Efficient Approach to the Preparation of Flame-Retardant Nanocomposite Polymeric Materials Based on High Density Polyethylene and Magnesium Hydroxide

A novel approach to the development of nanocomposite materials based on high-density polyethylene and an inorganic flame retardant, magnesium hydroxide, via the fundamental strategy of environmental crazing of polymers has been advanced. Efficient methods for incorporation of magnesium nitrate as a precursor into mesoporous polymeric matrices have been proposed, and optimal conditions providing high-conversion in situ hydrolysis of magnesium salt to magnesium hydroxide within the confined space of mesopores of polymeric matrixes have been found. As a result of in situ hydrolysis, spherical or needle-shaped magnesium hydroxide nanoparticles are found to be uniformly distributed within the volume of the high-density polyethylene matrix. The obtained nanocomposite polymeric materials with a low content of magnesium hydroxide nanoparticles (up to 30 wt %) are characterized by reduced flammability and mechanical characteristics comparable to those of the initial polymer.