Xiao Zhong, Mukun He, Chenyang Zhang, Yongqiang Guo*, Jinwen Hu and Junwei Gu*. Heterostructured BN@Co-C@C Endowing Polyester Composites Excellent Thermal Conductivity and Microwave Absorption at C Band. Advanced Functional Materials, 2024, 10.1002/adfm.202313544. 2022IF=19.0.（1區材料科學Top期刊）https://doi.org/10.1002/adfm.202313544
Abstract
The trends of miniaturization, lightweight, and high integration in electronics have brought serious issues in heat dissipation and electromagnetic compatibility, and also limited the simultaneous use of thermally conductive & microwave absorption materials. Therefore, it is imperative to design materials that possess those dual functions. In this work, one-pot method is used to anchor zeolitic imidazolate framework ZIF-67 coated with polydopamine (PDA) on boron nitride (BN) to obtain BN@ZIF-67@PDA. The pyrolysis product BN@Co-C@C is used as heterostructured thermally conductive/microwave absorption fillers and blended with polyethylene terephthalate (PET) to prepare BN@Co-C@C/PET composites. When the mass ratio of BN to ZIF-67@PDA is 7.5:1 and the mass fraction of BN7.5@Co-C@C is 45 wt%, the BN7.5@Co-C@C/PET composites exhibit excellent thermal conductivities and microwave absorption performances. The thermal conductivity coefficient is 5.37 W m-1 K-1, which is 35.8 times higher than that of PET (0.15 W m-1 K-1), and also higher than that of 45 wt% (BN7.5/Co-C@C)/PET composites (4.03 W m-1 K-1) prepared by directly mixing. The minimum reflection loss of 45 wt% BN7.5@Co-C@C/PET composites is -63.1 dB at 4.72 GHz, and corresponding effective absorption bandwidth is 1.28 GHz (4.08~5.36 GHz), achieving excellent microwave absorption performance at C band.電子產品的小型化、輕薄化和高度集成化等發展趨勢帶來了愈發嚴重的散熱和電磁兼容問題，而其狹窄的內部空間難以支持導熱材料和吸波材料的疊加使用，設計制備兼具導熱/吸波雙功能材料勢在必行。本文采用一鍋法并結合“正向沉積-逆向生長”機制將聚多巴胺（PDA）包覆的沸石咪唑酯骨架ZIF-67分散錨定于BN（BN@ZIF-67@PDA）表面，并將其熱解產物BN@Co-C@C作為異質結構導熱/吸波功能填料與聚對苯二甲酸乙二醇酯（PET）共混制備BN@Co-C@C/PET復合材料。當BN與ZIF-67@PDA的質量比為7.5:1且BN7.5@Co-C@C的質量分數為45 wt%時，BN7.5@Co-C@C/PET復合材料兼具出色的導熱和吸波性能，其導熱系數（λ）達到5.37 W/(m·K)，是純PET（0.15 W/(m·K)）的35.8倍，也遠優于相同質量分數下直接混合的(BN7.5/Co-C@C)/PET復合材料（4.03 W/(m·K)）。采用同軸法測試并計算得出在頻率為4.72 GHz時，45 wt% BN7.5@Co-C@C/PET復合材料的最小反射損耗（RLmin）達-63.1 dB、對應有效吸收帶寬（EAB）為1.28 GHz（4.08~5.36 GHz），實現了C波段優異的電磁波吸收性能。
論文亮點
1. 利用PDA的超強黏附性并結合“正向沉積-逆向生長”機制，通過一鍋法將ZIF-67分散錨定在BN表面，將其熱解產物BN@Co-C@C作為異質結構導熱/吸波填料與PET共混制備了BN@Co-C@C/PET復合材料。
2. 當BN與ZIF-67@PDA的質量比為7.5:1且BN7.5@Co-C@C的質量分數為45 wt%時，BN7.5@Co-C@C/PET復合材料λ達到5.37 W/(m·K)，是純PET（0.15 W/(m·K)）的35.8倍，也遠優于相同質量分數下直接混合的(BN7.5/Co-C@C)/PET復合材料（4.03 W/(m·K)）。
3. 測試頻率為4.72 GHz時，45 wt% BN7.5@Co-C@C/PET復合材料的RLmin達-63.1 dB、對應EAB為1.28 GHz（4.08~5.36 GHz），實現了C波段優異的電磁波吸收性能。
第一作者：鐘洨
郵件地址：[email protected]
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