单、双十二烷基季铵盐改性钠基蒙脱石的实验与理论研究  

Experimental and theoretical study on mono- and di-dodecyl quaternary ammonium salt modified sodium montmorillonite

作　　者：蒋昊 尹静梅[1] 李慎敏[1] JIANG Hao;YIN Jing-mei;LI Shen-min(Liaoning Key Laboratory of Bio-organic Chemistry,Dalian University,Dalian 116622,China)

机构地区：[1]大连大学辽宁省生物有机化学重点实验室,辽宁大连116622

出　　处：《分子科学学报》2020年第5期361-367,I0001,共8页Journal of Molecular Science

基　　金：国家自然科学基金重点资助项目(21133005);大连市高层次人才资助项目(2016RJ11)。

摘　　要：采用2种烷基季铵盐插层剂十二烷基三甲基氯化铵(DTAC)和双十二烷基二甲基氯化铵(DDAC)对钠基蒙脱石(Na-MMT)进行改性实验,通过X射线衍射(XRD)和热重分析(TGA)对改性蒙脱石进行表征,并结合蒙特卡洛方法对改性蒙脱石模型体系进行分子模拟,在分子层次上探索季铵盐添加量及其单、双长链烷基的变化对改性蒙脱石结构与性质的影响.实验表征表明,随着季铵盐添加量的增大,单长链季铵盐改性蒙脱石体系层间距呈现台阶式增大趋势,而双长链季铵盐改性体系层间距呈现渐进增大趋势.蒙特卡洛模拟结果支持了表征,上述差异来自于插层季铵盐在蒙脱石层间分布结构的不同.Two alkyl quaternary ammonium salt intercalating agents, dodecyl trimethyl ammonium chloride(DTAC) and dodecyl dimethyl ammonium chloride(DDAC) were used to modify sodium-based montmorillonite(Na-MMT). In the experiments, X-ray diffraction(XRD) and thermogravimetric analysis(TGA) were used to characterize the modified montmorillonite, and the Monte Carlo method was used to perform molecular simulation of the modified montmorillonite model system and explore the reasons at the molecular level. The effect of ammonium salt addition and the change of single and double long chain alkyl groups on the structure and properties of modified montmorillonite. Experimental characterization shows that with the increase of the amount of quaternary ammonium salt, the interlayer distance of the single-long-chain quaternary ammonium salt modified montmorillonite system increases stepwise, while the interlayer distance of the double-long-chain quaternary ammonium salt modified system shows a gradual increase trend. The Monte Carlo simulation results support the characterization, pointing out that the above differences come from the different distribution structure of the intercalated quaternary ammonium salt between the montmorillonite layers.

关 键 词：钠基蒙脱石 单、双十二烷基季铵盐 插层 蒙特卡洛模拟 

分 类 号：O641[理学—物理化学]