The comparison of various polymer based nanofibers coated recycled nonwovens on the sound absorption properties

Abstract

In recent years, the development of innovative and eco-friendly acoustic materials is increasingly important for solving noise problems in industrial and architectural areas. This study aims to determine the optimum polymer type for fabricating high performance sound absorbing nanofibers, which are to be coated onto recycled PET-based nonwoven surfaces via the electrospinning method. For this purpose, different polymer/solvent solutions such as polyvinyl alcohol (PVA), polyacrylonitrile (PAN), cellulose acetate (CA), and polyurethane (PU) were prepared. Subsequently, the viscosity, surface tension, and electrical conductivity characteristics of these solutions were investigated. In addition, the morphological structures of the nanofibers were analyzed using Scanning Electron Microscopy (SEM), and their average fiber diameters and uniformity coefficients were determined. Additionally, the air permeability and sound absorption (NRC) properties of 500 g/m² nonwovens coated with different polymer-based nanofibers were compared to an uncoated sample using the impedance tube method. It was found that the nanofiber coating significantly enhanced sound absorption by reducing air permeability from 4502 l/m²/s to 352.8 l/m²/s. Sound absorption tests were revealed that while the NRC value of the uncoated fabric was 0.105, the highest performances were achieved with PVA (0.212) and PAN (0.207) based nanofibers. PVA was selected as the optimum polymer due to its balanced sound absorption across a wide frequency range, bead free and homogenous fiber morphology, and environmental sustainability advantages provided by using DI water as a solvent.