FlameRetardant HighResilience Flexible Polyurethane Foam Filled with Expandable Graphite

Expandable graphite(EG) was added to polyurethane to form flame retardant highresilience flexible polyurethane foam in onestep. Effects of EG on flexible polyurethane foam were studied. The fixation state of EG particles in the bubble and its effect on cell morphology and the burned layer of polyurethane foam were observed by means of scanning electron microscopy and optical microscopy. The effect of different EG contents on the inhibition of foam combustion were studied with verticalhorizontal burning test and LOI experiments. The density, tensile mechanical properties and compressive mechanical properties of foams with different EG contents were examined. Effects of EG on PUF were examined by thermogravimetric analysis. Results show that the increasing of the amount of EG can inhibit the droplet formation during burning and improve flame retardant property. However, adding too much of EG leads to deformation of cells and deterioration of mechanical properties.