Preparation And Application Of Nano-Neodymium Oxide And Magnesium Hydroxide Whisker

Neodymium Oxide is an useful rare earth oxide.It is mainly used to Nd-Fe-B permanent magnet,television,glass painting,fluorescent material,laserable material and rubber industry additive.Because of the elegant hue and the good discoloration, neodymium oxide is used to ceramics,textile dye,superconductivity material and other journal of functional materials,it is increasing very aggressively.Furthermore the study of neodymium oxide in catalysis was more and more widely.The preparation method of nanomaterials is classifide as solid phase method, liquid phase method and gas phase method.The precipitation method of the liquid phase method is the most widely used.Low cost raw material,simple technology and easily extend are the advantage of chemical precipitation method.The frequently-used precipitator are ammonia,oxalate and carbamide etc,but the high cost of oxalate,low rate of production.Magnesium hydroxide in material processing(such as fire-retardant materials, paint),environmental protection(such as wastewater treatment,flue gas desulphurization),medical and public health have a wide range of applications.The past 10 years,both at home and abroad on the basis of research of magnesium hydroxide and applied research is very active.Magnesium hydroxide whiskers can be widely applied as flame retardant and reinforced materials,due to their predominant characteristics,such as low surface energy,good mechanical strength and high elastic modulus.So far,the preparation of magnesium hydroxide whiskers process more complicated,such as the preparation of natural magnesite magnesium hydroxide whiskers,and more impurities.This article study on the preparation and modification of neodymium oxide and magnesium hydroxide whiskers,the primary content are:1.Nanometer-sized Nd₂O₃ were prepared by direct precipitation method with Nd(NO₃)₃ and(NH₄)₂CO₃ as raw materials.The particle size caused by the concentration of(NH₄)₂SO₄ and calcinating time and different kinds and dosage of additives was discussed,the optimal preparing condition of nanometer-sized Nd₂O₃ were proposed:adding active carbon to the 0.1mol/L neodymium nitrate solution, 0.5mol/L(NH₄)₂CO₃ as precipitator,precursors to calcine under 800°C for 3 three hours,prepared 30nm and the good dispersity nanometer-sized Nd₂O₃.Nd₂O₃ was used as catalyst to synthesize n-butyl acetate,the reaction time was shorter and Nd₂O₃ could be reused, it indicated that the react time is short and the Nd₂O₃ can be reused.2.In order to searching new method to prepare nanometer-sized Nd₂O₃,this article used Nd(NO₃)₃ and ammonium tartrate as raw materials to prepare nanometer-sized Nd₂O₃. The precursors were characterized by ATR-FTIR and DTA-TG,the complexation of Nd(NO₃)₃ and ammonium tartrat is bridge type coordination,and know the mass loss of precursors.The dimension and feature of the products were observed by SEM,the products were spherical and the size of the products was around 40nm.3.Different modifier were used to modify nanometer-sized Nd₂O₃,the experiment indicate that the modification result of stearic acid was better.The stearic acid reacted with Nd₂O₃ by chemical adsorption and chemical reaction on the surface of Nd₂O₃ through ATR-FTIR.The modification effect was influence by concentration,modification time and temperature.The best modification condition was the mole ratio of Nd₂O₃ and Stearic acid was 1 to 1,reacted under 40℃for one hour.After the modification of Nd₂O₃ the dispersity in the organic medium was increased,and expand the application area of Nd₂O₃.4.Magnesium hydroxide is the important enhanced and flame resistance material, the special feature magnesium hydroxide such as magnesium hydroxide whisker which is stronger and more affinity to materials.Thus seek after easy method to prepare magnesium hydroxide whisker become the hotspot.Magnesium hydroxide whisker prepared by hydro-thermal method with magnesium chloride and ammonia as raw materials in this article.The length-diameter ratio of magnesium hydroxide whisker is 35.To control the feature of magnesium hydroxide whisker by change reaction temperature,hydrothermal time and temperature and add crystal modifier.