Abstract: Polymer coating with high thermal conductivity is of great value in the field of heat dissipation for high-performance electronic devices. In this paper，a UV-curable composite coating was prepared by blending functionalized thermal conductive fillers of different sizes and concentrations with photocurable resin. Firstly，using acrylated cashew phenol as a functional additive，the exfoliation and functionalization of hexagonal boron nitride nanosheets（CBNNS）of different sizes were achieved through mechanical ball milling. Then， two different sizes of CBNNS were used as mixed thermal conductive fillers to prepare UV-curable composite coating. By changing the ratio of different size CBNNS and adjusting the content of mixed fillers，the effects of filler size and content on coating properties were systematically studied. The results showed that when the mass ratio of large and small fillers was 7.5∶2. 5，the thermal conductivity（TC） of the composite coating with a total filling amount of 20% could reach 3. 15 W/（m·K）， and the heat dissipation performance wassignificantly enhanced. The improvement of the thermal conductivity of the composite coatingcould be attributed to the high thermal conductivity of CBNNS，the low interfacial thermal resistance between functionalized fillers and resin matrix，the orientation of large-sized CBNNS，the synergistic effect of mixed fillers and so on.

Key words: boron nitride nanosheets, functionalization, size effect, thermal conductivity, UV-curable coating

摘要： 高导热聚合物涂层在高性能电子器件散热领域具有重要应用价值。通过共混的方式，将不同尺寸、含量的功能化导热填料与光固化树脂复合，制备了可光固化的导热复合涂层。首先，利用丙烯酸化腰果酚作为功能助剂，通过机械球磨，实现不同尺寸六方氮化硼纳米片（CBNNS）的剥离与功能化制备；然后，将 2种尺寸的 CBNNS作为混合导热填料，制备复合光固化涂层。通过改变涂层中大尺寸和小尺寸 CBNNS的比例、调节混合填料的含量，系统研究了填料的尺寸和含量对于涂层性能的影响。结果表明，当大尺寸和小尺寸填料的质量比为 7. 5∶2. 5时，总填充量为 20%的复合涂层的热导率（ TC）可以达到 3. 15 W/（m·K），并表现出显著的散热效果。复合涂层导热性能的提升可归因于 CBNNS的高热导率、功能化填料与树脂基体的低界面热阻、大尺寸 CBNNS的取向、混合填料的协同效应等。

关键词: 氮化硼纳米片, 功能化, 尺寸效应, 导热性, 光固化涂层

CLC Number: 

• TQ637