Investigation of Compositional Effects of Virgin and Recycled HDPE on Mechanical Properties of Pipe

¹ Department of Mechanical Engineering, Debre Tabor University, Debre Tabor, Ethiopia.
² Department of Mechanical Engineering Science, University of Johannesburg, Johannesburg., South Africa.
³ Department of Mechanical Engineering, Bahir Dar Institute of Technology, Bahir Dar University, Bahir Dar, Ethiopia.
⁴ Pan African University for Life and Earth Sciences Institute (PAULESI), Ibadan, Nigeria

^* Corresponding author: proffatobasameni@gmail.com

Abstract

Nowadays, High-Density Polyethylene (HDPE) polymers are widely being used and its products are preferable than metals having the properties such as lightweight, ease of manufacture, stronger and tough. This makes HDPE polymers as the top choice by manufacturers. However, one of the drawbacks is that this polymer takes time to decay and affects the environment when this material is disposed as wastes. Almost all industries use only virgin imported materials to produce HDPE pipe and fittings, and this leads to increase in manufacturing cost and extraction of virgin material. The aim of this research is to overcome this problem by recycling process. This research work focuses on investigating the compositional effects of virgin and recycled HDPE on the mechanical properties of HDPE pipe fitting. The mixing of recycled with virgin (pure) HDPE were done at different weight percentages (0:100, 10:90, 20:80, 30:70, 40:60, 50:50, 60:40, 70:30, 80:20, 90:10, and 100:0). In this work, 16.5 kg virgin HDPE were used, and 16.5 kg recycled HDPE pellets were prepared. Also, 11 (eleven) T-reducer pipe fitting samples were produced via injection moulding machine. Melt flow rate and ash content of the manufactured recycled materials were tested to determine the quality of the plastics. Tensile strength test was also conducted to investigate the mechanical property in order to determine the percentage which possess the optimum strength. From the experimental results, recycled contents up to 70 wt. % and virgin contents up to 30 wt. % by mass were found to meet the standard requirements. This optimum proportion will help AG Pipe fitting company to save a lot in dollars every year by using the scrap contents.