【摘要】 以MgCl2.6H2O和NH3.H2O为原料,乙醇和吐温80为分散剂,采用均匀沉淀法制备氢氧化镁,经水洗、醇洗、干燥、煅烧得到纳米氧化镁粉体。实验确定制备纳米氧化镁的工艺条件为:反应配比MgCl2.6H2O∶NH3.H2O(摩尔比)为1∶2,反应温度45℃,反应时间40 min,陈化时间2 h,氢氧化镁在900℃下煅烧3 h。以亲油化度为考察指标,通过单因子实验和正交实验,确定了纳米氧化镁表面改性的最佳工艺条件为:硬脂酸0.02 g,改性温度80℃,改性时间2 h.在优化条件下,改性后的纳米氧化镁的亲油化度达到27.7%.用透射电镜(TEM)对改性前后的纳米氧化镁粉体进行了表征,TEM表明所制备的样品为纳米级,改性前后氧化镁粒子尺寸基本没有变化,但改性后的纳米氧化镁分散性明显变好.更多还原

【Abstract】 With MgCl₂·6H₂O and NH₃·H₂O as raw materials,C₂H₅OH and Twee-80 as dispersing agent,the magnesium hydroxide is prepared by homogeneous precipitation method.Nanometer magnesium oxide was obtained by water wash、alcohol wash、dring and calcination.The results indicate that the optimum technological conditions are as follows: their molar ratio of reactants is（MgCl₂·6H₂O∶（NH₃·H₂O））=1∶2,temperature of reactants is 45 ℃,time of the reaction is 40 min,aging time 2 h,the calcination temperature 900 ℃ and the calcination time 3 h.The paper takes oil-absorbed value as the inspection target,utilizes the single factor experiment and the orthogonal experiment to obtain nanometer magnesium optimum surface modification condition: the stearic acid is 0.02 g,the modification temperature is 80 ℃,and the modification time is 2 h.Under the optimized condition and after modification nanometer magnesium oxide oil-absorbed value achieves 27.7%.The surface characterization of MgO was investigated by means of TEM.TEM shows that the size of the modified MgO is the same as that of the unmodified MgO.However,nanometer magnesium oxide dispersivity improves obviously after modification.更多还原