Capková P, Pospísil M, Valásková M, Merínská D, Trchová M, Sedláková Z, Weiss Z, Simoník J
Institute of Materials Chemistry, Technical University Ostrava, 17 Listopadu, 70833 Ostrava, Czech Republic.
J Colloid Interface Sci. 2006 Aug 1;300(1):264-9. doi: 10.1016/j.jcis.2006.03.033. Epub 2006 May 2.
Structural analysis of Na-montmorillonite co-intercalated with octadecylamine and stearic acid was carried out using combination of experiment: X-ray powder diffraction and IR spectroscopy with molecular modeling (force field calculations) in Cerius(2) modeling environment. Results of structure analysis revealed the chemical reaction of guest compounds leading to the formation of octadecylammonium stearate. This reaction may occur even before the intercalation out of the interlayer space of montmorillonite. The presence of octadecylammonium stearate in the samples was clearly confirmed by IR spectroscopy and X-ray diffraction. Present results also showed that: (1) Stearic acid itself does not intercalate into Na-montmorillonite; (2) cointercalation with octadecylamine led to the formation of octadecylammonium stearate, which was successfully intercalated into the interlayer space of montmorillonite, and (3) Na-montmorillonite intercalated with octadecylammonium stearate does not create a stable structure. Intercalated samples in ambient conditions undergo gradual decomposition, accompanied by the release of octadecylammonium stearate from the interlayer space and rearrangement of the interlayer structure. Co-intercalation of STA and ODA to lower the octadecylamine content and consequently to suppress the unfavorable effect of amine groups on the polymer matrix in nanocomposite, was investigated.
在Cerius(2)建模环境中，结合X射线粉末衍射和红外光谱以及分子建模（力场计算）。结构分析结果揭示了客体化合物的化学反应，导致硬脂酸十八烷基铵的形成。这种反应甚至可能在从蒙脱石的层间空间插层之前就发生。通过红外光谱和X射线衍射清楚地证实了样品中存在硬脂酸十八烷基铵。目前的结果还表明：(1) 硬脂酸本身不会插入钠蒙脱石中；(2) 与十八烷基胺共插层导致形成硬脂酸十八烷基铵，其成功地插入蒙脱石的层间空间，并且(3) 插层有硬脂酸十八烷基铵的钠蒙脱石不会形成稳定结构。在环境条件下的插层样品会逐渐分解，伴随着硬脂酸十八烷基铵从层间空间释放以及层间结构的重排。研究了共插层STA和ODA以降低十八烷基胺含量，从而抑制胺基对纳米复合材料中聚合物基体的不利影响。
