Experimental Investigation of Coconut Coir Ash and Rice Husk Composites

Abstract

Natural fibers and fillers from renewable resources are emerging as sustainable alternatives to synthetic materials in polymer composites. This study focuses on developing hybrid composites using coconut coir ash as the filler and rice husk as the fiber, with epoxy resin as the matrix. The research investigates the mechanical behavior of the hybrid composites, particularly under impact, flexural, tensile, compression, and hardness loads. Test results indicate that these hybrid composites outperform conventional single glass fiber- reinforced composites. The findings highlight the potential of natural hybrid reinforcements for eco-friendly and high- performance composite applications.

Introduction

The increasing demand for sustainable and eco-friendly materials has prompted research into natural fiber-reinforced polymer composites. This study explores the use of Coconut Coir Ash (CCA) and Rice Husk (RH) as reinforcements in epoxy-based hybrid composites to replace traditional synthetic materials. The aim is to improve mechanical, thermal, and damping properties while promoting environmental sustainability and cost-effectiveness.

Problem Statement

Synthetic fibers, though mechanically strong, are non-renewable and polluting. This research aims to develop a lightweight, durable, and thermally stable composite using CCA (as filler) and RH (as fiber) in an epoxy matrix, addressing key challenges such as fiber-matrix bonding, thermal stability, and resistance to environmental conditions.

Objectives

1. Composite Development: Fabricate hybrid composites with varied CCA and RH content using the Hand Lay-Up and Compression Molding methods.

2. Mechanical Enhancement: Improve tensile, compressive, shear, and impact properties.

3. Thermal and Damping Analysis: Assess heat resistance, vibration damping, and thermal conductivity.

4. Eco-Friendliness: Promote the use of agricultural waste and reduce reliance on synthetic fibers.

5. Industrial Application: Evaluate suitability for automotive, aerospace, and construction sectors.

6. Performance Optimization: Compare with traditional composites (e.g., glass fiber) and optimize material ratios for strength and weight.

Literature Review

Prior studies have shown the potential of natural fibers like jute and banana in improving the mechanical and thermal properties of composites. These works support the feasibility of hybrid reinforcements using agricultural waste for structural applications.

Methodology

• Materials Used: Rice Husk (fiber), Coconut Coir Ash (filler), Epoxy Resin (matrix), and Hardener.

• Preparation: Cleaning, drying, grinding, and sieving of RH and CCA. Epoxy and hardener mixed in a 10:1 ratio.

• Fabrication Process:

  • Hand lay-up and compression molding techniques applied.

  • Layered composite cured at room and elevated temperatures.

• Specimen Preparation: Cured composites are removed from molds and cut into test specimens for evaluation.

Conclusion

The experimental study successfully demonstrated the potential of hybrid composites using Coconut Coir Ash and Rice Husk with epoxy resin.Mechanical tests revealed notable improvements in tensile, compressive, impact, and shear strengths.The composite exhibited excellent interfacial bonding and structural integrity.Its lightweight nature combined with high strength makes it ideal for industrial applications.Natural fillers proved to be cost-effective and environmentally sustainable alternatives to synthetic fibers.SEM analysis confirmed uniform dispersion and minimal voids in the composite matrix.The hardness results indicated good surface resistance suitable for structural use.These composites are highly suitable for applications in aerospace, automotive, and construction sectors.The study supports the use of agricultural waste in developing high- performance green materials.Future research may focus on fiber treatments and thermal behavior for broader applications.

References

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Copyright

Copyright © 2025 Arun Kumar D, Mooventhan P, Nithish R, Emayavendhan A, Mr. K. Vijayarajan. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.