本论文以Al(OH)3胶体为研究对象, 使用同步辐射SAXS技术并结合FTIR、SEM、DLS、Zeta potential表征手段, 考察了Al(OH)3胶体粒子在老化时间0 - 135 min下的分形结构演化规律, 并提出了一种可能的生长机制。不同老化时间下的双对数坐标图呈现明显的线性, 说明胶体样品存在分形结构。结果表明, 随着老化时间的延长, 质量分形维数Dm由25 min时的2.29增加至85 min的2.78;95 min - 135 min时, Dm值在2.76 - 2.79范围内, 基本不发生变化。这说明, 老化时间在25 min - 85 min时, 体系初级颗粒由最初的相对分散状态快速团聚为大尺寸的团簇, 最后形成致密的凝胶。95 min - 135 min, 凝胶过程已经完成, 胶粒尺寸不发生变化, 135 min时胶块可能发生破裂。

In this paper, the fractal structure evolution of aluminum hydroxide colloid particles under aging time 0-135 minute was investigated by using synchrotron radiation SAXS technology and other potential characterization methods, including FTIR, SEM, DLS, and Zeta potential.The possible growth mechanism was proposed. The scattering double logarithmic coordinate plots under different aging times showed obvious linearity, indicating that significant differences in the fractal structure of the samples. With the extension of aging time increased from 25 minute to 85 minute, the mass fractal dimension Dm increased from 2.29 to 2.78. The Dm values were in the range of 2.76 - 2.79, with little change between 95 and 135 minutes. This indicated that the primary particles of the system will rapidly reunite from the initial relative dispersion state to larger size clusters and finally form dense gels at the aging time 25 minute - 85 minute. The gel process had been completed, the size of the colloid particles did not change during 95 -135 minute, and the adhesive block may break at 135 minute.<通讯作者>邴柳洁(1996-), 女, 硕士研究生学历, 就职于北京石油化工工程有限公司, 主要从事传热计算等工艺设计工作, 辅修同步辐射SAXS技术在胶体、分子筛等材料中的应用