摘要:
It has been discovered that a synthetic flux oil can contain and deliver asphaltites, such as gilsonite, more easily and readily to an asphalt to improve its properties. The synthetic flux oil includes the asphaltite and a carrier oil. Depending on the nature of the carrier oil, the synthetic flux oil may or may not need to be heated during mixing and incorporation into the asphalt.
摘要:
The present invention provides a method for preparing an asphalt and thermoplastic elastomer composition. The process comprises heating an asphalt cut in a stirred tank to a temperature sufficient to allow the stirring of the asphalt in the tank. A thermoplastic elastomer or rubber is added to the asphalt while continuing to stir the asphalt. The mixture is stirred at a speed and for a period of time sufficient to increase the distribution of the elastomer into the asphalt. The stirring speed is reduced and the temperature is increased to add crosslinking agents to the tank. Stirring is continued for a period of time sufficient to improve the distribution of the crosslinking agent dispersion in the asphalt. Crosslinking agents include compositions of mercaptobenzothiazole, zinc oxide and elemental sulfur; compositions of mercaptobenzothiazole, zinc oxide, and mixed polythiomorpholine; and compositions of zinc 2-mercaptobenzothiazole and dithiodimorpholine.
摘要:
It has been discovered that divalent metal oxides other than zinc oxide (ZnO) perform equivalently as activators in preparing asphalt polymer compositions. Typically, the crosslinker in these compositions is sulfur. Divalent metal oxides such as cupric oxide (CuO), magnesium oxide (MgO), and calcium oxide (CaO) provide alternative activators to give versatility to designing asphalt polymer compositions. In addition, some of these alternative divalent metal oxides are less expensive than the traditionally used ZnO.
摘要:
Asphalt and elastomeric polymer compositions crosslinked with mixed polythiomorpholines or at least one alkyl polysulfide can give polymer modified asphalts (PMAs) with improved properties and/or reduced H2S evolution. When at least one alkyl polysulfide is used to completely or partially replace conventional crosslinkers such as S or MBT, mercaptobenzimidazole (MBI) may be optionally used as a co-crosslinker. The use of mixed polythiomorpholines as crosslinkers provide PMAs with better low temperature profiles (BBR m-values). The use of at least one alkyl polysulfide crosslinker gives PMAs with improved PAV-aged DSR results, and reduced H2S evolution. The use of at least one alkyl polysulfide crosslinker together with MBI may give PMAs with improved PAV DSR Fail Temperatures.
摘要:
An asphalt material having improved paving characteristics and processes for its preparation. An asphalt base material is heated in a mixing chamber to a temperature sufficient to melt the asphalt so that it can be stirred. A water-insoluble heavy metal soap is incorporated into the chamber in an amount effective to reduce the PAV-DSR temperature of the asphalt base material by an incremental amount of at least 1° C. Thereafter, the asphalt material is recovered from the mixing chamber to provide an asphalt product containing the heavy metal soap which exhibits a PAV-DSR temperature which is less than the PAV-DSR temperature for the corresponding base material without the addition of the heavy metal soap. The water-insoluble soap is a C14-C18 heavy metal soap such as a C16-C18 zinc- or calcium-based soap including zinc stearate, zinc oleate and zinc palmitate. The heavy metal soap is added to the mixing chamber in an amount within the range of 0.05-3.0 wt. % of the amount of asphalt based material in the mixing chamber. A thermoplastic polymer may be added to the asphalt based material to provide a polymer-modified asphalt blend. An asphalt paving composition comprising an asphalt base material and a water-insoluble heavy metal soap in an amount to provide a PAV-DSR temperature lower than the PAV-DSR temperature of the corresponding asphalt material without the addition of the heavy metal soaps.
摘要:
An asphalt material having improved paving characteristics and processes for its preparation. An asphalt base material is heated in a mixing chamber to a temperature sufficient to melt the asphalt so that it can be stirred. A water-insoluble heavy metal soap is incorporated into the chamber in an amount effective to reduce the PAV-DSR temperature of the asphalt base material by an incremental amount of at least 1° C. Thereafter, the asphalt material is recovered from the mixing chamber to provide an asphalt product containing the heavy metal soap which exhibits a PAV-DSR temperature which is less than the PAV-DSR temperature for the corresponding base material without the addition of the heavy metal soap. The water-insoluble soap is a C14-C18 heavy metal soap such as a C16-C18 zinc- or calcium-based soap including zinc stearate, zinc oleate and zinc palmitate. The heavy metal soap is added to the mixing chamber in an amount within the range of 0.05-3.0 wt. % of the amount of asphalt based material in the mixing chamber. A thermoplastic polymer may be added to the asphalt based material to provide a polymer-modified asphalt blend. An asphalt paving composition comprising an asphalt base material and a water-insoluble heavy metal soap in an amount to provide a PAV-DSR temperature lower than the PAV-DSR temperature of the corresponding asphalt material without the addition of the heavy metal soaps.
摘要:
An asphalt/aggregate composition having enhanced adhesion characteristics and its preparation. An asphalt base material is heated to a molten state in order to permit mixing of the asphalt with added components. A heavy metal soap is incorporated into the asphalt base material to enhance the adhesion of the asphalt base material with an aggregate component which is mixed with the asphalt base material to provide an asphalt/aggregate blend. The asphalt and aggregate can be blended together in a mixing chamber to provide a fluid asphalt/aggregate concrete which is then dispensed on a substrate surface or the asphalt base material and aggregate components can be separately applied to the substrate surface to provide the ultimate asphalt/aggregate concrete. The heavy metal soap is a C14-C18 heavy metal soap such as zinc stearate. Zinc oxide may also be added to the asphalt base material in an amount which is less than the amount of zinc stearate. The asphalt base material may be polymer-modified asphalt and may incorporate a crumb rubber component to provide a rubber-modified asphalt.
摘要:
Methods of modifying crude fractions are described herein. The methods generally include blending a crude fraction with an emissions reducing additive to form a modified crude fraction, wherein the modified crude fraction exhibits reduced sulfur emissions. The emissions reducing additive generally includes a dispersion of a metal oxide.
摘要:
Asphalt and elastomeric polymer compositions crosslinked with mixed polythiomorpholines or at least one alkyl polysulfide can give polymer modified asphalts (PMAs) with improved properties and/or reduced H2S evolution. When at least one alkyl polysulfide is used to completely or partially replace conventional crosslinkers such as S or MBT, mercaptobenzimidazole (MBI) may be optionally used as a co-crosslinker. The use of mixed polythiomorpholines as crosslinkers provide PMAs with better low temperature profiles (BBR m-values). The use of at least one alkyl polysulfide crosslinker gives PMAs with improved PAV-aged DSR results, and reduced H2S evolution. The use of at least one alkyl polysulfide crosslinker together with MBI may give PMAs with improved PAV DSR Fail Temperatures.
摘要翻译:用混合多硫代吗啉或至少一种烷基多硫化物交联的沥青和弹性体聚合物组合物可以得到具有改进性能和/或降低的H 2 S 2 S演化的聚合物改性沥青(PMA)。 当使用至少一种烷基多硫化物来完全或部分替代常规交联剂如S或MBT时,巯基苯并咪唑(MBI)可以任选地用作共交联剂。 使用混合的聚硫代吗啉作为交联剂为PMA提供了更好的低温谱(BBR m值)。 使用至少一种烷基多硫化物交联剂使得PMA具有改进的PAV老化的DSR结果和降低的H 2 S 2 S进化。 使用至少一种烷基多硫化物交联剂与MBI一起可以使PMA具有改进的PAV DSR失败温度。
摘要:
In methods of preparing asphalt and elastomeric polymer compositions such as polymer modified asphalt (PMA), it has been discovered that the compatibility can be improved by adding excess amounts of certain organic and inorganic metal salts beyond the proportions normally used. Suitable metal salts may be metal oxides that include, but are not necessarily limited to, zinc oxide, calcium oxide, and the like. The method of the invention also permits asphalt modified with other polymers such as ground tire rubber (GTR) to have improved compatibility. Additionally, the use of excess amounts of these metal salts helps control gel formation.