International Journal of Applied Science and Engineering https://doi.org/10.6703/IJASE.202209_19(3).004 Vol.19(3) 2021317 OPEN ACCESS Received: August 11, 2021 Revised: March 18, 2022 Accepted: June 27, 2022 Corresponding Author: Omolayo M. Ikumapayi ikumapayi.omolayo@abuad.edu. ng Copyright: The Author(s). This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted distribution provided the original author and source are cited. Publisher: Chaoyang University of Technology ISSN: 1727-2394 (Print) ISSN: 1727-7841 (Online) Effect of particle size and weight percentage variation on the mechanical properties of periwinkle shell reinforced polymer (epoxy resin) matrix composite Mfon Udo 1 , Sunday A. Afolalu 2 , Omolayo M. Ikumapayi 2* , Philip Babalola 1 , Victoria Obasa 3 , Oluseyum Akpalikpo 3 1 Department of Mechanical Engineering, Covenant University, Ota, 112212, Nigeria 2 Department of Mechanical Engineering, Afe Babalola University, Ado Ekiti, 360101, Nigeria 3 Department of Metallurgical and Materials Engineering, University of Lagos, 101017, Nigeria ABSTRACT Polymers are very interesting and useful materials that have many applications in various areas of engineering. Composites formed with these materials are known to exhibit outstanding mechanical, electrical, and thermal properties. In this work, a polymer, epoxy resin, was reinforced with a biodegradable material, periwinkle shell (PWS) particles, using the hand lay-up method. The PWS was pulverized using a ball mill and three sieve sizes of the PWS (75, 150, and 300 µm) were sieved out. Various samples of the composite were produced by reinforcing the epoxy resin matrix with 10, 20, 30, 40, and 50 wt% of each of the PWS particle sieve sizes. The samples so formed were subjected to the following mechanical tests: hardness, tensile, compressive, and impact tests. It was found out that the samples of composites showed higher values of the parameters tested for than ordinary epoxy resin showed. In the samples of composites, it was found that the samples with a higher weight percentage of the PWS reinforcement recorded higher values of those mechanical properties tested for. The higher the weight percentage of the PWS in the composite, the greater the value of the mechanical property tested for. Keywords: Composites, Epoxy resin, Periwinkle shell, Mechanical properties. 1. INTRODUCTION In recent times composite making has become a major method of developing new materials with superior quality for service in various areas of engineering. The application of composite materials can be seen in construction, civil, electrical, automobile, aeronautics, and mechanical engineering. Generally, a composite is a material made from two or more materials with distinctly different properties but amalgamated and engineered to have specific superior properties different from those of the constituent materials (Mishra et al., 2002; Landesmann et al., 2015). In a composite material, one of the constituent materials will necessarily be in a continuous phase known as the matrix while the other constituent is in a discontinuous phase known as the reinforcement. While the matrix is relatively softer and accommodates the reinforcement phase and shares the applied load with it, the reinforcement is harder and majorly carries the applied load to the composite. Many authors have shown that composite forming leads to the improvement of various mechanical, electrical, thermal, and corrosion resistance properties of the material being reinforced (Iyasele, 2018; Ofem and Umar, 2012; Loto and Udo, 2019; Singh et al., 2020; Rajak et al., 2019; Babalola et al, 2015).