高导热环氧纳米复合材料的制备与性能表征

Preparation and Properties of Epoxy Nanocomposites with Excellent Thermal Conductivity

为提高环氧树脂(EP)导热率,文中在树脂基体中复配不同维度的导热填料——"0维"纳米氮化铝(nano-AlN)和"1维"碳纳米管(MCNTs)以期构建三维导热网络。使用N-(β-氨乙基)-γ-氨丙基三甲氧基硅烷偶联剂(KH792)对纳米AlN进行表面改性,并通过酰胺法在H2SO4/HNO3酸化MCNTs表面成功接枝了二乙烯三胺(DETA),提高了无机填料与树脂基体之间的界面相容性,使导热网络的热传递效率大大提高。红外光谱、X射线衍射、拉曼光谱的结果均表明KH792和DETA已分别成功地接枝到纳米AlN和MCNTs表面。扫描电镜显示填料均匀分布在树脂基体中。导热测试证明,添加不同维度填料构建三维导热网络,以及对填料表面进行的有机改性,可以有效提升复合材料的导热率,当混合填料的体积分数(φ)为50%时,复合材料的导热率可提高至2.32 W/(m·K)。

To improve the thermal conductivity of epoxy resin （EP）, thermal conductive fillers with different dimensions were introduced into resin matrix. The ＂zero-dimensional＂ nano aluminum nitride （nano-AlN） and the ＂one-dimensional＂ carbon nanotubes （MCNTs） were added in order to construct three-dimensional thermal networks. Silane coupling agent N-（β-aminoethyl）-γ-aminopropyl trimethoxy silane （KH792） was used to modify the surface of A1N and diethylenetriamine （DETA） was successfully gI：hfted on the surface of H2804/HNO3 treated MCNTs. Therefore, the interface compatibility between the inorganic filler and resin matrix is improved and the heat transfer efficiency d the thermal network is promoted. FT-IR, XRD, Raman results show that KH792 and DETA are successfully grafted on the surface of nanometer A1N and MCNTs. SEM show uniform dispersion of the fillers in resin matrix. Thermal tests show that surface modification and synergistic effect of three dimensional thermal network play a significant role in enhancing the thermal conductivity of composite materials. When the additive amount of hybrid fillers is 50 %, the thermal conductivity d composites increases to 2.32 W/（m·K）.