Effect of Hydrophobic Silica Particles on Mechanical Properties of Bromobutyl Rubber (BIIR)

Abstract

Abstract Silica is one of the most important reinforcing fillers in the rubber industry. As an excellent reinforcing agent, it can endow rubber with higher tensile strength, elongation at break, elasticity, heat resistance, tear strength, etc., and is widely used in rubber products. BIIR has good air tightness, fatigue resistance, aging resistance, chemical resistance, and good processing performance, so it is widely used in tires and other industries. In this paper, three hydrophobic nano-powder materials, silica airgel, hydrophobic fumed silica and hydrophobic precipitated silica, were added to BIIR during rubber mixing and vulcanization. The effects of three nano-powder materials on the physical and mechanical properties of BIIR were compared. The results show that all three hydrophobic silica nano-powder materials can effectively improve the mechanical properties of BIIR, among which silica airgel has the most significant enhancement effect on the mechanical properties of BIIR. The tensile strength of 40% airgel-reinforced vulcanized rubber can be increased from 2.42MPa to 5.84MPa. The 100% constant tensile stress can be increased from 0.34MPa to 1.04MPa, while the tear strength is high (19.07N/mm), the hardness is extremely high (89HA), and the thermal conductivity is as low as 0.13439 (W/m·K).