Sound Absorption: Dependence of Rubber Particles Impurities in Tyre Textile Fibre

In recent years, the recycling of waste materials has become significant due to the movement of the European Union toward the Green Deal and the low impact on the environment. The paper studies the possibility of Waste Tyre Textile Fibre (WTTF) for sound absorption applications. WTTF is the material generated during the end-of-life tyre recycling process, which is separated from rubber and metal parts. In this study, three different types of WTTF samples were tested in which they consist of different levels of rubber impurities. In the first case, rubber particles make up to 10 % of total mass of WTTF (WTTF10), second – 54 % (WTTF54), and third – 70 % (WTTF70). The sound absorption tests were performed using the impedance tube using a two microphone technique, under the ISO 10534-2 standard. The results showed that increasing the level of rubber particles reduces the sound absorption performance of the WTTF. It was noticed that sound absorption of the sample WTTF10 reached 0.67 at low frequencies (500 Hz), while WTTF54 reached 0.31 and WTTF70 reached 0.21. It was concluded that WTTF10 samples had on average a 61 % higher sound absorption capacity compared to the other samples. The aim of the study was to determine the rubber particles impurities in WTTF dependence on sound absorption ability of the material.