A preliminary investigation on kapok/polypropylene nonwoven composite for sound absorption

Abstract

The use of kapok fibre with polypropylene fibre for the development of sound absorptive nonwoven materials has been explored. Three different blend ratios of kapok and polypropylene fibres, namely 30:70, 40:60 and 50:50 have been used. The composites are characterized for their physical properties, namely thickness, density, porosity and sound absorption characteristics in the frequency range 250 - 2000 Hz. The values of sound absorption coefficient and noise reduction coefficient obtained indicate that the kapok fibre composites possess very good sound absorption behaviour in the entire frequency range. The uncompressed kapok/polypropylene nonwoven composite of 30:70 blend ratio with high bulk density and low porosity is found to give the best performance when used by providing air gap behind the composite.