Yang Yang, Wang Ziyu, He Qingqing, Li Xiangjia, Lu Gengxi, Jiang Laiming, Zeng Yushun, Bethers Brandon, Jin Jie, Lin Shuang, Xiao Siqi, Zhu Yizhen, Wu Xianke, Xu Wenwu, Wang Qiming, Chen Yong
Department of Mechanical Engineering, San Diego State University, 5500 Campanile Drive, San Diego, CA 92182, USA.
The Institute of Technological Sciences, Wuhan University, Wuhan 430072, China.
Research (Wash D C). 2022 Jan 27;2022:9840574. doi: 10.34133/2022/9840574. eCollection 2022.
Flame-retardant and thermal management structures have attracted great attention due to the requirement of high-temperature exposure in industrial, aerospace, and thermal power fields, but the development of protective fire-retardant structures with complex shapes to fit arbitrary surfaces is still challenging. Herein, we reported a rotation-blade casting-assisted 3D printing process to fabricate nacre-inspired structures with exceptional mechanical and flame-retardant properties, and the related fundamental mechanisms are studied. 3-(Trimethoxysilyl)propyl methacrylate (TMSPMA) modified boron nitride nanoplatelets (BNs) were aligned by rotation-blade casting during the 3D printing process to build the "brick and mortar" architecture. The 3D printed structures are more lightweight, while having higher fracture toughness than the natural nacre, which is attributed to the crack deflection, aligned BN (a-BNs) bridging, and pull-outs reinforced structures by the covalent bonding between TMSPMA grafted a-BNs and polymer matrix. Thermal conductivity is enhanced by 25.5 times compared with pure polymer and 5.8 times of anisotropy due to the interconnection of a-BNs. 3D printed heat-exchange structures with vertically aligned BNs in complex shapes were demonstrated for efficient thermal control of high-power light-emitting diodes. 3D printed helmet and armor with a-BNs show exceptional mechanical and fire-retardant properties, demonstrating integrated mechanical and thermal protection.
由于工业、航空航天和火电领域对高温暴露的要求，阻燃和热管理结构已引起了极大关注，但开发具有复杂形状以适应任意表面的防护性阻燃结构仍然具有挑战性。在此，我们报道了一种旋转叶片铸造辅助3D打印工艺，用于制造具有优异机械和阻燃性能的仿珍珠层结构，并对相关的基本机制进行了研究。在3D打印过程中，通过旋转叶片铸造使3-(三甲氧基甲硅烷基)丙基甲基丙烯酸酯(TMSPMA)改性的氮化硼纳米片(BNs)排列，以构建“砖和砂浆”结构。3D打印结构更轻，同时具有比天然珍珠层更高的断裂韧性，这归因于裂纹偏转、排列的BN(a-BNs)桥接以及TMSPMA接枝的a-BNs与聚合物基体之间的共价键增强的结构拔出。由于a-BNs的相互连接，与纯聚合物相比，热导率提高了25.5倍，各向异性提高了5.8倍。展示了具有复杂形状的垂直排列BNs的3D打印热交换结构，用于对高功率发光二极管进行高效热控制。带有a-BNs的3D打印头盔和装甲具有优异的机械和阻燃性能，展示了综合的机械和热防护。
