铝改性硅溶胶胶粒组成与结构关系研究

INVESTIGATION ON THE RELATIONSHIP BETWEEN COMPOSITON AND STRUCTURE OF AL- MODIFED SILICA SOL PARTICLES

用ＦＴ－ＩＲ，２７Ａｌ－ＮＭＲ和２９＿Ｓｉ－ＮＭＲ研究了不同Ａｌ／Ｓｉ摩尔比的铝改性硅溶胶胶粒结构。结果表明：在Ａｌ／Ｓｉ比为０．２～０．５的范围内，铝改性硅溶胶胶粒中Ａｌ主要是以在第二配位圈上与［ＳｉＯ＿４］四面体相连接的［ＰＡｌＯ＿４］四面体的形式存在；Ａｌ／Ｓｉ比的不同，其中铝硅酸阳离子结构也各异，根据２９＿Ｓｉ－ＮＭＲ测定结果能较好地定量计算出各种结构的铝硅酸阴离子的分布；ＩＲ谱的８４０～１３００ｃｍ＿（－１）范围内的各吸收带的频率随胶粒的Ａｌ／Ｓｉ摩尔比的增加而减小并存在较好的线性关系。

The structure of the Al-modified silica sol particles with different AL/Si mole ratio was investi-gated by means of FT-IR,27_Al-NMR and29_Si-NMR measurements.The results show that most of the Alatoms in the Al-modified silica sol particles exist in the form of AlO_4 tetrahedra linked with Si atoms in thesecond coordination sphere in the range of Al/ Si from 0.2 to 0.5.The structure of the aluminosillcate anion(continued On p.183)Received:April 11,1994.Correspondent:Fang Yonghao,Department of Materials Science and Engineering,Nanjing Institute of Chemical Technology,Nanjing 210009.cbanges with Al/Si ratio and the distribution of the aluminosilicate anion with dinerent Al/Si in the samplescan be calculated with satisfactory accuracy from the result of￣(29)Si-NMR measurement. The IR absorption fre-quencies in the range of 840～1300cm,￣(-1) decrease linearly with the increase of Al/Si.