Wood‐Derived, Vertically Aligned, and Densely Interconnected 3D SiC Frameworks for Anisotropically Highly Thermoconductive Polymer Composites

Abstract

Construction of a vertically aligned and densely interconnected ordered 3Dfiller framework in a polymer matrix is a challenge to attain significant thermal conductivity (TC) enhancement efficiency. Fortunately, many biomaterials with unique microstructures can be found in nature. With inspiration from wood, artificial composites can be rationally designed to achieve desired properties. Herein, the authors report a facile and effective approach to fabricate anisotropic polymer composites by biotemplate ceramization technology and subsequent vacuum impregnation of epoxy resin. The hierarchical microstructure of wood is perfectly replicated in the cellular biomass derived SiC (bioSiC) framework by carbothermal reduction. Owing to the anisotropic architecture of bioSiC, the epoxy composite with vertically aligned dense SiC microchannels shows interesting properties, including a high TC (10.27 W m −1 K −1 ), a significant enhancement efficiency (259 per 1 vol% loading), an outstanding anisotropic TC ratio (5.77), an extremely low coefficient of linear thermal expansion (12.23 ppm K −1 ), a high flexural strength (222 MPa), and an excellent flame resistance. These results demonstrate that this approach is expected to open a new avenue for design and preparation of high performance thermal management materials to address the heat dissipation of modern electronics.

Implementation of Epoxy Resin Composites Filled with Copper Nanowire-Modified Boron Nitride Nanosheets for Electronic Device Packaging

“…This was mainly owing to the bridging effect of the Cu NWs grown on BNNSs; their synergy resulted in a "highway" for phonons that facilitated heat conduction within the composite. 25,39 The DSC and TGA results for all the samples presented in Figure S4 show that the introduction of the filler caused a slight decrease in the T g of the Cu NWs/BNNSs@PDA/ER composite, which remained at >100 °C. Moreover, the T g of the composite was higher than that of the BNNSs/ER composite with the same filler loading rate.…”

Research progress of high thermal conductivity polyimide dielectric films

“…3)导热通路的设计及有效构筑. 针对以上挑战, 研 究者们提出了许多解决方案, 通过对填料和基体的 表面改性以及利用尺寸效应改善填料在基体中的 分散问题 [47−50] ; 通过填料、基体界面行为及界面 调控, 组分相互作用的调控与设计来降低界面热 阻 [51,52] ; 定向构筑三维导热网络 [53] 、构建互穿或两 相/多连续相导热通路 [54,55] 、向自然学习 [56] 、基于 仿生的结构 [57] 等来构筑导热通路. 接下来, 分别介 绍本征型和填充型导热PI的最新研究进展, 总结 正在遇到的科学技术问题并展望未来发展面临的 机遇和挑战.…”

“…许 多学者利用静电纺丝技术开展了大量导热PI的研 究工作 [112] . 在导热填料部分提到的形成双网络结 构的PI膜 [55] , PAA/BNNS纤维和PVA/CNT纤 维通过共静电纺丝的技术制备, 这两种前驱体纤维 在膜中均匀交织, 前驱体膜经过高温处理后进行 PVA的炭化和PAA的热亚胺化, 从而制备PI复 合薄膜. Guo等 [113] 此外, 利用冰模板法 [108] 、冷冻干燥技术 [114] 图 16 PI复合材料的平面热导率(a)和跨平面热导率(b) [107] Fig.…”

Hierarchically multifunctional thermally conductive Boron Nitride/Polyurethane fibrous membranes via constructing alternating multi-layer orientation structure

“…However, some crucial drawbacks were identi ed that impede the practical application of the modern device. High ller content while limited thermal conductivity is one of the main problems currently faced [19]. Additionally, the ensuing problem is that due to the introduction of llers the polymer chain is con ned by the ller sheets, and it is di cult to release the hidden length [20][21][22][23][24].…”