Reaction-to-Fire Properties of Wood–Polypropylene Composites Containing Different Fire Retardants

The fire retardancy behaviour of wood–polypropylene composites containing different fire retardants [melamine, zinc borate and ammonium polyphosphate (APP)] has been studied with the cone calorimetry technique. The effect of APP in combination with graphite has been also studied with a cone calorimeter test. The fire properties measured in the cone calorimeter are discussed, including the heat release rate (HRR), total heat release, effective heat of combustion, ignition time, specific extinction area, smoke production, and mass loss rate. The results of the study show that zinc borate reduces the HRR efficiently. On the basis of the study it is evident that melamine has very little influence on the flammability of a wood–polypropylene composite, but it reduces smoke formation. APP, used alone, has increased smoke production significantly, while the production of smoke as well as other fire properties have been significantly improved when both APP and graphite have been added to the composite.