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用共沉淀法制备甘氨酸(简称Gly)插层Mg3Al水滑石(简称Gly-Mg3Al LDHs),利用甘氨酸等电点的性质实现了Mg3Al水滑石在pH=3~4水溶液中的剥离,并将剥离出的LDHs纳米片层与蒙脱土进行插层组装,制备出Mg3Al水滑石/蒙脱土层状复合材料。用X射线粉末衍射、红外光谱、N2吸附-脱附以及电泳仪等手段对样品进行了表征。结果表明,制备出的GlyMg3Al LDHs结构规整,晶相单一,甘氨酸以42°的倾角排列于水滑石层间。在nGly∶nNO3-=1∶2的条件下制备的Gly-Mg3Al LDHs剥离效果最好,剥离后形成的无机聚合粒子的zeta电位介于35 mV~40 mV之间,剥离液可以稳定存在72 h。所得层状复合材料的层间距为1.44nm,此值为单元LDHs片层与单元蒙脱土片层的厚度之和,证明LDHs纳米片层与蒙脱土进行了有序交叉叠层。
Preparation of glycine (Gly) intercalation Mg3Al hydrotalcite (Gly-Mg3Al LDHs) by coprecipitation method, using the nature of glycine isoelectric point to achieve the stripping of Mg3Al hydrotalcite in pH = 3-4 aqueous solution and stripping out LDHs nanosheets and montmorillonite were intercalated and assembled to prepare Mg3Al hydrotalcite / montmorillonite layered composites. The samples were characterized by X-ray powder diffraction, infrared spectroscopy, N2 adsorption-desorption and electrophoresis. The results show that the prepared GlyMg3Al LDHs have a regular structure and a single crystal phase, and glycine is arranged at an inclination of 42 ° between the hydrotalcite layers. The stripping effect of Gly-Mg3Al LDHs prepared under the condition of nGly: nNO3- = 1: 2 is the best, the zeta potential of the inorganic particles formed after stripping is between 35 mV and 40 mV, and the stripping solution can stably exist for 72 h . The interlayer spacing of the resulting layered composites was 1.44 nm, which is the sum of the thicknesses of the unit LDHs sheets and the montmorillonite sheets, indicating that the LDHs nanosheet sheets and the montmorillonites were cross-laminated in an orderly manner.