Abstract In this study, the atmospheric plasma process (APP) was used to modify the surface of aluminum nitride (AlN) powder with different particle sizes and morphologies (non-spherical and spherical), using modified AlN powder as fillers for polydimethylsiloxane (PDMS) to form AlN/PDMS composites. The functional groups on the surface of the AlN powder, before and after APP modification of the AlN powder, were examined using a Fourier transform infrared spectrometer (FTIR). The thermal conductivity (k) of the sample was measured using a k measurement apparatus that conformed to the ASTM D5470-06 standard. In addition, the k of the sample with the highest k was further increased by the semi-curing technique. Finally, the applicable temperature range of the semi-cured sample was measured by thermogravimetric analysis (TGA). The results show that APP-modified AlN powder can be combined with a C–H functional group to make an APP-modified AlN powder with better adhesion to increase the k of the samples. The filling weight percentage of AlN powder had a nonlinear proportional relationship with k, and the spherical particles enhanced the k of the sample better than the non-spherical particles. The k values of 75 wt% APP-modified non-spherical AlN/PDMS composites and 80 wt% APP-modified spherical AlN/PDMS composites were 1.60 times and 1.48 times higher than unmodified AlN/PDMS composites, respectively. Semi-cured 80 wt% APP-modified spherical AlN/PDMS composites had a k of 4.19 W/mK and an enhancement of 1.4 times that compared with fully cured composites. Furthermore, semi-cured 80 wt% APP-modified spherical AlN/PDMS worked safely within the range of 200 °C and had a superior k.

中文翻译：

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使用大气等离子体改性技术增强 AlN/PDMS 复合材料的热导率

摘要 本研究采用常压等离子体工艺 (APP) 对不同粒径和形貌 (非球形和球形) 的氮化铝 (AlN) 粉末进行表面改性, 使用改性的 AlN 粉末作为聚二甲基硅氧烷 (PDMS) 的填料。形成 AlN/PDMS 复合材料。使用傅里叶变换红外光谱仪 (FTIR) 检测了 AlN 粉末在 APP 改性前后 AlN 粉末表面的官能团。使用符合 ASTM D5470-06 标准的 k 测量装置测量样品的热导率 (k)。此外，通过半固化技术进一步提高了具有最高 k 的样品的 k。最后，通过热重分析（TGA）测量半固化样品的适用温度范围。结果表明，APP改性的AlN粉末可以与C-H官能团结合，使APP改性的AlN粉末具有更好的附着力，从而提高样品的k值。AlN粉末的填充重量百分比与k呈非线性比例关系，球形颗粒比非球形颗粒更好地提高了样品的k。75 wt% APP 改性非球形AlN/PDMS 复合材料和80 wt% APP 改性球形AlN/PDMS 复合材料的k 值分别比未改性AlN/PDMS 复合材料高1.60 倍和1.48 倍。半固化的 80 wt% APP 改性球形 AlN/PDMS 复合材料的 ak 为 4.19 W/mK，与完全固化的复合材料相比提高了 1.4 倍。此外，