Effective natural rubber vulcanization using electron beam irradiation and DFT driven cross-linking agents

Abstract

This study explores an eco-friendly and efficient method for vulcanizing natural rubber latex using electron beam irradiation, enhanced by cross-linking agents. Unlike conventional sulfur vulcanization, electron beam vulcanization can occur at room temperature, reducing the need for chemical additives and eliminating toxic waste. Both experimental and theoretical studies were performed to evaluate vulcanization efficiency, utilizing ethylene glycol dimethacrylate (EDMA) and 1,6-hexanediol diacrylate (HDDA) as cross-linking agents. Electron beam irradiation is an effective method for generating reactive radical species via homolytic cleavage of covalent bonds in natural rubber. Quantum mechanical calculations, including density functional theory (DFT) and transition state searches using linear and quadratic synchronous transit methods, were employed to examine molecular structures, energies, and reaction pathways in the vulcanization process. The findings reveal that HDDA demonstrates superior cross-linking performance compared to EDMA, making it the preferred choice for enhancing vulcanization efficiency. These results offer valuable insights for optimizing rubber manufacturing processes, potentially improving the quality and efficiency of industrial rubber production.