NMR研究表面活性剂在MCM-41分子筛合成溶胶体系中的作用机制

The Role of Surfactant in the Synthetic Gel of MCM-41 Molecular Sieve by NMR

在中孔材料MCM—41分子筛的合成溶胶体系中，利用1H、14N、13CNMR研究考察表面活性剂CTMABr在合成溶胶体系晶化过程中的模板作用机制，发现表面活性剂的局部浓缩效应（LocalConcentratedEffect），并提出了表面活性剂在合成溶胶体系中可能的作用机制。

The role of surfactant CTMABr in the synthetic gel system at the process of synthesisof mesoporous material MCM-41 molecular sieve has been studied by 1H, 14N, 13C NMR techniques. A Local Concentrated Effect (LCE) of surfactant is discovered. And a possible formationmechanism of mosoporous molecular sieve MCM-41 with the role of surfactant in the syntheticgel is also proposed, which is via the condendation and self-assembly of silicon surfactantmicelles. Under the actual synthesis conditions to form a silicatropic mesophase followed by silicacrosslinking, then sllicate species condensed to generate local concentration phenomnon. Thiskind of LCE might cause the formation of a liquid-crystal mesostructure (hexagonal, lamellar,or cubic), the nature of which depends on the composition of the mixture, the pH, thetemperature, and the reaction time. Polycondensation of the silicate spedes lead to the formationof a rigid structure.