Size-controlled graphite nanoplatelets: thermal conductivity enhancers for epoxy resin
Size-controlled graphite nanoplatelets: thermal conductivity enhancers for epoxy resin
复制标题
尺寸控制的石墨纳米片：环氧树脂的导热增强剂
DOI：
10.1007/s10853-019-03525-5
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发表时间：
2019
影响因子：
4.5
通讯作者：
Liu Guichang
中科院分区：
文献类型：
--
作者：
Xing Zhonghao;Sun Wen;Wang Lida;Yang Zhengqing;Wang Suilin;Liu Guichang
石墨纳米片（GNPs）由于其独特的晶体结构是由sp2杂化碳原子形成的层状石墨烯构成的，是一种优秀的导热填料，但其制备过程耗时长。本文开发了一种高效、低成本的方法，可以在不破坏晶体结构的情况下制备尺寸可控的GNPs。在廉价的商用洗涤剂中，用硝酸在0.5 h内处理可获得平均尺寸约为20 μm的GNPs，在6 h内控制超声时间可获得1-5 μm的GNPs。此外，将~ 20 μm GNPs与1 ~ 5 μm GNPs在环氧树脂中结合制备了热网。现有研究定性地证明了具有明显粒径差异的杂化碳填料可以通过粒径协同效应增强环氧树脂的导热性，但很少有定量研究关注对粒径协同效应的优化。本研究表明，通过调整小尺寸GNPs的尺寸、不同尺寸GNPs的比例和杂化填料的含量，可以实现不同程度的尺寸协同效应。结果表明：当杂化填料的掺量为20 wt%， ~ 20 μm GNPs与1.82 μm GNPs的比例为17:3时，复合材料的尺寸增效效果最佳，导热系数达到1.33 W/m K，比纯环氧树脂提高739%；该复合材料具有高导热性和经济竞争力，在热管理领域具有广阔的应用前景。
Graphite nanoplatelets (GNPs) are outstanding thermal conductive fillers due to their unique crystal structure which consists of layered graphene formed bysp2-hybridized carbon atoms, but their preparation process is time-consuming. Herein, a high-efficiency and low-cost method is developed to prepare GNPs with controlled size without destroying their crystal structure. GNPs with an average size around 20 μm are obtained by a facile nitric acid treatment within 0.5 h, and 1–5 μm GNPs are produced by controlling ultrasonic time within 6 h in cheap commercial detergent. In addition, thermal network is fabricated by combining ~ 20 μm GNPs with 1–5 μm GNPs in epoxy. The existing researches have qualitatively demonstrated that hybrid carbon fillers with obvious size differences can enhance the thermal conductivity of epoxy through size synergistic effects, but rare quantitative studies pay attention to optimize size synergistic effects. This work demonstrates that different degrees of size synergistic effects can be achieved by tuning the size of small-sized GNPs, the proportion of different sized GNPs and the content of hybrid fillers. The results show that when the hybrid filler loading is 20 wt% and the ratio of ~ 20 μm GNPs to 1.82 μm GNPs is 17:3, the composite produces the optimal size synergistic effect and thermal conductivity reaches 1.33 W/m K, increased by 739% over neat epoxy. This composite has promising application in the thermal management areas due to its high thermal conductivity and economic competitiveness.