Klaus Rathberger, George H. Luh, presented applications of expandable graphite as a PIN flame retardant. See also AMI FR conference 2016 in pinfa Newsletter n° 61. Expandable graphite can be an effective flame retardant at 15-20% loading, either blended into polymers or applied as a surface coating, as well as being used in fire-protective coatings for structures, on textiles, on roof covering bitumens, in foams or in fire seals.
Different grades offer expansion of 50x – 350x for different applications. Applications today include polyurethane foams in aircraft seats, polyurethane and polystyrene building insulation foams, automobile interior linings, special graphites for conductive applications. An issue is that some low quality expandable graphites on the market contain significant levels of chromium as an oxidising agent.