Fire retardant behaviour of halogen-free calcium-based hydrated minerals

The flame retardant effect of hydrated lime, partially and completely hydrated dolomitic limes in polyethylene and ethylene vinyl acetate copolymers was evaluated and compared to that of magnesium hydroxide and aluminium hydroxide. An important decrease of the peak of heat release rate as measured by cone calorimeter test was observed for Ca-based composites. Thermogravimetric and X-Ray Diffraction analysis indicated that the calcium hydroxide fraction plays an important role in the generation of an intumescent mineral residue during the combustion.