abstract |
A flame retardant asphalt material useful for the processing and formation of a roofing membrane includes from about 40 to about 50 parts by weight of asphalt; from about 10 to about 20 parts by weight of a copolymer; from 0 to about 5 parts by weight of polypropylene homopolymer having at least about 45 percent by weight of crystallinity; from about 10 to about 40 parts by weight of a functional filler having a decomposition temperature above the processing temperature of the material; from about 0 to about 15 parts by weight of a non-functional filler; and, from about 0.5 to about 10 parts by weight of an intumescent material. |