改性SiO_2气凝胶微球凝胶注模法制备块体材料  

Preparation of Bulk Material by Gel-casting Method with Modified Silica Aerogel Microspheres

作　　者：陶艳平 何方[1] 张德印 程娟[1] 吴菊英[2] 黄瑜鸿 邢涛[2] 

机构地区：[1]河南工业大学,材料科学与工程学院,河南郑州450001 [2]中国工程物理研究院总体工程研究所,四川绵阳621900

出　　处：《粉末冶金技术》2015年第4期264-269,共6页Powder Metallurgy Technology

基　　金：国家自然科学基金委员会和中国工程物理研究院联合基金资助项目(NSAF)(11076010);河南工业大学自然科学基础研究重点培育计划(2012JCYJ10)

摘　　要：以改性SiO_2气凝胶微球为原料,玻璃粉为烧结剂,采用凝胶注模法制备形状可控的块体材料,考察了改性SiO_2气凝胶微球、玻璃粉含量和烧结制度对块体材料的性能、微观形貌及孔结构的影响。结果表明:固相量一定时,低熔点玻璃粉含量越高,块体越致密,强度越高,孔隙率越低;当块体中聚合物含量增多时,加热后块体孔隙相对增加,同时聚合物碳化分解的产物很难排除;降低升温速率,延长保温时间可防止块体开裂,有利于有机物排除。经检测,固相量为70%(质量分数),气凝胶微球与低熔点玻璃粉质量比为1:1.5时,凝胶注模法制备的块体材料性能最佳:气孔率约为60%,比表面积为169.36 m^2/g左右,孔径分布主要在40nm以下,具有明显介孔特征。Using modified silica aerogel microsphere as raw material, glass powder as agglomerant, shape controllable bulk material was fabricated by gel-casting process. The effect of modified silica aerogel microsphere and glass powder contents and sintering regime on the sintering properties, microstrneture and pore structure were investigated. The result shows that if solid loading ratio is fixed, with increasing glass powder content, monolithic porous material with high strength and low porosity can be achieved. What＇s more, with increasing polymer loading ratio, the porosity increases, and the product of carbonation decomposition of polymer is difficult to remove. In addition, reducing the heating rate and prolonging the holding time contribute to prevent the bulk material from cracking and promote the organic matter eliminating. When solid loading ratio is 70% and silica aerogel microsphere： glass powder ration is 1 ：1.5, optimal material with comprehensive performances, including porosity of 60%, the specific surface area of 169. 36 m2/g, the main pore size distribution of below 40 nm, can he obtained.

关 键 词：SiO_2气凝胶微球 改性 凝胶注模成型 块体材料 

分 类 号：TQ127.2[化学工程—无机化工]