Patent ID: 7186765

Claim:
A method for preparing asphalt and polymer compositions comprising: heating the asphalt in a stirred tank to a temperature sufficient to allow stirring of the asphalt in the tank, wherein said temperature is at least 330° F.; adding an elastomeric polymer to the tank in an amount not greater than twelve percent by weight of the total composition to form a mixture; adding a crosslinking composition to the composition; continue stirring and maintain the temperature in the tank for at least forty-five minutes, wherein the crosslinking composition consists essentially of at least 0.08 to 0.3 percent by weight based on the asphalt of 2-mercaptobenzothiazole, from 0.08 to 0.3 percent by weight based on the asphalt of elemental sulfur, and at least 0.04 to 0.15 percent by weight based on the asphalt of zinc oxide.