Mg(OH)₂/polystyrene Hybrid Nanocomposite Particles Prepared by Emulsion Polymerization

Abstract

Core-shell type Mg(OH)2/polystyrene nanocomposite particles were prepared by the emulsion polymerization of styrene in the presence of surface-functionalized Mg(OH)2 particles. Platelet-like, 80 nm Mg(OH)2 particles were previously functionalized with 3-(trimethoxysilyl)propyl methacrylate and used for the polymerization to produce stable hybrid composite latexes. Polyencapsulation of the Mg(OH)2 particles in polystyrene matrix took place when the reaction was conducted with 10 to 30% w/w of Mg(OH)2 with respect to the monomer. With 40% loading of Mg(OH)2, an unstable latex having aggregated particles was produced. Transmission electron microscopic images revealed the hybrid composites to be multi-core/shell type encapsulated particles, while thermogravimetric analysis showed that a difference in the decomposition onset temperature of polystyrene was not apparent in the range of 0 to 40% content of nano-Mg(OH)2.