Enhanced Thermally Conductive Silicone Grease by Modified Boron Nitride

• Published in: Lubricants 2023-04, Vol.11 (5), p.198
• Main Authors: Wang, Yumeng, Shi, Ning, Liu, Min, Han, Sheng, Yan, Jincan
• Format: Article
• Language: English
• Subjects: Boron nitride; chemical modification; Composite materials; Covalent bonds; Epoxy resins; Fillers; Grafting; Greases; Heat conductivity; Heat resistance; Heat transfer; interfacial thermal resistance; silicone grease; Silicones; Solvents; Spectrum analysis; Thermal conductivity; Thermal properties; Thermal resistance; Van der Waals forces; Viscosity
• ISSN: 2075-4442; 2075-4442
• DOI: 10.3390/lubricants11050198

In this work, a chemical modification method was used to prepare silicone grease with high thermal conductivity. We report two preparation methods for thermal conductive fillers, which are hydroxylated boron nitride-grafted carboxylic silicone oil (h-BN-OH@CS) and amino boron nitride-grafted carboxylic silicone oil (h-BN-NH2@CS). When h-BN-OH@CS and h-BN-NH2@CS were filled with 30 wt% in the base grease, the thermal conductivity was 1.324 W m−1 K−1 and 0.982 W m−1 K−1, which is 6.04 and 4.48 times that of the base grease (0.219 W m−1 K−1), respectively. The interfacial thermal resistance is reduced from 11.699 °C W−1 to 1.889 °C W−1 and 2.514 °C W−1, respectively. Inorganic filler h-BN and organic filler carboxylic silicone oil were chemically grafted to improve the compatibility between h-BN and the base grease. The covalent bond between functionalized h-BN and carboxylic silicone oil is stronger than the van der Waals force, which can reduce the viscosity of the silicone grease.