Carbon Aerogel Composites Prepared by Ambient Drying and Using Oxidized Polyacrylonitrile Fibers as Reinforcements
Carbon Aerogel Composites Prepared by Ambient Drying and Using Oxidized Polyacrylonitrile Fibers as Reinforcements
复制标题
氧化聚丙烯腈纤维作为增强体常温干燥制备碳气凝胶复合材料
DOI：
10.1021/am201287a
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发表时间：
2011-12-01
影响因子：
9.5
通讯作者：
Zhao, Nan
中科院分区：
文献类型：
--
作者：
Feng, Junzong;Zhang, Changrui;Zhao, Nan
采用共热解法制备了碳纤维增强炭气凝胶复合材料（C/CAs）。采用RF溶胶浸渍PAN纤维毡，经老化、乙醇交换、常压干燥得到RF气凝胶复合材料。在碳化时，PAN纤维与RF气凝胶一起收缩，从而减小了纤维增强体与气凝胶基体之间的收缩率差异，并且导致C/CA没有任何明显的裂纹。C/CA的三点弯曲强度为7.1 +/- 1.7 MPa，并且在300 ℃空气中的热导率为0.328 W m（-1）K-1。这些复合材料可用作高温绝热体（惰性气氛或真空）或热防护系统中相变材料的载体。
Carbon fiber-reinforced carbon aerogel composites (C/CAs) for thermal insulators were prepared by copyrolysis of resorcinol-formaldehyde (RF) aerogels reinforced by oxidized polyacrylonitrile (PAN) fiber felts. The RF aerogel composites were obtained by impregnating PAN fiber felts with RF sols, then aging, ethanol exchanging, and drying at ambient pressure. Upon carbonization, the PAN fibers shrink with the RF aerogels, thus reducing the difference of shrinkage rates between the fiber reinforcements and the aerogel matrices, and resulting in C/CAs without any obvious cracks. The three point bend strength of the C/CAs is 7.1 +/- 1.7 MPa, and the thermal conductivity is 0.328 W m(-1) K-1 at 300 degrees C in air. These composites can be used as high-temperature thermal insulators (in inert atmospheres or vacuum) or supports for phase change materials in thermal protectidn system.