Abstract: Non thixotropic, aqueous emulsions prepared from rubber modified asphalt cement (RMAC). The RMAC is prepared by a method whereby recycled tire rubber is liquified or otherwise consumed by or incorporated into asphalt such that no more than 2% by weight of solid particulate rubber remains. The RMAC may be emulsified in an aqueous or partially aqueous emulsification solution using a one-step or multi-step emulsification process. These aqueous RMAC emulsions are useable in many applications including paving, seal coat, roofing and slurry seal applications.

Abstract: Cationic aqueous emulsions of rubber modified asphalt cement (RMAC) useable for paving, seal coat, slurry seal, roofing, coating and other applications. First, a RMAC is prepared by combining 45 to 90% by weight asphalt with about 5% to about 55% by weight solid recycled rubber (e.g., crumb rubber from used vehicle tires) under conditions that cause at least a substantial portion of the solid rubber to become liquified or otherwise incorporated into the asphalt. The RMAC may be treated with dodecyl benzenesulfonic acid (DDBSA) which causes reaction(s) to occur and results in a lowering of the viscosity of the RMAC. The RMAC (or DDBSA-treated RMAC) may then be emulsified in an aqueous medium to provide an aqueous emulsion.