An Experimental Investigation and Theoretical Modelling for Sound Absorption Performance of Grewia Optiva Fiber Reinforced Composite

In this paper, the Grewia Optiva fibers (GOFs) have been used as reinforcement in two different polymers, i.e., epoxy resin and epoxy-llLannea Coromandelica (LC) resin, and the acoustic properties of GOFs, resins, and their composites have been investigated. Normally, the sound absorption coefficient (SAC) bigger than 0.2 for any material qualifies it as a sound absorbing material. Recently, green or natural materials have been progressively investigated for use in sound absorption for greater environmental sustainability and bio-waste management. The 30 mm-thick samples (pure and composite) have been fabricated and characterized for acoustic properties by an Impedance tube. The SAC of the fabricated samples has been obtained and discussed in detail with reasoning. The SAC of GOFs have been compared with other natural fibers. Similarly, the GOF reinforced composite has been compared with other natural fiber-reinforced composites and concluded that the SAC of composites increase with the increment of the fiber contents. The GOF reinforced epoxy-LC composites have shown higher SAC as compared to other counterparts. Moreover, the SAC of GOF has also been calculated by empirical (Delany-Bazley, Miki, and Garai-Pompoli) and phenomenological (Johnson-Champoux-Allard) models and compared with experimental results. The findings have revealed the possibility of natural resin as a substitute for synthetic resins for a better economic and environmental sustainability.