NaAl(OH)2CO3阻燃晶须的水热合成及其阻燃性能

Hydrothermal synthesis and flame-retardant properties of NaAl(OH)_2CO_3 whiskers

以异丙醇铝和NaHCO3为原料,采用水热法制备了片钠铝石(NaAl(OH)2CO3)晶须,通过XRD、SEM对不同水热条件下合成产物的物相和形貌进行了表征。结果表明,制备的NaAl(OH)2CO3晶须长度为10～20μm,长径比为20～40;初始反应体系的pH值、反应物Na/Al摩尔比、反应温度和反应时间对产物的生长、形貌及尺寸分布有显著影响。添加40%(质量分数)NaAl(OH)2CO3晶须的阻燃EVA,极限氧指数为33.5,垂直燃烧达FV-1,说明NaAl(OH)2CO3晶须具有良好的阻燃性能。

NaAl（OH）2CO3 whiskers were synthesized by hydrothermal method using aluminium isopropoxide which was prepared in lab freshly and NaHCO3. Their crystalline structure and morphology were characterized by XRD and SEM. The results indicate that the NaAI（OH）2CO3 whiskers possess particle length of 10-20μm, aspect ratio （length to diameter） of 20-40 respectively, and good distribution. The influences of acidity of the reaction medium, starting materials, reaction temperature and reaction time on the phase composition and morphologies of NaAl（OH）2CO3 whiskers are significant. The studies of NaAl（OH）2CO3/EVA compounds show that when the content of NaAl（OH）2CO3 in EVA is 40M, the LOI of the compounds increases to 33.5 and UL- 94 reaches FV-1 grade, NaAI（OH）2CO3 whiskers are of fine flame-retardant properties.