Jianxing GENG from the CAS Technical Institute of Physics and Chemistry and colleagues have developed a non-burning polyimide foam that is strong enough to support a beaker of liquid weighing 6kg, but light enough to balance on a rose. Its flame-retardant properties come from 2% of red phosphorus-hybridised graphene produced by ball milling. The tiny phosphorus particles oxidise quickly when heated and promote char formation. Combined with graphene platelets, which are chemically stable even at high temperatures, the material forms an oxygen-proof layer on the surface. This stops the underlying material from burning.
CAS news release, August 15, 2017