氨合成-水热改性法制备氢氧化镁阻燃剂

为了解决氢氧化镁和聚合物之间的不相容问题, 对氨合成法-水热改性处理2步法制备高分散氢氧化镁阻燃剂进行了研究,分析了常温合成温度、水热改性温度和水热改性时间对制备大晶型、低比表面积氢氧化镁阻燃剂的影响.结果表明,经过水热改性处理改变了氢氧化镁晶体的生长习性,生成了形貌规则、粒径分布均匀、分散性良好的氢氧化镁六方片状颗粒.另外通过提高氯化镁浓度和氨水过量1倍,探讨了常温合成反应的转化率,认为应该在反应原料等当量下寻求提高转化率的可行方法.

Preparation of magnesium hydroxide flame retardant via MgCl2-NH3·H2O synthesis and hydrothermal modification treatment methods

In order to solve the problem that the Mg(OH)₂ is incompatible with the polymer, the two steps reaction of high dispersive Mg(OH)₂ preparation, synthetic reaction and hydrothermal modification treatment, was studied. The effect of the synthetic reaction temperature, hydrothermal modification temperature and time was investigated for preparation of Mg(OH)₂ flame retardant with large crystalline structure and small specific surface area. The experimental results indicate that the growth direction of Mg(OH)₂ crystal is changed and the regular hexagonal plates of Mg(OH)₂ with uniform particle size and high dispersion characteristic are formed after the hydrothermal modification treatment. With the increasing MgCl₂ concentration and/or feeding excessive NH₃·H₂O, percent conversion rates of raw materials are discussed. The results show some new technologies should be studied for increasing percent conversion of raw materials when synthetic reaction is equivalent.