Enhanced damping and thermal conductivity of hBN/silicone rubber composites via strong interfacial action

Abstract

High integration and miniaturization of electronic systems require thermal conductivity and mechanical damping materials. In this work, hexagonal boron nitride (hBN) particles were modified by vinyltrimethoxysilane (V171) and hexadecyltrimethoxysilane (N3116) for comparing, and described as V171-hBN and N3116-hBN, respectively. The pristine and surface modified hBN were filled in vinylmethylpolysiloxane (VMQ), and then vulcanized to fabricate hBN/silicone rubber composites. The damping properties of V171-hBN/silicone rubber composites were considerably higher than that of pristine hBN/silicone rubber composites, while for N3116-hBN/silicone rubber composites were in contrast. The strong interfacial action in V171-hBN/silicone rubber composites came from the chemical bond by vinyl groups on the surface of V171-hBN taking part in the vulcanization of VMQ. This strong interfacial action led the deformation of hBN, and the internal friction between layers of hBN significantly increased to dissipate more energy. As a result, V171-hBN/silicone rubber composites with excellent damping and thermal conductivity as well as good mechanical properties were obtained.