Thermal conductivity of epoxy composites filled by thermally reduced graphite oxide with different reduction degree
Thermal conductivity of epoxy composites filled by thermally reduced graphite oxide with different reduction degree
复制标题
不同还原度热还原氧化石墨填充环氧复合材料的导热性能
DOI：
10.1177/0021998317696137
复制
发表时间：
2017-05-01
影响因子：
2.9
通讯作者：
Du, Xiaoze
中科院分区：
文献类型：
--
作者：
Sun, Yingying;Chen, Lin;Du, Xiaoze
通过对氧化石墨在不同热处理温度下的热还原，制备了一系列选择性还原氧化石墨，并将其作为增强环氧复合材料导热性能的填料。在600℃~1000℃范围内，选择性还原氧化石墨的还原程度随退火温度的升高而增大。选择性还原氧化石墨/环氧复合材料的面外导热系数(Κo)显著高于氧化石墨/环氧复合材料。当填充量为5.4wt%时，在1000℃，Κ下得到的选择性还原氧化石墨氧达到0.674 W/m·K，是纯环氧树脂的450%。增强的Κo可归因于选择性还原氧化石墨在环氧树脂中的良好分散性以及它们的边缘重叠在环氧树脂中形成有效的导热路径。然而，由于选择还原氧化石墨片的还原程度越高，其与环氧树脂的界面结合强度就越低，因此其导热系数的提高仍然低于还原程度较高的选择还原氧化石墨。
A series of selectively reduced graphite oxide was prepared by thermal reduction of graphite oxide at different annealing temperatures and used as fillers to enhance thermal conductivity of epoxy composites. The reduction degree of selectively reduced graphite oxide increases with annealing temperature changing from 600℃ to 1000℃. The out-of-plane thermal conductivity (Κo) of selectively reduced graphite oxide/epoxy composites is remarkably higher than that of graphite oxide/epoxy. For the selectively reduced graphite oxide obtained at 1000℃, Κo reaches 0.674 W/m·K when filler content is 5.4 wt%, which is 450% of pure epoxy. The enhanced Κo can be attributed to the better dispersion of selectively reduced graphite oxide in epoxy and their edges overlap to form effective thermal conductive paths in epoxy matrix. However, the achieved thermal conductivity enhancement is still comparatively lower than that of selectively reduced graphite oxide with higher reduction degree, since the interfacial bonding strength between selectively reduced graphite oxide and epoxy decreases when reduction degree of selectively reduced graphite oxide flakes becomes higher.