Production of Acoustic Insulating Materials from Viscoelastic Mattress Waste

In this work, briquettes from mattress waste are manufactured and the acoustic properties of the materials produced are checked. Briquettes are made at temperatures between 170 and 185 °C using waste from viscoelastic memory foam (VMF) and applying pressures between 25 and 75 MPa. Later, the properties of the materials such as their bulk density, porosity, and compaction factor are measured. Afterwards, the materials are subjected to a test to determine the sound reduction index at different frequencies. This is completed with a home-made system in which the acoustic signal is compared in the presence and absence of the mattress briquettes using MATLAB® software (Mathworks, Natick, MA, USA) for signal computing. The results are also compared with a reference acoustic insulation material. The runs show that the materials produced from mattress waste are able to reduce the intensity of sound in a similar way to commercial materials. In fact, reduction indices with prepared briquettes are much higher in the frequencies that most affect the human ear, compared to a reference insulating material.