Shuangshuang Wang, Dianying Feng, He Guan, Yongqiang Guo*, Xia Liu, Chao Yan, Lei Zhang and Junwei Gu*. Highly efficient thermal conductivity of polydimethylsiloxane composites via introducing “Line-Plane”-like hetero-structured fillers. Composites Part A: Applied Science and Manufacturing, 2022, 157: 106911. 2020IF=7.664.（1区材料科学Top期刊）
https://doi.org/10.1016/j.compositesa.2022.106911
Abstract
Graphite oxide (GO) and cetyltrimethylammonium bromide (CTAB) modified multi-walled carbon nanotubes (m-MWCNTs) are utilized to fabricate "Line-Plane"-like hetero-structured thermally conductive GO@MWCNTs fillers by electrostatic self-assembly, which are then introduced into polydimethylsiloxane (PDMS) to fabricate thermally conductive GO@MWCNTs/PDMS composites. When the mass ratio of GO to m-MWCNTs is 2:1, GO@MWCNTs fillers have optimal morphologies and thermal conductivity contribution. When the mass fraction of GO@MWCNTs is 20 wt%, the thermal conductivity coefficient (λ) of GO@MWCNTs/PDMS composites reaches 2.10 W/(m·K), 950% higher than that of pure PDMS (0.20 W/(m·K)), which is also superior to the λ of MWCNTs/PDMS (0.68 W/(m·K)), GO/PDMS (1.59 W/(m·K)) and (GO/MWCNTs)/PDMS (1.28 W/(m·K)) composites with the same amount of single or hybrid thermally conductive fillers. Meantime, the GO@MWCNTs/PDMS composites also present good thermal conduction stability (average λ after 15 heating-cooling cycles in the temperature of 21 to 100oC is 2.14 W/(m·K)) and thermal stability (heat resistance index is 249.3oC).
本文以聚二甲基硅氧烷（PDMS）为基体，以氧化石墨（GO）和十六烷基三甲基溴化铵改性多壁碳纳米管（MWCNTs）静电自组装制备的“线-面”状异质结构GO@MWCNTs为导热填料，经共混复合-浇注成型制备GO@MWCNTs/PDMS导热复合材料。当GO和m-MWCNTs质量比为2：1，GO@MWCNTs导热填料具有最佳的形貌特征和最优的导热贡献力。且当GO@MWCNTs质量分数为20 wt%时，GO@MWCNTs/PDMS导热复合材料的导热系数（λ）为2.10 W/(m·K)，较纯PDMS的λ（0.20 W/(m·K)）提高了950%，也优于相同导热填料用量下的MWCNTs/PDMS（0.68 W/(m·K)）、GO/PDMS（1.59 W/(m·K)）和(GO/MWCNTs)/PDMS（1.28 W/(m·K)）复合材料的λ。此时，GO@MWCNTs/PDMS导热复合材料还具有良好的导热稳定性（21~100℃温度范围15次加热-冷却循环后的λ平均值为2.14 W/(m·K)）和热稳定性。
论文亮点
1. 通过静电自组装法制备“线-面”状异质结构GO@MWCNTs导热填料。当GO和m-MWCNTs质量比为2：1，GO@MWCNTs具有最优的导热贡献力。
2. 当GO@MWCNTs质量分数为20 wt%时，GO@MWCNTs/PDMS导热复合材料的λ为2.10 W/(m·K)，较纯PDMS的λ（0.20 W/(m·K)）提高了950%。
3. GO@MWCNTs/PDMS导热复合材料具有良好的导热稳定性（21~100℃温度范围15次加热-冷却循环后的λ平均值为2.14 W/(m·K)）和热稳定性。