Thin-slice structure enhanced hyperelastic composite foams for superb sound absorption and thermal insulation

With the ongoing advancement of society, the populace’s needs for goods are progressively evolving from essential to comfy. Within the construction sector, the demands for building materials with exceptional sound absorption and thermal insulation capabilities are becoming increasingly expected by consumers. Herein, the melamine foam (MF) and carboxymethyl cellulose (CMC) were combined through a facile dip-coating method. Benefitting from the unique three-dimensional porous structure and the folded pore walls caused by CMC, the composite foam with thin-slice structure exhibited a high sound absorption capacity with a noise reduction coefficient of 0.424 (thickness = 20 mm). In particular, compared to the unmodified MF, the sound absorption performance of the composite foam was increased by approximately 94.3 % at 500 Hz and 211.2 % at 1000 Hz. Furthermore, it also demonstrated outstanding thermal insulation ability with low thermal conductivity of 0.0319 W/mK and thermal diffusivity of 0.855 mm²/s. When placed on a heating platform of 145 °C, the temperature difference between the upper and lower surfaces of the composite foam reached an impressive 105.1 °C. Based on these advantages, this high-performance composite foam possesses great potential for applications in engineering, construction, noise reduction, and personal protection.