Nowadays, the world becomes more contaminated due to various factors such as pollution, global warming and unhealthy human practices. In this review paper, noise pollution is taken into major concern which affects quality of human life. Many researchers had attempted many studies to optimize the sound-absorbing capacity of natural fibers and to replace use of non-biodegradable synthetic sound barriers. This review research also focuses on the measurement of acoustic absorption coefficient (AAC) through various analytical such as Delany–Bazley, Garai–Pompoli and Biot–Allard method and experimental approaches such as impedance tube, reverberation room and environment anonymous (EA) noise. In addition to that, the influence of physical parameters such as fibrous material’s thickness, density and porosity are also reviewed. It was found that most of the reviewer used two microphone impedance test tubes for determining absorption coefficient (α) of natural fiber-reinforced laminates. The more denser, thicker and porous materials shows better absorption rate than less denser, thicker and porous materials due to its high polymerization blending. Finally, these measuring methods are used to enhance the properties such as absorbing and reflecting in applications like sound recording room, acoustic baffles, damping sheets, barrier decoupler, etc.

Camellia Sinensis/Ananas Comosus/GFRP/Epoxy Polymer composites are widely accepted to be a better material for indoor sound damping. It has a series of challenges, like force cuts on the drilling of these composites. The focus is to drill on hybrid laminates by changing the cutting conditions like the speed and feed and the selection of optimum machining process parameters. Nine experimental cycles have been performed, and five various attributes were analyzed, for example, torque, tangential force, thrust force, and also the factor of delamination (Enter & Exit). This study shows a sequential parameter selection for the drilling machining process. Using Multi-attribute optimization, order preference and optimum drilling machining process parameters are selected by the Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS). From the TOPSIS analysis, the best suitable optimum drilling conditions for hybrid laminates are chosen as 600 rpm and 0.02 m/min for cutting speed and feed rate, respectively.

During last few decades, the hybrid composites emerged from natural fiber has brought incontestable advantages over synthetic materials. The environmental impact such as toxicity, nonbiodegradable garbage, and noise pollution has led to the identification of new class of fibers and also subsequent failure in critical stiffness and weight sensitivities of fiber-reinforced polymers has initiated magnification of mechanical toughness. In this present paper, fiber-reinforced composite materials are made with Camellia sinensis–Ananas comosus hybridized by glass fiber and epoxy resin matrix. The amalgamated laminates were forged by a compression molding process with the composition of 40% wt. of reinforcing fiber and 60% wt. of epoxy matrix in a constant proportion. A hydrophilic content present inside natural fibers are alkalized by 5% of NaOH to modify as hydrophobic nature for intensifying bonding between fiber and matrix. These hybridized fibers are mechanically, chemically, morphologically, and acoustically analyzed to meet the requirements of mechanical and sound proofing properties. The results shows that 25% wt. fraction of Camellia sinensis amalgamate with unidirectional fiber shows better average acoustical absorption coefficient (AAC) of 0.46 at 2000–6300 Hz frequency range and compared with existing material to establish the potential of using it in sound-proofing acoustical applications such as architectural acoustics, sound recording and reproduction room, noise barrier walls, loudspeaker design, etc.