Effect of expandable graphite on flammability of polystyrene foams

The effects of expandable graphite (GIC) on the flammability of polystyrene (PS) foams are investigated. Through these investigations, the effects of lignin surfactants, mesh size and GIC concentration in matrix and synergistic effect of triphenyl phosphate on the flammability of PS foams are studied. The flame test results showed that lignin surfactant increases the flammability resistance of foams. Also it was shown that increasing the mesh size improves the resistance of foam but destroys the foam cells so that the best mesh size was chosen for 300 micron which had the best foam cell and flame resistance is proved by optical microscope. Specifically, we observed a complete inflammability in 10% of the samples. Finally, the synergistic effect of triphenyl phosphate was checked where the presence of only 6% of both triphenyl phosphate and GIC in foam formulations make the foam complete inflammable.

Keywords:

expandable graphite , polystyrene foam , Flame retardant