The creation of tenable green composites is in high demand, due to ecologically available resources paving the way for applications to thrive in the manufacturing, aerospace, structural, and maritime industries. Hence, it is vital to understand the performance characteristics of natural fiber-reinforced polymer composites. The elastic constants of coir fiber powder-reinforced plasticized polyvinyl chloride composite are determined using impulsive excitation vibration in this study. The optimization study on the elastic constants was carried out using Box–Behnken experimental design, based on response surface methodology, having three factors of fiber content (wt.%), fiber size (μm) and chemical treatments. The results were evaluated using analysis of variance and regression analysis. Additionally, experimental and optimized results were compared, leading to error analysis. Young’s modulus of 18.2 MPa and shear modulus of 6.6 MPa were obtained for a combination of fiber content (2 wt%), fiber size (225 μm), and triethoxy (ethyl) silane treatment, which is suitable for various electrical, automotive, etc., applications.

PVC (polyvinyl chloride) is a tough polymer used in applications, including plumbing and construction materials. As natural fibre-reinforced composites have more advantages over conventional synthetic composites, this paper focuses on the fatigue analysis of PVC composite which is reinforced with coir fibre. The influences of three input parameters, namely, the size of the coir fibre, coir fibre content, and the chemicals that are used in the treatment of coir fibre on the fatigue life of the composite are examined. In the response surface model (RSM), Box-Behnken designs (BBD) are employed for the preparation/analysis/optimization of the samples. ANSYS software is used to perform the fatigue analysis of different samples containing various combinations of the parameters. To determine the effects of various input parameters on the fatigue behaviour of composites, ANOVA is employed to determine their optimal levels. Regression equations are established to determine the fatigue limit. When treated with triethoxy(ethyl)silane, coir with a concentration of 6wt. and a particle size of 75μm exhibits a maximum fatigue limit of 2.819MPa.