Effect of Modified Zinc Oxide-Silica Nanocomposites on Epoxidized Natural Rubber/Tire Waste Composites Properties

Authors

  • Napasorn Kingkohyao
  • Tanit Boonsiri
  • Yeampon Nakaramontri

DOI:

https://doi.org/10.48048/siam.2025.68003

Abstract

Epoxidized natural rubber (ENR) was blended with tire waste (TW) and modified zinc oxide-silica nanoparticles (ZnO-SiO2) using melt mixing, with NR acting as a compatibilizer to link the two incompatible phases—between the polar epoxy groups of ENR and the non-polar rubber in TW. Various ZnO-SiO2 concentrations of 5, 10, 15, and 20 phr were investigated to determine their effects on cure characteristics, mechanical properties, and antibacterial efficiency of the received composites. It was found that adding ZnO-SiO2 improved crosslink density, thereby enhancing the acceleration activity of the chemical crosslinking processes, which resulted in longer cure times and scorch times. Optimal loading of 20 phr enhanced the 100% and 300% moduli values to 1.29 and 3.73 MPa, respectively, along with a tensile strength of 10.52 MPa, highlighting the improved mechanical properties of the nanocomposite with ZnO-SiO2 loadings. This optimal loading also provided superior antibacterial activity, achieving over a 99.0% reduction in bacterial presence within 24 h through releasing Zn2+ ions and generating reactive oxygen species (ROS). At this concentration, the optimal values regarding ZnO-SiO2 particles that can form further agglomerates are reached. These findings support the development of rubber composites with improved performance and durability, as well as enhanced antibacterial protection, for various rubber applications, including footwear, self-pads, and rubber floor mats, highlighting their significance in enhancing product safety and longevity.

 

Keywords: Natural rubber, Epoxidized natural rubber, Tire waste, Nanocomposites, Antibacterial efficiency

Downloads

Published

2025-01-01

Issue

Section

Original Research Articles