Enhanced noise reduction of melamine foam through surface roughness induced by ZIF67 loading

Noise pollution has long been a critical challenge affecting daily life and industrial activities. Porous materials, such as melamine foam, are widely used for noise reduction due to their excellent sound absorption, low density, and facile processability. However, their sound absorption properties are often limited by the control of thickness or quality in practical applications. This study presents a polydopamine (PDA) mediated surface modification approach, in which zeolitic imidazolate framework 67 (ZIF67) are grew on melamine foam (MF) to enhance its acoustic and mechanical properties. The ZIF67/PDA/MF composite (ZPM) possesses outstanding acoustic performance with a best noise reduction coefficient (NRC) of 0.64, while maintaining sound transmission loss (STL) values exceeding 15 dB above 500 Hz and reaching a maximum of 30.95 dB at 6400 Hz. And it attains a maximum modulus of 35.1 kPa at 60% strain. These improvements stem from the optimized foam skeleton structure, micropores formed via ZIF67 deposition, and increased surface roughness that reinforces the interfacial friction damping effect. This simple yet versatile strategy can be extended to other porous materials, demonstrating significant potential for noise control in industrial, architectural, and transportation applications.