| abstract |
A halogen-free flame-retardant bitumen composition with improved performance characteristics is described. The flame-retardant bitumen composition contains at least 45 weight percent bitumen, about 2 to 25 weight percent thermoplastic polymer, and about 15 to 35 weight percent of a mixture of flame-retardant compounds. The mixture of flame-retardant compounds comprises alumina trihydrate and/or magnesium hydroxide, at least 2 weight percent zinc borate, and, optionally, about 2 to 20 weight percent calcium carbonate of the final flame-retardant bitumen composition. |