Technical noteFacile dip-coating method to prepare micro-perforated fabric acoustic absorber

Fibrous materials have been extensively used in noise reduction due to its good acoustic absorption properties and artistic appearance. Nevertheless, the acoustic absorption coefficients of woven fabrics are relatively poor in low frequency. In this study, waterborne polyurethane solution was taken to coat the woven fabrics. The results indicated that coated woven fabrics exhibited good acoustic absorption coefficients in low and middle frequency. Furthermore, the experimental values were measured by impedance tube and further compared with Maa's model. It has been found that coated woven fabrics exhibited the micro-perforated panel acoustic absorption mechanism. Dip-coating method is effective to improve the acoustic absorption properties of woven fabrics at low frequency range.