide range of GO loading density by step-by-step impregnation method. It was determined that the flow resistance and the sound absorption coefficient were increased as a function of GO loading, and other foam properties as well. In addition to impregnating GO with a simple structure, a method for optimizing the spatial arrangement of GO impregnated PU was presented. The impregnation structure with the optimal sound absorption rate was suggested by controlling the impregnation structure in the multilayer structure of the porous polyurethane sponge. To this end, we developed a computer algorithm to find the optimal sound absorption structure. Through the simulation, the noise reduction coefficient (NRC) between 500 Hz to 4 kHz was maximized as 0.91 by only 54mm thick PU foam, which was verified by the impedance tube measurement. Also, various possibilities were revealed through extensive experiments and simulations.