The development of new sound absorbing materials and the transition to net zero emissions production have become inseparable. This paper investigates a new type of composite sound absorbing material made of waste tyre textile fibre (WTTF) and different binders: polyurethane resin (PU), polyvinyl acetate (PVA), and starch (POS). Non-acoustic and acoustic parameters were studied, and life cycle assessment was performed for the considered composite sound absorbing materials. The airflow resistivity was determined according to the ISO 9053-1 standard, while the sound absorption coefficient was determined according to the ISO 10534-2 standard, and the LCA was performed based on the ISO 14040 and ISO 14044 standards. Composite sound absorbing materials subjected to sound absorption coefficient tests showed results in the range of 0.04 to 0.99 and peaking in the frequency range of 800 to 2000 Hz, while airflow resistivity varied between 17.4 and 83.6 kPa⋅s/m². The combination that gave the highest sound absorption coefficient was experimentally found to be PU composite material. Life cycle assessment results revealed that the lowest potential impact on the environment is obtained when composite materials are produced using starch as a binder and its total potential impact on the environment varied between 0.27 and 0.55 Pt, while the highest potential impact was observed by PU composites (0.33 ÷ 0.64 Pt). The results obtained experimentally and by LCA modelling revealed great attractiveness and promising development of composites using WTTF and different binders’ potential for sound absorbing applications.

Since society is moving towards sustainable development, interest in secondary use of waste has recently become significant. This paper investigates a process to develop an acoustic material, using two types of waste. Composite acoustic panels were developed using waste tyre textile fibres (WTTF) and paper sludge (PS), and polyvinyl acetate (PVA) were used as a binder. Non-acoustic (bulk density, airflow resistivity) and acoustic (sound absorption coefficient, sound transmission loss) parameters were studied. Composite acoustic panels with different proportions of WTTF/PS/PVA (sixteen samples) were subjected to testing for the sound absorption coefficient according to ISO 10534-2 and sound transmission loss according to ASTM E2611. The density of all samples varied between 155.2 and 709.9 kg/m³, the thickness between 14.4 and 20.5 mm, and the airflow resistivity between 29.5 and 101.5 kPa∙s/m². The results reveal that the proportion of various waste materials in mixtures can improve the acoustic performance of panels. The combination that gives the highest α_avg. with a value of 0.50 was experimentally found to be 70% WTTF mixed with 15% PVA and 15% H₂O. The average sound absorption coefficient with a value of 0.46 was also found to be 25% WTTF mixed with 25% PS and 25% PVA and 25% H₂O. In sound transmission loss, the most effective was 50% PS and the 50% PVA composite, the TL_eq was 28.3 dB, while the composites together with 30% WTTF, 20% PS and 25% PVA, and 25% H₂O showed 18.9 dB loss. The results obtained using WTTF and/or PS wastes are attractive and show great and promising development potential.

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.

Waste Tyre Textile Fibres (WTTF) are one of the main components of end-of-life tyres. During the recycling process, it is been separated from the rubber and the metal parts. According to the EU Directive on Landfills 1999/31/EC end-of-life tyres may not be accepted by the facility, and it is encouraged to recycle them. Rubber has been successfully recycled and reused for asphalt and playground surfaces production, while metals could be remelted and used again. However, there is a lack of knowledge how to use WTTF. In this research we are proposing WTTF composite material for sound absorption applications. To bind the fibres, polyurethane resin was used. Different percentage by weight of binder was used to determine its’ effect on sound absorption coefficient. The sound absorption coefficient determination method is based on the experimental data based on the ISO 10534-2 standard, and Delany-Bazley-Miki (DBM) acoustic prediction model of fibrous materials, using non-acoustic parameters of the material. The results showed that DBM model accuracy rate varied from 4.9 to 12.7%. Such result indicated that DBM acoustic model has errors in prediction. The aim of this study is to predict the sound absorption coefficient using Delany-Bazley-Miki acoustic model and compare to the experimental study using impedance tube.

Noise pollution has become an increasingly discussed environmental problem in recent years. Developing a traffic infrastructure and recent sustainability goals require new solutions to mitigate noise pollution. This paper investigates the efficiency of the noise barrier made entirely of recycled materials. This solution would help achieve the United Nations sustainable development goals (SDGs). The proposed barrier target SDGs are: Good Health and Well-being (SDG 3); Industry, Innovation, and Infrastructure (SDG 9); Sustainable Cities and Communities (SDG 11); Climate Action (SDG 13). The changed barrier parameters were the parameters of the perforated panel and the air gap behind the porous material. To solve the optimisation problem, the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) method was used. The results showed that the proposed barrier configuration was the following: perforation shape—round, perforation diameter—5 mm, increment angle perforation—30°, thickness of the perforated panel—10 mm, porous absorbing material (composite rubber granule and hemp shive panel (RGHS))—50 mm thick, 20% of hemp shive content, air gap between absorbing material and the rigid backing—100 mm. The total thickness of the noise barrier was 180 mm. The acoustic parameters of the noise barrier structure were: α_avg. = 0.24, peaking at 0.51 (1250 Hz) and R_W = 39.7 ± 1.0 dB. These results indicate that the proposed barrier made of recycled materials could be a sustainable alternative for noise pollution mitigation and improving people’s quality of life.

The use of agricultural waste fibres and natural binders is being investigated as alternatives to synthetic indoor acoustic materials. However, few studies have compared the fibre type, biopolymer type, and fibre-to-binder ratio for both sound absorption and sound transmission within a single controlled composite system. This study investigated the acoustic performance of sugarcane fibre (SF) and coconut fibre (CF) with a fixed thickness of 20 mm and density of 200 kg/m³, mixed with cassava, corn and potato starch binders with fibre–binder ratios from 1:1.0 to 1:0.1. Sound absorption coefficient was measured with an impedance tube, according to ISO 10534-2, and the sound transmission coefficient was determined using a four-microphone impedance tube system, according to ASTM E2611. Porosity was also tested for its relation to acoustic behaviour. The results showed that the coconut fibre composite recorded higher peak absorption, including α = 0.95 for cassava 1:0.6 to 1:0.7 and corn 1:0.6, while sugarcane fibre showed stronger transmission resistance, with SF-CAS-200-1:0.3 decreasing from τ = 0.11 at 160 Hz to 0.02 at 5000 Hz, and SF-PT-200-1:0.4 from τ = 0.10 to 0.03. The highest porosity values were 85.29%, recorded for SC-CAS-200-1:0.1, and 84.13% for CF-CAS-200-1:0.1. Overall, sugarcane fibre composites offered the best balance of absorption and low transmission, indicating strong potential for sustainable indoor acoustic panels, such as ceiling linings and wall systems. Further research should evaluate mechanical strength, fire performance, durability, and moisture resistance to support practical building applications.