Preparation And Modification Of Layered Double Hydroxides

(LDH)Layers double hydroxides having special layered structure, adjustedinterlayer spacing and the diversity of anion of laminates, can be widely applied tosome fields such as catalysis,medicine, absorption, etc, especially in the fire retardantfield, received the great concern. Because of Nano Mg/Al LDH structure and sizeeffect, its fire retardant restraining smoke is further more obvious compared withregular LDH, so to be prepared Nano Mg/Al LDH already become domestic andinternational research focus of the field. However, it is still researched at laboratory atpresent. Obviously having optimized the technical, lowed costs, prevented reunion,have already become the key of Nano Mg/Al LDH that could be applied inindustrialization. This text studied the preparation technology of nano LDH and itssurface organizing modification. This dissertation included following contents:（1）The Mg/Fe-CO₃-LDH powders were prepared by the solid phase reaction atroom temperature. Mg/Fe molar ration was investigated to analyze the product. Theresults show that when the Mg/Fe molar ratio of3:1, the regular structure and thermalstability of the samples increased.（2）One pot in situ synthesis of hydrophobic magnesium aluminum hydroxide composite particles using the grind of method to treat the LDH preliminarily, and thenfree radicals in situ polymerzation was used to modify the LDH. The results show thathydrohobic nano Mg/Al-LDH samples were obtained, and the MMA monomer wassuccessfully grafted onto the surface of the LDH. In addition, after the modification,the stability of the LDH has been increased.（3）Nano sized hydrophobic Mg/Al-LDH was synthesized using smartwater assisted manual grinding method. Under the presence of a small amount ofwater, the intercalated LDH was obtained by grinding reaction. The analysis showedthat the crystalline properties of the product increase with the amount of intercalatingagent.（4）The crystallinity, phase, morphology and particle size of the products werecharacterized by X ray diffraction （XRD）, scanning electron microscope （SEM）,Fourier transform infrared spectroscopy （FTIR） and thermal gravimetric （TG）analysis.