In recent days, with the shift of the car industry to Electric Vehicles (EVs), managing Noise, Vibration, and Harshness (NVH) has become a major challenge. This paper focuses on a comparative study of polyurethane (PU) foam with eco-friendly alternatives such as flax, jute, and recycled rubber. The study differentiates the materials based on damping ratios and peak absorption, as well as other non-acoustic factors useful in automotive applications. It also discusses current usage by some major automakers. Experimental results show that these materials are viable options, though a significant gap remains regarding long-term durability. Lastly, future trends show the hybridization of these materials to cope with industrial standards.

Natural and recycled materials are great for making cars quieter and greener. Studies prove they can block sound just as well as old plastics. Sheep wool and flax are excellent for airborne noise, and recycled rubber is highly effective in stopping heavy vibrations. Using these materials massively lowers a car’s carbon footprint. However, natural fibers still need chemical treatments to prevent them from catching fire and growing Mold. The main “Research Gap” is that scientists still need to perform long-term aging studies to see how these natural parts survive over a full 15-year car lifespan.

[1]O. Unruh, B. Fuhrmann, and H. Obst, “Performance Evaluation of Various Structural Damping Materials for Application in Electric Vehicles,” SAE Technical Paper, No. 2021-01-1124, Aug. 2021. [2]M. Ouda et al., “A Comprehensive Review of Sustainable Thermal and Acoustic Insulation Materials from Various Waste Sources,” Buildings, vol. 15, no. 16, p. 2876, 2025. [3]H. Shah, “What is Automotive Noise, Vibration, and Harshness (NVH?),” Ansys Blog, Apr. 13, 2023. [4]N. de Beus and M. Carus, “Carbon Footprint and Sustainability of Different Natural Fibres for Bio composites and Insulation Material,” nova-Institute, Mar. 2019. [5]M. Szczepański and A. Manguri, “Recycling Paper Waste into Structural Cellulose Composites: Mechanical and Thermal Insights,” OSF Preprints, Nov. 2025. [6]”Fiber Type and Chemical Composition of Jute, Hemp, Ramie, and Kenaf,” PMC, Article ID PMC10837508, 2024. [7]”Bast Fiber Properties and Wax Content,” Polymers, DOI: 10.1002/PLS2.10167. [8]A. E. Tiuc et al., “Improved Sound Absorption Properties of Sheep Wool,” Materials, PMC7040890, 2020. [9]F. Asdrubali, S. Schiavoni, and K. V. Horoshenkov, “A Review of Sustainable Materials for Acoustic Applications,” Building Acoustics, vol. 19, pp. 283-312, 2012. [10]Standard Test Method for Measuring Vibration-Damping Properties of Materials, ASTM E756-05(2014), ASTM International, West Conshohocken, PA, 2014. [11]”Effect of Fiber Content on Sound Absorption Properties,” PMC, Article ID PMC11263662, 2024. [12]”Acoustic properties of recycled rubber crumb,” MDPI Materials, vol. 18, p. 3144, 2025. [13]”Damping of Structure-borne Noise in Automobiles,” Sika Automotive Technical Report. [14] A. Mittermiller, “Hydrin DP5245 elastomer for vibration damping,” Rubber & Plastics News, May 2021. [15]”High-viscosity and High-elastic Modified Bitumen,” MDPI Sustainability, vol. 15, p. 14089, 2023. [16]”Influence of Temperature on the Damping Properties of Selected Viscoelastic Materials,” J. Vib. Control, 2025. [17]Y. X. Thong et al., “How to Compare and Select Flame Retardants for Rigid Polyurethane Foam,” J. Nanotechnol. Nanomaterials, vol. 3, no. 2, pp. 61-66, 2022. [18]Tests for Flammability of Plastic Materials for Parts in Devices and Appliances, UL 94, Underwriters Laboratories Inc., Northbrook, IL, 2023. [19]”UL 94 Flame Ratings: What You Need to Know,” Rogers Corporation, 2025. [20]”Water absorption behaviour of jute epoxy composites,” MJCsm, 2023. [21]”Effect of Hemp Fiber Surface Treatment on the Moisture/Water Resistance… of Reinforced PLA Composites,” Materials, vol. 14, p. 4332, 2021. [22]”Jute, World Verified Carbon Footprint,” Carbon Cloud, 2024. [23]”BMW Group achieves major breakthrough with utilization of natural fiber composites,” BMW Group Press, 2025. [24]”Development Process… Biodegradability of Jute Fiber/PLA Fiber Composites for Automotive Headlining,” SAE Technical Paper 2011-28-0007. [25]G. Biastoch, E. Kraft, F. Khan, et al., “Testing the Biodegradability of Jute to Improve End-of-Life Cycle Assessment,” Bauhaus-Universität Weimar, 2025. [26]”Sustainable Soundproofing Materials,” Lindenwood Univ, 2023. [27]P. Sature and A. Mache, “Mechanical characterization and water absorption studies on jute/hemp reinforced hybrid composites,” American Journal of Materials Science, vol. 5, no. 3C, pp. 133–139, 2015. [28]”Natural fiber recycled plastic hybrids in automotive,” PMC, Article ID PMC9414523. [29]”Conserving resources through innovative recycled materials,” Mercedes-Benz Group, 2025. [30]”Ford continues use of natural fibers,” TriplePundit, 2016.

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