In recent years, heat removal has become a crucial issue for electronic packaging devices, along with the development toward high speed and performance. Polymer materials with high thermal conductivity become essential for designing and developing the next generation of electronic packaging devices. However, normally most of the polymers are with relatively low thermal conductivity, ranging from 0.1 to 0.5 W/m-K at room temperature. Various thermally conductive fillers have been embedded into the polymers to improve the polymers’ thermal conductivity. However, a universal method to enhance polymer thermal conductivity through an addition of thermally conductive fillers usually cannot provide an expected value, especially for composites that require electrical insulation.

ZENG Xiaoliang and WANG Fangfang, et al. from Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, have developed a new kind thermal conductive filler -  polymeric composites with silver nanoparticle-deposited boron nitride nanosheets that could effectively enhance the thermal conductivity of polymer, thanks to the bridging connections of silver nanoparticles among boron nitride nanosheets.

The thermal conductivity of the composite filled with the silver nanoparticle-deposited boron nitride nanosheets would be significantly increased from 1.63 W/m-K to 3.06 W/m-K with a loading of 25.1 vol % boron nitride nanosheets, while the electrically insulating properties of the composite still well preserved. Fitting the measured thermal conductivity of epoxy composite with one physical model indicates that the composite with silver nanoparticle-deposited boron nitride nanosheets outperforms the one with boron nitride nanosheets, owning to the lower thermal contact resistance among boron nitride nanosheets’ interfaces. The finding sheds new light on enhancing the thermal conductivity of the polymeric composites which concurrently require the electrical insulation.

The study entitled“Silver Nanoparticle - Deposited Boron Nitride Nanosheets as Fillers for Polymeric Composites with High Thermal Conductivity” was published on Scientific Reports (Nature Publishing Group) in 2016, and recently got included in the list of ESI highly cited papers (SCI cited top 1%), according to the latest statistics from Thomson ESI (Thomson basic scientific index database).

Figure.

A fabrication route for epoxy composites filled with boron nitride nanosheets decorated with silver nanoparticles and their corresponding thermal conductivities.(Image by ZENG Xiaoliang)

Contact: ZENG Xiaoliang

 xl.zeng@siat.ac.cn