Wang Qiaoli, Li Tianshuo, Ding Yafei, Chen Huibao, Cao Xiyue, Xia Jianfei, Li Baowen, Sun Bin
College of Physics, Qingdao University, Qingdao 266071, P. R. China.
College of Electronics and Information, Qingdao University, Qingdao 266071, P. R. China.
ACS Appl Mater Interfaces. 2022 Sep 14;14(36):41447-41455. doi: 10.1021/acsami.2c12386. Epub 2022 Sep 1.
Thermal management of flexible/stretchable electronics has been a crucial issue. Mass supernumerary thermal heat is created in the repetitive course of deformation because of the large nanocontact resistance between electric conductive fillers, as well as the interfacial resistance between fillers and the polymer matrix. Here, we report a stretchable thermoplastic polyurethane (TPU)-boron nitride nanosheet (BNNS) composite film with a high in-plane thermal conductivity based on an air/water interfacial (AWI) assembly method. In addition to rigid devices, it was capable for thermal management of flexible electronics. During more than 2000 cycles of the bending-releasing process, the average saturated surface temperature of the flexible conductor covered with composite film with 30 wt % BNNSs was approximately 40.8 ± 1 °C (10.5 °C lower than that with pure TPU). Moreover, the thermal dissipating property of the composite under stretching was measured. All the results prove that this TPU-BNNS composite film is a candidate for thermal management of next-generation flexible/stretchable electronics with high power density.
柔性/可拉伸电子器件的热管理一直是一个关键问题。由于导电填料之间存在较大的纳米接触电阻，以及填料与聚合物基体之间的界面电阻，在反复变形过程中会产生大量多余的热。在此，我们基于空气/水界面（AWI）组装方法，报道了一种具有高面内热导率的可拉伸热塑性聚氨酯（TPU）-氮化硼纳米片（BNNS）复合薄膜。除了刚性器件外，它还能够用于柔性电子器件的热管理。在超过2000次的弯曲-释放循环过程中，覆盖有30 wt% BNNSs的复合薄膜的柔性导体的平均饱和表面温度约为40.8±℃（比纯TPU低10.5℃）。此外，还测量了复合材料在拉伸状态下的散热性能。所有结果证明，这种TPU-BNNS复合薄膜是下一代高功率密度柔性/可拉伸电子器件热管理的候选材料。
