where σ0, ρo, t, 𝜑, and 𝜑c represent the intrinsic conductivity of the fillers, the resistivity coefficient, the exponent, the volume fraction of conductive particles, and percolation transition, respectively. The exponent t depends on the dimensionality of the polymers, which is called universal percolation behavior. Based on the theoretical calculation, it equals 1-1.3 and 2 for two-dimensional (2D) networks and a three-dimensional (3D) network.