A novel sound absorbing material comprising discarded luffa scraps and polyester fibers

Abstract

Abstract For promoting the recycling of industrially discarded luffa resources and preventing environmental pollution caused by the incineration of luffa waste, abundant luffa scraps and environmentally friendly polyester fibers were used as raw materials to produce luffa fiber sound absorbing composites by the clean hot-pressing technology. Results revealed that the polyester fiber surface becomes rougher, with a large number of porous structures, affording a three-dimensional network after hot-pressing. Within the range of the test design, the sound absorption coefficient of the samples increased with increasing density, thickness, and distance of the back air gap. With the increase in the thickness from 2 cm to 6 cm, the average sound absorption coefficient of the material increased from 0.442 to 0.684, and the maximum sound absorption coefficient increased from 0.907 (4000 Hz) to 0.991 (1000 Hz). At back air gap distances of 0 cm, 1 cm, and 2 cm, their average sound absorption coefficients were 0.602, 0.606, and 0.645, respectively. At a density of 0.09 g/cm3, a thickness of 4 cm, and a back air gap distance of 2 cm, the average sound absorption coefficient of the luffa fiber composite reached 0.645, revealing a high-efficiency sound absorbing material. In addition to exhibiting a good sound absorption performance, the luffa fiber composite exhibited a soft surface and good buffer performance. Moreover, compared to other plant fiber composites, the luffa fiber composite exhibited better performance for hygroscopic and moisture dissipation.