二氧化硅复合气凝胶红外隐身材料的制备及表征  

Preparation and Characterization of Silica Composite Aerogels for Infrared Stealth

作　　者：韩朝江[1] 马拥军[1,2] 裴重华[1] 雒敏婷[1] 邢玉静[1] 

机构地区：[1]四川省非金属复合与功能材料重点实验室-省部共建国家重点实验室培育基地,西南科技大学,四川绵阳621010 [2]分析测试中心,西南科技大学,四川绵阳621010

出　　处：《红外技术》2012年第9期551-556,共6页Infrared Technology

基　　金：四川省非金属复合与功能材料重点实验室-省部共建国家重点实验室培育基地开放基金,编号:10zxfk25

摘　　要：以正硅酸乙酯(TEOS)为硅源,采用酸碱两步催化法经过溶胶-凝胶和冷冻干燥制备出SiO2气凝胶基材,并在凝胶老化过程中通过加入不同含量β-氯乙基二甲胺盐酸盐(β-DCH)制备出兼具中远红外吸收特性的硅基复合气凝胶。利用X射线衍射、扫描电子显微镜、氮吸附-脱附和傅里叶红外吸收光谱对气凝胶的结构和性能进行表征。结果表明:基材和复合气凝胶的表观密度分别为0.25g/cm3和0.36～0.54 g/cm3;基材和大部分复合气凝胶均为非晶型,只有当复合气凝胶中N:Si摩尔比为1时才有微弱的β-DCH结晶峰出现;所添加的胺盐以球形颗粒或无规则块状附着于硅气凝胶网络结构中;基材属于介孔材料,比表面积、最大孔容和平均孔径分别为:524.5m2/g、1.209 cm3/g和9.216 nm,添加胺盐后复合气凝胶不断向非多孔、大孔材料过渡,比表面积、最大孔容和平均孔径分别为:1.688～103.5 m2/g、0.0079～0.2695 cm3/g和10.42～18.68 nm。复合气凝胶在中远红外窗口具有宽频吸收的特性,且随着β-DCH量的增加,中红外相对吸收强度成比例增强。The silicon aerogel substrate was prepared by a two-step base/acid catalyzed sol-gel process using tetraethoxysilane （TEOS） as silicon source and by freeze drying. By adding different content of β-Dimethylaminoethyl chloride hydrochloride （β-DCH） to the substrate during the aging process, Composite aerogels with broadband absorption in mid- and far-infrared windows was prepared. The structure and property of composite aerogels were characterized by X-ray diffraction（XRD）, scanning electron microscopy（SEM）, N2 physisorption at 77 K and fourier-transform infrared spectroscopy （FT-IR）. Results showed that： The apparent density of silicon aerogel substrate and composite aerogels are 0.25 g/cm^3 and 0.36-0.54 g/cm^3 respectively. Both the silicon substrate and most composite aerogels are amorphous. Only when the N：Si mol ratio reaches as high as 1, does the comosity aerogel have the weak crystallization peak of β-DCH. The β-DCH agglomerated into spherical particles or irregular blocks adhering to the whole three-dimensional network of silicon aerogel. The silicon aerogel is mesoporous material, which has the specific surface area about 524.5 m^2/g, total pore volume about 1.209 cm^3/g and average pore diameter about 9.216 nm. The composite aerogels transform to non-porous and macropore materials gradually with the increase of β-DCH, which has the specific surface area about 1.688-103.5 m^2/g, total pore volume about 0.0079-0.2695 cm^3/g and average pore diameter about 10.42418.68 nm. Composite aerogels have broadband absorption characteristic in mid- and far-infrared. The relative absorption intensity in mid-infrared increased in proportion with the increased content of β-DCH.

关 键 词：红外隐身 二氧化硅 β-氯乙基二甲胺盐酸盐 气凝胶 

分 类 号：TJ765.5[兵器科学与技术—武器系统与运用工程]