Reducing Interfacial Thermal Resistance Between Epoxy and Alumina via Interfacial Engineering

Epoxy composites are increasingly employed in the information industry fields, where the interfacial thermal resistance of polymer/nanofiller is considered to be one of the most important factors affecting the thermal conductivity of polymer composites. Herein, the interfacial thermal resistance with different functionalized aluminas and epoxy is first investigated by molecular dynamics. The functional groups considered in aluminas are –OH, butyltrimethoxysilane terminating with –CH3, and aminopropyltriethoxysilane terminating with –NH2. The results indicate that aminopropyltriethoxysilane terminating with –NH2 has the best effect on reducing the interfacial thermal resistance up to 66.67%. The mechanism of interfacial thermal resistance reduction is analyzed through vibrational density of state and overlapping energy, and then the effect of functionalization on interfacial heat transfer is intuitively demonstrated through local thermal analysis. The most effective reduction of the thermal resistance is attributable to the functional groups containing the same group end group as epoxy and the moderate chain length, which can reduce the vibrational mismatch and form more effective heat conduction channels to enhance the thermal transport efficiency in the nanocomposite. This work can shed some light on designing and fabricating thermally conductive inorganic/polymer composite. Interfacial thermal resistance is one of the main factors limiting the improvement of the thermal conductivity of epoxy composites. Herein, the interfacial heat transfer between different functionalized alumina and epoxy is simulated by the molecular dynamics method, and it is found that functionalization can effectively reduce interfacial thermal resistance, which provides guidance for the heat transfer enhancement of epoxy composites.