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.

Abstract: The present invention discloses methods of making improved rubber modified asphalt cement compositions, and compositions made by the method, where the compositions are useful in paving, roofing, coating and other sealing applications. In one aspect, the method comprises combining asphalt, RVPR (or a blended mixture of asphalt and RVPR) and at least one dodecyl or tridecylbenzene sulfonic acid (SA), which can be linear (LAS) or branched (BAS), in the presence of moderate heat. After heating the resultant RMAC mixture exhibits at least one of the following: (1) an increase in softening point, (2) an increase in hardness, or (3) improved recovery from deformation. In another aspect, the invention teaches addition of at least one SA to previously manufactured RMAC to accomplish at least one of the following: (1) an increase in softening point, (2) an increase in hardness, or (3) improved recovery from deformation.

Abstract: The present invention discloses methods of making improved rubber modified asphalt cement compositions, and compositions made by the method, where the compositions are useful in paving, roofing, coating and other sealing applications. In one aspect, the method comprises combining asphalt, RVPR (or a blended mixture of asphalt and RVPR) and at least one dodecyl or tridecylbenzene sulfonic acid (SA), which can be linear (LAS) or branched (BAS), in the presence of moderate heat. After heating the resultant RMAC mixture exhibits at least one of the following: (1) an increase in softening point, (2) an increase in hardness, or (3) improved recovery from deformation. In another aspect, the invention teaches addition of at least one SA to previously manufactured RMAC to accomplish at least one of the following: (1) an increase in softening point, (2) an increase in hardness, or (3) improved recovery from deformation.