A novel correlation for predicting the thermal conductivity of heterogeneous nanofiller polymer composites under effects of thermal contact resistance

Abstract

Heterogeneous nanofillers have been regarded as a promising candidate for enhancing the thermal conductivity (TC) of pure polymers. In this study, the effective thermal conductivity (ETC) of polymer composites containing heterogeneous nanofiller is investigated by numerical approach. Many effects of effective parameters are examined, which are the TC ratios between the nanofillers and the matrix (κ1 and κ2), the volume fractions (ϕ1 and ϕ2), and the thermal contact resistance (Rc1 ∗ and Rc2 ∗). Consequently, the ETC depends significantly on a ratio Rc1 ∗/Rc2 ∗ and becomes asymmetrical when their sum Rc1 ∗ + Rc2 ∗ is large, suggesting that to gain higher ETC, Rc1 ∗ should be less than Rc2 ∗ when ϕ1 is greater than ϕ2 and vice versa. Based on the numerical results, a novel correlation for predicting the ETC is proposed as a function of five non-dimensional parameters: ϕ1, ϕ2, κ1, κ2, and Rc ∗. This correlation can be widely utilized for predicting the TC of heterogeneous-nanofiller polymer composites accurately and effectively.