抄録
In order to investigate the acoustical properties of hemp fibre, we measured the sound absorption coefficients of scutched and degummed hemp fibres, and compared it with other fibres using the standing wave ratio method. The effects of the thickness and bulk density of fibre assembly, the air gap behind fibre web and the diameter of fibre on the sound absorption coefficient were studied. The structural changes in hemp fibres were characterized by scanning electron microscope (SEM), Fourier transform Infrared spectroscopy (FT-IR), and X-ray diffraction (XRD). It was found that the sound absorption coefficients increased with increasing the thickness, bulk density and air gap of scutched hemp fibre assembly in the range of 125-2000 Hz, but decreased with the increase of fibre diameter, respectively. The sound absorption properties were greatly improved when scutched hemp fibres were degummed because of the separation of fibre bundles.
