Powder-epoxy resin/glass fabric composites with reduced flammability

Abstract

This study investigates the possible enhancement of flame resistance in powder-epoxy resin/glass fabric composites. For this purpose, the halogen-free flame retardants containing phosphorous, nitrogen and aluminium were used. The total content of the fillers did not exceed 25 wt%. The laminates assessed for flame retardancy were designed specifically to be used as components of seats in public transport. Thermal resistance of the laminates and the surfaces of partially burned composites were also examined using thermogravimetric and scanning electron microscopy/energy-dispersive x-ray spectroscopy analyses, respectively. On the basis of the obtained results, it was found that the highest flame resistance (V-0 class, minimum oxygen concentration = 35.5% and maximum average rate of heat emission = 38.5 kW/m2 at an incident heat flux of 50 kW/m2) was identified in the laminates with matrix comprising 15 wt% aluminium diethyl phosphinate and 10 wt% melamine polyphosphate. In turn, the laminates with the matrix containing ammonium polyphosphate as the main component achieved only the V-1 flammability class.