Influence of active, nano, and functionalized zinc oxide particles on the mechanical, cytotoxicity, and thermal stability of carbon black filled SBR/NR blends

Abstract This study examines the viability of functionalized, nano, and active zinc oxide (ZnO) as an alternative activator in styrene butadiene rubber–natural rubber (SBR–NR) blends filled with carbon black. Concerns about the environmental impact and toxicity of Zn leaching into aquatic organisms necessitate reducing the amount of ZnO in rubber compounding. The mechanical properties, crosslink density, and thermal and morphological qualities of the SBR/NR blends made with these ZnO (F2BB, N2BB, and A2BB) were studied and compared to conventional ZnO loaded blend (C5BB). Thermal stability was evaluated using thermogravimetric analysis and temperature scanning stress relaxation. A2BB showed the highest thermal stability, while F2BB exhibited a 35% increase in tensile strength and a 28% increase in elongation at break due to polysulfide linkages. N2BB and A2BB increased tensile strength by 28 and 16% compared to C5BB. Cytotoxicity of various ZnO concentrations on HT‐22 hippocampal cells was investigated, and active and nano ZnO were found to be less toxic. Using active and nano ZnO can improve the mechanical and thermal properties of the blend while reducing environmental toxicity, allowing for a 60% reduction in ZnO concentration in rubber compounds and resulting in cost savings and a sustainable alternative to conventional ZnO.