Abstract: In the context of sustainable development, considerable interest is being shown in the use of natural fibres as reinforcement in polymer composites and in the development of resins from renewable resources. Natural fibres are widely used for reinforcement in polymer composites. The advantages of natural fibres such as renewable, environmentally friendly, low cost, and many more are well known. Natural fibres are used in many applications such as the aerospace industry, marine sector, automotive industry, sporting segments, and construction industries. This paper focuses on how the presence of water plays a crucial role in the mechanical behavior of natural fibres. Water plays the role of plasticizer. In practice, the major drawbacks of using natural fibre are their high degree of moisture absorption and poor dimensional stability. In this paper, 8 layers and 6 layers of jute and sisal fibre were selected as the reinforcing materials and epoxy resin was chosen as the matrix. The compression molding process was adopted to produce the hybrid composite. Moisture absorption tests were conducted by immersing composite specimens in environmental conditions such as distilled water at room temperature for different time periods like 24hrs, 48hrs, and 72 hrs. The moisture absorption and mechanical properties such as tensile strength, the flexural strength of these composites have been evaluated as per ASTM standards. The process of water absorption of these composites was found to approach Fickian diffusion behaviour. Maximum water uptake values were evaluated; the results revealed that the effect of water absorption showed a significant reduction in the mechanical performance of all composites.

Keywords: Natural fibres, Jute-Sisal-Epoxy Composites, Moisture absorption, Tensile Test, Flexural Test, Impact Test, ILSS Test.

| DOI: 10.17148/IARJSET.2021.81245