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研究了乙酰丙酮(acetylacetone)改性正丁醇锡(tinalkoxide)在氢氟酸、盐酸、氢溴酸、硝酸、乙酸和氨催化剂作用下的溶胶凝胶体系的动力学过程。利用近似线性聚合生长模型求出了不同催化剂作用下改性醇盐的平均缩合反应速率以及溶胶团簇的平均官能度,催化剂对平均缩合反应速率的影响按大小依次为硝酸、盐酸、乙酸、氨水和氢溴酸,各溶胶体系的平均官能度均为略大于2.0。氢氟酸作催化剂的体系产生白色沉淀。催化剂对体系凝胶时间影响大小依次为氨水、乙酸、盐酸、硝酸和氢溴酸。利用部分电荷模型计算了不同催化剂作用下改性锡醇盐分子体系的电荷分布,讨论了不同催化剂对改性锡醇盐水解和缩合反应的催化机理。
The kinetics of acetylacetone-modified sol-gel system of tinalkoxide with hydrofluoric acid, hydrochloric acid, hydrobromic acid, nitric acid, acetic acid and ammonia catalyst was studied. The average condensation reaction rate and the average functionality of the solvates under different catalysts were calculated by using the approximate linear polymerization growth model. The influence of the catalyst on the average condensation reaction rate was determined by the order of nitric acid, hydrochloric acid, acetic acid, ammonia water And hydrobromic acid, the average functionality of each sol system is slightly greater than 2.0. Hydrofluoric acid as a catalyst system produces a white precipitate. The influence of catalyst on the gelation time was ammonia, acetic acid, hydrochloric acid, nitric acid and hydrobromic acid. The partial charge model was used to calculate the charge distribution of the modified alkoxide system under different catalysts. The catalytic mechanism of different catalysts on the hydrolysis and condensation of the modified tin alkoxide was discussed.