将氢氧化钠作为沉淀剂,以无水氯化镁为原料,采用双向沉淀法制备超细氢氧化镁(MH),在制备过程中引入硅聚醚使氢氧化镁表面有机化.考察了硅聚醚的添加方式、硅聚醚的添加量、反应温度和搅拌速度等因素对氢氧化镁浆料的过滤性能的影响.利用接触角测定仪、纳米粒度及Zeta电位分析仪、傅里叶红外光谱仪、同步热分析仪等对氢氧化镁粉体的接触角、粒径、表面结构和热稳定性进行了表征.研究结果表明:在硅聚醚的添加方式为在氢氧化钠溶液中添加硅聚醚[Mg(OH)2-Ⅱ],每100 g MH中硅聚醚的添加量为3 g,反应温度为60℃,搅拌速度为800 r/min的条件下,氢氧化镁浆料的过滤性能最好,过滤速度最快为4.79×10-4 m/s;在最佳条件下制备的氢氧化镁的接触角比未改性氢氧化镁提高了6倍多;FT-IR分析证明了硅聚醚成功地吸附在氢氧化镁的表面;热分析表明了改性氢氧化镁的热稳定性明显提高.
In situ modification of superfine magnesium hydroxide with silicon polyether
Ultrafine magnesium hydroxide(MH)was prepared by two-way precipitation method using sodium hydroxide as precipitant and anhydrous magnesium chloride as raw material.In the preparation process,silicon polyether was introduced to organicize the surface of magnesium hydroxide.The effects of the addition method of silicon polyether,the addition amount of silicon polyether,the reaction temperature and the stirring speed on the filtration performance of magnesium hy-droxide slurry were investigated.The contact angle,particle size,surface structure and thermal stability of magnesium hy-droxide powder were characterized by contact angle tester,nano particle size and Zeta potential analyzer,Fourier transform infrared spectrometer and synchronous thermal analyzer.The results showed that the addition method of silicon polyether was to add silicon polyether in sodium hydroxide solution[Mg(OH)2-Ⅱ].The addition amount of silicon polyether was 3 g per 100 g MH,the reaction temperature was 60℃,and the stirring speed was 800 r/min.The filtration performance of magnesium hydroxide slurry was the best,and the fastest filtration speed was 4.79×10-4 m/s.The contact angle results showed that the contact angle of magnesium hydroxide prepared under the optimal conditions was more than 6 times higher than that of unmodified magnesium hydroxide.FT-IR analysis proved that the silicone polyether was successfully adsorbed on the surface of magnesium hydroxide.Thermal analysis showed that the thermal stability of modified magnesium hydroxide was significantly improved.
万方数据
维普
