以轻烧氧化镁制备六角片状氢氧化镁的研究

以盐湖产不同粒径轻烧氧化镁为原料,通过水化水热法制备六角片状氢氧化镁。考察了不同的反应温度、反应时间、搅拌速度和固液比对氧化镁水化率、制得氢氧化镁形貌、粒径的影响。采用X射线衍射仪、扫描电子显微镜、激光粒度仪等对所制得的氢氧化镁颗粒的物相、形貌和粒度进行了分析,同时把不同原料所得氢氧化镁用在聚乙烯（PE）中检测其阻燃性能。结果表明通过控制反应温度、反应时间、搅拌速度和固液比,氧化镁原粉的水化率可以达到95%,氧化镁细磨粉的水化率可达到100%,得到的氢氧化镁均呈现六角片状,但粒径尺寸存在差异。用在PE中,细粒径的氢氧化镁分散性更好,阻燃效果更明显。

Study on preparation of hexagonal plates of magnesium hydroxide by light-burned magnesium oxide

Hexagonal plates of magnesium hydroxide was prepared from salt lake light-burned magnesia with different grain size by hydration-hydrothermal method.The influence of reaction temperature,reaction time,stirring rate and solid-liquid ratio on the conversion rate of magnesia,the morphology and particle size of magnesium hydroxide was investigated systematically. The phase,morphology and particle size of magnesium hydroxide were investigated by X-ray diffraction（XRD）,scanning electronic microscope（SEM）,and laser particle size analyzer（LPSA） respectively.Meanwhile,magnesium hydroxide from di-fferent raw materials was added in PE to test its flame retardancy.The results showed that by controlling the reaction tempera-ture,reaction time,stirring speed and solid-liquid ratio,the hydration rate of magnesium oxide raw powder could reach 95%,the hydration rate of magnesium oxide fine grinding powder could reach 100%,and the obtained magnesium hydroxide was both hexagonal,but the particle size was different.When it was used in PE,fine-grained magnesium hydroxide had better dispersion and more obvious flame retardant performance.