Physical and Mechanical Properties of Nitrile Butadiene Rubber Modified by Single-Walled Carbon Nanotube Concentrates

Single-walled carbon nanotubes (SWCNTs) are used as a universal additive to increase the mechanical and electrical properties of materials. In this work, we introduced SWCNTs in nitrile butadiene rubbers filled with 60 phr carbon black using concentrates of predispersed SWCNTs in a solution of nitrile butadiene rubber with dibutyl phthalate. It is shown that the addition of 0.15 wt % of SWCNTs allowed decreasing the specific volume electrical resistivity by four orders from 2.3 × 10⁶ to 7.9 × 10² Ω cm and increasing the tensile moduli at 50% and 100% elongation by 50% and 30%, respectively. The tensile moduli at 50% and 100% elongation and the tear resistance linearly depend on the concentration of SWCNTs in the nanocomposite for the studied concentration range up to 0.5 wt %, while the elongation at break and the tensile strength of the rubber do not change within the tolerance of measurements. The specific volume electrical resistivity depends on the concentration of SWCNTs in the rubber according to Kirkpatrick power law with a percolation threshold of 0.05 wt % and achieves 10 Ω cm at 0.5 wt % of SWCNTs.