Ningbo Materials has made progress in the preparation of high thermal conductivity epoxy composite materials

The continuous improvement of the functionality, integration and power density of advanced electronic devices of the third generation semiconductor materials will inevitably lead to a high concentration of waste heat generated by the operation of the device. Electronic packaging materials are the key to thermal management of electronic devices, and the thermal conductivity of epoxy electronic packaging materials used at present can not meet the development needs of advanced semiconductor materials. Since its discovery, graphene has attracted much attention for its excellent physical properties, and its ultra-high thermal conductivity (up to 5300W/mK) and large surface area make it easy to build effective thermal conduction paths, making it an ideal fillerto enhance the thermal conductivity of polymer substyl materials. The preparation of graphene 3D structure is an effective method to improve the thermal conductivity of composite materials. Currently commonly used methods include chemical vapor deposition and ice template method, but these methods are more expensive to prepare and difficult to obtain high graphene content, so it is still a challenge to greatly improve the thermal conductivity of resin substrates.
Based on the above questions, the functional carbon materials team of the Surface Division of the Ningbo Institute of Materials Technology and Engineering of the Chinese Academy of Sciences uses low-cost commercial polyurethane foam as a template, coats graphene nano-sheets on its surface bread and removes the polyurethane template with rapid heating to obtain a fully structured 3D graphene foam. As shown in Figure 1,
at 6.8wt% graphene content, the thermal conductivity of epoxy composites reached 8.04W/mK, which is 44 times higher than pure epoxy resins, while maintaining good technical properties.
work has been published in core journals in the field of nanomaterials (Nanoscale, 2019, 11, 17600-17606) and featured in cover articles.
in addition, the study also found that the introduction of micron-scale spherical alumina particles in the graphene filtration process, graphene sheet orientation from the horizontal direction to the vertical direction, to obtain a similar "pea pod" structure. This type of binary graphene-alumina filler, which mimics the structure of pea pods, can effectively enhance the thermal conductivity of polymer materials, and the longitudinal and horizontal thermal conductivity of epoxy composites prepared by this method can reach 13.3W/mK and 33.4W/mK( as shown in Figure 2), respectively, and will be published in the core journal Chem. Eng. J., 2020, 381, 122690), a highly thermally conductive epoxy composite material developed to replace traditional polymer materials to solve the thermal problems of today's highly integrated electronic devices.
more than this work has been supported by projects such as the National Natural Science Foundation of China (51573201), the Zhejiang Public Interest Technology Application Research Program (2016C31026) and the 3315 Innovation Team.
Figure 1 (a

) The relationship between the thermal conductivity of epoxy composites and graphene content;