有序介孔C-Al2O3纳米复合材料的合成及其红外发射率

以嵌段共聚物F127(PEO106PPO70PEO106, MW=12600)为模板剂, 异丙醇铝为铝源, 低分子量的酚醛树脂为碳源, 通过溶胶-凝胶三元共组装法合成了C-Al2O3纳米复合材料. 用X射线衍射(XRD)、透射电子显微镜(TEM)及N2吸脱附法对该复合材料进行结构与性能表征, 结果显示复合材料MC5A5具有较好的有序介孔结构, 其比表面积可达175 m2·g-1, 孔容0.22 cm3·g-1. 又以三元乙丙橡胶(EPDM)为粘结剂, 与介孔纳米复合材料混合制备涂层. 随着复合材料中Al2O3质量分数从30%增加到70%, 该涂层的红外发射率从0.575降至0.456, 表明Al2O3能有效降低复合材料的红外发射率, 预示该复合材料在军事装备隐身需求领域将具有较好的应用前景.

Syntheses and Infrared Emissivities of Ordered Mesoporous C-Al2O3 Nanocomposites

C-Al2O3 nanocomposites were synthesized via the sol-gel tri-constituent co-assembly process using an amphiphilic triblock copolymer F127 (PEO106PPO70PEO106, MW=12600) as a template, aluminum iso-propoxide as an inorganic source, and resol as an organic precursor. X-ray diffraction (XRD), transmission electron microscopy (TEM), and nitrogen adsorption/desorption were used to characterize the structures and properties. The results showed that the nanocomposite MC5A5 has ordered mesoporous structures with a high specific surface area of 175 m2·g-1 and a pore volume of 0.22 cm3·g-1. Low infrared emissivity coatings were obtained using the ethylene-propylene-diene monomer (EPDM) as an adhesive and the ordered mesoporous C-Al2O3 nanocomposites as a filling. As the mass percentage of Al2O3 was increased from 30% to 70%, the infrared emissivity decreased from 0.575 to 0.456. Al2O3 can effectively reduce the infrared emissivities of nanocomposites. Ordered mesoporous C-Al2O3 nanocomposites are thus promising for application in martial equipment.