Fabrication and characterization of bimetallic Zn/Co zeolitic imidazolate frameworks-functionalized polyurethane/3D spacer fabric composites for noise control applications
Journal of Building Engineering, cilt.130, 2026 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 130
- Basım Tarihi: 2026
- Doi Numarası: 10.1016/j.jobe.2026.117053
- Dergi Adı: Journal of Building Engineering
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Compendex, INSPEC
- Anahtar Kelimeler: 3D spacer fabric, Airflow resistivity, Metal-organic frameworks, Polyurethane foam, Sound absorption
- Orta Doğu Teknik Üniversitesi Adresli: Hayır
Özet
Lightweight and moisture-tolerant sound absorbers are essential for modern noise-control applications where flexibility and mid-frequency performance are critical. In this work, polyurethane foams (PUFs) were functionalized with mono- and bimetallic zeolitic imidazolate frameworks (ZIF-8, ZIF-67, and ZIF-67-8) and further integrated with a 3D knitted spacer fabric (3DSF) to form hybrid acoustic composites. The ZIF particles were uniformly dispersed within the polyurethane network via in situ incorporation, leading to controlled modifications in cell-wall roughness and surface chemistry. FESEM and elemental mapping confirmed homogeneous distribution of both Zn and Co in the dual-metallic ZIF-67-8 system, which produced a fine and continuous nanostructured coating. The resulting composites exhibited enhanced hydrophobicity (contact angle up to 132°) and tunable airflow resistivity (3.0-6.0 × 104 Pa s m−2). Acoustic measurements using the impedance-tube method revealed a substantial improvement in mid-frequency sound absorption. While pristine PUF exhibited limited normalized sound absorption coefficients (SAC) of 0.016 and 0.045 per mm at 2 and 4 kHz, respectively, the bimetallic PUF@ZIF-67-8 achieved higher and more balanced SAC values of 0.017 and 0.054 per mm. Notably, the 3DSF/PUF@ZIF-67-8 composite demonstrated the best performance, reaching normalized SAC values of 0.043 at 2 kHz and 0.045 at 4 kHz, and forming a broad absorption plateau in the 2-4 kHz range relevant to speech and indoor noise control. These findings demonstrate a scalable strategy for designing lightweight, flexible, and moisture-tolerant acoustic composites through synergistic microstructural and architectural engineering.