Pornea Arni Gesselle, Dinh Duy Khoe, Hanif Zahid, Yanar Numan, Choi Ki-In, Kwak Min Seok, Kim Jaewoo
R&D Center, Naieel Technology, 6-2 Yuseongdaero 1205, 2nd FL, Daejeon 34104, Republic of Korea.
CMT Co., Ltd., 322 Teheran-ro, Hanshin Intervalley 24 Esat Bldg., Gangnam-gu, Seoul 06211, Republic of Korea.
Nanomaterials (Basel). 2024 May 13;14(10):847. doi: 10.3390/nano14100847.
As one of the emerging nanomaterials, boron nitride nanotubes (BNNTs) provide promising opportunities for diverse applications due to their unique properties, such as high thermal conductivity, immense inertness, and high-temperature durability, while the instability of BNNTs due to their high surface induces agglomerates susceptible to the loss of their advantages. Therefore, the proper functionalization of BNNTs is crucial to highlight their fundamental characteristics. Herein, a simplistic low-cost approach of BNNT surface modification through catechol-polyamine (CAPA) interfacial polymerization is postulated to improve its dispersibility on the polymeric matrix. The modified BNNT was assimilated as a filler additive with AlN/AlO filling materials in a PDMS polymeric matrix to prepare a thermal interface material (TIM). The resulting composite exhibits a heightened isotropic thermal conductivity of 8.10 W/mK, which is a ~47.27% increase compared to pristine composite 5.50 W/mK, and this can be ascribed to the improved BNNT dispersion forming interconnected phonon pathways and the thermal interface resistance reduction due to its augmented compatibility with the polymeric matrix. Moreover, the fabricated composite manifests a fire resistance improvement of ~10% in LOI relative to the neat composite sample, which can be correlated to the thermal stability shift in the TGA and DTA data. An enhancement in thermal permanence is stipulated due to a melting point (Tm) shift of ∼38.5 °C upon the integration of BNNT-CAPA. This improvement can be associated with the good distribution and adhesion of BNNT-CAPA in the polymeric matrix, integrated with its inherent thermal stability, good charring capability, and free radical scavenging effect due to the presence of CAPA on its surface. This study offers new insights into BNNT utilization and its corresponding incorporation into the polymeric matrix, which provides a prospective direction in the preparation of multifunctional materials for electric devices.
作为新兴的纳米材料之一，氮化硼纳米管（BNNTs）因其独特的性能，如高导热性、极大的惰性和高温耐久性，为多种应用提供了广阔的机会，然而，由于其高表面能导致的不稳定性，BNNTs易形成团聚体，从而失去其优势。因此，对BNNTs进行适当的功能化处理对于突出其基本特性至关重要。在此，提出了一种通过儿茶酚 - 多胺（CAPA）界面聚合对BNNTs进行表面改性的简单低成本方法，以提高其在聚合物基体上的分散性。将改性后的BNNT作为填充添加剂与AlN/AlO填充材料在聚二甲基硅氧烷（PDMS）聚合物基体中混合，制备了一种热界面材料（TIM）。所得复合材料表现出增强的各向同性热导率，为8.10 W/mK，与原始复合材料5.50 W/mK相比提高了约47.27%，这可归因于BNNT分散性的改善形成了相互连接的声子通道，以及由于其与聚合物基体的相容性增强而导致的热界面电阻降低。此外，相对于纯复合材料样品，所制备的复合材料在极限氧指数（LOI）方面表现出约10%的耐火性提高，这与热重分析（TGA）和差示热分析（DTA）数据中的热稳定性变化相关。由于BNNT - CAPA的加入，熔点（Tm）发生了约38.5 °C的变化，因此规定热稳定性有所提高。这种改善可与BNNT - CAPA在聚合物基体中的良好分布和粘附性相关联，同时结合其固有的热稳定性、良好的炭化能力以及由于其表面存在CAPA而产生的自由基清除效应。本研究为BNNT的利用及其在聚合物基体中的相应掺入提供了新的见解，为电子器件多功能材料的制备提供了一个有前景的方向。
