Construction and mechanism of 3D printed polyamide 12/boron nitride template composites with localized and unidirectional thermally conductive property

Aiming at dissipating the undesired heat generated by the electronic devises during working process to the outside through a controllable way without affecting other adjacent components, novel polyamide 12 (PA12) based template composites with selectively distributed boron nitride (BN) have been explored successfully by simple and effective 3D printing technology coupled with roller-rolling method. The morphological structure, thermally conductive property as well as thermally conductive mechanism of the template composite were investigated systematically. The improved template composites showed significant localized and unidirectional thermally conductive property. And the through-plane thermal conductivity of the template composite can reach as high as 4.26 W/(m·K) with the BN content of 33.5 wt%, which is over 3 times that of the isotropic composite with the same BN content. Both of the experiment and simulated results revealed that the significantly enhanced thermally conductive property for the composites was attributed to the selectively distributed BN, which is beneficial to realize precise and controllable heat dissipation. This study sheds light on the rational design and fabrication of the high-efficiency composites with localized and unidirectional thermally conductive property for the application of thermal management system of the high-frequency and high-speed electronic devices.