Further lowering of temperature for sol-gel processing of ceramic powders

进一步降低陶瓷粉末溶胶-凝胶加工温度

• 批准号: 12450351
• 负责人: KAMIYA Kanichi
• 金额: $ 4.48万
• 依托单位: Mie University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2000
• 资助国家: 日本
• 起止时间: 2000 至 2001
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-12450351/
• 关键词: Sol-Gel method; α-alumina; alminum butoxide; acid-catalysis; TEOS; silica; X-ray diffraction; bio-silica; ゾルーゲル法; アルミニウムアルコキシド; 塩化アルミニウム; アルミナゲル; X線動径分布解析; ミリカゲル

Sol-gel preparation of α-alumina powders and silica glass at temperature as low as possible was aimed. Following results have been obtained.(1) Alumina gel powders prepared from the aluminum butoxide through the sol-gel reaction at 0 ℃, in the presence of HCI were partially (40 to 50 %) transformed to α-alumina around 500 ℃, when they were seeded with corundum particles to a level of 1 wt %.(2) The CL^- were forun to have an important role in the low temperature α-formation of alumina gels, and were considered to make chemical bridges between aluminoxane oligomers.(3) AlCl_3 and / or Al metal powders could replace aluminum alkoxide for low temperature formation of α-alumina.(4) The HNO_3-catalyzed alumina gel were completely transformed to α-alumina at 800 ℃.(5) The atomic scale structure of amorphous bio-silica, which was analyzed by X-ray diffraction technique, was very similar to fused silica (glass), suggesting the possibility of the room-temperature formation of silica glass even through sol-gel reaction of TEOS.(6) The silica prepared from TEOS by the sol-gel method in the presence of organic substances such as tartaric acid was revealed to have a structure similar to fused silica.

目的是在尽可能低的温度下用溶胶-凝胶法制备α-氧化铝微粉和二氧化硅玻璃。结果表明：(1)在盐酸存在下，由丁醇铝在0℃下通过溶胶-凝胶反应制备的氧化铝凝胶粉末，在加入1wt%的刚玉颗粒后，在500℃左右部分(40%~50%)转变为α-Al_2O_3。(2)CL~(2-)在氧化铝凝胶的低温形成过程中起着重要作用。(3)AlCl3和/或Al金属粉末可替代醇铝低温生成α-Al_2O_3.(4)HNO_3催化的氧化铝凝胶在800℃时完全转化为AlO-Al_2O_3.(5)X射线衍射分析表明，非晶态生物SiO_2的原子级结构与熔融SiO_2(玻璃)非常相似，在酒石酸等有机物存在下，用溶胶-凝胶法由正硅酸乙酯制备的二氧化硅具有与熔融二氧化硅相似的结构。