Flame retardant effects of magnesium hydroxide

Magnesium hydroxide has all the characteristics required for use as a flame retardant filler. It can be made synthetically with high purity and in a range of useful morphologies, responds well to surface modifiers and decomposes endothermically with release of water at temperatures close to those of polymer degradation and high enough to allow incorporation into most polymer types. Crystal growth is difficult and, until recently, particles with suitable morphologies were too expensive for other than niche applications. New production methods are now available that offer the prospect of improved morphology control and better cost effectiveness. Use of this filler enables high levels of flame retardancy to be achieved in a wide range of polymer types, including ethylene vinyl acetate, polypropylene and polyamides. (C) 1996 Elsevier Science Limited