New polyester resins with reduced flammability and smoke evolution capacity

Smoke evolution [in NBS chamber by the ASTM E-622-(1983) method] and ignitability (by the oxygen-index method) was investigated for glass-reinforced polyester (GRP) laminates obtained with unsaturated polyester (UP) resins containing chlorine and bromine in the chain. In these studies, the effect on the properties of such additives as Sb2O3, Al(OH)(3), MoO3, Mg(OH)(2) and melamine diphosphate in an amount up to 30 mass-% was determined. The most efficient ignition and smoke-evolution retarder of the investigated compounds was Mg(OH)(2), whereas an essential reduction in smoke evolution was observed also with MoO3. GRP laminates with these additives meet the fire-safety recommendations concerning smoke evolution from materials used in transportation means and in the building industry. (C) 1998 John Wiley & Sons, Ltd.