超重力技术制备纳米氢氧化镁阻燃剂的应用研究

Preparation of nano-sized magnesium hydroxide as a flame retardant by high gravity technology and its application

本文采用超重力技术制备纳米氢氧化镁阻燃剂并对其进行湿法表面改性,应用TEM、XRD、BET、吸油值、沉降速度等方法对改性前后的纳米氢氧化镁粉体进行了分析和表征,将改性前后的纳米氢氧化镁应用到软质PVC体系中。实验结果表明:超重力技术制备的纳米氢氧化镁的粒径为70nm,为六方形片状;经不同改性剂改性的粉体中,以硬脂酸锌改性粉体的应用效果较好;未改性纳米氢氧化镁的比表面为21.5760m2/g,而改性粉体的比表面为22.0641m2/g,有一定程度的增大;改性氢氧化镁的沉降速度减慢,吸油值下降,添加量为40份时PVC体系的综合性能较好。

The preparation of nano-sized magnesium hydroxide (NSMH) by high gravity method and surface modification of such made NSMH were investigated in this paper. Different kinds of surface modifiers were used in magnesium hydroxide filled in flexible PVC to improve the flame retardance and mechanical properties. The morphology and the dispersion of the particles were characterized by TEM, XRD, BET techniques. The experimental results showed that the mean size of NSMH was 70 nm and its BET area was 22.0641 m^2/g, which was larger than that of unmodified NSMH. According to the speed of sedimentation and oil absorption of NSMH, it could be inferred that modified NSMH had a better dispersion in organic media and it could improve the flame retardation of flexible PVC remarkably, and zinc stearate had a better modification effect compared with other modifiers. When 40 copies MNMH were added into flexible PVC, it exhibited much better in both flame retardance and mechanical properties.