【摘要】 以ZrOCl2.8H2O为锆源,通过添加乙酸(HAC)、聚乙二醇600(PEG)和甲酰胺(FA)等化学添加剂调节溶胶-凝胶速率、胶体粒子的分散性和凝胶网络结构的均匀性,以环氧丙烷(PO)为凝胶促进剂制备ZrO2凝胶,再结合高温超临界干燥工艺制备出了有一定强度的、具有均匀网络结构的块体ZrO2气凝胶。采用SEM和BET等分析手段对制备的样品进行微观形貌和性能表征。结果表明:随着FA的增加,样品孔体积和平均孔径均减小,比表面积增大;随着PEG的增加,样品比表面积、孔体积、平均孔径均出现先增大后减小的规律。更多还原

【Abstract】 Monolithic ZrO2 aerogels with good strength performance and homogeneous network structure were prepared through sol-gel technology with ZrOCl2·8H2O as precursor.Acetic acid(HAC) was added to the system to control the process of sol-gel,polyethylene glycol 600(PEG) and formamide(FA) were supplied to make the gel network more homogeneous,propylene epoxide(PO) was added to promote hydrolysis and polycondensation progress,and then monolithic ZrO2 aerogels were obtained after being dried by high temperature supercritical fluid drying method(HTSCFD).Mechanism of ZrO2 aerogels preparation was discussed in this paper,and the effects of FA and PEG on the structure and morphology of the samples were also investigated.The microstructure and properties of the samples were characterized by SEM,BET and other analytic methods.The results showed that the pore volume and average pore size decreased,the specific surface area increased with the increasing of FA;pore volume,specific surface area and average pore size increased first,and then decreased after with the increasing of PEG.更多还原