Preparation and thermal conductivity of dopamine and γ-aminopropyl triethoxysilane co-modified nano-diamond and silicone rubber composites

"Elastomer thermal interface materials were mainly prepared by adding thermal conductive particles to silicone rubber(SiR). Nano-diamond (ND) had high thermal conductivity and insulation properties, making it an ideal thermal conductive filler. Nevertheless, ND was prone to agglomeration and difficult to disperse in SiR. In this work, ND was modified with polydopamine (PDA) and γ-aminopropyl triethoxysilane (KH 550) to improve its dispersion in SiR and its interfacial interaction with. Then the interfacial thermal resistance reduced and the thermal conductivity of the composite improved. Fig 1 showed the infrared spectra of ND, ND-KH 550 and ND-PDA-KH 550. The significant absorption peaks of unmodified ND at 3 200-3 600 cm-1 might be vibration absorption peaks of —OH and H—OH. At 1 624 cm-1, there was a bending vibration absorption peak of —OH or H—OH, indicating the presence of some hydroxyl groups on the ND surface or adsorbed water. The absorption peak position of ND-KH 550 was the same as that of ND, whi