SnO_2系溶胶-凝胶转变的流变学研究

Rheology Study on Sol-Gel Transition of SnO_2 Systems

通过ＳｎＯ２溶胶体系流变学实验研究，给出切粘度η、特性粘度［η］及 ｐＨ值随时间变化曲线，在此基础上深入分析讨论了ＳｎＯ２胶粒生长动力学过程特征，结构演变规律及生长过程中伴随的质子Ｈ＋释放现象．实验和理论揭示出ＳｎＯ２胶粒生长遵循三阶段模型和胶粒结构不变性规律，同时溶胶液酸性对生长动力学速率有较大影响．

By rheological experimental measurements of SnO2 sol systems derived by the precursor Tetrabutylorthostannate Sn(OBun)4, it was reported that tear viscosity η, intrinsic viscosity [η] and pH values of the sol solution systems varied dynamically with time. Based on the rheologically dynamic observations, the growth character of SnO2 sol grains and its structural evolution rule were discussed, and proton H+ production phenomena associated with sol grain growth process were also explained. From experimental investigations and theoretical discussion, the growth process of SnO2 sol grains is controlled by a three-stage growth model, and grain structure keeps invariant during the growth period before sol→gel transformation and sol solution acidity (pH) influences profoundly the sol grain growth rates.