Unveiling the enhancement of mechanical and tribological properties of Polymer-ZrO2 nanocomposites incorporated agro-waste material

With fluid lubricants to reduce wear of mechanical components during friction, the wear-off of such fluid lubricants has opened a gap for the development of self-lubricating materials, for which polymers have shown good potential. However, there is a need for continuous improvement of the mechanical and wear properties of polymeric materials for advanced applications. In this study, polyester (PE) nanocomposites containing snail shell (SS) particles, as an agro-waste material, and ZrO₂ nanoparticles as a ceramic material were developed to enhance the mechanical and tribological properties of PE. The PE nanocomposites in this study were fabricated by blending and casting. First, the SS particles were hydroxylated using HNO₃ and H₂O₂ to enhance wettability. ZrO₂ and SS particles were mixed at the desired concentrations before introducing them to the PE matrix to ensure good dispersion. Mechanical and tribological responses of the developed PE-ZrO₂/SS nanocomposites were evaluated. From the results obtained, the PE-5wt%ZrO₂/10wt%SS composite sample showed increments in hardness, elastic modulus, and wear resistance of about 128.6%, 149.7%, and 3 orders of magnitude compared to the pure PE and 53%, 57.6%, and 2 orders of magnitude compared to PE-15wt%ZrO₂ composite sample, respectively. The enhancements of the PE-5wt%ZrO₂/10wt%SS composite’s features were linked to the good mechanical properties of ZrO₂, improved stiffness by SS particles, their good load bearing and self-lubrication, and good interfacial interactions of the nanocomposites’ constituents.