Krishnamoorthy, K. and Saishanker, V., "Sustainable Polyurethane Composite with Coconut Fiber for NVH Applications," SAE Technical Paper 2016-28-0143, 2016, doi:10.4271/2016-28-0143.
With increasing growth of vehicular population, there is an increasing demand for raw materials. This has added strain to the available resources, which is becoming more and more unsustainable. As a result, search for sustainable materials are continuously happening in our industry and there is a strong focus from everyone to incorporate more and such materials. One way of doing so, is by blending naturally available materials like fibers, with polymers. In this study, naturally available Coconut fibers have been blended successfully with Polyurethane foam, thereby improving the green footprint of the vehicle. Coconut fibers are naturally occurring fiber extracted from the husk of the coconut. Polyurethane foam is the most versatile polymeric foam used in several places of automobile for reducing the Noise, Vibration & Harshness. The composite was manufactured using reaction injection molding technique by reacting polyol with iso-cyanide. The fiber were added to the chemicals before reaction. In this work, various ratio of fibers were added to the PU and were evaluated for basic mechanical properties like tensile strength, elongation, tear strength, dynamic durability and vehicle level tests. The effects of fiber length and fiber content on the physical properties of the composite were also studied. The results were compared with pure PU matrix without the fibers. The test results showed improvement in the physical properties, dynamic properties and accepted NVH behaviour. A ratio was finalized based on the best balance between properties and production feasibility. Subsequently the composite was validated in vehicle, which showed improvement over pure PU foam. Process for bulk production was finalized after production trails.