Waste Rubber-Polyethylene Composite Materials for Enhancement of Mechanical, Thermal, and Electrical Properties–A Critical Review

Scholars have redirected their attention toward the use of recycled resources as a response to the escalating environmental concerns. They demonstrated that recycled materials are essential for sustainable practices, as they contribute to environmental conservation and the effective use of resources, through the examination of their impact on waste reduction, energy saving, and the alleviation of greenhouse gas emissions. Furthermore, recycling has substantial economic and social ramifications, and rubber is one of the materials that may undergo the recycling process. Considering the significance of recycled rubber in addressing environmental issues, including excessive waste in landfills and resource depletion, it is essential to examine the process of transforming waste rubber into valuable commodities through recycling. The many uses of recycled rubber range from eco-friendly construction materials to inventive consumer goods, with a focus on its contribution to fostering a sustainable, closed-loop economy. Waste tires are a significant kind of waste rubber. Hence, the process of recycling used tires and transforming them into valuable commodities has significant ecological and financial significance. This paper reviews the reuse of scrap tires to mitigate environmental hazards. It analyzes the effect of using recycled rubber on the mechanical and physical properties of low and high-density polyethylene. It shows that the distribution of recycled rubber granules in polyethylene increases its density with improved thermal conductivity values due to the presence of carbon black. The study also shows a deterioration in the mechanical properties of polyethylene. Tensile strength, flexural strength, and hardness are examples; however, the inclusion of tire waste particles improves impact strength ratings. Nonetheless, this deterioration stays within permissible boundaries when evaluating the economic and environmental advantages it offers.