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利用２９Ｓｉ和１ＨＮＭＲ方法研究了ＴＳ１分子筛合成过程中正硅酸乙酯（ＴＥＯＳ）的水解行为．１ＨＮＭＲ结果表明，ＴＥＯＳ在四丙基氢氧化铵（ＴＰＡＯＨ）溶液中的水解速度快于在四乙基氢氧化铵（ＴＥＡＯＨ）中的水解速度．ＴＥＯＳ水解后的２９ＳｉＮＭＲ谱显示，ＴＥＯＳ在ＴＰＡＯＨ中水解产生的聚合硅酸根物种的分布与在ＴＥＡＯＨ中的类似，都存在着单体、二聚、三聚及环聚等硅酸根物种的平衡，但ＴＥＯＳＴＥＡＯＨ体系中低聚硅酸根物种的浓度明显大于ＴＥＯＳＴＰＡＯＨ中的浓度．向水解后的样品中添加水，可促使多聚硅酸根物种转化为低聚物种．大量异丙醇的加入将导致单聚和二聚硅酸根物种的高聚．钛酸四丁酯加入到ＴＥＯＳＴＰＡＯＨ水解体系中得到的２９ＳｉＮＭＲ结果明显不同于ＴＥＯＳＴＥＡＯＨ水解体系．
The 29Si and 1HNMR methods were used to study the hydrolysis of tetraethoxysilane (TEOS) during the synthesis of TS1 molecular sieve. The 1H NMR results showed that the hydrolysis of TEOS in tetrapropylammonium hydroxide (TPAOH) solution was faster than that in tetraethylammonium hydroxide (TEAOH). The 29Si NMR spectra after TEOS hydrolysis show that the distribution of polymeric silicate species produced by hydrolysis of TEOS in TPAOH is similar to that in TEAOH with the balance of silicate species such as monomeric, dimeric, trimeric, and cyclic poly The concentration of oligomeric silicate species in TEOS-TEAOH system was significantly higher than that in TEOS-TPAOH. Adding water to the hydrolyzed sample can promote the conversion of polysilicate species to oligomeric species. The addition of a large amount of isopropanol will result in the polyaddition of monomeric and dimeric silicate species. Tetramethyl titanate added to the TEOS TPAOH hydrolyzed system obtained 29Si NMR results significantly different from the TEOS TEAOH hydrolysis system.