Bituminous materials with improved workability properties

Abstract

The invention relates to a bituminous material for bituminous mixes, comprising a hydrocarbon binder and at least one polymer additive of the following formula (1): R-[(OA)m]n-OH (1), the additive content in the binder being such that the hydroxyl value of the additive per kg of binder is between 200 and 700 g KOH / kg. The invention also relates to bituminous mixes based on a hydrocarbon binder as defined above, to aggregates and to a mineral filler. These bituminous mixes can be used for producing surfacing for roads, pavements or other urban infrastructure, and for producing sealing layers for structures and buildings.

Description

[0001] BITUMINOUS MATERIALS WITH IMPROVED HANDLING PROPERTIES

[0002] technical field

[0003] The present invention relates to a material for bituminous mixes comprising a hydrocarbon binder and at least one polymeric additive of a specific formula. The present invention also relates to a method for preparing the hydrocarbon binder-based material and its use in the preparation of hydrocarbon binder-based mixes. Finally, the present invention relates to the use of hydrocarbon binder-based mixes in road construction applications and more generally in the fields of construction and waterproofing.

[0004] Technical background

[0005] Bitumen is a viscoelastic product which, in order to be handled, requires heating, emulsification or additives through mixtures with fluxing agents of petroleum, petrochemical, carbochemical or even vegetable origin in order to reduce its viscosity.

[0006] In all cases, the expert will seek to restore the bitumen's properties while minimizing environmental constraints.

[0007] Among the targeted areas of application, we can mention asphaltic or bituminous products, as well as surface coatings, which can thus be manufactured and implemented at significantly lower temperatures than those required when said products contain a binder in which the additive according to the invention is absent.

[0008] The preparation of an asphaltic product (such as cast asphalt) or a bituminous product includes mixing the binder and fillers or aggregates at a temperature, called the manufacturing temperature, then spreading this mixture at a placement temperature, and then possible compaction.

[0009] In hot-mix techniques, the manufacturing temperature is generally above 160°C, while in intermediate, or warm-mix, techniques, this temperature is lowered by 10 to 40, or even 60°C. These techniques use anhydrous bitumen in a sufficiently fluid state to ensure good coating and achieve good final mechanical performance. The resulting mixture is transported for spreading, followed by possible compaction. The choice of process temperatures depends on the type of bitumen. For semi-coarse asphalt concrete and asphalt-bound gravel, for example, the temperatures of mixtures of aggregates and / or mineral fillers and bituminous binders, with pure bitumen having a penetration rating of 35 / 50, are generally 150 to 170°C, or even 160 to 180°C in harsher weather conditions. The spreading of such mixtures can be carried out at a temperature generally greater than or equal to 130°C.Compaction is generally carried out immediately after the mixture is spread so that the starting temperature of compaction is as close as possible to the temperature of the mixture when it was spread. Maintaining the bitumen in a sufficiently liquid, and therefore sufficiently warm, state ensures that the asphalt retains enough fluidity to perform these operations correctly.

[0010] However, these so-called hot techniques are not without their drawbacks:

[0011] Heating bituminous coatings leads to significant energy consumption, most often using fossil fuels, which are therefore non-renewable.

[0012] Concurrently, large quantities of greenhouse gases (GHGs) and partially collected volatile organic compounds are generated.

[0013] Working conditions are difficult due to thermal radiation, gaseous emissions, and odors.

[0014] When, due to uncontrollable factors such as deteriorating weather conditions, nightfall, or longer transport times, the temperature of the previously produced asphalt mix drops below a certain threshold, it can no longer be properly laid, leading to defects in compaction (void content) and mechanical performance. The robustness of the process is limited. To prevent this effect, it is common practice to produce the asphalt mix at higher temperatures, which exacerbates the first three defects mentioned.

[0015] Technical solutions are already proposed in the literature to reduce the four defects mentioned in the previous paragraph with regard to high-temperature coating techniques consisting of reducing the manufacturing temperature of the asphalt.

[0016] It is well known to those skilled in the art that adding additives to bituminous or asphaltic products during their preparation lowers the manufacturing temperature of the asphalt mix. Several examples can be cited in this regard.

[0017] The document FR2883882 describes bituminous products containing one or more additives, among which we can mention polyoxyalkylated additives and derivatives of alk(en)yl(aryl)sulfonic salts.

[0018] Document WO2007 / 141458 concerns bituminous products with added polymers, as well as aqueous emulsions of bituminous products, their mixtures with aggregates in the form of asphalt mixes, usable in the road sector as cold-poured asphalt mixes.

[0019] Document FR2923836 relates to a hot melt asphaltic or bituminous binder comprising at least one additive to lower the manufacturing temperature of the asphaltic product relative to that of the base product, said additive being chosen from fatty acid triglycerides.

[0020] Document WO2019 / 173458 concerns an asphaltic product dispersant comprising an alkylphenol copolymer with an alkyl chain between C1 and C4O-

[0021] Document FR2915485 describes a process for preparing and using mixtures of bituminous products with aggregates containing an additive A with chemical formula (RO-(CH2-CH(CH3)O) a- (CH2CH2O)b)cP(=O)-OHd to lower the application temperature of asphalt mixes.

[0022] Document WO2021160956 concerns the use of a polymeric additive at a concentration of between 0.01% and 10% by mass, relative to the total mass of the bituminous product, to delay the aging of bitumen. Document WO2022 / 159610 concerns an asphalt binder composition comprising at least one virgin asphalt binder (or air-blown virgin asphalt binder or a reclaimed material containing an asphalt binder), and an anti-aging agent resulting from a reaction between (i) a first material comprising a compound with one or more carbonyl groups and (ii) a second material reacting with the carbonyl group(s) of the first material and generating hydroxyl groups.

[0023] Technical problem to solve

[0024] However, it is necessary to develop increasingly efficient asphalt mix materials containing additives to lower the manufacturing and / or application temperature. The addition of this additive must not compromise the properties and performance of the final asphalt mixes. Indeed, the additive must be compatible with the other additives present in the mix, while also being non-toxic to humans and the environment, and free of any unpleasant odor. Furthermore, the workability of the asphalt or bituminous material at lower temperatures must be maintained, whether or not recycled materials are present. This research is part of the context of the carbon neutrality targets set by industries for 2050.

[0025] The inventors discovered that a material containing a particular polymeric additive of the polyether type at very low concentration makes it possible to reduce the temperature of manufacture and implementation (in particular spreading, compaction) of asphalts based on hydrocarbon binder while having excellent handling properties.

[0026] Brief description of the invention

[0027] The present invention relates to a material for bituminous coatings comprising a hydrocarbon binder and at least one polymeric additive of the following formula (1): R-[(OA)m]n-OH (1) in which:

[0028] - n represents the valence of the group R, n denotes an integer between 1 and 6,

[0029] - R represents a hydrogen atom, a linear or branched hydrocarbon chain, saturated or unsaturated, comprising from 1 to 50 carbon atoms, possibly bearing one or more hydroxyl groups, a hydrocarbon ring, monocyclic or polycyclic, aliphatic or aromatic, of 4 to 10 vertices, possibly comprising one or more heteroatoms chosen from oxygen, nitrogen and sulfur,

[0030] - OA represents an oxyalkylene chain chosen from oxyethylene (OE), oxypropylene (OP), oxybutylene (OB) and mixtures of two or more of them,

[0031] - m denotes an integer between 3 and 500, the content of additive in the binder being such that the hydroxyl number of the additive per kg of binder is between 200 and 700 g KOH / kg.

[0032] Other advantageous characteristics of the material according to the invention are specified below. -The polymeric additive of formula (1) of the material comprises 0 to 170 oxyethylene, preferably 0 to 90 oxyethylene and 0 to 170 oxybutylene, preferably 0 to 90 oxybutylene and 1 to 170 oxypropylene, preferably 3 to 90 oxypropylene.

[0033] -The polymeric additive in the material has a hydroxyl value between 200 and 500 mg KOH / g. -The polymeric additive in the material has a number-average molar mass between 200 and 10,000 g / mol 1 preferably between 200 and 8,000 g / mol 1 and preferably between 300 and 5,000 g.mol 1 .

[0034] -The R group of the formula (1) of the polymeric additive is chosen from a hydrogen atom, a methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, dodecyl group.

[0035] -When the polymeric additive of formula (1) comprises oxypropylene (OP) units, and oxyethylene (OE) and / or oxybutylene (OB) units, then the number of oxypropylene (OP) units is greater than the sum of the number of oxyethylene (OE) and / or oxybutylene (OB) units.

[0036] -The polymeric additive of formula (1) comprises oxyethylene (OE) and oxypropylene (OP) units, the oxypropylene units being predominant.

[0037] -The polymeric additive of formula (1) of the material is a diblock polymer.

[0038] -The additive within the material is an oxypropylene homopolymer.

[0039] -The hydrocarbon binder of the material is a bituminous binder, a synthetic binder or an oil.

[0040] According to one embodiment of the invention, the hydrocarbon binder of the material is a natural paraffinic or naphthenic bituminous binder.

[0041] According to another embodiment of the invention, the hydrocarbon binder of the material is an oil chosen from a vegetable oil or an animal fat.

[0042] -The material comprises from 0.02 to 5% by mass, relative to the mass of the hydrocarbon binder, of said polymeric additive, preferably from 0.05 to 1.5% by mass.

[0043] According to one embodiment of the invention, the material may further comprise at least one additional additive selected from:

[0044] - a wax of animal, vegetable or hydrocarbon origin,

[0045] - a natural resin, possibly modified, of plant origin, and

[0046] - adhesion enhancers, and more specifically phosphate esters.

[0047] The present invention also relates to the use of the material for the preparation of asphalt mixes.

[0048] The invention also relates to a hydrocarbon-based asphalt mix comprising a bituminous material as defined above and aggregates comprising recycled asphalt pavement (RAP). According to one embodiment of the invention, the binder of the additive within the asphalt mix is ​​a natural paraffinic or naphthenic bituminous binder. According to another embodiment of the invention, the asphalt mix comprises from 5% to 100% by mass of recycled asphalt pavement (RAP) aggregates, preferably from 10% to 70% by mass.

[0049] The invention also relates to a method for manufacturing a hydrocarbon binder-based asphalt comprising the following successive steps: a) mixing the material as defined above with aggregates at a temperature between 120°C and 180°C, b) spreading the hydrocarbon binder-based asphalt at a temperature equal to or lower than that of the mixture, preferably between 80°C and the temperature of the mixture.

[0050] The present invention also proposes a use of hydrocarbon binder-based asphalt for the manufacture of road surfaces, sidewalks or other urban developments, and waterproofing layers for structures and buildings.

[0051] Brief description of the figures

[0052] Figure 1 is a graph, relating to example 1, representing the measurement of the force required to de-cohesion the tested asphalt as a function of temperature.

[0053] Figure 2 is a graph, relating to example 2, representing the measurement of the force required to de-cohesion the tested asphalt as a function of temperature.

[0054] Figure 3 is a graph, relating to example 3, representing the measurement of the force required to de-cohesion the tested asphalt as a function of temperature.

[0055] Figure 4 is a graph, relating to example 4, representing the measurement of the force required to de-cohesion the tested asphalt as a function of temperature.

[0056] Detailed description of the invention

[0057] Other features, aspects, objects and advantages of the present invention will become even clearer upon reading the description that follows.

[0058] Unless otherwise stated, all percentages are mass percentages.

[0059] In this text, the quantities indicated for a given species may apply to that species according to all its definitions (as mentioned in this text), including more restricted definitions.

[0060] It is specified that the expressions "from ... to ..." and "between ... and ...." used in this description should be understood as including each of the mentioned limits.

[0061] Material

[0062] The present invention relates to a material comprising at least one polymeric additive as described above and a hydrocarbon binder. Polymeric additive

[0063] The polymeric additive has the following formula (1): R-[(OA)m]n-OH (1) in which:

[0064] - n represents the valence of the group R, n denotes an integer between 1 and 6,

[0065] - R represents a hydrogen atom, a linear or branched hydrocarbon chain, saturated or unsaturated, comprising from 1 to 50 carbon atoms, possibly bearing one or more hydroxyl groups, a hydrocarbon ring, monocyclic or polycyclic, aliphatic or aromatic, of 4 to 10 vertices, possibly comprising one or more heteroatoms chosen from oxygen, nitrogen and sulfur,

[0066] - OA represents an oxyalkylene unit chosen from oxyethylene (OE), oxypropylene (OP) and oxybutylene (OB) and mixtures of two or more of them,

[0067] -m represents the number of oxyalkylene units, m designates an integer between 3 and 500, the content of additive in the binder being such that the hydroxyl number of the additive per kg of binder is between 200 and 700 g KOH / kg.

[0068] The additive can be a block, alternating or statistical polymer.

[0069] Preferably, the additive of formula (1) comprises 0 to 170 oxyethylene (OE), preferably 0 to 90 oxyethylene (OE) and 0 to 170 oxybutylene (OB), preferably 0 to 90 oxybutylene (OB) and 1 to 170 oxypropylene (OP), preferably 3 to 90 oxypropylene (OP).

[0070] Preferably, the additive includes oxypropylene (OP) groups.

[0071] Preferably, when the polymeric additive of formula (1) comprises oxypropylene (OP) units, and oxyethylene (OE) and / or oxybutylene (OB) units, then the number of oxypropylene (OP) units is greater than the sum of the number of oxyethylene (OE) and / or oxybutylene (OB) units.

[0072] Advantageously, when the additive comprises oxyethylene (OE) and oxypropylene (OP) units, the oxypropylene (OP) units are predominant. Advantageously, the additive is then a diblock.

[0073] According to a preferred embodiment, the polymeric additive is a poly(oxypropylene) homopolymer (referred to as OP). Preferably, it is polypropylene glycol (PPG).

[0074] According to another embodiment, the polymeric additive is a block, statistical or alternating copolymer of oxyethylene and oxypropylene (denoted POE-POP), a block, statistical or alternating copolymer of oxypropylene and oxybutylene (POP-POB) and mixtures thereof.

[0075] In another embodiment, the polymeric additive is a block, random or alternating copolymer of oxyethylene, oxypropylene and oxybutylene (denoted OE-OP-OB).

[0076] In another embodiment, the polymeric additive is a block copolymer of oxyethylene, oxypropylene and oxybutylene (denoted OE-OP-OB), a block copolymer of oxypropylene, oxybutylene, oxypropylene (denoted OP-OB-OP), a block copolymer of oxybutylene, oxypropylene, oxybutylene (denoted OB-OP-OB), a block copolymer of oxypropylene, oxyethylene, oxypropylene (denoted OP-OE-OP), a block copolymer of oxybutylene, oxyethylene, oxybutylene (denoted OB-OE-OB), a block copolymer of oxyethylene, oxypropylene, oxyethylene (denoted OE-OP-OE), or mixtures thereof.

[0077] In another embodiment, the additive is a mixture of an oxypropylene homopolymer with at least one block, random or alternating copolymer as defined above.

[0078] Advantageously, the number of oxyalkylened units (OA) m is between 3 and 300, more particularly between 3 and 220.

[0079] The term n of the formula (I) of the polymeric additive according to the invention represents an integer between 1 and 6, preferably an integer between 1 and 4, more preferably an integer between 1 and 3, more particularly n is 1 or 2.

[0080] Preferably, the R group of the formula (1) of the polymeric additive is chosen from a hydrogen atom, a methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, dodecyl group.

[0081] In another embodiment, R represents the hydrocarbon skeleton of an initiator comprising 1 to 6 hydroxyl groups. Particularly suitable examples of initiators include glycerol, trimethylolpropane, pentaerythritol, oxyethylene, oxypropylene, and oxybutylene. For example, if the initiator is propanediol, polymerization of the (OA) units can occur at both ends, leading to a structure with the following formula: HO-(AO)a-CH2-CH2-CH2-(OA)b-OH. In this example, R is a propylene group, n = 2, m = a+b.

[0082] More specifically, R denotes a hydrogen atom. For example, the additive can have the following formula: H-(OCH(CH3)-CH2)m-OH in the case of poly(oxypropylene). In this example, R is a hydrogen atom, n = 1.

[0083] Preferably, the polymeric additive is a telechelic polyol, it includes an OH function at each end of the polymer chain.

[0084] Preferably, the polymeric additive has a number-average molar mass between 200 and 10,000 g / mol 1 , preferably between 200 and 8,000 g.mol 1 , and preferably between 300 and 5,000 g.mol 1 .

[0085] Hydroxyl number of the polymeric additive

[0086] Preferably, the polymeric additive has a hydroxyl value between 20 and 500 mg KOH / g.

[0087] The hydroxyl number represents the amount, expressed in milligrams, of potassium hydroxide required to neutralize the free hydroxyl groups contained in one gram of additive.

[0088] The hydroxyl number is calculated according to the following formula (2): with M(KOH) corresponding to the molar mass of potassium hydroxide equal to 56.1 g / mol, n represents the valence of the R group, n denotes an integer between 1 and 6, Mn corresponds to the number-average molar mass (in g / mol) of the polymeric additive.

[0089] Preferably, n is equal to 1 or 2.

[0090] When the additive is telechelic, n is equal to 2. When the additive includes only one OH function, n is equal to 1.

[0091] Next, this quantity of potassium hydroxide expressed in milligrams is reported to a quantity expressed in grams of potassium hydroxide per 1 kg of binder, taking into account the concentration of additive present in the binder.

[0092] The hydroxyl index per kg of binder is calculated according to the following formula (3):

[0093] With ioH(mg KoH / g additive) denotes the value calculated according to the previous formula (2) and C denotes the concentration of the additive in the binder expressed as a mass percentage.

[0094] Preferably, the additive content in the binder is such that the hydroxyl index per kg of binder is between 200 and 600 g KOH / kg of binder.

[0095] Hydrocarbon binder

[0096] A “binder” within the meaning of the present invention is a material whose thermoplastic properties allow it to harden upon cooling and to bind solid particles together.

[0097] The term "hydrocarbon binder" refers to any binder of fossil, vegetable, or synthetic origin that can be used to produce the material of the invention. Preferably, the hydrocarbon binder is a bituminous binder, a synthetic binder, or an oil.

[0098] The hydrocarbon binder can be a bitumen, and can be pure or modified, in particular by the addition of polymer(s), mineral fillers, for example pigments.

[0099] In the material as defined in the present invention, the quantity of hydrocarbon binder advantageously varies from 95 to 99.98% by mass relative to the total mass of the material, more advantageously from 98.5 to 99.95% by mass.

[0100] Preferably, the hydrocarbon binder comprises bitumen. The bituminous hydrocarbon binder according to the invention may be a bitumen of natural origin, those contained in deposits of natural bitumen, natural asphalt or oil sands.

[0101] The bituminous hydrocarbon binder according to the invention can be a bitumen obtained from crude oil refining. Bitumens are produced by atmospheric and / or vacuum distillation of petroleum. These bitumens may optionally be oxidized, blown, viscous-reduced, and / or deasphalted. The bitumens can be hard-grade or soft-grade. The different bitumens obtained by the refining processes can be combined to achieve the best technical compromise.

[0102] Preferably, the hydrocarbon binder is a natural paraffinic bituminous binder.

[0103] Preferably, the hydrocarbon binder is a natural naphthenic bituminous binder.

[0104] The binder can be a soft to hard binder, advantageously of a grade ranging from 160 / 220 to 10 / 20 corresponding to the penetration classes determined according to standards NF EN 12591 (2009-12-01) and NF EN 13924 (2016-03-17).

[0105] The hydrocarbon binder containing bitumen can be modified by adding polymers, which can be chosen from natural or synthetic polymers. These include, for example, polymers from the elastomer family, both synthetic and natural, and are indicative but not limited to:

[0106] - of statistical, multi-sequenced or star-shaped copolymers of styrene and butadiene or isoprene in all proportions (in particular styrene-butadiene-styrene (SBS), styrene-butadiene (SB, SBR for styrene-butadiene rubber), styrene-isoprene-styrene (SIS) block copolymers) or copolymers of the same chemical family (isoprene, natural rubber, ...), possibly cross-linked in-situ,

[0107] - of vinyl acetate and ethylene copolymers in all proportions,

[0108] - copolymers of ethylene and esters of acrylic, methacrylic acid or maleic anhydride, copolymers and terpolymers of ethylene and glycidyl methacrylate and polyolefins.

[0109] Synthetic binders, also called clear, pigmentable, or colorable binders, can also be used. These binders contain little or no asphaltenes and can therefore be colored. These synthetic binders are made from a mixture of a plasticizer, a structuring agent, and possibly one or more polymers. The plasticizer and structuring agent can be petroleum-based or vegetable-based. These mixtures are exemplified in several patents, notably patent EP 1481023 and patent application WO 2017 / 076814.

[0110] In another embodiment, the hydrocarbon binder is an oil, preferably an oil selected from a vegetable oil or an animal fat. These oils may be based on animal and / or vegetable fats (oils and greases). This oil may be a vegetable oil, a distillation residue of a vegetable oil, one of its derivatives such as its fatty acid portion, a mixture of fatty acids, a transesterification product (by a Ci-Cg alkanol) such as a methyl ester of the vegetable oil, or an alkyd resin derivative of the vegetable oil. Vegetable oil is defined as crude or refined oils obtained by crushing the seeds, kernels, or fruits of plants, particularly oilseeds, such as, but not limited to, rapeseed, sunflower, soybean, palm, castor, and corn oils, their derivatives, and mixtures thereof.

[0111] These three families of binder defined above can be used alone or in mixtures.

[0112] The material preferably comprises from 0.02% to 5% by mass relative to the mass of the hydrocarbon binder, of said polymeric additive. Preferably, the bituminous material comprises from 0.05% to 1.5% by mass, and preferably from 0.075% to 0.5% by mass relative to the mass of the hydrocarbon binder, of said polymeric additive.

[0113] Possible additives

[0114] The binder may include additives commonly used in the road construction field, such as polymers other than those covered by the invention.

[0115] Preferably, the adjuvant is chosen from

[0116] - a wax of animal, vegetable or hydrocarbon origin,

[0117] - a natural resin, possibly modified, of plant origin,

[0118] - adhesion enhancers and more specifically phosphate esters as described in document FR2915485.

[0119] We can also mention waxes of animal, vegetable or hydrocarbon origin, in particular long chain hydrocarbon waxes (more than 30 carbon atoms).

[0120] As an additional additive, a natural resin, possibly modified, of plant origin can also be introduced.

[0121] Plant-derived resin may contain abietic acid or its derivatives, including dehydroabietic acid, neoabietic acid, palustric acid, pimaric acid, levopimaric acid, isopimaric acid.

[0122] Other additives, such as adhesion enhancers, can be considered. Adhesion enhancers are defined as products exhibiting interfacial activity and added to the material to improve the coating quality of the granular material by the product and / or to improve the product's adhesion to the granular material and / or to improve the mechanical performance of the mixture between the product and the granular material. Non-limiting examples of adhesion enhancers include alkylamidopolyamines, alkylimidazolines and alkylimidazopolyamines, reaction products between polyamines and fatty carboxylic acids, as well as fatty-chain alkylpolyamines, and reaction products between fatty carboxylic acids or vegetable oil and diethanolamine, followed by a reaction with polyamines.Polyamines may include, but are not limited to, dimethylaminopropylamine, N-aminoethylpiperazine, diethylenetriamine, triethylenetetramine, and tetraethylenepentamine.

[0123] Material preparation process

[0124] The invention also relates to a method for preparing a material comprising a step of mixing a hydrocarbon binder and a polymeric additive according to the invention at a temperature between 120 and 180°C.

[0125] The process may also include a step of adding the additives used in the road sector as presented above.

[0126] These additional adjuvants can be added to the additive according to the invention, prior to the mixing step with the binder.

[0127] Alternatively, these additional additives can be added to the material according to the invention.

[0128] In other words, the different adjuvants can be added in any order, or even simultaneously.

[0129] The invention also relates to the product obtained by the preparation process defined above.

[0130] Use of the material

[0131] The invention also relates to the use of the material according to the invention for the preparation of a hydrocarbon binder-based asphalt mix.

[0132] In another embodiment, the material according to the invention comprising bitumen is used for the preparation of shingle.

[0133] In another embodiment, the material according to the invention is used for the preparation of sealing putty.

[0134] Coated

[0135] The invention also relates to an asphalt mix comprising a material according to the invention, aggregates and optionally a mineral filler.

[0136] Preferably, the binder of the material is a natural paraffinic or naphthenic bituminous binder.

[0137] Mineral fillers consist of particles smaller than 0.063 mm and possibly aluminosilicates or aggregates from recycled materials, sand with particles between 0.063 mm and 2 mm, and possibly gravel with particles larger than 2 mm and possibly aluminosilicates. The term "aggregates" here refers to all aggregates usable for the production of bituminous mixes, particularly for road construction, as defined, for example, in standards NF EN 13043 (2003) and XP P18-545 (2004), ranging from fines to gravel.The aggregates that can be used for the production of bituminous mixtures include in particular natural mineral aggregates from quarries or gravel pits, recycled products resulting in particular from the recycling of materials recovered during road repairs, including asphalt aggregates, manufacturing waste, aggregates from the recycling of road materials including concrete, slags in particular dross, shales in particular bauxite or corundum, rubber powders from the recycling of tires in particular, as well as mixtures thereof in all proportions.

[0138] In this case, the mineral aggregates used in asphalt mixes are generally quarry products and are increasingly used in combination with recycled aggregates from previously manufactured asphalt mixes. Such recycled aggregates are known generically as reclaimed asphalt pavement (RAP) or asphalt mix aggregates (AMA), defined and characterized according to standard NF EN 13108-8.

[0139] AEs may include other common components, such as, by way of limiting examples, organic and inorganic fibers (e.g. glass, metal or carbon fibers, cellulose, cotton, etc.), polymers (e.g. polypropylenes, polyesters, poly(vinyl alcohols)s, polyamides, polyurethanes, polyureas, ethylene-vinyl acetate (EVA) and styrene-butadiene-styrene (SBS) copolymers).

[0140] Reclaimed or recycled aggregates, commonly called reclaimed asphalt pavement (RAP), are of particular interest. These aggregates result from the milling, or other grinding methods, of previous asphalt mixes, which are generally damaged and require replacement. These recycled aggregates contain bitumen used as a binder during the initial production.

[0141] Preferably, the asphalt according to the invention comprises from 5% to 100% by mass of recycled asphalt aggregates relative to the total mass of aggregates, preferably 10% to 70% by mass.

[0142] Other sources of bituminous products that can also be recycled in the manufacture of asphalt include, for example, roofing products (e.g., shingles or waterproofing membranes, as well as waste from their production), thermal insulation or soundproofing materials.

[0143] The present invention is applicable to all products composing road pavements corresponding to the following European standards:

[0144] - Bituminous coatings according to standard NF EN 13108-1,

[0145] - Very thin bituminous concretes according to standard NF EN 13108-2,

[0146] - Draining Bituminous Concretes according to standard NF EN 13108-7.

[0147] Preferably, the asphalt mix according to the invention comprises 90% to 98% aggregates by mass relative to the total mass of asphalt. Asphalt mix preparation process

[0148] The invention also relates to a process for preparing asphalt based on hydrocarbon binder comprising a step of mixing the material according to the invention, aggregates and possibly mineral fillers.

[0149] Several methods for preparing asphalt mixes based on hydrocarbon binders are possible.

[0150] According to one embodiment, it is possible to prepare a hydrocarbon binder-based asphalt by mixing a material according to the invention, which includes bitumen as a binder, aggregates, possibly recycled aggregates, and possibly mineral fillers.

[0151] Hot mix asphalt, also known as low-temperature or low-temperature hydrocarbon binder mixes, can be manufactured at temperatures ranging from 60°C to 180°C. More commonly, manufacturing temperatures are between 120°C and 180°C. Several advantages are observed by adding at least one polymeric additive according to the invention:

[0152] -For hot manufacturing, transport times can be extended due to increased material handling in the presence of the polymer additive.

[0153] -For manufacturing at lower temperatures, the workability of the hydrocarbon binder-based asphalt is maintained at a lower temperature.

[0154] In general, the present invention makes it possible to delay the rise in cohesion of the previously described material, resulting in increased workability at lower temperatures, an increase in material transport times, and allows for an increase in construction seasons by preserving workability properties in the presence of low outside temperatures.

[0155] According to another embodiment, it is possible to prepare a hydrocarbon binder-based coating by mixing a material according to the invention, which includes an oil as a binder, recycled aggregates, and optionally mineral fillers.

[0156] Use of asphalt

[0157] The invention also relates to the use of hydrocarbon binder-based asphalt for the manufacture of road surfaces, sidewalks or other urban developments, and waterproofing layers for structures and buildings.

[0158] Road surface preparation method. According to one embodiment, it is possible to prepare a road surface comprising the following successive steps:

[0159] 1) mixing of the bituminous material as defined above with aggregates at a temperature between 120°C and 180°C,

[0160] 2) spreading of the bituminous coating at a temperature lower than that of the mixture.

[0161] The process may include an additional step of compacting the bituminous mixture after spreading.

[0162] Preferably, the road surface is a wearing course.

[0163] The invention also relates to the use of bituminous mix for the manufacture of road surfacing, sidewalks or other urban developments, and waterproofing layers for structures and buildings.

[0164] Examples

[0165] Example 1: Evaluation of the workability of semi-coarse granular asphalt concrete (BBSG) mixes without asphalt aggregate, with or without additives

[0166] Preparation of bituminous mixtures

[0167] The comparative bituminous mixes and those according to the invention were prepared in accordance with standard NF-EN-12697-35 concerning the preparation of bitumens, additives, aggregate drying, and granular skeleton according to the chosen structure. The ingredients and their contents are listed in Table 1 below. The contents are expressed as mass percentages.

[0168] Table 1

[0169] BBSG 1 is Semi-Grainy Bituminous Concrete silico-calcareous with the following granular formulation: 30.6% 0 / 2; 27.3% 2 / 6 and 42% 6 / 10, the aggregates of which come from the SDC quarry.

[0170] The filler is a PKA limestone petrography filler composed of 90% fines passing at 63pm, marketed by the Provençale company.

[0171] The binder is a grade 35 / 50 bitumen marketed by the company Repsol.

[0172] The additive binder is a grade 35 / 50 bitumen marketed by the company Repsol, containing the additives PPG 425 or PPG 2000 in the proportions indicated in table 1.

[0173] PPG 425 is a polypropylene glycol type polymer with a number-average molar mass of 425 g / mol 1 and presenting a hydroxyl value of 264 mg KOH / g marketed by the company Sigma Aldrich.

[0174] PPG 2000 is a poly(propylene glycol) polymer with a number-average molar mass of 2000 g / mol 1 and presenting a hydroxyl value of 56 mg KOH / g marketed by the company Sigma Aldrich.

[0175] The hydroxyl number of the additive per kg of binder in each composition is calculated using the equations described above.

[0176] As an example, the calculation is detailed for composition 2. The hydroxyl number, expressed in milligrams of potassium hydroxide required to neutralize the free hydroxyl groups contained in one gram of additive, is as follows:

[0177] This index then allows us to calculate the hydroxyl index, expressed in grams of potassium hydroxide required to neutralize the free hydroxyl groups contained in one gram of additive relative to one kilogram of binder: εoff = 264 x 0.005 x 10 3 = 1320 mg KOH / g

[0178] Evaluation of the workability of bituminous mixes. The previously prepared bituminous mixes were tested to evaluate their workability. A "Nynas" workability tester was used for this purpose, with tests carried out according to an experimental method similar to the NF-EN-12697-53 standard and described below.

[0179] The dimensions of the mold used are as follows: 22*30*10 (6600 cm 3 A void content of 30% is targeted, corresponding to the void ratio of a loosely packed asphalt mix. The final asphalt mass is obtained by the following calculation: Mass E nrobé = M hearing x MVRe x Optimal Compactness Mass E nrobé means the mass of final asphalt mix expressed in kg. Mouie means the volume of the mold expressed in m³ 3 It is equal to 6600 cm 3 .

[0180] MVRe means the actual density expressed in kg.crrr 3 , it is obtained according to the standard NF EN 12697-5.

[0181] The optimal compactness is expressed as a percentage. The target optimal compactness is 70% (30% void space).

[0182] The asphalt mix is ​​placed in the mold after production and compacted by percussion to achieve a density of 70%. The mold is then positioned in the Nynas handling tester. A hydraulic cylinder, coupled with a paddle and a force sensor, moves a volume of asphalt with a density of 70%. After this horizontal pushing of the asphalt, simulating manual work on a construction site, the maximum decohesion force reached by the sensor is displayed on the device. The temperature of the asphalt is measured using a thermocouple. The asphalt is then returned to its container, decoheded manually, and then placed back in the mold to take another measurement at a lower temperature.

[0183] During these measurements, uncontrolled natural cooling of the asphalt simulates construction site conditions on a laboratory scale.

[0184] At a minimum, three points at three different temperatures are recorded, allowing a force curve obtained by the sensor to be plotted as a function of the temperature measured by the thermocouple. These three minimum points must encompass a thrust force of 300 N.

[0185] A force exceeding 300 N, measured with a Nynas handling meter, is considered to pose a risk to workers. Based on this reference, it is possible to evaluate the benefit of the additive compared to a mix manufactured at 130°C without additives, with additives, and with and without asphalt aggregate.

[0186] The gain in handling is determined in °C using the following formula: The results obtained are shown in Figure 1 in the appendix and are included in Table 2 below:

[0187] Table 2

[0188] The Nynas workability curves shown in Figure 1 illustrate the force required to break up the asphalt mix as a function of temperature. Thus, the workability limits set at 300 N are reached at a lower temperature in the presence of the additive according to the invention. A workability improvement of up to 7°C between the comparative asphalt mix 1 and the asphalt mix according to the invention 3 is achieved, which can translate into additional time for spreading the asphalt on the ground.

[0189] Example 2: Evaluation of the workability of limestone bitumen (GB) aggregate mixes without asphalt concrete, with or without additives

[0190] Preparation of bituminous mixtures

[0191] The comparative bituminous mixes and those according to the invention were prepared following the standard NF-EN-12697-35 as described above.

[0192] The ingredients and their contents are listed in Table 3 below. Contents are expressed as mass percentages:

[0193] Table 3

[0194] GB1 designates Gravel Bitume 1, which is a GB type granular skeleton of calcareous petrography and of the following granular formulation: 36.3% of 0 / 2; 12.2% of 2 / 6; 21.5% of 6 / 10 and 30% of 10 / 14, whose aggregates come from the Dompierre quarry.

[0195] The filler is a PKA limestone petrography filler composed of 90% fines passing at 63 pm, marketed by the Provençale company.

[0196] The binder is grade 35 / 50 bitumen marketed by the company Repsol.

[0197] The additive binder is grade 35 / 50 bitumen marketed by the company Repsol, containing PPG 2000 in the proportions indicated in table 3.

[0198] PPG 2000 is a poly(propylene glycol) polymer with a number-average molar mass of 2000 g / mol 1 and presenting a hydroxyl value of 56 mg KOH / g marketed by the company Sigma Aldrich.

[0199] Evaluation of the workability of bituminous mixtures

[0200] The previously prepared bituminous mixtures were tested in a manner similar to the method described in Example 1.

[0201] The results are shown in Table 4 below:

[0202] Table 4

[0203] The values ​​obtained are shown in Figure 2 in the appendix.

[0204] Tests in the presence of calcareous gravel materials demonstrate the continued effectiveness of the additive according to the invention. The warm, unadditized reference mix, manufactured at 130°C (comparative example 6), remains workable up to 112°C and up to 104°C in the presence of the PPG 2000 additive (example 7 according to the invention). Adding the additive to the formulation therefore improves workability by 8°C. Example 3: Evaluation of the workability of semi-coarse granular asphalt concrete (BBSG) mixes with asphalt aggregates, with and without the additive.

[0205] Preparation of bituminous mixtures

[0206] The comparative bituminous mixes and those according to the invention were prepared following the standard NF-EN-12697-35 as described above.

[0207] The ingredients and their contents are listed in Table 5 below. Contents are expressed as mass percentages:

[0208] Table 5

[0209] BBSG 2 is a semi-coarse silico-calcareous bituminous concrete with the following granular formulation: 11.7% 0 / 2; 44.0% 2 / 6 and 44.3% 6 / 10, the aggregates of which come from the SDC quarry.

[0210] The asphalt aggregates, noted AE, are of the all-in type, they include 2% by mass of bituminous binder.

[0211] The charge is a limestone petrography filler composed of 90% fine passing at 63 pm marketed by Provençale.

[0212] The binder is a supplementary binder.

[0213] The additive binder is a top-fill binder, with the additive PPG 425 added. The mass proportions of the top-fill binder and the additive are shown in Table 5. The top-fill binder is grade 35 / 50 bitumen marketed by the company Repsol.

[0214] PPG 425 is a poly(propylene glycol) polymer with a number-average molar mass of 425 g / mol 1and presenting a hydroxyl value of 264 mg KOH / g marketed by the company Sigma Aldrich.

[0215] Evaluation of the workability of bituminous mixtures

[0216] The previously prepared bituminous mixtures were tested in a manner similar to the method described in Example 1.

[0217] The results are shown in Table 6 below:

[0218] Table 6

[0219] The values ​​obtained are shown in Figure 3 in the appendix.

[0220] Tests in the presence of asphalt pavement aggregates in the bituminous mix demonstrate the continued effectiveness of the additive according to the invention. The warm, unadditized reference mix, manufactured at 130°C (comparative example 8), remains workable up to 118°C, and up to 110°C in the presence of the PPG 425 additive (example 9 according to the invention). The addition of the additive to the formulation therefore results in an 8°C improvement in workability.

[0221] Example 4: Evaluation of the workability of semi-coarse granular asphalt concrete (BBSG) mixes without asphalt aggregates, with or without an additive

[0222] Preparation of bituminous mixtures

[0223] The comparative bituminous mixes and those according to the invention were prepared following the standard NF-EN-12697-38 as described above.

[0224] The ingredients and their contents are listed in Table 7 below. Contents are expressed as mass percentages:

[0225] Table 7

[0226] BBSG 1 is a semi-coarse silico-calcareous bituminous concrete with the following granular formulation: 30.6% 0 / 2; 27.3% 2 / 6 and 42% 6 / 10, the aggregates of which come from the SDC quarry.

[0227] The filler is a PKA limestone petrography filler composed of 90% fines passing at 63pm, marketed by the Provençale company.

[0228] The binder is grade 35 / 50, marketed by the company Repsol.

[0229] The additive binder corresponds to grade 35 / 50 bitumen marketed by the company Repsol, with the addition of the tribloc additive OE-OP-OE, the dibloc A additive, the dibloc B additive or the PPG 2000 additive. The mass proportions of the additive are shown in Table 7.

[0230] The OE-OP-OE triblock polymer is a poly(oxyethylene-oxypropylene-oxyethylene) type polymer with a mass average molar mass of 3600 g / mol 1 and presenting a hydroxyl value of 31 mg KOH / g marketed by the company Arkema.

[0231] Dibloc A is a 19OP-55OE dibloc polymer, of the poly(oxypropylene-oxyethylene) type, with a mass average molar mass of 3500 g / mol. 1 and exhibiting a hydroxyl value of 32 mg KOH / g. Dibloc B is a 55OP-19OE dibloc polymer, of the poly(oxypropylene-oxyethylene) type, with a mass average molar mass of 4000 g / mol. 1and exhibiting a hydroxyl value of 28 mg KOH / g.

[0232] PPG 2000 is a poly(propylene glycol) polymer with a number-average molar mass of 2000 g / mol 1 and presenting a hydroxyl value of 56 mg KOH / g marketed by the company Sigma Aldrich.

[0233] Evaluation of the workability of bituminous mixtures

[0234] The previously prepared bituminous mixtures were tested in a manner similar to the method described in Example 1.

[0235] The results are shown in Table 8 below:

[0236] Table 8

[0237] The values ​​obtained are shown in Figure 4 in the appendix.

[0238] Tests conducted with different chemical structures of polyethers in the bituminous mix demonstrate improved effectiveness of the additive according to the invention. The non-additive reference mix, manufactured at 130°C (comparative example 10), remains workable up to 120°C, up to 113°C in the presence of the OE-OP-OE triblock additive (comparative example 11), and up to 108°C in the presence of the PPG 2000 additive (example 14 according to the invention). Adding the additive to the formulation therefore results in a 12°C improvement in workability.

Claims

Demands 1. Material for bituminous mixtures, comprising a hydrocarbon binder and at least one polymeric additive of the following formula (1): R-[(OA) m ]n-OH (1) in which: - n represents the valence of the group R, n denotes a number between 1 and 6, - R represents a hydrogen atom, a linear or branched hydrocarbon chain, saturated or unsaturated, comprising from 1 to 50 carbon atoms, possibly bearing one or more hydroxyl groups, a hydrocarbon ring, monocyclic or polycyclic, aliphatic or aromatic, of 4 to 10 vertices, possibly comprising one or more heteroatoms chosen from oxygen, nitrogen and sulfur, - OA represents an oxyalkylene chain chosen from oxyethylene (OE), oxypropylene (OP), oxybutylene (OB) and mixtures of two or more of them, - m denotes an integer between 3 and 500, preferably between 3 and 300, more particularly between 3 and 220, the content of additive in the binder being such that the hydroxyl index of the additive per kg of binder is between 200 and 700 g KOH / kg.

2. Material according to claim 1, characterized in that the polymeric additive of formula (1) comprises 0 to 170 oxyethylene, preferably 0 to 90 oxyethylene and 0 to 170 oxybutylene, preferably 0 to 90 oxybutylene and 1 to 170 oxypropylene, preferably 3 to 90 oxypropylene.

3. Material according to claim 1 or 2, characterized in that the polymeric additive has a hydroxyl number between 20 and 500 mg KOH / g.

4. Material according to any one of the preceding claims, characterized in that the polymeric additive has a number-average molar mass between 200 and 10,000 g / mol 1 , preferably between 200 and 8,000 g.mol 1and preferably between 300 and 5,000 g.mol 1 .

5. Material according to any one of the preceding claims, characterized in that the R group of the formula (1) of the polymeric additive is selected from a hydrogen atom, a methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl and dodecyl group.

6. Material according to any one of the preceding claims, characterized in that when the polymeric additive of formula (1) comprises oxypropylene (OP) units, and oxyethylene (OE) and / or oxybutylene (OB) units, then the number of oxypropylene (OP) units is greater than the sum of the number of oxyethylene (OE) and / or oxybutylene (OB) units.

7. Material according to any one of the preceding claims, characterized in that the polymeric additive of formula (1) comprises oxyethylene (OE) and oxypropylene (OP) units, the oxypropylene units being in the majority.

8. Material according to any one of the preceding claims, characterized in that the polymeric additive of formula (1) is a diblock polymer.

9. Material according to any one of claims 1 to 5, characterized in that the additive is a homopolymer of oxypropylene.

10. Material according to any one of the preceding claims, characterized in that the hydrocarbon binder is a bituminous binder, a synthetic binder or an oil.

11. Material according to any one of the preceding claims, characterized in that it comprises from 0.02 to 5% by mass, relative to the mass of the hydrocarbon binder, of said polymeric additive, preferably from 0.05 to 1.5% by mass, and preferably from 0.075% to 0.5% by mass.

12. Use of the material as defined in any of the preceding claims for the preparation of an asphalt mix.

13. Asphalt based on hydrocarbon binder comprising a material as defined in any one of claims 1 to 11 and aggregates comprising recycled asphalt aggregates.

14. Method for manufacturing a hydrocarbon binder-based asphalt mix comprising a step of mixing the material as defined in any one of claims 1 to 11 with aggregates at a temperature between 120°C and 180°C.

15. Use of asphalt based on hydrocarbon binder for the manufacture of road surfaces, sidewalks or other urban developments, waterproofing layers of structures and buildings.

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