Surface modification of magnesium hydroxide particles using silane coupling agent by dry process

Abstract

In order to improve the dispersion and compatibility of magnesium hydroxide (MH) when added in the polymer matrix as fillers, the surface of MH was modified by dry process using vinyltrimethoxysilane (VTMS), and the interfacial interaction between MH and VTMS was also studied. Scanning electronic microscopy, transmission electron microscopy, and X‐ray powder diffraction analyses showed that the agglomerations of MH particles were effectively relieved, and a thin layer was formed on the surface of modified MH. Fourier transform infrared spectroscopy and X‐ray photoelectron spectroscopy analyses showed that the VTMS molecules bound strongly to the surface of MH particles and chemical bond (Si―O―Mg) was formed after modification. The effect of surface modification was evaluated by contact angle, the settlement curve, and thermogravimetric analysis. The results showed that the surface of MH particles was transformed from hydrophilic to hydrophobic, with the dispersibility and the compatibility of MH particles significantly improved in the organic phase. Additionally, the thermal stability of the VTMS modified MH particles had improved significantly.