Influence of critical carbon nanotube loading on mechanical and electrical properties of epoxidized natural rubber nanocomposites

Nanocomposites based on carbon nanotube (CNT) filled epoxidized natural rubber (ENR) were prepared by melt mixing method with the main aim to elucidate the critical CNT loading that provides optimal mechanical and electrical properties. The reinforcing effect of CNT in ENR matrix was assessed from torque difference (MH-ML) and 100% moduli that increased with CNT loading. Furthermore, dielectric constant and electrical conductivity increased with CNT loading. In addition, the percolation threshold concentration was about 2.3 phr of CNT with the t-value of fundamental percolation theory at 1.74. This indicates three dimensional (3D) CNT networks dispersed in the ENR matrix. In addition, the dipole-dipole interactions of ENR and CNT increased the polarization effect that caused formation of conductive material with micro-capacitor characteristics.