Preparation and surface modification of magnesium hydroxide in a cetyltrimethyl ammonium bromide/isopropanol/cyclohexane/water microemulsion

A scalable technique for controlled synthesis and surface modification of magnesium hydroxide using the microemulsion method at room temperature was studied. The magnesium hydroxide nucleation and growth were carried out in numerous identical nanoreactors formed by cetyltrimethyl ammonium bromide/isopropanol/cyclohexane/water microemulsion. The crystal structure, morphology, thermostability and surface performance of the product as flame-resistant material were investigated by X-ray diffraction, scanning electron microscopy, thermogravimetry/differential scanning calorimetry, fourier transform infrared spectroscopy and dispersion tests. The results indicated that the product had a flake structure and belonged to a hexagonal system, the highly defined nanoflakes had a uniform diameter, and the diameter size can be well controlled in the range of 40–65 nm by adjusting the ratio of water to surfactant. The thermostability analyses showed a narrowed decomposition temperature range. Furthermore, the surfactant in microemulsion was adsorbed on the particles surface, making the surface of magnesium hydroxide changed from hydrophilic to lipophilic. Therefore the reported magnesium hydroxide material has a better flame resistance and compatibility with polymer materials than conventional magnesium hydroxide.