Asphalt binder performance additive

Abstract

Additives for an asphalt binder composition for lowering the minimum temperature at which cracking may occur in a binder are described. The asphalt binder composition includes a binder and the additive that lowers the temperature at which the asphalt binder composition may be used while maintaining flexibility. The asphalt binder composition may be useful in colder climates.

Description

ASPHALT BINDER PERFORMANCE ADDITIVECROSS-REFERENCE TO RELATED APPLICATION

[0001] This application claims the benefit of U.S. Provisional Patent Application Serial No. 63 / 664,047 filed June 25, 2024. The content of the aforementioned application is incorporated herein by reference.STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

[0002] Not applicable.TECHNICAL FIELD

[0003] The present disclosure relates to additives for enhancing the performance of asphalt and asphalt binders.BACKGROUND

[0004] Asphalt pavement, also known as asphalt concrete or blacktop, serves as a ubiquitous and essential component of modern transportation infrastructure. Asphalt pavement provides a durable and smooth surface for roads, highways, parking lots, driveways, and various other paved areas.

[0005] Asphalt pavement includes asphalt, which may also be referred to as asphalt binder or bitumen. Asphalt is a sticky, black, and highly viscous liquid or semi-solid form of petroleum that serves as the binding agent that holds together the aggregates in asphalt pavement. Asphalt, a complex mixture of hydrocarbons derived from crude oil refining, serves as a primary component in road construction and maintenance due to its versatility, durability, and cost-effectiveness. The performance of asphalt binders under various environmental and loading conditions can be limited, leading to issues such as rutting, cracking, and aging.

[0006] Traditional asphalt binders are classified based on their performance grades, which are determined by their rheological properties at specific temperatures. The concept of performance grading was developed by the Strategic Highway Research Program (SHRP) in the United States in the 1990s. SHRP introduced the Superpave (Superior Performing Asphalt Pavements) system to facilitate asphalt binder specification and testing.

[0007] Performance-graded (PG) asphalt binders indicate that a binder meets certain rheological properties at a specified temperature range. The performance grades consist of two parts: the high-temperature performance grade (PG High) and the low-temperature performance grade (PG Low). The PG designation is followed by two numbers representing the expected pavement temperature range in degrees Celsius, at which the binder will perform adequately.

[0008] High-Temperature Performance Grade (PG High): This parameter indicates a binder’s resistance to rutting and deformation under high-temperature conditions, such as those experienced in warm climates or under heavy traffic loads. Binders with higher PG High grades exhibit greater stiffness at high temperatures.

[0009] Low-Temperature Performance Grade (PG Low): This parameter indicates a binder’s ability to remain flexible and resist cracking at low temperatures, such as those encountered during winter or in cold regions. Binders with higher PG Low grades remain more flexible at low temperatures without becoming brittle.

[0010] One example of a performance-graded asphalt binder commonly used in road construction is PG 64S-22. In this designation, “PG 64” refers to the high-temperature performance grade, indicating that the binder is designed to withstand high temperatures without significant deformation or rutting. The “64” indicates the maximum pavement temperature in degrees Celsius that the binder can withstand while resisting rutting. The “S- 22” designation specifies the low-temperature performance grade, signifying that the binder remains sufficiently flexible at low temperatures to resist cracking. The “-22” indicates the minimum pavement temperature in degrees Celsius that the binder can endure without becoming too brittle and cracking. The length of time that the binder can withstand the temperatures may be an average of 7 days. The “S” stands for “Standard” traffic, indicating that the binder is suitable for typical road traffic conditions.

[0011] The number of performance grades in the Superpave system can vary depending on the specific requirements of a project or region. Theoretically, high-temperature performance grades may include PG 46, PG 52, PG 58, PG 64, PG 70, PG 76, PG 82, and PG 88, and low- temperature performance grades may include PG -4, PG -10, PG -16, PG -22, PG -28, PG -34, PG -40, PG -46, PG -52, PG -58, and PG -64. However, common grades include PG 58, PG 64, PG 70, PG 76, and PG 82 for high-temperature performance, and PG -22 and PG -28 for low-temperature performance. In the Superpave system, the combinations of high-temperature and low-temperature performance grades are used to specify the properties of asphalt binders.

[0012] There are several challenges with PG asphalt binders including, but not limited to the following. Temperature Sensitivity: PG asphalt binders exhibit varying degrees of stiffness and viscosity at different temperatures, which can affect their performance under dynamic loading and thermal cycling. Aging and Oxidation: Exposure to environmental factors such as sunlight, oxygen, and moisture leads to binder aging and oxidative degradation, compromising its mechanical properties and durability over time. Rutting and Cracking: Inadequate resistance to permanent deformation (rutting) and fatigue cracking limits the service life of asphalt pavements, especially in high-traffic areas and regions with extreme climatic conditions.

[0013] To overcome these challenges and enhance the performance of PG asphalt binders, there is a growing demand for innovative additives capable of improving rheological properties to enhancing the viscosity-temperature relationship of asphalt binders to achieve optimal performance across a wide temperature range, including high-temperature stability and low- temperature flexibility; enhancing aging resistance to mitigate the effects of oxidative aging and environmental degradation to maintain binder properties and extend pavement service life; and increasing resistance to rutting and cracking by reinforcing the binder-aggregate matrix to improve resistance to permanent deformation and fatigue cracking under heavy traffic and harsh environmental conditions.SUMMARY

[0014] The present disclosure addresses the aforementioned challenges by providing novel asphalt additives specifically formulated to modify the properties of asphalt binders. These additives are designed to enhance binder rheology, aging resistance, and mechanical performance, thereby improving the overall durability, longevity, and sustainability of asphalt pavements. Through rigorous experimentation and optimization, the proposed additives offer a cost-effective solution for achieving superior performance in asphalt pavements.

[0015] A crack-resistant asphalt binder composition may include a synergistic combination of an asphalt binder being crack resistant at a temperature of -22 degrees Celsius and an additive having a flash point greater than 300 degrees Fahrenheit. The additive may include a compound including an alkyl-substituted monoaromatic or unfused polyaromatic compound or a comb polymer. The synergistic combination may result in the crack-resistant asphalt composition being crack resistant below the temperature.

[0016] A method for preparing a crack-resistant asphalt binder composition may include combining an asphalt binder that is crack resistant at a temperature of -22 degrees Celsius withan additive comprising an alkyl-substituted monoaromatic or unfused polyaromatic compound to produce the crack-resistant asphalt binder composition being crack resistant below the temperature of -22 Celsius.

[0017] A method for preserving a surface may include providing a crack-resistant asphalt binder composition with a synergistic combination of an asphalt binder being crack resistant at a temperature of -22 degrees Celsius and an additive comprising an alkyl-substituted monoaromatic or unfused polyaromatic compound, where the synergistic combination results in the crack-resistant asphalt composition being crack resistant below the temperature of -22 degrees Celsius; mixing the asphalt binder composition with aggregate material to produce an asphalt mixture; and placing the mixture onto the surface.BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The disclosure can be understood in consideration of the following detailed description of various embodiments in connection with the accompanying drawings.

[0019] FIG. 1 shows the continuous grading of binder-A300 additive blends.

[0020] FIG. 2 shows the high-temperature performance grade and reduction for binder- A300 Additive blends.

[0021] FIG. 3 shows the low-temperature performance grade and reduction for Binder- A300 additive blends.

[0022] FIG. 4 shows ATc values of binder- A300 additive blends.

[0023] FIG. 5 shows the Glover-Rowe parameters of Modulus G* and Phase Angle for binder- A300 additive blends.

[0024] FIG. 6 shows the R-value for binder- A300 additive blends.

[0025] FIG. 7 shows the continuous grading for different binder-additive blends.

[0026] FIG. 8 shows the PG intermediate G* sind and phase angle for each additive in the base binder at 3 wt%.

[0027] FIG. 9 shows the ATc for the base binder and the three additive blends.

[0028] FIG. 10 shows the rotational viscosity values at 135C0for the binder-3 wt% additive blend.

[0029] FIG. 11 shows the continuous grading, RTFOT, and PAV results of the 225 additive.

[0030] FIG. 12 shows the continuous grading, RTFOT, and PAV results of the 250 additive.

[0031] FIG. 13 shows the continuous grading of binder- A300 additive blends.

[0032] FIG. 14 shows the high-temperature performance grade and reduction for binder-4800 Additive blends.

[0033] FIG. 15 shows the low -temperature performance grade and reduction for binder-4800 additive blends.

[0034] FIG. 16 shows ATc values of binder-4800 additive blends.

[0035] FIG. 17 shows the Glover-Rowe parameters of Modulus G* and Phase Angle for binder-4800 additive blends.

[0036] FIG. 18 shows the R-value for binder-4800 additive blends.DETAILED DESCRIPTION

[0037] The present disclosure is generally directed to an asphalt additive as defined herein. When added to an asphalt binder composition containing asphalt, the asphalt additive not only can lower the viscosity of the asphalt binder composition but also improve other properties, for example, lowering the low-temperature grade or the minimum temperature at which the asphalt binder composition is susceptible to cracking as by the cracking property Delta T Critical (ATc). For example, the asphalt additive may provide a half grade reduction in both high and low temperature grade while minimally affecting the cracking property ATc. The asphalt additive may also lower shear strain and stiffness thereby providing a more flexible asphalt.

[0038] For purposes of promoting an understanding of the principles of the disclosure, reference will now be made to the embodiments illustrated in the drawings, and specific language will be used to describe the same. It will nonetheless be understood that no limitation of the scope of the disclosure is intended by the illustration and description of certain embodiments of the disclosure. In addition, any alterations and / or modifications of the illustrated and / or described embodiment(s) are contemplated as being within the scope of the present disclosure. Further, any other applications of the principles of the disclosure, as illustrated and / or described herein, as would normally occur to one skilled in the art to which the disclosure pertains, are contemplated as being within the scope of the present disclosure.

[0039] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present disclosure belongs.

[0040] The phrases “in one embodiment”, “according to one embodiment” and the like generally mean the particular feature, structure, or characteristic following the phrase is included in at least one embodiment of the present disclosure and may be included in more than one embodiment of the present disclosure. Importantly, such phrases do not necessarily refer to the same embodiment. If the specification states a component or feature “may,” “can,”“could,” or “might” be included or have a characteristic, that particular component or feature is not required to be included or have the characteristic.

[0041] Where a range of values is provided, it is understood that each intervening value, to the tenth of the unit of the lower limit unless the context clearly dictates otherwise, between the upper and lower limit of that range and any other stated or intervening value in that stated range, is encompassed within the present disclosure. The upper and lower limits of these smaller ranges may independently be included in the smaller ranges and are also encompassed within the present disclosure, subject to any specifically excluded limit in the stated range. Where the stated range includes one or both of the limits, ranges excluding either or both of those included limits are also included in the present disclosure.

[0042] The term “about” used throughout is used to describe and account for small fluctuations. For instance, “about” may mean the numeric value may be modified by ±5%, ±4%, ±3%, ±2%, ±1%, ±0.5%, ±0.4%, ±0.3%, ±0.2%, ±0.1% or ±0.05%. All numeric values are modified by the term “about” whether or not explicitly indicated. Numeric values modified by the term “about” include the specific identified value. For example, “about 5.0” includes 5.0.

[0043] The term “asphalt” (i.e., bitumen) is used in its conventional sense to include the natural or manufactured black or dark-colored solid, semi-solid or viscous material composed mainly of high molecular weight hydrocarbons derived from a cut in petroleum distillation after naphtha, gasoline, kerosene, and other fractions have been removed from crude oil. Asphalt constituents may include oils, resins, and asphaltenes. Oils are the light fraction, having molecular weights in the range of 24 to 800. Resins are the more polar fraction, having molecular weights in the range of 800-2000. Asphaltenes are high molecular weight molecules (1800-8000) and possess aromatic rings. An average asphalt has a ratio of asphaltenes / resins / oil by weight of approximately 23 / 27 / 50. Harder asphalt has correspondingly higher ratios of asphaltenes to resins and oil. The asphalt may be virgin asphalt or reclaimed asphalt.

[0044] The term “aggregate” refers to particulate mineral material including, but not limited to, limestone, granite, trap rock, gravel, crushed gravel sand, crushed stone, crushed rock, slag, and mixtures thereof.

[0045] The term “Performance Grade” (PG) refers to the temperature interval for which a specific asphalt product is designed. For example, an asphalt product designed to accommodate a high temperature of 64°C and a low temperature of -22°C. has a PG of 64-22.Performance Grade standards are set by the National Committee of Highway and Roadway Professionals. A change of 6 degrees Celsius represents a change in grade; a half-grade reduction is a reduction in temperature by 3 degrees Celsius. For example, a change in low- temperature grade from PG -22 to PG -28 represents a full grade reduction, and a change in low-temperature grade from PG -28 to PG -22 represents a full grade increase. For example, a change in high-temperature grade from PG 64 to PG 58 represents a full grade reduction, and a change in high-temperature grade from PG 64 to PG 70 represents a full grade increase. For high-temperature grade, if the maximum high temperature of the binder is between a lower number (e.g., 70) and a higher number (e.g., 76), the high-temperature grade of the binder is the lower number (e.g., 70). For low-temperature grade, if the minimum low temperature of the binder is between a lower number (e.g., -34) and a higher number (e.g., -28), the low- temperature grade of the binder is the higher number (e.g., -28). This ensures that the binder meets at least the standard of the high-temperature grade and the low-temperature grade.

[0046] The terms “preferred” and “preferably” refer to embodiments that may afford certain benefits, under certain circumstances. However, other embodiments may also be preferred, under the same or other circumstances. Furthermore, the recitation of one or more preferred embodiments does not imply that other embodiments are not useful and is not intended to exclude other embodiments from the scope of the present disclosure.

[0047] The term “optional” or “optionally” means that the subsequently described event or circumstance may or may not occur, and that the description includes instances where said event or circumstance occurs and instances where it does not.

[0048] The described crack-resistant asphalt composition includes a synergistic combination of a binder and at least one additive or at least one modifier. In some examples, the crackresistant asphalt composition includes a binder and at least two additives or modifiers. An additive is a substance added to a base material (such as asphalt, polymers, fuels, coatings, etc.) to enhance or confer specific properties. A modifier is a type of additive specifically intended to alter the intrinsic properties of a material in a more targeted or fundamental way. All modifiers are additives, but not all additives are modifiers.

[0049] In the described asphalt compositions, the binder may be an unmodified (e.g., base asphalt) or modified asphalt binder. Base asphalt is the unmodified, raw asphalt material obtained from crude oil refining. Base asphalt can be used directly as a binder or further modified (e.g., modified asphalt binder) to improve its properties, such as elasticity, resistance to deformation, temperature susceptibility, and durability. A binder of any performance grade may be suitable for the asphalt composition. A binder of a performance grade of PG High-PGLow grade may have a performance grade profile of high-temperature grade of PG High to less than PG High+6 and a low-temperature performance grade of PG Low to greater than PG Low- 6.

[0050] A binder of any performance grade may include a combination of bitumen and additives. The bitumen may include asphalt cement, which may be a refined product obtained from the distillation of crude oil. Asphalt cement may provide the necessary binding properties to the binder. A binder may be unmodified (i.e., base asphalt binder without any additives or modifications) or may include at least one additive. Additives may be performance enhancing or stabilizers. Additives in a binder may include polymers, rubbers, rejuvenating agents, recycling agents, performance enhancing agents (e.g., anti-stripping agents, warm mix asphalt (WMA) agents, etc.), stabilizers (e.g., fiberglass), surfactants, a hydrocarbon oil, one or more hydrogen sulfide scavengers, one or more cross-linking agents, etc. and / or mixtures thereof. Polymers, such as styrene-butadiene-styrene (SBS) or ethylene-vinyl acetate (EVA), may improve the performance of the binder by enhancing the elasticity and temperature susceptibility of the binder. Anti-stripping agents may improve the adhesion between the binder and aggregates, reducing the risk of stripping (loss of bond) in the presence of water. Recycling agents may be added to incorporate reclaimed asphalt pavement (RAP) or reclaimed asphalt shingles (RAS) into the binder to promote sustainability. Crumb rubber derived from recycled tires may improve elasticity and resistance to thermal cracking and rutting of the binder while being environmentally conscious. A rejuvenating agent may restore the properties of aged asphalt (e.g., RAP mixes). A warm mix asphalt (WMA) agent may allow the asphalt composition to be produced and placed at lower temperatures. Adding fiber-glass fibers to the binder may improve tensile strength and resistance to cracking and deformation.

[0051] Non-limiting examples of anti-stripping agents includes lime, one or more amines, one or more phosphate esters, or any mixture thereof. Illustrative lime can include, but is not limited to, hydrated lime, quick lime, dolomitic lime, or any mixture thereof. Illustrative amines can include, but are not limited to, polyamines, amidoamines, or a mixture thereof. Suitable amines can include, but are not limited to, tallow diamine, tallow triamine, bishexamethylenetriamine, triethylenepentamine, or any mixture thereof.

[0052] Examples of surfactants include, but are not limited to amines, diamines, polyamines, ethoxylated amines, ethoxylated alkyl diamines, ethoxylated alkyl polyamines, amido amines, amidopolyamines, imidazolines, any of their corresponding organic or inorganic salts, or any mixture thereof.

[0053] The hydrocarbon oil can be or include a wide range of hydrocarbon oils. The hydrocarbon oil can be or include one or more hydrocarbon oils recovered from the distillation or fractionation of crude oil between number 2 diesel fuel oil and vacuum tower bottoms, one or more hydrocarbon oils recovered from the distillation or fractionation of a fluid catalytic cracker product, or any mixture thereof. Illustrative hydrocarbon oils can include, but are not limited to, gas oil, naphtha, number 3 fuel oil, number 4 fuel oil, number 5 fuel oil, number 6 fuel oil and mixtures thereof.

[0054] Examples of hydrogen sulfide scavengers can include, but are not limited to, zinc containing compounds, cobalt containing compounds, copper containing compounds, or any mixture thereof.

[0055] Examples of cross-linking agents can include, but are not limited to, elemental sulfur, organo-sulfur compounds, peroxides, or any mixture thereof. The elemental sulfur can be in the form of prills or pellets, can be molten, or a combination thereof. Illustrative organo-sulfur compounds can include, but are not limited to, hydrocarbyl polysulfides, thiuram polysulfides, alkyl phenol disulfides, mercaptobenzylthiazol and derivatives thereof, dithiocarbamates, thiuram monosulfides, morpholine disulfides, N,N’ -disulphide of caprolactam, or any mixture thereof. Illustrative peroxides can include, but are not limited to, dihydrocarbyl peroxides, such as di-tert-butyl peroxide and dicumyl peroxide, or any mixture thereof.

[0056] Other additives include, for example, paraffins such as Fischer-Tropsch and petroleum slack (crude or raw) paraffins, fluxants, esters of fatty acids and functionalized wax, dialkyldiamides, acids such as phosphoric acid, superphosphoric acid, polyphosphoric acid, sulfuric acid, hydrochloric acid, and nitric acid, resin components, such as rosin acids, tall oil pitch, pine tar pitch, pine rosins, tall oil rosins, asphaltites, fluxants oils from vegetal or mineral sources and derivatives, polymers generally used in order to improve the mechanical performance of the asphalt, (i.e., commonly used in the modification of asphalt) such as butyl rubber, polybutadiene rubber, polyisoprene rubber, polyisobutene rubber, ethylene / vinyl acetate copolymer, polyacrylate, polymethacrylate, polychloroprene, polynorbomene, ethylene / propylene / diene (EPDM) terpolymer, a random or block copolymer of a vinyl aromatic compound, e.g., styrene, and a conjugated diene, or any mixture thereof. Additionally, or alternatively, other additives may include one or more bioresins, one or more acrylic polymers, one or more constituents having isocyanate-reactive functional groups, hydroxyl groups, amine groups, epoxy groups, phenol groups, or anhydride groups, such as additives described in U.S. Patent Nos. 10,808,140 or 11,059,749, the entirety of each of which are incorporated by reference herein. The amount of such auxiliary additives when present inthe asphalt binder composition may range from about 0.01 weight percent (wt%) to about 40 wt% based on the total weight of the asphalt binder composition.

[0057] These additives may already be part of the modified or unmodified binder or added later with the crack-resistant additive that forms the asphalt binder composition.

[0058] The manufacturing process of a binder involves blending the base asphalt cement with the necessary additives under controlled conditions to achieve the desired performance properties. The steps generally include: (1) Selection of Base Asphalt: Choosing an appropriate base asphalt that meets the initial performance criteria; (2) Modification: Adding polymers and other modifiers to the base asphalt to enhance its properties; (3) Mixing and Blending: Thoroughly mixing the components to ensure a homogeneous blend; and (4) Quality Control: Testing the modified binder to ensure it meets the specified performance grade.

[0059] An example asphalt binder composition may include about 85 wt% to about 95 wt% base bitumen, about 3 wt% to about 5 wt% polymer modifier (e.g., SBS), about 0.5 wt% to about 2 wt% anti-stripping agent (e.g., hydrated lime), about 1 wt% to about 5 wt% rejuvenator (if applicable, for recycled asphalt), and / or about 0.3 wt% to about 1 wt% warm mix additive (if applicable). The specific composition of an asphalt binder can vary widely based on the intended application, environmental conditions, and performance requirements. The base component is always bitumen, but various additives and modifiers are incorporated to tailor the binder’s properties to meet specific needs, such as improved flexibility, enhanced resistance to deformation, better adhesion, or lower production temperatures.

[0060] In some examples, the binder is a PG 64S-22 binder, which is designed to perform well in climates with moderate temperatures. A PG 64S-22 binder should pass various tests to ensure it can withstand high pavement temperatures (up to 64°C) and low temperatures (down to -22°C) without significant performance degradation. The PG 64S-22 binder may have a profile of withstanding high temperatures from 64 degrees Celsius to below 70 degrees Celsius and withstanding low temperatures from -22 degrees Celsius to above -28 degrees Celsius without significant performance degradation.

[0061] Two binders of the same performance grade (e.g., PG 64-S22) may have very different properties. For example, one PG 64S-22 binder may withstand a maximum temperature of 69 degrees Celsius and a minimum temperature of -27 degrees Celsius, and another PG 64S-22 may withstand a maximum temperature of 64 degrees Celsius and a minimum temperature of -22 degrees Celsius. Same performance-graded binders may have different viscosities, cracking properties (ATc), rut resistances, flexibility, lower production temperatures, durability, and other performance properties.

[0062] In the described asphalt compositions, at least one additive or at least one modifier is added to a selected binder to improve the performance properties of the binder or asphalt composition. When added to a binder, the additive reduces the minimum temperature at which cracking begins for the binder. Additionally, or alternatively, the binder maintains a ATc greater than about -2°C at the reduced temperature. The additive may also reduce the maximum temperature at which rutting begins for the binder. The additive may also improve the Glover- Rowe value and the R-value of the binder.

[0063] The additive may be an organic compound, such as an alkyl aromatic hydrocarbon, alkylarene, petroleum derivative, hydrocarbon derivative, alkylbenzene derivative, reaction product of an alkylation process, alkyl hydrocarbon derivative, linear or branched alkyl hydrocarbon derivative, straight-chain hydrocarbon derivatives, functionalized hydrocarbon derivative, functionalized aliphatic hydrocarbon, functionalized aromatic hydrocarbon, alkylated and functionalized benzene-based compound, alkylated and functionalized benzene- based surfactant or polymer, alkyl-substituted benzene compound, non-polyoxyethylene alkyl and aromatic hydrocarbon derivative, or functionalized alkyl and benzene-based surfactant or polymer. The additive may be a mixture of isomers of at least one compound selected from the list.

[0064] Alkyl-substituted monoaromatic or unfused polyaromatic compound are organic compounds containing alkyl groups attached to either single aromatic rings (monoaromatic) or multiple separate aromatic rings that are not fused together (unfused poly aromatic). Unfused polyaromatic compounds can exhibit a combination of properties associated with both monoaromatic and polyaromatic structures. Alkyl-substituted indicates the presence of alkyl groups attached to the aromatic rings. Alkyl groups are chains of carbon and hydrogen atoms derived from alkanes. Monoaromatic refers to compounds containing a single aromatic ring per molecule. These compounds have one benzene ring or a similar aromatic system. Unfused polyaromatic refers to compounds with multiple aromatic rings that are not fused together. Unfused polyaromatic compounds have separate, independent aromatic rings within the molecule.

[0065] Alkyl-substituted benzene compounds may include compounds where a single benzene ring is functionalized with alkyl groups.

[0066] Linear generally refers to a molecular structure where atoms or groups are arranged in a straight line. Linear implies a continuous sequence of atoms without branches or side chains. Straight-chain refers to a molecule with a main chain of carbon atoms arranged in a straightline, without any branching or cycles; it is a subset of linear molecules, where the atoms are arranged in a single continuous chain.

[0067] Linear hydrocarbon derivatives are derived from straight-chain hydrocarbons, which consist of a linear arrangement of carbon atoms. These derivatives maintain the linear structure of their parent hydrocarbons even after chemical modifications, such as the addition of functional groups or substituents. Straight-chain hydrocarbon derivatives may be derived from straight-chain hydrocarbons and specifically emphasizes the linear nature of the parent hydrocarbon structure.

[0068] Hydrocarbon derivatives may be derived from hydrocarbons and involve modifications or combinations of hydrocarbon chains. Functionalized hydrocarbon derivatives may include compounds derived from hydrocarbons that have been chemically modified by the addition of functional groups (such as alkyl, ethoxyl, or polymer branches) to enhance their properties and applications. Functionalized aliphatic and aromatic hydrocarbons may include compounds derived from simple aliphatic (straight or branched chain) and aromatic (single benzene ring) hydrocarbons that have been chemically modified with various functional groups to enhance their properties and applications.

[0069] Alkylated and functionalized benzene-based compounds may include compounds derived from benzene in which alkyl groups have been introduced through alkylation processes and further functionalized to modify their properties and applications. Functionalized alkyl and benzene-based compounds may include compounds derived from alkyl and benzene -based hydrocarbons that have been chemically modified (functionalized) to enhance their properties and applications.

[0070] Non-polyoxyethylene alkyl and aromatic hydrocarbon derivatives may include compounds derived from alkyl and aromatic hydrocarbons that do not involve polyoxyethylene (ethoxylation) modifications or complex fatty acid structures.

[0071] A reaction product of an alkylation process may include an alkylate or alkyl aromatic hydrocarbon, such as an alkylarene. The alkylation process may be performed through various methods, such as Friedel-Crafts alkylation and petroleum refining alkylation. Alkylarene includes alkylbenzenes, such as linear alkylbenzenes.

[0072] In some examples, the additive may include an alkylate or a mixture that includes an alkylate. An alkylate may be a mixture of high-octane, branched-chain hydrocarbons produced by the alkylation process. The hydrocarbons in an alkylate may be branched to some degree, for example, highly branched. An alkylate may be primarily composed of aliphatic hydrocarbons with some (e.g., minimal) aromatic content. An alkylate may be usedto produce a linear alkylbenzene. Examples of an alkylate include alkylate 300 and alkylate H-250, both of which are high-octane blending components that are used in gasoline created through an alkylation process. This process of producing alkylate 300 may involve reacting isobutane with light olefins like propylene, butylene, or pentylene in the presence of an acid catalyst, usually sulfuric acid or hydrofluoric acid. The process of producing alkylate H-250 may vary from that of alkylate 300. Both alkylate 300 and alkylate H-250 may be a mixture of branched-chain alkanes, which can be used to enhance the octane rating and combustion properties of gasoline, making it cleaner and more efficient. However, they may have differences in their chemical composition, production processes, and performance characteristics.

[0073] In some examples, the additive may include a compound (e.g., aromatic hydrocarbon compound) with a hydrocarbon group and an aromatic group or a mixture thereof. The hydrocarbon group may various groups derived from hydrocarbons, such as an alkyl group (e.g., methyl, ethyl), alkenyl group (e.g., vinyl, allyl), alkynyl group (e.g., ethynyl, propargyl), cycloalyl group (e.g., cyclpropyl, cyclohexyl), cycloalkenyl group (e.g., cyclohexenyl). The compound may have one or more hydrocarbon groups and one or more aromatic groups, and a plurality of aromatic groups may be fused or disconnected with each other. The additive may be an alkyl aromatic compound or a mixture that includes alkyl aromatic compounds (i.e., a compound with an alkyl group attached to an aromatic compound). The additive may be a mixture of different isomers (e.g., structural isomer, stereoisomer, conformational isomer, functional isomer, etc.) of the alkyl aromatic compounds. The alkyl group may include a methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, tert-butyl group, or other longer alkyl chains. An aromatic compound may be any molecule that contains at least one aromatic ring, such as arenes (e.g., benzene, toluene, naphthalene, anthracene, etc.), heteroaromatic compounds (e.g., pyridine, furan, thiophene, indole, etc.), and polycyclic aromatic compounds (e.g., phenanthrene, pyrene, etc.). The aromatic ring may be benzene, naphthalene, anthracene, phenanthrene, or heteroaromatic (e.g., aromatic ring containing heteroatoms like nitrogen, oxygen, or sulfur). For example, an alkyl group may be attached to a benzene group as such may be the case in an alkylarene, which includes alkylbenzene (e.g., linear alkylbenzene). The alkyl group may be linear or branched and have different chain lengths from C8 to C30, C12 to C24, C12 to C14, C14 to C16, C16 to C20, or C20 to C24. The additive may be a mixture of compounds having an aromatic group and alkyl groups of average chain lengths in the ranges of C8 to C30, C12 to C24, C12 to C14, C14 to C16, C16 to C20, or C20 to C24.Different substituents or functional groups (e.g., heteroatom, halide, or the like) may be attached to the aromatic ring at different positions. Examples of alkylarenes include alkylated aromatics (e.g., alkylbenzene), which are aromatic compounds with alkyl substituents attached to the aromatic ring, and polycyclic hydrocarbons (PAHs) with alkyl substituents, which are aromatic compounds with multiple fused aromatic rings and alkyl substituents attached. Examples of alkylbenzenes include ethylbenzene, propylbenzene, and isopropylbenzene. Examples of linear alkylbezenes (LABs) include linear alkylbenzene sulfonate and dodecylbenzene. Further examples of LABs include alkylate 225, which is a mixture of linear alkylbenzenes with chain lengths ranging from C10 to C14 as a product of an alkylation reaction involving benzene and linear olefins.

[0074] Alkylated aromatic compound includes molecules where one or more alkyl groups are attached to an aromatic ring that has been through an aklyation process. This may include alkylates, alkylbenzenes, etc. Alkylated benzene derivatives may refer to compounds that are derived from benzene through alkylation, where an alkyl group is added to the benzene ring. These derivatives retain the basic aromatic structure of benzene but have been chemically modified by the addition of one or more alkyl groups.

[0075] In some examples, the additive may be the additive CAS # 156105-29-2 that was registered in June 1994, or an additive derived from CAS # 156105-29-2 that was registered in June 1994 (i.e. CAS # 156105-29-2 that was registered in June 1994 was used as a material or reactant to make the additive). The additive or reactant may have a molecular weight of 395. The additive or reactant may be characterized as (C6H5)(C18-26) benzene+alkyl group (straight chained and branched mixtures). The C18-26 may be predominantly C20-24 with trace amounts (ppm) of C14 to C19 and C25 to C30. The alkyl group may be connected to the benzene ring on the first carbon on the alkyl group (the “first position”) in trace amounts, on the second carbon on the alkyl group (the “second position”) in an amount of about 11- 12% of the mixture, and on the third, fourth, fifth carbon, etc. on the alkyl group in an amount of about 88-89% of the mixture. The Iodine number, which is a measure of the degree of unsaturation of the alkyl chain, may be below 0.9. The additive or reactant may be made through a one-step Friedel-Crafts reaction that is done in a constant stirred tank reactor (CSTR). Benzene (liq) is added to the alkylene (liq) in the presence of HF catalyst. This process is done at around 170°F and 70 psig (851bs absolute). In this process, less unreacted benzene is in the product compared to other processes and products, which is significant since the EPA has strict limits on the amount of benzene in a product before it is deemed hazardous.

[0076] In some examples, the additive may be a comb polymer. The comb polymer may include a) x mole fractions of constitutional unit Cl having the formula (I)b) y mole fractions of constitutional unit C2 having the formula (II)and c) z mole fractions of constitutional unit C3 having the formula (III)where Ri is a Cio - C24 straight or branched chain alkyl group,R2 is a C4 - C24 straight or branched chain alkyl group,a is an integer from 0 to about 20, x is a number from about 0.1 to about 0.4, y is a number from about 0.2 to about 0.5 and z is a number from about 0.3 to about 0.6 with the proviso that x + y + z = 1.

[0077] In some examples, Ri is a C12 to C22 straight or branched chain alkyl group. In some examples, Ri is a C14 to C20 straight or branched chain alkyl group. In some examples, Ri is a C16 to C18 straight or branched chain alkyl group.

[0078] In some examples, R2 is a C6 to C22 straight or branched chain alkyl group. In some examples, R2 is a C8 to C20 straight or branched chain alkyl group. In some examples, R2 is a CIO to C18 straight or branched chain alkyl group. In some examples, R2 is a C12 to C16 straight or branched chain alkyl group. In some examples, R2 may include a alkyl phenyl or a nonylphenol derivative.

[0079] In some examples, a is an integer from about 2 to about 18, or from about 4 to about 16, or from about 6 to about 14 or from about 2 to about 12. In some examples, a is less than about 18 or less than about 16, or less than about 14, or less than about 12, or less than about 10 or less than about 8.

[0080] In some examples, x is a number from about 0.12 to about 0.35. In some examples, x is a number from about 0.15 to about 0.3. In some examples, x is a number from about 0.17 to about 0.25. In some examples, x is a number from about 0.18 to about 0.22.

[0081] In some examples, y is a number from about 0.24 to about 0.44. In some examples, y is a number from about 0.27 to about 0.4. In some examples, y is a number from about 0.3 to about 0.38. In some examples, y is a number from about 0.33 to about 0.37.

[0082] In some examples, z is a number from about 0.33 to about 0.55. In some examples, z is a number from about 0.36 to about 0.5. In some examples, z is a number from about 0.4 to about 0.48. In some examples, z is a number from about 0.44 to about 0.46.

[0083] The sequence of the constitutional units Cl, C2, and C3 can be alternating, in block sequence or random. In some embodiments, the weight average molecular weight of the comb polymer may be from about 2,000-20,000 grams per mole (g / mol), or from about 4,000-15,000 g / mol or from about 8,000-12,000 g / mol. The weight average molecular weight may be determined by known methods, for example, gel permeation chromatography, using polystyrene as a calibration standard and tetrahydrofuran as eluent.

[0084] The comb polymers of the present disclosure may be made by reacting maleic anhydride, an imidazoline having the formula (IV)where Ri is defined above, and an amine having the formula (V)where R2 and a are defined above in the presence of an initiator. Examples of initiators includes, but are not limited to, azo initiators well known in the technical field, such as AIBN and 1,1-azo-biscyclohexanecarbonitrile, and also peroxy compounds such as methyl ethyl ketone peroxide, acetylacetone peroxide, dilauryl peroxide, tert-butyl per-2-ethyl-hexanoate, ketone peroxide, tert-butyl peroctoate, methyl isobutyl ketone peroxide, cyclohexanone peroxide, dibenzoyl peroxide, tert-butyl peroxybenzoate, tert-butyl peroxyisopropylcarbonate, 2,5-bis(2-ethylhexanoylperoxy)-2,5-dimethylhexane, tert-butyl peroxy-2-ethylhexanoate, tertbutyl peroxy-3,5,5-trimethylhexanoate, dicumyl peroxide, l,l-bis-(tert- butylperoxy)cyclohexane, 1 , 1 -bis(tert-butyl-peroxy)-3 ,3 ,5-trimethylcyclohexane, cumyl hydro-peroxide, tert-butyl hydroperoxide, bis(4-tert-butyl-cyclohexyl)peroxydicarbonate, mixtures of two or more of the aforementioned compounds with one another, and also mixtures of the aforementioned compounds with compounds which have not been mentioned and can likewise form free radicals. The reaction may be carried out at standard pressure, reduced pressure or elevated pressure. The reaction temperature may generally be in the range of about 20°C-200°C, or about 50°C-150°C or about 80°C-130°C.

[0085] The reaction may also be carried out with or without a solvent. Examples of solvents include, but are not limited to, benzene and derivatives thereof such as xylene, toluene, ethylbenzene and other linear alkyl benzenes; organic esters such as ethyl acetate and isopropyl acetate; ketones such as methyl ethyl ketone and methyl isobutyl ketone; and cyclic ethers such as tetrahydrofuran and 1,3-dioxane.

[0086] In some examples, the comb polymer may be produced using linear alkyl benzene.The comb polymer may be produced according to the following reaction:Linear Aikyi Benzene

[0087] where Ri, R2 and a are defined above, R3 and R4 are C10-C24 straight or branched chain alkyl groups and m, n and o are each independently integers up to about 2,000.

[0088] In some examples, the comb polymer may have characteristics of being a polymeric dispersant of asphaltene that is effective in lowering the viscosity of heavy crudes and preventing asphaltene deposition. Examples of comb polymers include 172-88 SURFONIC® OFA 830 HF and 172-90 SURFONIC® OFA 830 HF, available from Indorama Ventures Oxides, The Woodlands, Texas. Both 172-88 and 172-90, included a tallow amine (e.g., R2 = Cl 8 and a =0). Additionally, among other reactants, 172-88 included Jeffamine B100, available from Indorama Ventures Oxides, (R2 = nonylphenol and a = 13.5).

[0089] In some examples, the additive may have a flash point of at least 300°F. The additive may have to be stored in tanks at temperatures of at least 300°F.

[0090] A synergistic combination refers to the combination of multiple components that work together in a way that produces a greater effect than the sum of their individual effects, for example, enhanced performance, efficiency, or functionality beyond what could be achieved by individual components alone. Careful consideration of the balance of each component ensures the composition meets the standards for performance at lower temperatures. The synergy arising from the combined action of a binder and an additive result in improved or superior characteristics of crack-resistance at lower temperatures while maintaining or improving the properties of the composition (e.g., lower viscosity, lower shear strain, lowerstiffness, higher flexibility, or combinations thereof) as compared to a composition without the additive.

[0091] As an example, if the cracking property ATc is greater than -2°C when the binderadditive composition is at a certain low temperature, the binder- additive may be considered to have a synergistic combination of components, or a higher degree of synergy compared to other binder-additive compositions that cannot go below the certain low temperature without lowering ATc at or below -2°C. Additionally, or alternatively, if the Glover-Rowe values of the binder-additive composition do not reach the onset or full cracking line, the binder- additive composition may be considered to have a synergistic combination of components, or a higher degree of synergy compared to other binder- additive compositions that do reach the onset or full cracking line. A first binder-additive composition may be considered to have greater synergy than a second binder-additive composition if Glover-Rowe values suggests that the first binder-additive composition is further away from reaching the onset or full cracking line than the second binder- additive composition. Different binder- additive compositions may be characterized by different wt%. A binder- additive composition with little or no increase in R- value may be considered to have a synergy or greater degree of synergy of its components than a binder-additive composition with more increase in R- value. The combination of components may be considered to have an even greater degree of synergy if the composition has other desired characteristics, such as reducing viscosity.

[0092] The degree of synergy could be affected by the type and amounts of each component in the composition. The asphalt composition may have between greater than 0 to 20 wt% of additives with the remainder being the binder (e.g., 80 wt% to less than 100 wt%). The additive may be 0.25 wt% to 15 wt% of the asphalt composition or any number in between the range. For example, the additive may be 0.25 wt%, 0.5 wt%, 1 wt%, 2 wt%, 3 wt%, 4 wt%, 5 wt%, 6 wt%, 7 wt%, 8 wt%, 9 wt%, 10 wt%, 11 wt%, 12 wt%, 13 wt%, 14 wt%, or 15 wt% of the asphalt composition. The additive may be a single additive or a combination of additives. The additive may be a mixture of different components. For example, the additive may be an alkylate, alkylarene (e.g., linear alkylbenzene), or a comb polymer, or combinations thereof. The amount of the additive may determine the performance (e.g., low temperature performance) of the binder.

[0093] In some examples, the asphalt binder composition may include an asphalt and an asphalt additive that may include a comb polymer. In some examples, the amount of the asphalt additive comprising the comb polymer present in the asphalt binder composition is at least about 0.25 wt%, or at least about 0.5 wt%, or at least about 1 wt%, or at least about 1.5 wt% orat least about 2 wt% by weight, or at least about 2.5 wt% based on the total weight of the asphalt. In some examples, the amount of asphalt additive comprising the comb polymer present in the asphalt binder composition is at most about 10 wt%, or at most about 8 wt% or at most about 6 wt% or at most about 4 wt% based on the total weight of asphalt. In some examples, the asphalt binder composition comprises from about 0.5 wt% to about 10% by weight of asphalt additive based on the weight of the total weight of asphalt; in some examples from about 1.0 wt% to about 5 wt% by of asphalt additive based on the total weight of the asphalt; and in some examples from about 2 wt% to about 4 wt% by weight of asphalt additive based on the total weight of the asphalt.

[0094] The asphalt composition can be made, produced, formed, or otherwise prepared by mixing, blending, or otherwise combining the binder (e.g., unmodified base asphalt or modified asphalt) and the asphalt additive (e.g., alkylate, alkylbenzene, comb polymer, etc.). For example, the asphalt, the asphalt additive, and if present, any additional auxiliary additives, can be blended with one another by a tank blending process and / or an in-line blending process. In tank blending, the components can be added to a tank in desired or predetermined proportions and mixed using various combinations of pumping / recirculation systems and / or agitators (e.g., vertical shaft with paddles, side-mounted, ribbon blender, etc.). In in-line blending, each component can be pumped into a single pipe, conduit, or other line. Meters and / or other flow control devices can be used to control the input flow of each individual component by weight, e.g., a mass flow meters, and / or by volume. The components can be blended or mixed using only the natural shear resulting from fluid flow through the line. One or more static and / or mechanical in-line mixers can also be used to improve or promote the blending or mixing of the components within the line. One or more in-line measuring devices such as viscometers and / or densitometers can be used to measure or monitor one or more properties of the asphalt binder composition that can improve the consistency of the asphalt binder composition over time. The asphalt binder composition, whether prepared by tank blending, in-line blending, or any other method, can be transferred, for example, via a pump, to a transport vessel such as a tanker truck, a rail car, or a barge.

[0095] In some examples, the asphalt binder composition may be combined with aggregate to form an asphalt mixture. In some embodiments, the asphalt mixture can include at least about 80 wt% or at least about 85 wt%, or at least about 88 wt%, or at least about 90 wt%, or at least about 92 wt%, or at least about 94 wt%, or at least about 96 wt%, or at least about 97 wt%, or at least about 98 wt%, or at least about 99 wt% of aggregate, based on the total weight of the asphalt mixture. For example, the asphalt mixture can include from about 85 wt. % to about99 wt%, or from about 90 wt% to about 97 wt. %, or from about 93 wt% to about 97 wt % of aggregate, based on the total weight of the asphalt mixture.

[0096] In another embodiment, the asphalt mixture may include less than about 15 wt%, or less than about 10 wt%, or less than about 8 wt%, or less than about 6 wt%, or less than about 5 wt%, or less than about 4 wt%, or less than about 3 wt%, or less than about 2 wt% or less than about 1 wt% of the asphalt binder composition based on the total weight of the asphalt mixture. For example, the asphalt mixture can include from about 1 wt% to about 15 wt%, or from about 3 wt% to about 12 wt%, or from about 5 wt% to about 10 wt% of the asphalt binder composition, based on the total weight of the asphalt mixture.

[0097] In some examples, the asphalt mixture may further include other common components of asphalt mixtures, for example fillers such as organic fibers (for example: cellulose, cotton, polypropylene, polyester, polyvinyl alcohol and polyamide fibers) and / or inorganic fibers (for example: glass, metal or carbon fibers).

[0098] The asphalt binder composition and the preparation process described in this disclosure can be applied to any asphalt mixture production methods such as those employing asphalt emulsion addition, asphalt foam addition, anhydrous asphalt addition, or any of the several processes for hot, warm or semi-warm mixture production (where production temperature is above room temperature but below that in regular hot mixing process.

[0099] In one particular embodiment, there is provided a method for the production of asphalt pavements that includes mixing the asphalt binder composition as described above with aggregate and optionally fillers at temperatures between about 150°C-190°C, in case of mastic asphalt up to 250°C, to obtain an asphalt mixture; filling the asphalt mixture in a truck or storage silo; transporting it to a building site; applying the asphalt mixture to a surface with a paver to obtain an asphalt surface; and compacting the asphalt surface with a roller.

[0100] In some examples, there is provided a method for the production of asphalt pavements that includes transporting the asphalt binder composition as described above to the building site; spraying the asphalt binder composition on a surface; distributing aggregates over a layer of the sprayed asphalt binder composition; and pressing the aggregates into the layer of the asphalt binder composition using a roller.

[0101] While most of the discussion has centered on paving applications, asphalt binder compositions incorporating the present asphalt additive also have utility in emulsions and in non-paving applications. Some examples of non-paving applications are in protective coatings for metal articles, binders for construction boards, waterproofing compositions, asphaltsealcoats for parking lots and driveways, binders for fuel pellets and briquettes, and in roofing materials (e.g., roofing shingles).

[0102] Additionally, or alternatively, the described asphalt binder compositions may facilitate recycling of asphalt containing materials, such as, for example, reclaimed asphalt pavement (RAP), reclaimed asphalt-based shingles, or the like. As an example, the asphalt binder compositions described herein may maintain or improve the performance characteristics of high RAP mixes, for example, improving the viscosity of the high RAP mix or lower the temperature grade (e.g., PG Low) of the high RAP mix. “High RAP Mix” or “High Reclaimed Asphalt Pavement Mix” refers to asphalt mixtures that contain a higher percentage of reclaimed asphalt pavement (RAP) compared to conventional mixtures. RAP can be obtained by milling and removing old asphalt pavement from roads, then processing it to be reused in new asphalt mixtures. High RAP mixtures typically contain a higher percentage of RAP, often up to 50% or more, compared to traditional mixtures, which usually contain lower percentages of RAP. Using a higher percentage of RAP in asphalt mixtures offers several benefits. For example, incorporating RAP reduces the need for virgin aggregates and asphalt binder, resulting in cost savings for road construction projects. Also, recycling RAP reduces the demand for new raw materials and decreases the amount of asphalt pavement waste sent to landfills, making road construction more sustainable. Furthermore, by reusing existing materials, high RAP mixtures help conserve natural resources like aggregates and asphalt binder. However, using a higher percentage of RAP in asphalt mixtures also presents challenges, such as maintaining desired performance characteristics and addressing variability in RAP quality. Proper mix design and quality control measures are essential to ensure that high RAP mixtures meet the required performance standards for durability, rut resistance, and fatigue resistance. Overall, high RAP mixtures offer a promising solution for sustainable road construction and pavement rehabilitation, provided that proper design, construction, and quality control practices are implemented.

[0103] EXPERIMENTAL STUDIES.

[0104] Additives (e.g., 9825-8-1 A300, 172-88 Surfonic OFA 830 HF, 172-90 Surfonic OFA 830 HF, Alkylate 225, Alkylate H-250, and 9825-8-1 4800) were tested to see if they could lower the low-temperature grade of a binder, improve the viscosity of high RAP mixes , or both. A300 is an alkylate. Alkylate H-250 is an alkylate. 172-88 Surfonic OFA 830 HF and 172-90 Surfonic OFA 830 HF are comb polymers, as described above. Alkylate 225 is a linear alkylbenzene (LAB). 9825-8-1 4800 is an alkylate.

[0105] Preliminary study: With the addition of 2.5wt% additive to a binder, there was at least a half-grade reduction in both the high- temperature and low-temperature grades. Approximately 3 wt% additives (e.g., additives studied in Examples 1-4) in a binder composition could produce at least about a full grade reduction in the low-temperature grade of the binder composition. The addition of additives could improve the cracking property ATc. The addition of any of the listed additives may be an easy and cost-effective way to adjust the binder to lower its temperature grades.

[0106] To evaluate the extent of binder grade reduction achieved with an additive, the studies were based on adding 0 wt%, 3 wt%, 6 wt%, and / or 9 wt% of the additive to the binder to determine the extent of grade reduction by using the additive and any possible plateauing of effects from the additive.

[0107] The various binder blends were tested with the full M 320 continuous grading, which was used to evaluate the scale of grade reduction that can be achieved with the additive. Also, any positive or negative effect on the overall binder properties were evaluated. The binder blends may also be subjected to a Rolling Thin Film Oven Test (RTFOT) and / or Pressure Aging Vessel (PAV) test.

[0108] AASHTO M 320 is a specification developed by the American Association of State Highway and Transportation Officials (AASHTO) that outlines the testing procedures and criteria for determining the performance grades (PG) of asphalt binders. AASHTO M 320 provides the standardized testing methods and criteria for determining the rheological properties of asphalt binders, and the PG system uses this information to classify binders based on their performance characteristics at high and low temperatures.

[0109] The continuous grading aspect of M 320 refers to the method used to determine the rheological properties of asphalt binders over a range of temperatures, rather than discrete temperature points, which is essential for predicting their performance in different climatic and loading conditions. This method allows for a more comprehensive assessment of the binder’s performance characteristics, including its stiffness and flexibility across different temperature conditions. Continuous grading provides a more accurate representation of how asphalt binders behave under real-world conditions, enabling engineers to select binders that are suitable for specific climates, traffic loads, and pavement applications.

[0110] In addition to continuous grading, the rolling thin film oven test (RTFOT) and / or the pressure aging vessel (PAV) test may be used to evaluate the properties of asphalt binder, but they serve different purposes and simulate different aging conditions. The RTFOT test simulates short-term aging, while the PAV test simulates long-term aging.

[0111] The RTFOT test is standardized test method used in the asphalt industry to simulate the short-term aging of asphalt binder that occurs during the mixing and laying process of asphalt pavement. During the RTFOT test, a thin film of asphalt binder is placed in a rotating, stainless steel container and exposed to elevated temperatures (usually around 163 °C or 325 °F) for a specified duration (typically 85 to 90 minutes). The rotation of the container ensures uniform heating of the asphalt binder, simulating the mixing and compacting process that occurs during asphalt pavement construction. The purpose of the RTFOT test is to evaluate the susceptibility of asphalt binder to oxidative aging, hardening, and stiffening when exposed to high temperatures and oxygen. These aging effects can impact the performance of asphalt pavement, leading to issues such as cracking, rutting, and fatigue. By subjecting the asphalt binder to controlled heating and aging conditions in the RTFOT test, engineers and researchers can assess its resistance to short-term aging and predict its performance in actual pavement applications. The results of the RTFOT test help in the selection and specification of asphalt binders that will provide durable and long-lasting pavement surfaces.

[0112] The PAV test is a laboratory procedure used to simulate long-term oxidative aging of asphalt binder, which occurs over the lifespan of asphalt pavement. During the PAV test, asphalt binder samples are subjected to elevated temperatures (typically around 100°C or 212°F) and an optionally oxygen rich gas at elevated pressure (e.g., 2.1 MPA or 300 psi) in a sealed vessel for an extended period (usually 20 hours). This accelerated aging process allows researchers to assess how the binder’s properties change over time when exposed to oxidative aging conditions. 1 PAV may refer to a single cycle or duration of aging that the sample has undergone within the PAV. Overall, the PAV test provides valuable insights into the aging behavior of asphalt binders, helping to inform pavement design, material selection, and performance prediction in road construction and maintenance projects.

[0113] The PAV test is commonly used in conjunction with the RTFOT to evaluate the shortterm and long-term aging characteristics of asphalt binders. By combining these two tests, engineers and researchers can gain a comprehensive understanding of the binder’ s performance and durability under various environmental conditions.

[0114] The evaluation was performed by analyzing properties, such as ATc properties, Glover Rowe aging effects, and binder R values, which are properties that have been identified as being related to binder durability. As many softening additives degrade durability, any additive that is neutral to or improves properties was considered interesting.

[0115] In the context of asphalt binder performance, ATc (Delta Tc) is an important parameter used to evaluate the low-temperature performance and cracking susceptibility of asphalt binders.

[0116] ATc is defined as the difference between two critical temperatures: Tc,BBR (Bending Beam Rheometer) which is the critical temperature determined from the BBR test, measuring the binder’s stiffness and ability to resist cracking at low temperatures; and Tc,DSR (Dynamic Shear Rheometer) which is the critical temperature determined from the DSR test, which measures the binder’s ability to resist fatigue cracking.

[0117] The importance of ATc is reflected in the following physical properties. Cracking Susceptibility: A more negative ATc value may indicate a higher susceptibility to cracking. Binders with a ATc value less than -5 °C are generally considered to be at higher risk for low- temperature cracking. Performance Indicator: ATc serves as an additional performance indicator, complementing traditional specifications like PG grading. It helps in identifying aged binders that might fail prematurely due to excessive stiffness or lack of relaxation properties.

[0118] ATc is calculated using the formula: ATc=TcDSR-TcBBR, where: Tc,DSR (Critical Temperature from Dynamic Shear Rheometer): This temperature is determined from the DSR test, which measures the binder’s ability to resist fatigue cracking and maintain its integrity under cyclic loading at intermediate temperatures. Tc,BBR (Critical Temperature from Bending Beam Rheometer): This temperature is determined from the BBR test, which measures the stiffness (S) and relaxation properties (m- value) of the binder at low temperatures to assess its ability to resist thermal cracking.

[0119] The technique to determine ATc include performing the BBR test according to standard methods (e.g., AASHTO T313) to determine the temperatures at which the stiffness (S) equals 300 MPa and the m-value equals 0.3, which are typically denoted as Tc,S and Tc,m respectively. Tc,BBR is the higher (less negative) of these two temperatures: TcBBR=max(TcS ,Tcm). The technique also includes performing the DSR test according to standard methods (e.g., AASHTO T315) to determine the critical temperature Tc,DSR, which is the temperature at which the binder meets the fatigue cracking criteria. The technique also includes calculating ATc by subtracting Tc,BBR from Tc,DSR: ATc=TcDSR-TcBBR.

[0120] When interpreting ATc values, ATc > -2°C generally indicates good low-temperature performance and low susceptibility to cracking; ATc between -2°C and -5°C indicates moderate risk of low-temperature cracking, i.e., the binder may still perform well but could be more susceptible to cracking in harsher conditions or over longer periods; and ATc < -5°Cindicates a high risk of low-temperature cracking, i.e., such binders are typically considered less suitable for cold climates or regions where low-temperature performance is critical.

[0121] Practical Use of ATc includes the following considerations. Quality Control: Asphalt producers and pavement engineers use ATc to assess the quality and durability of asphalt binders, especially those subjected to long-term aging. Material Selection: Selecting binders with a favorable ATc value helps in ensuring better performance of pavements in cold regions. Performance Specification: Agencies may include ATc as part of performance-based specifications to ensure the long-term performance of asphalt pavements. By incorporating ATc into the evaluation of asphalt binders, engineers and material scientists can better predict and mitigate potential issues related to low-temperature cracking, thus enhancing the durability and lifespan of asphalt pavements.

[0122] The Glover-Rowe parameter, determined using the Dynamic Shear Rheometer (DSR), is a factor for evaluating the aging and performance of asphalt binders, particularly in terms of their susceptibility to cracking. This parameter combines aspects of both modulus and phase angle to assess the brittleness of the binder. It has become an important measure in assessing the durability of asphalt pavements, especially for predicting fatigue and thermal cracking.

[0123] Components of the Glover-Rowe Parameter include the complex modulus (|G*|) which represents the total resistance of the binder to deformation under load, phase angle (8) which indicates the lag between the applied stress and the resulting strain (a low phase angle suggests a more elastic material, while a high phase angle indicates a more viscous material). The Glover- Ro we parameter is calculated using the following formula: G-R Parameter I G* I / sin(8)

[0124] To determine the Glover-Rowe Parameter, DSR testing is conducted on the asphalt binder. This test measures the complex shear modulus (|G*|) and phase angle (8) of the binder at various temperatures and frequencies. Generally, the DSR test results are used to calculate |G*| / sin(8) at the specified frequency and temperature. Typically, the Glover-Rowe parameter is evaluated at a frequency of 0.005 rad / s (very low frequency) and at a temperature of 15 °C. This simulates the long-term loading and low-temperature conditions that are critical for assessing the aging and brittleness of the binder.

[0125] When interpreting Glover-Rowe parameter values: G-R < 180 kPa indicates good performance with low susceptibility to cracking, i.e., such binders are typically more elastic and can accommodate stresses without significant cracking; G-R between 180 kPa and 450 kPa indicates moderate risk of cracking, i.e., these binders may perform adequately under normal conditions but might be more prone to cracking under severe stress or aging; and G-R> 450 kPa indicates high risk of cracking, i.e., these binders are generally considered brittle and are likely to crack under stress, especially after long-term aging.

[0126] The Glover-Rowe parameter value is useful in evaluating the following factors. Aging Assessment: The Glover-Rowe parameter is particularly useful for evaluating the long-term aging characteristics of asphalt binders because aging can significantly increase the modulus and decrease the phase angle, leading to higher G-R values. Performance Prediction: By using the Glover- Rowe parameter, engineers can better predict the performance of asphalt pavements and take measures to select appropriate binders that will resist cracking and enhance the pavement’s lifespan. Material Selection: Including the Glover-Rowe parameter in material specifications helps ensure the selection of binders that maintain their integrity and flexibility over time, particularly in regions with extreme temperatures.

[0127] Overall, the Glover-Rowe parameter, derived from DSR testing, is a valuable tool for evaluating the durability and performance of asphalt binders. By assessing the binder’s susceptibility to cracking, especially after aging, it helps engineers make informed decisions to enhance pavement longevity and performance.

[0128] The R-value, in the context of asphalt engineering, specifically asphalt pavement design, refers to the resistance to permanent deformation, i.e., a measure of the resistance of an asphalt mixture to permanent deformation (rutting) under traffic loads. Rutting, or permanent deformation, occurs when asphalt pavement deforms under repeated traffic loads, leading to depressions and uneven surfaces. Hence, the R-value quantifies the ability of the asphalt pavement to maintain its shape and structural integrity over time.

[0129] The R-value is typically determined through laboratory testing using a Dynamic Shear Rheometer (DSR) or a similar testing device. The DSR test subjects the asphalt mixture to repeated shear loading at different temperatures and frequencies to simulate field conditions. The complex shear modulus (G*) of the asphalt binder is measured at various temperatures, usually ranging from high to low temperatures relevant to the climate conditions where the pavement will be used.

[0130] The R-value is calculated as the ratio of the complex shear modulus at a high temperature (e.g., 64 °C or 70 °C) to the complex shear modulus at a low temperature (e.g., 4 °C or 7°C). A higher R-value indicates greater resistance to rutting.

[0131] The R-value is useful in evaluating the following factors. Pavement Performance: The R-value is a crucial parameter in pavement design as it directly influences the resistance of the asphalt pavement to rutting and deformation under traffic loads. Durability: Pavements with higher R-values are more durable and can withstand heavy traffic and adverse weatherconditions without experiencing excessive rutting. Longevity: By selecting asphalt mixtures with appropriate R-values, engineers can design pavements that have longer service lives and require fewer maintenance interventions.

[0132] Factors Affecting R-value include, but are not limited to, the properties of the asphalt binder used in the mixture, including viscosity, stiffness, and temperature susceptibility, affect the R-value; the size and distribution of aggregate particles in the asphalt mixture influence its compatibility and resistance to permanent deformation; and factors such as asphalt content, air void content, and filler type can impact the R-value of the asphalt mixture.

[0133] Engineers use the R-value extensively in pavement design and analysis to select asphalt mixtures that meet the required performance specifications for rut resistance. It helps optimize the design of asphalt pavements to ensure longevity, safety, and cost-effectiveness over their service lives. In asphalt engineering, the R-value is a fundamental parameter used to assess the rutting resistance of asphalt mixtures. By evaluating the R-value during pavement design, engineers can select asphalt materials and mix designs that provide durable and long-lasting pavements capable of withstanding the rigors of traffic and environmental conditions.

[0134] The rheological index, often denoted as the “m-value,” is a parameter used in asphalt engineering to characterize the temperature sensitivity of an asphalt binder’s viscosity. It quantifies the rate of change of the viscosity of the binder with temperature, providing insights into its behavior during mixing, compaction, and service life. The rheological index is determined through laboratory testing, typically using a rotational viscometer or similar rheological testing equipment. The test involves measuring the viscosity of the asphalt binder at different temperatures, covering a range relevant to the climate conditions where the pavement will be used. The viscosity-temperature relationship of the asphalt binder is then fitted to an empirical model, such as the Arrhenius equation or the Power Law model. The rheological index, "m," is calculated as the slope of the logarithm of viscosity plotted against temperature.

[0135] The m-value is useful in evaluating the following factors. Temperature Sensitivity: The rheological index provides crucial information about how the viscosity of the asphalt binder changes with temperature, which helps engineers understand how the binder will behave under different environmental conditions, including during construction and in-service. Mixing and Compaction: Asphalt mixtures must be workable during mixing and compaction to ensure proper placement and density; the rheological index helps determine the optimal mixing and compaction temperatures for asphalt pavements. Performance Prediction: By quantifying the temperature sensitivity of the binder, the rheological index aids in predicting the performanceof the asphalt pavement over its service life, including its resistance to rutting, fatigue cracking, and thermal cracking.

[0136] Factors Affecting m- value include, but are not limited to, the composition of the asphalt binder, including its viscosity grade, rheological modifiers (such as polymers or additives), and source materials, influences its rheological properties and rheological index; and the temperature range over which the rheological index is measured affects its value (different temperature ranges may be relevant depending on the climate conditions where the pavement will be used).

[0137] Engineers use the rheological index in asphalt binder selection, mix design, and pavement analysis to ensure that the asphalt mixture meets performance requirements under varying temperature conditions. It helps optimize the design of asphalt pavements for specific climates, traffic loads, and environmental conditions by selecting binders with appropriate temperature sensitivity. The rheological index, or "m-value," is an important parameter in asphalt engineering that characterizes the temperature sensitivity of asphalt binders. By quantifying how viscosity changes with temperature, the rheological index provides valuable insights into the behavior and performance of asphalt pavements over their service lives, aiding in pavement design, construction, and maintenance decisions.

[0138] EXAMPLE 1.

[0139] The extent of binder grade reduction achieved with additive 9825-8-1 A300 (A300) was explored. Two base binders classified as PG 64S-22 having different cracking properties ATc of -0.4 and -6.7 were used. The base binder having ATc of -0.4 was considered to have moderate durability properties and is denoted G. The base binder having ATc of -6.7 was considered to have poor properties and is denoted B. The additive 9825-8-1 A300 was blended with each of the two base binders at different weight percentages of 0 wt%, 3 wt%, 6 wt%, and 9 wt%. Samples of binder- additive blends were identified as G 0, G 3, G 6, G 9, B 0, B 3, B 6, and B 9. G represents the binder with ATc of -0.4, B represents the binder with ATc of -6.7, and the number 0, 3, 6, and 9 represent the weight percent of additive in the blend. As shown in the testing plan of Table 1, the binder blends were subjected to continuous grading, RTFOT, and PAV. Full PG continuous grade, ATc, R value, and Glover Rowe properties were determined for the blends and compared to the base binder, and the results are shown in Table 2.Table 1. Testing Plan for Binder- Additive Blends EvaluationTable 2: Binder Blends Test Results.

[0140] FIG. 1 shows the continuous grading of binder- A300 additive blends. FIG. 2 shows the high-temperature performance grade and reduction for binder- A300 additive blends. Referring to Table 2 and as shown in FIGS. 1 and 2, the addition of the additive A300 had a very similar effect on the high-temperature performance grades of both binders G (ATc = -0.4) and B (ATc = -6.7). As shown in FIGS. 1 and 2, with each 3 wt% increase of A300 relative to the binder, the high-temperature grade decreased by about one grade or about 6°C. For example, 3 wt%, 6 wt%, and 9 wt% A300 would reduce the high-temperature grade by about one grade from PG 64 to a PG 58, PG 58 to PG 52, and PG 52 to PG 46, respectively. For the binder B (ATc= -6.7), the high temperature reduction was slightly less than for the binder G (ATc = -0.4), but it was uniform up to the 9 wt% A300.

[0141] FIG. 3 shows the low-temperature performance grade and reduction for binder-A300 additive blends. Referring to Table 2 and as shown in FIGS. 1 and 3, the effect on the low temperature properties of the different binders with different ATc by the addition of the A300 show some differences. At up to 6 wt% A300, the reductions in low temperature grade were similar for both the binder G (ATc = -0.4) and binder B (ATc = -6.7) with the reduction slightly higher for binder G (ATc = -0.4). The change from 6 wt% to 9 wt% of A300 for the binder G (ATc = -0.4) maintained the consistent trend of lowering the low-temperature grade at about 3.5°C. The 9 wt% A300 in the binder B (ATc = -6.7) provided no additional low temperature grade reduction. The addition of a soft oil (e.g., A300) in the binder B (ATc = -6.7) that already has a higher amount of oil as compared to binder G (ATc = -0.4) may not be able to change the relaxation on the binder.

[0142] Additionally, ATc cracking properties were analyzed to evaluate the fatigue and durability of the binders. In the context of asphalt binder performance, ATc (Delta Tc) is an important parameter used to evaluate the low-temperature performance and cracking susceptibility of asphalt binders. This is a value determined from the bending beam rheometer S and m measurements at two temperatures. The specific temperature where the BBR specification limits on stiffness S meets 300MPa and the m value meets 0.3 are determined. These temperatures are almost never the same. This is where the delta A comes from. The T critical temperature for m is subtracted from the Tcriticai temperature for S and ATc is determined. STc -26.2 minus mTc -25.9 is a -0.3 ATc. The larger and more negative the difference the more prone the pavement is to age cracking.

[0143] FIG. 4 shows ATc values of binder-A300 additive blends. Referring to Table 2 and FIG. 4, ATc of Binder G (ATc = -0.4) was not negatively affected by 0 wt%, 3 wt%, 6 wt%, and 9 wt% of A300; ATc stayed nearly constant from 0 wt% to 9 wt% A300. More importantly, the addition of the A300 had minimal negative effect on the ATc of the binder B (ATc = -6.7). Compared to no addition of A300, the addition of 3 wt% A300 to the binder B (ATc = -6.7) only changed the ATc by -0.4, and the addition of 6 wt% A300 to the binder B (ATc = -6.7) changed ATc by -2.1. From a binder blend with Binder B (ATc = -6.7) and 6 wt% A300 to a binder blend with Binder B (ATc = -6.7) and 9 wt% A300, there was no change in low- temperature grade and a change in ATc from -4.4 to -11.1. This suggests that a binder composition with Binder B (ATc = -6.7) and more than 6 wt% A300 may negatively affect the chemistry of the binder by, for example, increasing its brittleness.

[0144] Moreover, Glover Rowe properties were evaluated. The Glover Rowe (GR) value is an estimation of ductility developed by Charles Glover of Texas A&M. The ductility work was based on the idea that when the ductility of the asphalt is 5 cm at 15 °C there is the onset of cracking in the pavement. Rowe later provided a simplified equation for the ductility estimate using Dynamic Shear Rheometer (DSR) data, and the new parameter was called the Glover- Rowe, G*x (cos8)2 / sin8. These properties are measured at 15°C and a frequency of 0.005 radians / second in the DSR. A value of 180 kPa relates to the 5 cm ductility and was considered the onset of cracking, and the value of 600 kPa is considered full pavement cracking and relates to the ductility of 3 cm. The Glover-Rowe is also being evaluated as a cracking indicator by several researchers. The Glover-Rowe can also be determined for different aging conditions.

[0145] FIG. 5 shows the Gio ver- Rowe parameters of Modulus G* and Phase Angle for binder- A300 additive blends. Referring to Table 2 and FIG. 5, each of the binders G (ATc = -0.4) and B (ATc = -6.7) exhibited improvement in GR values with the addition of A300. With additions of A300 in increasing weight percent relative to the binder, GR values were consistently reduced, and the modulus G* decreased and the phase angle increased accordingly. As shown in FIG. 5, the PAV and RTFOT results for each sample binder- A300 additive blend were linked. For each sample of specific binder and specific weight percent of A300, the PAV parameter is located to the left of and higher than the RTFOT parameter (i.e., the RTFOT parameter is located to the right of and lower than the PAV parameter). None of the PAV or RTFOT values of Binder G (ATc = -0.4) samples reached the onset cracking line, not even with 20-hour PAV aging. As weight percent of A300 is increased in the binder composition with Binder G (ATc = -0.4), the PAV and RTFOT values shifted down and to the right, indicating that there was no increase in brittleness as the weight percent of A300 is increased. As weight percent of A300 is increased in the binder composition with the Binder B (ATc = -6.7), the RTFOT values shifted down and to the right; the PAV values shifted down, which indicates softening, but did not shift to the right to the same extent as observed with RTFOT values. Generally, for either binder mixed with 3 wt% A300, PAV and RTFOT values are shifted down and to the right; at 6 wt% A300, both binder compositions exhibited some increase in aging but less than the increase in aging at 9 wt% A300. The Grover-Rowe is consistent with what was observed with the low-temperature grade reduction and ATc values, where the A300 improves the properties of Binder B with less ideal ATc but not as significantly as it does for Binder G with more ideal ATc.

[0146] Rheological index (R value) is another property used to evaluate aging of the binder. The R value is determined from the log of the glassy modulus of the binder minus the log ofthe modulus where the phase angle is 45°. The glassy modulus is the modulus where the phase angle is basically 0° or almost completely elastic at low temperature. The larger the R value the more brittle and prone to cracking the aged binder is likely to be. This property typically requires more testing of the binder at multiple temperatures and frequencies to determine.

[0147] FIG. 6 shows the R-value for binder-A300 additive blends. Referring to Table 2 and as shown in FIG. 6, A300 minimally increased the R- values for binder G and binder B, but the increase in the R-value for binder B was greater than the R-value for binder G.

[0148] In summary for Example 1: The additive A300 was added to two PG 64S-22 base binders — binder G with ATc = -0.4 binder B with ATc = -6.7. ATc = -0.4 is considered better than ATc = -6.7. The A300 was added to each binder at 3 wt%, 6 wt%, and 9 wt%. For both binders, the high-temperature grade was reduced almost one full grade for every 3 wt% increase of A300 in the binder- A300 composition from 0 wt% to 9 wt% of A300. For binder G-A300 composition, the low-temperature grade was reduced almost one full grade for every 3 wt% increase of A300 from 0 wt% to 9 wt% of A300. For binder B-A300 composition, the low- temperature grade was reduced almost one full grade for every 3 wt% increase of A300 from 0 wt% to 6 wt% of A300. The 9 wt% of A300 provided no additional low-temperature grade reduction of the binder B-A300 composition. For the binder G-A300 composition, every 3 wt% increase of A300 did not reduce ATc, which remained constant over the full range of 0 wt% to 9 wt% of A300. For the binder B-A300 composition, 3 wt% of A300 barely reduced ATc, 6 wt% of A300 had a minor negative effect of causing ATc to be a more negative number from -6.7 to -8.8 by 2.1 units, and 9 wt% of A300 had a more significant negative effect of causing ATc to be an even more negative number from -6.7 to - 11.1 by 4.4 units. For the binder B-A300 composition, the low-temperature grade and ATc results are consistent with each other. For binder G-A300 composition, the Glover-Rowe value improved for every 3 wt% increase of A300 from 0 wt% to 9 wt% of A300. For binder B-A300 composition, the Glover Rowe value improved with 3 wt% and 6 wt% of A300 but only minimally improved with 9 wt% A300 in the PAV sample. For both binders, A300 had little effect on the R-value, indicating little to no negative effect on aging.

[0149] Overall, up to 9 wt% of A300 in a composition with binder G lowered the high- temperature grade and low-temperature of the composition. Up to 6 wt% of A300 in a composition with binder B lowered the low-temperature grade of the composition. A300 exhibited no negative effects on the cracking properties of the binder G. Only very minimal effect on the cracking properties of binder G mixed with up to 6 wt% of A300. Therefore,A300 reduces the PG High and PG low of a binder and is an effective recycling agent for RAP mixes.

[0150] EXAMPLE 2.

[0151] The extent of binder grade reduction achieved with additives 9825-8-1 A300 (A300), 172-88 Surfonic OFA 830 HF (172-88), and 172-90 Surfonic OFA 830 HF (172-90) were explored. For each sample, 3 wt% of the additives were added to a PG 64S-22 base binder “B6919” with a specific performance profile of PG 65.5-25.4.

[0152] FIG. 7 shows the continuous grading for different binder- additive blends. For the binder- A300 composition, 3 wt% A300 changed the grade of the composition to PG 60.0-30.8, which was a 5.5-degree reduction on the high-temperature grade and a 5.5-degree reduction on the low-temperature grade. For the binder-172-88 composition, 3 wt% 172-88 changed the grade of the composition to PG 62.4-29.0, which was a 3.1 -degree reduction on the high- temperature grade and a 3.6-degree reduction on the low-temperature grade. For the binder- 172-90 composition, 3 wt% 172-90 changed the grade of the composition to PG 63.0-28.6, which was a 2.5-degree reduction on the high temperature grade and a 3.2-degree reduction on the low-temperature grade. The 3% wt of A300 had the largest effect on the base binder followed by 3 wt% of 172-88 and 3 wt% of 172-90. It was noted that the A300 is the base material for the other two additives. All additives changed the PG low one grade lower, however, the 9825-8-1 A300 lowered the PG low almost two grades.

[0153] FIG. 8 shows the PG intermediate G* sinS and phase angle for each additive in the base binder at 3 wt%. The 3% wt of 9825-8-1 A300 met the PG 58-28 intermediate grade requirement of G*sin8 less than 5000MPa at 19C°. Both 172-88 and 172-90 at 3 wt% met the PG 58-28 intermediate temperature requirement, but only with the secondary criteria that if 8 was greater than 42°, then 6000MPa is allowable for G*sin8. There is no phase angle requirement if the value is less than 5000MPa.

[0154] FIG. 9 shows the ATc for the base binder and the three additive blends. The base binder had a very good ATc with a value of -0.15. The 3% wt of 9825-8-1 A300 had the greatest effect on ATc by reducing it to -0.81. Both the 172-88 and 172-90 additives had very minor effect with ATc values of -0.19 and -0.52. Values of -3 to -5 are considered poor for 1 PAV aged binder so even the -0.85 would be considered good.

[0155] FIG. 10 shows the rotational viscosity values at 135C for the binder-3 wt% additive blend. The rotational viscosity at 135C0was evaluated to determine any reductions related to the additives. The 3% wt of 9825-8-1 A300 had the greatest effect on viscosity with a 0.1 Pa-sreduction. Both the 172-88 and 172-90 additives had very minor effect on viscosity with about a 0.05 reduction, which is half of the 9825-8-1 A300.

[0156] In summary for Example 2: Three additives were evaluated as binder modifiers: 9825- 8-1 A300, 172-88 Surfonic OFA 830 HF, and 172-90 Surfonic OFA 830 HF. Each additive was blended at 3 wt% relative to a PG 64-22 binder, and the continuous PG was determined to evaluate the effect of the additives on the base binder. The 9825-8-1 A300 had the greatest effect on the base binder. There was a 5 °C reduction on both the high and low PG continuous grade and a significant reduction in the intermediate PG grade. The ATc value reduced by - 0.66 to -0.81, which is still considered a good value. The viscosity also had the greater reduction of 0.1. Both the 172-88 and 172-90 additives had very similar effect on the base binder at the 3% wt. This was typically half of the reduction compared to that of the 9825-8-1 A300.

[0157] Overall, this evaluation suggested that the additives can effectively be used to reduce the PG grade of the binder with minimal negative effects on durability property ATc. This is based on testing with a good durability base binder.

[0158] EXAMPEE 3.

[0159] Two additives Alkylate 225 (225) and Alkylate H-250 (250) at a 6% wt. in a composition with PG 64S-22 base binder was evaluated. The various binder blends were tested with the full M 320 continuous grading. At the 6% wt, both additives failed the M 320 testing as the mass loss in the RTFOT was greater than 1% for both.

[0160] FIG. 11 shows the continuous grading, RTFOT, and PAV results of the 225 additive. The 225 additive at 6 wt% had a mass loss of 5.37% indicating that almost all of the material (i.e., 225 additive) evaporated in the RTFOT, and the remaining binder after the RTFOT procedure matched the base properties.

[0161] FIG. 12 shows the continuous grading, RTFOT, and PAV results of the 250 additive. The 250 additive at 6 wt% had a mass loss of 1.64% and provided a one grade reduction; however, with a mass loss greater than 1%, the 250 additive fails the specification.

[0162] EXAMPLE 4.

[0163] The extent of binder grade reduction achieved with the new additive 9825-8-1 4800 was evaluated. Two base binders classified as PG 64S-22 having different cracking properties ATc of -0.4 and -6.7 were used. The base binder having ATc of -0.4 was considered to have moderate durability properties and is denoted G. The base binder having ATc of -6.7 was considered to have poor properties and is denoted B. The additive 9825-8-1 4800 was blended with each of the two base binders at different weight percentages of 0 wt%, 3 wt%, 6 wt%, and9 wt%. Samples of binder- additive blends were identified as G 0, G 3, G 6, G 9, B 0, B 3, B 6, and B 9. G represents the binder with ATc of -0.4, B represents the binder with ATc of -6.7, and the number 0, 3, 6, and 9 represent the wt% of additive in the blend. As shown in the testing plan of Table 3, the binder blends were subjected to continuous grading, RTFOT, and PAV. Full PG continuous grade, ATc, R value, and Glover Rowe properties were determined for the blends and compared to the base binder, and the results are shown in Table 4.31Table 3. Testing Plan for Binder- Additive Blends EvaluationTable 4: Binder Blends Test Results.

[0164] FIG. 13 shows the continuous grading of binder- A300 additive blends. FIG. 14 shows the high-temperature performance grade and reduction for binder-4800 Additive blends. Referring to Table 4 and as shown in FIGS. 13 and 14, the addition of the additive 4800 had a very similar effect on the high-temperature performance grades of both binders G (ATc = -0.4) and B (ATc = -6.7). As shown in FIGS. 13 and 14, with each 3 wt% increase of 4800 relative to the binder, the high-temperature grade decreased by about one grade or about 6 degrees Celsius. For example, 3 wt%, 6 wt%, and 9 wt% 4800 would reduce the high-temperature grade about one grade from PG 64 to a PG 58, PG 58 to PG 52, and PG 52 to PG 46, respectively.For the binder B (ATc = -6.7), the high temperature reduction was slightly less than for the binder G (ATc = -0.4), but it was uniform up to the 9 wt% 4800.

[0165] FIG. 15 shows the low-temperature performance grade and reduction for Binder-4800 additive blends. Referring to Table 4 and as shown in FIGS. 13 and 15, the effect on the low temperature properties of the different binders with different ATc by the addition of the 4800 show some differences. At up to 6 wt% 4800, the reductions in low temperature grade were similar for both the binder G (ATc = -0.4) and binder B (ATc = -6.7) with the reduction slightly higher for binder G (ATc = -0.4). The change from 6 wt% to 9 wt% of 4800 for the binder G (ATc = -0.4) maintained the consistent trend of lowering the low-temperature grade at about 3.5°C. The 9 wt% 4800 in the binder B (ATc = -6.7) provided no additional low temperature grade reduction. The addition of a soft oil (e.g., 4800) in the binder B (ATc = -6.7) that already has a higher amount of oil as compared to binder G (ATc = -0.4) may not be able to change the relaxation on the binder.

[0166] FIG. 16 shows ATc values of binder-4800 additive blends. Referring to Table 4 and FIG. 16, ATc of Binder G (ATc = -0.4) was not negatively affected by 0 wt%, 3 wt%, 6 wt%, and 9 wt% of 4800; ATc stayed basically constant from 0 wt% to 9 wt% 4800. More importantly, the addition of the 4800 had minimal negative effect on the ATc of the binder B (ATc = -6.7). Compared to no addition of 4800, the addition of 3 wt% 4800 to the binder B (ATc = -6.7) only changed the ATc by -0.4, and the addition of 6 wt% 4800 to the binder B (ATc = -6.7) changed ATc by -2.1. From a binder blend with Binder B (ATc = -6.7) and 6 wt% 4800 to a binder blend with Binder B (ATc = -6.7) and 9 wt% 4800, there was no change in low-temperature grade and a change in ATc from -4.4 to -11.1. This suggests that a binder composition with Binder B (ATc = -6.7) h and more than 6 wt% 4800 may negatively affect the chemistry of the binder by, for example, increasing its brittleness.

[0167] Regarding Glover Rowe properties, FIG. 17 shows the Glover-Rowe parameters of Modulus G* and Phase Angle for binder-4800 additive blends. Referring to Table 4 and FIG. 17, each of the binders G (ATc = -0.4) and B (ATc = -6.7) exhibited improvement in GR values with the addition of 4800. With additions of 4800 in increasing weight percent relative to the binder, GR values were consistently reduced, and the modulus G* decreased and the phase angle increased accordingly. As shown in FIG. 17, the PAV and RTFOT results for each sample binder-4800 additive blend were linked. For each sample of specific binder and specific weight percent of 4800, the PAV parameter is located to the left of and higher than the RTFOT parameter (i.e., the RTFOT parameter is located to the right of and lower than the PAV parameter). None of the PAV or RTFOT values of Binder G (ATc = -0.4) samples reached theonset cracking line, not even with 20-hour PAV aging. As weight percent of 4800 is increased in the binder composition with Binder G (ATc = -0.4), the PAV and RTFOT values shifted down and to the right, indicating that there was no increase in brittleness as the weight percent of 4800 is increased. As weight percent of 4800 is increased in the binder composition with the Binder B (ATc = -6.7), the RTFOT values shifted down and to the right; the PAV values shifted down, which indicates softening, but did not shift to the right to the same extent as observed with RTFOT values. Generally, for either binder mixed with 3 wt% 4800, PAV and RTFOT values are shifted down and to the right; at 6 wt% 4800, both binder compositions exhibited some increase in aging but less than the increase in aging at 9 wt% 4800. The Grover- Rowe is consistent with what was observed with the low-temperature grade reduction and ATc values, where the 4800 improves the properties of Binder B with less ideal ATc but not as significantly as it does for Binder G with more ideal ATc.

[0168] FIG. 18 shows the R-value for binder-4800 additive blends. Referring to Table 4 and as shown in FIG. 18, 4800 minimally increased the R- values for binder G and binder B, but the increase in the R-value for binder B was greater than the R-value for binder G.

[0169] In summary for Example 4: The additive 4800 was added to two PG 64S-22 base binders — binder G with ATc = -0.4 binder B with ATc = -6.7. ATc = -0.4 is considered better than ATc = -6.7. The 4800 was added to each binder at 3 wt%, 6 wt%, and 9 wt%. For both binders, the high-temperature grade was reduced almost one full grade for every 3 wt% increase of 4800 in the binder-4800 composition from 0 wt% to 9 wt% of 4800. For binder G-4800 composition, the low-temperature grade was reduced almost one full grade for every 3 wt% increase of 4800 from 0 wt% to 9 wt% of 4800. For binder B-4800 composition, the low- temperature grade was reduced almost one full grade for every 3 wt% increase of 4800 from 0 wt% to 6 wt% of 4800. 9 wt% of 4800 provided no additional low-temperature grade reduction of the binder B-4800 composition. For the binder G-4800 composition, every 3 wt% increase of 4800 did not reduce ATc, which remained constant over the full range of 0 wt% to 9 wt% of 4800. For the binder B-4800 composition, 3 wt% of 4800 barely reduced ATc, 6 wt% of 4800 had a minor negative effect of causing ATc to be a more negative number from -6.7 to -8.8 by 2.1 units, and 9 wt% of 4800 had a more significant negative effect of causing ATc to be an even more negative number from -6.7 to - 11.1 by 4.4 units. For the binder B-4800 composition, the low-temperature grade and ATc results are consistent with each other. For binder G-4800 composition, the Glover-Rowe value improved for every 3 wt% increase of 4800 from 0 wt% to 9 wt% of 4800. For binder B-4800 composition, the Glover Rowe value improved with 3 wt% and 6 wt% of 4800 but only minimally improved with 9 wt% 4800 in the PAV sample.For both binders, 4800 had little effect on the R-value, indicating little to no negative effect on aging.

[0170] Overall, up to 9 wt% of 4800 in a composition with binder G lowered the high- temperature grade and low-temperature of the composition. Up to 6 wt% of 4800 in a composition with binder B lowered the low-temperature grade of the composition. 4800 exhibited no negative effects on the cracking properties of the binder G. Only very minimal effect on the cracking properties of binder G mixed with up to 6 wt% of 4800. Therefore, 4800 reduced the PG High and PG low of a binder and may be an effective recycling agent for RAP mixes.

[0171] While the disclosure has been described in connection with what is presently considered to be the most practical and preferred embodiments, it is to be understood that the disclosure is not to be limited to the disclosed embodiments, but on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims, which scope is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures as permitted under the law. Furthermore, it should be understood that while the use of the word preferable, preferably, or preferred in the description above indicates that feature so described may be more desirable, it nonetheless may not be necessary and any embodiment lacking the same may be contemplated as within the scope of the disclosure, that scope being defined by the claims that follow. In reading the claims it is intended that when words such as “a,” “an,” “at least one” and “at least a portion” are used, there is no intention to limit the claim to only one item unless specifically stated to the contrary in the claim. Further, when the language “at least a portion” and / or “a portion” is used the item may include a portion and / or the entire item unless specifically stated to the contrary.

Claims

CLAIMSWhat is claimed is:

1. A crack-resistant asphalt binder composition, comprising a synergistic combination of an asphalt binder and an additive, the additive having a flash point greater than 300 degrees Fahrenheit, the additive comprising a compound comprising an alkyl-substituted monoaromatic or unfused polyaromatic compound or a comb polymer, and the synergistic combination resulting in the crack-resistant asphalt composition being crack resistant at temperatures of less than -22°C.

2. The crack-resistant asphalt composition of claim 1, wherein crack-resistant asphalt composition has a Delta T Critical (ATc) that is greater than -2°C.

3. The crack-resistant asphalt composition of claim 1, wherein the additive comprises an alkyl-substituted monoaromatic or unfused polyaromatic compound.

4. The crack-resistant asphalt composition of claim 1, wherein the additive comprises a comb polymer.

5. The crack-resistant asphalt composition of claim 1, wherein the additive comprises an alkyl-substituted monoaromatic or unfused polyaromatic compound and a comb polymer.

6. The crack-resistant asphalt binder composition of claim 1 , wherein the alkyl- substituted monoaromatic or unfused polyaromatic compound is an alkylated aromatic compound.

7. The crack-resistant asphalt composition of claim 1, wherein the alkyl-substituted monoaromatic or unfused polyaromatic compound is selected from the group consisting of a linear alkylbenzene, an alkylate, and combinations thereof.

8. The crack-resistant asphalt composition of claim 1, wherein the alkyl-substituted monoaromatic or unfused polyaromatic compound comprises an alkylate.

9. The crack-resistant asphalt composition of claim 1, wherein the alkyl-substituted monoaromatic or unfused polyaromatic compound comprises an alkylarene.

10. The crack-resistant asphalt composition of claim 1, wherein the alkyl-substituted monoaromatic or unfused polyaromatic compound comprises a linear alkylbenzene.

11. The crack-resistant asphalt composition of claim 1, wherein the additive comprises a mixture of alkyl-substituted monoaromatic or unfused polyaromatic compounds, the compounds having alkyl groups with an average chain length of C20 to C24.

12. The crack-resistant asphalt composition of claim 1, where the alkyl-substituted monoaromatic or unfused polyaromatic compound comprises a single benzene ring.

13. The crack-resistant asphalt composition of claim 1, where the alkyl-substituted monoaromatic or unfused polyaromatic compound comprises a plurality of benzene rings, at least two of which are disconnected benzene rings.

14. The crack-resistant asphalt composition of claim 1, where the alkyl- substituted monoaromatic or unfused polyaromatic compound comprises a linear or branched alkyl group.

15. The crack-resistant asphalt composition of claim 1, wherein the asphalt binder without the additive is crack resistant at a temperature range between -16 degrees Celsius and above - 22 degrees Celsius, and wherein the synergistic combination results in the crack-resistant asphalt composition being crack resistant between below -22 degrees Celsius and above -28 degrees Celsius.

16. The crack-resistant asphalt composition of claim 1, wherein the asphalt binder without the additive is crack resistant at a temperature range between -22 degrees Celsius and -16 degrees Celsius, and the synergistic combination results in the crack-resistant asphalt composition being crack resistant between below -28 degrees Celsius and above -34 degrees Celsius.

17. The crack-resistant asphalt composition of claim 1, wherein the additive is within a range from about 3 weight percent (wt%) to about 9 wt% of the crack-resistant asphalt composition.

18. The crack-resistant asphalt composition of claim 1, wherein the asphalt binder comprises natural, modified base asphalt or reclaimed asphalt.

19. A method for preparing a crack-resistant asphalt binder composition, wherein the method comprises combining an asphalt binder with an additive comprising an alkylsubstituted monoaromatic or unfused polyaromatic compound or comb polymer to produce the crack-resistant asphalt binder composition being crack resistant at temperatures of less than -22 degrees Celsius.

20. A method for preserving a surface, wherein the method comprises: providing a crack-resistant asphalt binder composition comprising a synergistic combination of an asphalt binder and an additive comprising an alkyl-substituted monoaromatic or unfused polyaromatic compound, wherein the synergistic combination results in the crack-resistant asphalt composition being crack resistant at temperatures of less than -22 degrees Celsius; mixing the asphalt binder composition with aggregate material to produce an asphalt mixture; and placing the mixture onto the surface.

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