Use of waxes as an Anti-surface-filming agent

Abstract

The present invention relates to the use of a wax, as an anti-surface-filming adjuvant for a hydraulic composition or a hydraulic binder composition. The present invention also relates to a method for reducing, or even eliminating, the appearance of a surface film on a hydraulic composition, comprising adding a wax in the mass or on the surface of a hydraulic composition, or in the hydraulic binder composition of the hydraulic composition.

Description

[0001] Use of waxes as a surface anti-dandruff agent

[0002] The present invention relates to the use of a wax, preferably in the form of an emulsion, as a surface anti-film-forming agent for a hydraulic composition or a hydraulic binder composition. It therefore involves using a wax, preferably in the form of an emulsion, to improve the surface adhesion of cementitious materials, and preferably of self-leveling screeds.

[0003] In order to flatten, level or surface a support and / or coat a heated floor to then receive the upper layers (all types of support: tiles, flexible flooring, floating or glued parquet etc.), it is common practice to pour relatively fluid hydraulic compositions, called mortar screeds on the floor.

[0004] After pouring, setting, and drying of these cementitious materials, a surface film a few hundredths of a millimeter thick, composed of calcium hydrate particles, frequently appears. This thin film exhibits unsightly wrinkles and flakes and significantly reduces the adhesion of finishing materials intended to be applied to the surface, such as plaster, ceramics, paints, wood, various coatings, or other materials.

[0005] This type of surface film is also observed on the surface of other hydraulic compositions, such as self-compacting concrete (SCC), a concrete capable of placing itself in even complex and crowded formworks under the sole effect of gravity.

[0006] It is important to note that the formation of a surface film is a different phenomenon from efflorescence. Efflorescence is caused by the transport of calcium ions to the surface of the concrete through water-filled pores. Upon contact with atmospheric carbon dioxide, white calcium carbonate crystals form on the surface. Efflorescence does not alter the mechanical strength or porosity of the concrete, only its appearance. In contrast, a surface film results from the rise of very fine particles of calcium hydrates to the surface of the screed or concrete and must be removed to ensure proper adhesion.Thus, the processes involved in the appearance of these two phenomena are totally different, and their consequences are also different because the disadvantage of efflorescence is purely aesthetic (no consequences in terms of performance), whereas the surface film must be eliminated so that the surface of the concrete or screed does not lack adhesion performance.

[0007] To ensure sufficient adhesion of the finishing materials to the surface, it is necessary to brush, scrape, or sand the surface of these cementitious materials before beginning the finishing work to remove the film. This work is lengthy and expensive, generally resulting in an extension of the project completion time.

[0008] To address this problem, FR 2948930 is known to use at least one C8-C22 fatty alcohol and at least one anti-caking agent, and FR 2987044 is known to use a C8-C22 fatty alcohol and an oil.

[0009] However, these anti-skinning agents are primarily intended for screeds, including anhydrite screeds containing calcium sulfate, which do not require the use of a shrinkage inhibitor. Yet, these anti-skinning agents have proven relatively ineffective when the hydraulic composition also includes a shrinkage inhibitor, as shown in Example 7 of FR 2948930. Shrinkage inhibitors are used when the hydraulic composition has a high water content, as it is then much more susceptible to shrinkage. This is the case with typical self-leveling screeds (mortar floor screeds), or with hydraulic compositions based on hydraulic binders in which some of the clinker is replaced by mineral additions, which often have a higher water demand than clinker.

[0010] One aim of the invention is therefore to propose new anti-surface film adjuvants that are compatible with anti-shrinkage agents, and that are therefore particularly suitable for hydraulic compositions comprising a fairly high water content.

[0011] For this purpose, the invention relates to the use of a wax as an anti-film surface adjuvant for a hydraulic composition or a hydraulic binder composition.

[0012] The wax is used as such or is included in an adjuvant composition (and it is then the adjuvant composition including the wax that is used as an anti-surface film adjuvant of a hydraulic composition or a hydraulic binder composition).

[0013] According to one embodiment, the use according to the invention comprises adding the wax (or the additive composition) to the mass of the hydraulic composition or to the surface of the hydraulic composition, preferably to the mass of the hydraulic composition. When added to the mass of the hydraulic composition (at the time of mixing), the wax and / or the additive composition comprising the wax may be in liquid or powder form. When added to the surface of the hydraulic composition, the wax and / or the additive composition comprising the wax is preferably in liquid form.

[0014] According to another embodiment, the use according to the invention includes the addition of the wax or the adjuvant composition to the hydraulic binder composition, before mixing (i.e. before the preparation of a hydraulic composition comprising said hydraulic binder composition).

[0015] When added to the hydraulic binder composition, the wax and / or the additive composition including the wax are preferably in powder form.

[0016] Preferably, the use according to the invention makes it possible to reduce, or even eliminate, the appearance of a film on the surface of the hydraulic composition (in particular during the setting of the hydraulic composition).

[0017] Preferably, the use according to the invention makes it possible to improve, preferably by at least 30%, the surface adhesion of a cementitious material obtained from the hydraulic composition, and preferably from a self-placing screed.

[0018] Surface adhesion can be determined according to the protocol defined in technical document DT 99046-01 (2023).

[0019] - Production of 40x40x5 cm slabs of hydraulic composition o Pouring of the screed according to the manufacturer's instructions (passage of the bar in

[0020] 1 or 2 times, ...) o Allow the screed to dry in the mold for 27 days in a laboratory environment (20 + / - 2°C) and 50% < RH < 70%

[0021] - Preparation for surface adhesion measurement: o If adhesion assessment is to be performed after sanding, then sand the screed surface 27 days later using an orbital sander with 36-grit sandpaper until the first grains of sand appear. o Cut the areas for bonding the square metal tensile strength pieces, measuring (50+1) mm x (50+1) mm (minimum thickness of 10 mm), to a cutting depth of (10+5) mm. o Carefully remove dust from the surface by vacuuming and then blowing. o Bond the metal tensile strength pieces to the surface of the test slab using Araldite 2014-2 (or 2012). o Carrying out the pull-out resistance test on each metal tensile part 24h after the bonding of the tensile parts using a dynamometer (dynamometer allowing to exert a tensile force of 125 N / s or a load increase of (0.05 ± 0.01) MPa / s).o The surface adhesion by traction (A) of the hydraulic composition studied is then determined by the following formula:.

[0022] A = L / S

[0023] A: tensile strength value expressed in N / mm 2 (MPa) L: total force, expressed in Newtons;

[0024] S: bonding surface, i.e. 2500 mm2 in the case of 5 cm side tees.

[0025] The invention also relates to a method for reducing, or even eliminating, the appearance of a surface film of a hydraulic composition, comprising the addition of a wax, in the mass or on the surface of a hydraulic composition, or in the hydraulic binder composition of the hydraulic composition.

[0026] The wax is used as such or is included in an adjuvant composition (and it is then the adjuvant composition including the wax that is added to the mass or surface of a hydraulic composition, or to the hydraulic binder composition of the hydraulic composition).

[0027] Preferably, the addition of the wax or the adjuvant composition comprising at least one wax, is in the mass of the hydraulic composition.

[0028] When added to the mass of the hydraulic composition (at the time of mixing), the wax and / or the additive composition containing the wax may be in liquid or powder form. When added to the surface of the hydraulic composition, the wax and / or the additive composition containing the wax is preferably in liquid form.

[0029] When added to the hydraulic binder composition, the wax and / or the additive composition including the wax are preferably in powder form.

[0030] Preferably, the method according to the invention is for improving, preferably by at least 30%, the surface adhesion of a cementitious material obtained from the hydraulic composition, and preferably from a self-placing screed.

[0031] It is understood that all embodiments of the following description apply equally to the use or method according to the invention. Wax

[0032] The wax of the invention comprises, or even consists of, a mixture of hydrocarbons. These hydrocarbons are linear or branched, saturated and / or unsaturated, with general formulas C n H2n+2 and C n H2n, in which n is an integer greater than or equal to 15, preferably greater than or equal to 20, preferably between 20 and 120.

[0033] Preferably, at least 50% by mass of the wax hydrocarbons are C25 or higher (contain at least 25 carbon atoms). In other words, preferably, the wax hydrocarbon mixture comprises at least 50% by mass of C25 or higher compounds.

[0034] Preferably, the hydrocarbon mixture of the wax (or even the wax itself) comprises (or consists of), relative to its total mass:

[0035] - 20% to 50% by mass, preferably 20% to 40% by mass, of C20-C25 hydrocarbons,

[0036] - 50% to 80% by mass, preferably 60% to 80% by mass, of C26-C35 hydrocarbons, and

[0037] - from 0% to 5% by mass of hydrocarbons in C36 or higher.

[0038] Preferably, the melting point of the hydrocarbon mixture of the wax (or even the wax) is between 40°C and 75°C, preferably between 50°C and 70°C.

[0039] Preferably, the density of the hydrocarbon mixture of the wax (or even the wax itself) is between 0.85 and 0.98.

[0040] Preferably, the hydrocarbon mixture of the wax (or the wax itself) is in the form of particles, preferably having a D50 particle size between 0.8 and 2.0 pm, and / or a D10 particle size strictly less than 1.0 pm, preferably between 0.01 pm and 1.0 pm (exclusive), and / or a D90 particle size between 1.0 and 5.0 pm.

[0041] The device used to measure particle size is, for example, a MALVERN Mastersizer 2000 laser particle size analyzer. The measurement was performed in liquid form using deionized water.

[0042] Laser particle size analysis measures the particle size distribution of a material in powder, suspension, or emulsion form. The measurements are based on the principle of laser beam diffraction by particles suspended in a carrier liquid. The laser beam, with a wavelength of 632 nm, is generated from a helium-neon source. This beam is directed onto a measuring cell through which the particles / droplets suspended in the carrier medium pass. The particle diameter range detected by this device extends from 0.01 pm to 1000 pm.

[0043] The results obtained allow us to plot the volumetric percentage of particles / droplets as a function of their diameter, for a particle size distribution ranging from 0.01 to 1000 µm. The values ​​most often referenced are the following characteristic diameters of the particle size distribution:

[0044] - D10: Diameter below which 10% (by volume) of the total population lies

[0045] - D50: Diameter below which 50% (by volume) of the total population lies

[0046] - D90: Diameter below which 90% (by volume) of the total population is located.

[0047] The wax can therefore be in the form of a powder comprising, or even consisting of, the particles of the hydrocarbon mixture, or be in liquid form, for example in the form of a solution, suspension or emulsion comprising the particles of the hydrocarbon mixture.

[0048] Preferably, the wax is in the form of a direct or reverse emulsion, preferably direct, preferably aqueous, preferably stabilized by one or more nonionic, cationic, anionic, nonionic and anionic, or nonionic and cationic surfactant systems. Preferably, the paraffinic wax is in the form of an emulsion stabilized by one or more nonionic surfactant systems. Alternatively, the paraffinic wax is in the form of an emulsion stabilized by one or more anionic surfactant systems.

[0049] Preferably, an emulsifying agent may be introduced to prevent coalescence of the emulsion and to stabilize it. Such an agent may be anionic or non-ionic, preferably non-ionic. The emulsifier is selected, in particular, from among C8 to C22 fatty acids neutralized by an amine (for example, triethanolamine), sulfonated compounds, sulfated compounds, phosphonated compounds, phosphated compounds, fatty alcohols, sorbitan esters, ethylene oxide-propylene oxide copolymers, or others.

[0050] Alternatively, the wax may be in powder form. In this embodiment, the wax preferably consists of the hydrocarbon mixture as defined above. The wax may alternatively further comprise a filler or anti-caking agent, for example, oxides, silicates, and carbonates such as calcium carbonates, kaolin, alumina, or silica. Preferably, in the use or method according to the invention, the wax comprises a mixture of hydrocarbons and is added to the hydraulic binder composition or to the hydraulic composition in an amount corresponding to 0.01% to 5.0% by mass of the hydrocarbon mixture of the wax, preferably 0.02% to 2.0% by mass, preferably 0.05% to 1.0%, preferably 0.08% to 0.8% by mass, preferably 0.10% to 0.6% by mass, relative to the total dry mass of the hydraulic binder composition.When wax is added to the hydraulic composition, the wax content is therefore expressed relative to the dry mass of the hydraulic binder composition included in the hydraulic composition.

[0051] Since wax content is expressed by the content of hydrocarbon mixture contained in the wax, these contents are valid whether the wax is in powder or liquid form.

[0052] These contents are particularly valid when wax (or the additive composition including wax) is added to the hydraulic binder composition, or added in bulk to the hydraulic composition.

[0053] In the embodiment in which the wax (or the wax-containing additive composition) is added to the surface of the hydraulic composition, the wax (or the wax-containing additive composition) is preferably sprayed onto the surface of the fresh hydraulic composition (immediately after pouring). Preferably, the amount of wax (or the wax hydrocarbon mixture) deposited per unit area is, in particular, 50 to 300 g / m². 2 , particularly between 100 and 250 g / m 2 .

[0054] Composition of hydraulic binder

[0055] A hydraulic binder composition comprises at least one compound or mixture of compounds having the property of hydrating in the presence of water and whose hydration makes it possible to obtain a solid having mechanical characteristics.

[0056] The hydraulic binder composition may include, in particular, a cement conforming to standard EN 197-1 (2012), specifically a CEM I, CEM II, CEM III, CEM IV or CEM cement

[0057] V; a cement conforming to standard EN 197-5 (2021), in particular a CEM II-C / M or CEM cement

[0058] VI; a cement according to standard EN 197-6:2023, a super-sulfated cement according to standard EN 15743+A1 (2015), a binder as described by standard EN 206+A2:2021 + FD P18-480:2022, a binder certified according to ETA / ETE (EOTA) (European certification), a calcium sulfate-based binder covered by EN 13454-1, a binder certified by ETPM; and a binder certified by a technical opinion.

[0059] The composition of hydraulic binder may therefore include one or more mineral additions. The term "mineral additions" refers to slags (as defined in EN 197-1:2012 paragraph 5.2.2 and EN 15167-1:2006), steelmaking slags, pozzolanic materials (as defined in EN 197-1:2012 paragraph 5.2.3), fly ash (as defined in EN 197-1:2012 paragraph 5.2.4), calcined shale (as defined in EN 197-1:2012 paragraph 5.2.5), or silica fume (as defined in EN 197-1:2012 paragraph 5.2.7 or EN 197-5 paragraph 5), calcined clays, limestones or mixtures thereof.

[0060] The hydraulic binder composition may also include calcium sulfate, as defined in EN 197-1:2012 paragraph 5.4. Preferably, the hydraulic binder composition may also include 0 to 5% by mass of calcium sulfate to regulate setting, preferably 1% to 5% by mass of calcium sulfate, the proportions being by mass relative to the total mass of the hydraulic binder composition.

[0061] Calcium sulfate can be gypsum (calcium sulfate dihydrate, CaSO4 2H2O), hemihydrate (CaSO4 1 / 2H2O), or anhydrite (anhydrous calcium sulfate, CaSO4) or any mixture of these.

[0062] According to one embodiment, the hydraulic binder composition has a quantity of clinker less than or equal to 80% by mass, preferably from 0 to 80% by mass, relative to the total mass of the hydraulic binder composition.

[0063] The hydraulic binder composition therefore preferably includes at least one mineral material other than clinker, and possibly clinker.

[0064] Preferably, the hydraulic binder composition comprises, relative to the total mass of the hydraulic binder composition, 20% to 100% by mass of a mineral material other than clinker, preferably 20% to 99.99% by mass, preferably 30% to 99% by mass, preferably 40% to 99% by mass, preferably 45% to 95% by mass, preferably 50% to 95% by mass, and preferably 60% to 90% by mass. If the hydraulic binder composition comprises several mineral materials other than clinker, these amounts correspond to the total content of mineral materials other than clinker.

[0065] When the hydraulic binder composition includes clinker, the clinker is present in a content preferably ranging from 0.01% to 80% by mass, preferably from 1% to 70% by mass, preferably from 1% to 60% by mass, preferably from 5% to 55% by mass, preferably from 5% to 50% by mass, preferably from 10% to 40% by mass, relative to the total mass of the hydraulic binder composition. The clinker is in particular Portland or sulfoaluminate clinker, preferably Portland clinker as defined in the book "Cernent Chemistry" (Harry F.W. Taylor, 2nd edition, Academy Press, 1990).

[0066] The mineral material other than clinker can be any material that can be used in the composition of a hydraulic binder.

[0067] Mineral materials other than clinker suitable for the present invention include, for example, calcium sulfates, mineral additions (such as calcined clays, metakaolins, limestones, natural or artificial pozzolans, silica fumes, fly ash, granulated blast furnace slags, calcined shales), crystallized, expanded, vitrified blast furnace slags (granulated or pelletized), conversion steel slags, electric arc furnace carbon steel production slags, ladle slags, crushed shales, quartz, aluminous cements, sulfoaluminate cements, recycled glass, zeolites, diatomaceous earths, recycled concrete fines from deconstruction, and any mixture thereof.

[0068] In particular, the mineral material other than clinker is chosen from calcium sulfates and mineral additions, more particularly from calcium sulfate, calcined clays, limestones, natural or artificial pozzolans, fly ash and blast furnace slags, even more particularly from calcium sulfates, calcined clays, limestones, natural or artificial pozzolans, and any mixture thereof, advantageously from calcium sulfates, calcined clays and limestones.

[0069] Hydraulic composition

[0070] A hydraulic composition typically includes:

[0071] - a hydraulic binder composition,

[0072] - water,

[0073] - possibly an aggregate, and

[0074] - possibly a mineral supplement.

[0075] Hydraulic compositions include, for example, compositions of concrete, screed or mortar.

[0076] The hydraulic binder composition as defined above, according to any embodiment.

[0077] The term "aggregates" refers to a collection of mineral grains with an average diameter between 0 and 125 mm. Depending on their diameter, aggregates are classified into one of the following six categories: fillers, fine sands, sands, gravels, crushed stone, and ballast (EN standards).

[0078] 12620 and EN 13242+A1). The most commonly used aggregates are: fines, with a diameter of less than 0.063mm, sands with a diameter between 0.063 and 6.3 mm, gravels with a diameter greater than 6.3 mm, and small gravels with a diameter between 2 mm and 63 mm.

[0079] Sands are therefore included in the definition of aggregate according to the invention.

[0080] The fines can notably be of calcareous or dolomitic origin.

[0081] The term "mineral additions" refers to slags (as defined in EN 197-1:2011 paragraph 5.2.2 and EN 15167-1:2006), steelmaking slags, and pozzolanic materials (as defined in EN 197-1:2011 paragraph 5.2.2).

[0082] 5.2.3), fly ash (as defined in standard EN 197-1:2011 paragraph

[0083] 5.2.4), calcined shale (as defined in standard EN 197-1:2011 paragraph

[0084] 5.2.5), or silica fumes (as defined in standard EN 197-1:2011 paragraph 5.2.7 or standard EN 197-5 paragraph 5), limestones or mixtures thereof.

[0085] The hydraulic composition of the use or method according to the invention may further include microfibers and / or macrofibers, for example:

[0086] - synthetic fibers, for example polypropylene, polyethylene, polyvinyl alcohol, polyolefins, polyacrylonitrile,

[0087] - plant fibers, for example cellulose and hemp fibers,

[0088] - metallic fibers

[0089] - fiberglass,

[0090] - carbon fibers,

[0091] - recycled fibers.

[0092] Preferably, the hydraulic composition has a water / cement mass ratio greater than or equal to 0.45, preferably greater than or equal to 0.50, preferably greater than or equal to 0.60, preferably between 0.50 and 1.5.

[0093] The mass ratio e / c corresponds to the ratio between the mass of water, preferably the effective mass of water, of the hydraulic composition and the mass of the hydraulic binder composition (excluding any mineral additions added in addition to the hydraulic binder, in particular excluding calcareous or siliceous fillers) included in the hydraulic composition.

[0094] According to one embodiment, the hydraulic composition is a self-leveling screed. Anti-shrinkage agent

[0095] According to one embodiment, the wax is used in combination with at least one anti-shrinkage agent.

[0096] In particular, the anti-shrinkage agent is present in the hydraulic binder composition or the hydraulic composition, preferably in the hydraulic composition.

[0097] Alternatively or in addition, the anti-shrinkage agent may be added to the hydraulic composition or to the hydraulic binder composition, preferably to the hydraulic composition, after the addition of the wax (or the adjuvant composition including the wax).

[0098] A shrinkage inhibitor is an admixture used to compensate for the shrinkage of concrete or mortar during setting. It can be a swelling agent (shrinkage compensator) or act on the surface tension of the water in the hydraulic composition.

[0099] The anti-withdrawal agent may preferably be chosen from:

[0100] - glycols, such as hexylene glycol, neopentyl glycol, diethylene glycol butyl ether or butyl diglycol, triethylene glycol monobutyl ether or butyl triglycol, tetraethylene glycol monobutyl ether or butyl tetraglycol, dipropylene glycol methyl ether, dipropylene glycol n-butyl ether, dipropylene glycol, polyethylene glycol, polypropylene glycol, polypropylene glycol-polyethylene glycol mixtures, alkyl ethers of polyalkylene glycols, in particular neopentyl glycols,

[0101] - polyols, particularly glycerin or erythritol,

[0102] - alkoxylated polyols, in particular alkoxylated glycerin or alkoxylated erythritol,

[0103] - alkylated alkanolamines,

[0104] - carboxylic acid esters of polyalkylene glycols, in particular fatty acid esters of polyalkylene glycols,

[0105] - fatty acid esters, in particular isobutyloleate or vegetable oils.

[0106] - alkanolamines, particularly 2-(Butylamino)ethanol,

[0107] - levulinic acid and the levulinate family (salts or esters of levulinic acid),

[0108] - alkyl polyethers,

[0109] - polyethers,

[0110] - ethylene oxide and propylene polymers.

[0111] Glycols can be in liquid or solid form, and sometimes deposited on an inorganic medium. The inorganic medium can be gypsum, preferably in anhydrite form, calcium oxide, calcium dihydroxide, calcium sulfoaluminate, calcium carbonate, magnesium oxide, magnesium carbonate, fly ash, an absorbent or superabsorbent polymer, sodium polyacrylate, titanium dioxide, microsilica, calcined clays, metakaolin, a zeolite, graphene oxide.

[0112] The anti-shrinkage agent can also be a shrinkage compensator such as CaO, MgO, anhydrite, sulfoaluminate, anhydrous calcium sulfate, calcium sulfoaluminate, or ettringitic systems based on calcium aluminate and calcium sulfate.

[0113] Preferably, the mass quantity of anti-shrinkage agent per cubic meter of hydraulic composition ranges from 1 to 50 kg / m³. 3 preferably between 3 and 40 kg / m 3 .

[0114] If several (at least two) anti-withdrawal agents are present, the above content ranges refer to the total content of all anti-withdrawal agents.

[0115] Additional additives

[0116] Other additional additives may be used within the scope of the present invention. These additional additives may be selected by those skilled in the art from among the typical additives found in hydraulic binder compositions and hydraulic compositions. These include, in particular: water-reducing or high-reducing water agents; rheological agents; surfactants; carboxylic acids or their salts such as acetic, adipic, gluconic, oxalic, citric, maleic, lactic, tartaric, malonic acids and mixtures thereof; antifoaming agents; air-entraining agents; grinding agents (including ethylene glycol oligomers or propylene glycol oligomers or mixtures thereof, and alkanolamines); and setting retarders.hardening and setting accelerators such as glycerols, formic acid, calcium salts (e.g. calcium chloride, calcium thiocyanate, calcium nitrite, calcium formate and calcium nitrate), lithium salts, aluminum salts, magnesium salts, sodium salts; alkali or alkaline earth metal or aluminum salts; inorganic nanoparticles, e.g. silica or alumina nanoparticles, calcium carbonate nanoparticles, calcium hydrosilicate (HSC) nanoparticles, and any mixture thereof.

[0117] These additional additives can each independently be present either in the hydraulic binder composition or in the hydraulic composition, and / or can each independently be added to the hydraulic composition or to the hydraulic binder composition after the addition of the wax (or the additive composition containing the wax). Each of these additives can also be both present in the hydraulic binder composition and then added as a supplement to the hydraulic composition containing the hydraulic binder composition. Preferably, the mass content of the additional additive(s) ranges from 0% to 5.0% by mass, preferably from 0.1% to 2.5% by mass, preferably from 0.3% to 1.5% by mass, relative to the dry mass of the hydraulic binder composition.If additional additives are added to the hydraulic composition, these contents therefore express the content of additional additives relative to the dry mass of the hydraulic binder composition included in the hydraulic composition.

[0118] If several (at least two) additional adjuvants are present, the above content ranges refer to the total content of all additional agents.

[0119] Water reducing agent or high water reducing agent

[0120] Preferably, the hydraulic composition and / or the hydraulic binder composition further comprises a water reducing agent or high water reducing agent selected from polyalkyl polycarboxylate polymers and polyalkyl phosphonate polymers, and any mixture thereof and / or the use (or method) according to the invention comprises the addition of a water reducing agent or high water reducing agent selected from polyalkyl polycarboxylate polymers and polyalkyl phosphonate polymers, and any mixture thereof, to the hydraulic composition or to the hydraulic binder composition after the addition of the wax (or the adjuvant composition comprising the wax).

[0121] Preferably, polycarboxylate polyalkoxylated polymers comprise units of formulas (I) and (II), and optionally units of formula (III), as follows: in which

[0122] - "R2" and "R3" each independently represent a hydrogen or a methyl group, - "M" each independently represents H + or a cation of valence v chosen from an alkali metal cation, an alkaline earth metal cation, a divalent or trivalent metal cation, an ammonium cation or an organic ammonium cation,

[0123] - when "M" represents H + , "v" represents 1 , and when "M" represents a cation as defined above, "v" is the valence of the cation M,

[0124] - “R7” and “R8” each independently represent a hydrogen, a methyl or a group of formula -COO(M) 1 / V with M and v as defined above,

[0125] - "m" represents 0, 1 or 2,

[0126] - "p" represents 0 or 1,

[0127] - "X" is O or NR9, "R9" representing H, a C1-C20 alkyl group, a cycloalkyl group, or an alkylaryl group, and

[0128] - “R1” represents a C1-C20 alkyl group, a cycloalkyl group, an alkylaryl group, or -[Alkyl-O] z -R6, in which the "Alkyl" of each unit [Alkyl-O] independently represents a linear or branched alkylene comprising 2 to 4 carbon atoms, and "R6" represents H, a C1-C20 alkyl group, a cyclohexyl group, or an alkylaryl group, and "z" is an integer from 2 to 250,

[0129] - "a" is a number ranging from 0.05 to 0.95, "a" being the mole fraction of formula (I) units in the polymer,

[0130] - "b" is a number ranging from 0.05 to 0.95, "b" being the mole fraction of formula (II) units in the polymer,

[0131] - “L” represents a bonding group to the main chain of the polymer, and is in particular chosen from a direct bond (no atom between the main chain and the W group or the carbon bearing the R11 group), an oxygen atom, an -NR12- ​​group, R12 being a hydrogen or an alkyl group in C1 to C6, and an alkylene group in C1-C6, preferably L is an oxygen atom or an -NR12- ​​group, advantageously L is an oxygen atom,

[0132] - n = 0 or 1, and if n = 1, "W" is a spacer group, in particular an alkylene group in C1 to C20 preferably in C1-C6, possibly substituted, or a group of formula -[Al kyl-O] t - in which the "Alkyl" of each unit [Alkyl-O] independently represents an alkylene group comprising 2 to 4 carbon atoms, and "t" is an integer ranging from 1 to 500, preferably W is an alkylene group in C1 to C6,

[0133] - "R10" each independently represents a monovalent group, in particular chosen from a hydrogen, an alkyl group in C1 to C6, and a group of formula -[Alkyl- O] t -R13 in the "Alkyl" of each unit [Alkyl-O] independently represents an alkylene group of 2 to 4 carbon atoms, "t" is an integer ranging from 1 to 500 and "R13" is chosen from a hydrogen and an alkyl in C1 to C3, or "R10" is a cation, notably an alkali, alkaline earth or ammonium cation (and then the last O of the -[Alkyl-O] group t is O');

[0134] - "R11" is a monovalent group, in particular chosen from a hydrogen atom, a hydroxyl group and an alkyl group in C1 to C10, preferably "R11" is a hydroxyl group; and

[0135] - "c" is a number from 0 to 0.15, "c" being the mole fraction of formula (III) units in the polymer.

[0136] An atom or group of atoms defined as "representing independently" or "each representing independently" means that each of these atoms or groups of atoms can each be different from one unit of the polymer to another.

[0137] Preferably, polycarboxylate polyalkoxylated polymers have a comb-like structure.

[0138] Preferably, the polyalkoxylated phosphonate polymers have the following formula (IV): in which

[0139] - "R5" is a hydrogen atom or a monovalent hydrocarbon group comprising 1 to 18 carbon atoms and possibly one or more heteroatoms;

[0140] - the "Ri" are similar or different from each other and represent an alkylene such as ethylene, propylene, butylene, amylene, octylene or cyclohexene, or an arylene such as styrene or methylstyrene, the "Ri" possibly containing one or more heteroatoms;

[0141] - “Q” is a hydrocarbon group comprising 2 to 18 carbon atoms and possibly one or more heteroatoms;

[0142] - "A" is an alkylene group consisting of 1 to 5 carbon atoms;

[0143] - The "Rj" values ​​are similar or different from each other and can be chosen from:

[0144] - the group A-PO3H2, A having the aforementioned meaning,

[0145] - an alkyl group comprising from 1 to 18 carbon atoms and capable of bearing [R5-O(Ri-O)] groups m ], R5 and Ri having the aforementioned meanings, - "m" is a number greater than or equal to 0,

[0146] - "r" is the number of groups [R5-O(Ri-O) m supported by all the RJs,

[0147] - "q" is the number of groups [R5-O(Ri-O) m carried by Q, the sum

[0148] - "r+q" is between 1 and 10,

[0149] - "y" is an integer between 1 and 3,

[0150] - “Q”, “N” and the “Rj” can together form one or more rings, this or these rings may in addition contain one or more other heteroatoms.

[0151] Water reducing agents or high water reducing agents, other than polycarboxylate polyalkoxylated polymers and polyalkyloxylated phosphonate polymers, may also be used, possibly in combination with polycarboxylate polyalkoxylated polymers and polyalkyloxylated phosphonate polymers.

[0152] This includes, in particular:

[0153] - sulfonated salts of naphthalene and formaldehyde polycondensates, commonly called polynaphthalene sulfonates or naphthalene-based superplasticizers;

[0154] - sulfonated salts of melamine and formaldehyde polycondensates, commonly called polymelamine sulfonates or melamine-based superplasticizers;

[0155] - lignin derivatives such as lignosulfonate salts;

[0156] - sodium gluconate and sodium glucoheptonate;

[0157] - polyacrylates;

[0158] - polyarylethers (PAEs).

[0159] Preferably, these water-reducing or high-water-reducing agents are chosen from lignin derivatives such as lignosulfonate salts, sodium gluconate, and sodium glucoheptonate.

[0160] Preferably, the total mass content of water-reducing agent or high-strength water-reducing agent ranges from 0% to 5.0% by mass, preferably from 0.1% to 2.5% by mass, preferably from 0.2% to 1.7% by mass, and preferably from 0.3% to 1.0% by mass, relative to the dry mass of the hydraulic binder composition. If the water-reducing agent(s) or high-strength water-reducing agent(s) is / are added to the hydraulic composition, these contents therefore express the content of the water-reducing agent(s) or high-strength water-reducing agent relative to the dry mass of the hydraulic binder composition included in the hydraulic composition.

[0161] If several (at least two) water-reducing or highly water-reducing agents are present, the above concentration ranges refer to the total concentration of all water-reducing or highly water-reducing agents. Setting retardants

[0162] The term "setting retarder" refers to a compound that delays the setting of a hydraulic binder composition, meaning it delays or inhibits the phenomena associated with setting, such as hydration, thereby resulting in a later hardening of the hydraulic binder composition. Generally, a setting retarder delays the setting time of a hydraulic binder composition in which it has been introduced at a dosage of no more than 5% by dry mass relative to the mass of the clinker, with the setting time measured according to test EN 480-2:2006. Preferably, the setting time is delayed by at least 30 minutes compared to a control hydraulic binder composition.

[0163] The setting-delaying agent is chosen from among the following:

[0164] - a carboxylic or hydroxycarboxylic acid in neutral form or a salt thereof, those with a pK of 2 to 5 being preferred. The carboxylic acid being chosen in particular from acetic acid, gluconic acid, citric acid, tartaric acid, malic acid or a mixture thereof,

[0165] - a phosphonic acid in neutral form or a salt thereof, in particular chosen from those comprising a -N[-(CH2)-PO(OH)2]2 group or a >C[-PO(OH)2]2 group, preferably chosen from aminotrimethylenephosphonic acid (ATMP), ethylenediaminetetramethylenephosphonic acid (EDTMP), 1-hydroxyethylidene-1,1,-diphosphonic acid (HEDP), and their salts, in particular sodium salts.

[0166] - a sugar, in particular chosen from glucose, gluconic acid in neutral form or a salt thereof, or in lactone form, dextrose, fructose, galactose, sucrose, maltose, lactose and mannose and mixtures thereof,

[0167] - a phosphate, in particular selected from sodium tripolyphosphate and tetrapotassium pyrophosphate and mixtures thereof, and

[0168] - any one of their mixtures.

[0169] The salt of the carboxylic acid is preferably an alkali metal salt, such as sodium, lithium or potassium, an alkaline earth metal salt, such as a magnesium or calcium salt, or an ammonium salt (NH4). + or primary, secondary, tertiary or quaternary ammonium cation.

[0170] Antifoaming agents and / or air-entraining agents

[0171] Examples of antifoaming agents include ethoxylated fatty alcohols or amines, which modify the air entrainment provided by the additive composition in the hydraulic mixture. These antifoaming and / or air-entraining agents are preferably chosen from among the commonly used antifoaming and / or air-entraining agents known to those skilled in the art.

[0172] Biocidal agent

[0173] These molecules help protect the adjuvant composition from bacterial contamination over time. These biocidal agents are preferably chosen from among the commonly used biocidal agents known to those skilled in the art.

[0174] Rheological agent

[0175] Rheological agents are preferably compounds capable of increasing the yield stress of the paste of a hydraulic composition and / or the viscosity of the paste of a hydraulic composition.

[0176] Rheological agents are specifically chosen from:

[0177] - polysaccharide gums, for example diutan gums, xanthan gums, welan gums, guar gums and guar ethers, including hydroxyethyl guar, hydroxypropyl guar and carboxymethyl guar, gellan gums, starch and starch ethers,

[0178] - celluloses and cellulose ethers, including the alkyl, hydroxyalkyl and carboxyalkyl families,

[0179] - high molar mass polycarboxylates, preferably with a molar mass greater than 100,000 g / mol, preferably with a molar mass greater than 200,000 g / mol,

[0180] - polyethylene glycol (PEG) and polyethylene glycol monomethyl ether (MPEG), preferably with a molar mass greater than 100,000 g / mol,

[0181] - latexes, for example those of the methacrylic copolymer and ethyl acrylate ester type,

[0182] - polyacrylamides,

[0183] - polyvinyl alcohols,

[0184] - clays, for example sepiolite and bentonite type clays,

[0185] - sodium alginates, and

[0186] - any one of their mixtures.

[0187] Alkanolamine

[0188] If present, the alkanolamine(s) is / are preferably chosen from diethanolisopropanolamine (DEIPA), triisopropanolamine (TIPA), N,N-bis(2-hydroxypropyl)-N-(hydroxyethyl)amine (EDIPA), triethanolamine (TEA), N,N,N',N'-tetrakis(2-hydroxyethyl)ethylenediamine (THEED) and methyldiethanolamine (MDEA), bis-(2-hydroxypropyl)-amine (DI PA) and diethanolamine (DEA).

[0189] Adjuvant composition

[0190] In one embodiment, the wax is included in an adjuvant composition. In this embodiment, the adjuvant composition is used as a surface anti-dandruff adjuvant for a hydraulic composition or a hydraulic binder composition.

[0191] Preferably, according to this embodiment, the additive composition is added to the hydraulic binder composition or to the hydraulic composition in such an amount that the hydrocarbon mixture content of the wax ranges from 0.01% to 5.0% by mass, preferably from 0.02% to 2.0% by mass, preferably from 0.05% to 1.0%, preferably from 0.08% to 0.8% by mass, and preferably from 0.10% to 0.6% by mass, relative to the total dry mass of the hydraulic binder composition. When the additive composition is added to the hydraulic composition, the hydrocarbon mixture content of the wax is therefore expressed relative to the dry mass of the hydraulic binder composition included in the hydraulic composition.

[0192] Preferably, the adjuvant composition further includes at least one anti-shrinkage agent, as defined above.

[0193] Alternatively or in addition, the adjuvant composition further comprises at least one water-reducing agent or high water reducer selected from polyalkyl polycarboxylate polymers and polyalkyl phosphonate polymers, and any mixture thereof.

[0194] The adjuvant composition may also include any of the additional adjuvants listed below.

[0195] According to an alternative embodiment, the adjuvant composition and / or the hydraulic binder composition and / or the hydraulic composition is latex-free, in particular latex of the methacrylic copolymer type and ethyl acrylate ester.

[0196] The expressions "from ... to ...", "between ... and ...", "ranging from ... to ...", "varies from ... to ...", and "less than ..." should be understood inclusive of limits, unless otherwise specified.

[0197] The invention will become clearer upon reading the following examples, which are not exhaustive. EXAMPLES

[0198] Example 1: Effect of wax emulsions on the surface adhesion of a hydraulic composition screed

[0199] The following hydraulic composition Hy1 was prepared:

[0200] [Table 1]

[0201] The superplasticizer is a mixture of polyalkylated polycarboxylate polymers and polyalkylated phosphonate polymers in a ratio of 1:1.5.

[0202] The hydraulic composition was prepared according to the following protocol:

[0203] - 0 to 30 seconds: Mixing the sand at slow speed (tool speed: 140 rpm)

[0204] - At 30 seconds: Introduction of pre-wetting water, (1 / 3 of the added water) and mixing for 30 seconds.

[0205] - 1 min to 5 min: Rest for 4 minutes. The mixing bowl is covered with a lid to limit the evaporation of the pre-wetting water.

[0206] - At 5 min: Introduction of the binder (cement + mineral addition + additives).

[0207] Then the stopwatch is reset.

[0208] - 0 min to 1 min: One minute of mixing at slow speed (tool speed: 140 rpm)

[0209] - 1 min to 2 min: Introduction of the remaining water (2 / 3 added water) + addition of liquid adjuvants (superplasticizers, shrinkage reducing agent, wax emulsion, ...) during the mixing of the whole for 1 minute.

[0210] - 2 min to 2 min 30 sec: Stop mixing, scrape the sides and bottom of the bowl.

[0211] - 2min30s to 3min30s: Resumption of mixing for 1 minute at high speed (tool speed: 285 rpm).

[0212] Two wax emulsions (emulsion A and emulsion B) were added to this hydraulic composition Hy1. These emulsions have the following characteristics:

[0213] [Table 2]

[0214] Initial measurements of CEN cone spread (according to the protocol described in technical document DT 99046-01), fresh air content (according to the protocol described in technical document DT 99046-01) and surface adhesion measurements at 28 days according to DT 99046-1 were carried out.

[0215] In the case of the hydraulic composition without added wax emulsion, the slab surface was also sanded to allow for comparison with the hydraulic compositions containing a wax emulsion. The dosages used in wax emulsion (A and B) are expressed as a percentage of dry matter (active materials, including wax, surfactants, etc.) relative to the total binder quantity (cement + limestone filler). The results are summarized in the following table:

[0216] [Table 3] These results show that adding wax emulsions A and B allows for adhesion performance similar to that of the sanded composition, without sanding. Indeed, the surface adhesion of composition Hy1 without prior sanding is low (0.3 MPa), unlike the case where the surface is previously sanded, where the adhesion is 1.1 MPa.

[0217] Furthermore, the addition of wax emulsions A and B does not affect the initial spreading of the Hy1 composition and does not lead to a significant increase in the fresh air content of the hydraulic composition. The use of wax emulsions A and B has no adverse effect on the long-term mechanical behavior of the hydraulic composition (compressive and flexural strengths).

[0218] Example 2: Effect of coupling shrinkage-reducing adjuvant and surface anti-dandruff adjuvant

[0219] A second hydraulic composition Hy2, corresponding to the composition Hy1 of example 1 without the shrinkage reducing agent, was prepared.

[0220] [Table 4] of polyalkoxylated phosphonate polymers in a ratio of 1:1.5.

[0221] For both hydraulic compositions, a surface anti-film agent such as those described in FR 2948930 was added, along with wax emulsion A from Example 1. Surface adhesion measurements of the hydraulic compositions were performed in each case. The results are summarized in the following table:

[0222] [Table 5]

[0223]

[0224] The addition of wax emulsion A results in high surface adhesion performance of the hydraulic composition, regardless of whether the composition contains a shrinkage-reducing agent (Tests I and J). No incompatibility with the shrinkage agent is observed, whereas the shrinkage-reducing agent associated with the prior art surface anti-film exhibits incompatibility with the anti-shrinkage agent (Test H).

[0225] Example 3: Comparison of mass incorporation of wax emulsion versus surface application (spraying)

[0226] In order to evaluate the adhesion performance of a surface-applied wax emulsion, wax emulsion A from Example 1 was sprayed onto the surface of composition Hy1 at a dosage of 90 g / m². 2 In parallel, wax emulsion A was also tested by mass addition to the hydraulic composition during the mixing stage. The results obtained are presented in the following table:

[0227] [Table 6]

[0228] Surface adhesion is improved, whether the wax emulsion is added to the surface or in bulk.

[0229] Example 4: Adhesion performance of the wax emulsion for other hydraulic compositions. Two other hydraulic compositions, Hy3 and Hy4, were tested with and without the addition of wax emulsion A from Example 1. The hydraulic compositions evaluated are defined in the table below:

[0230] [Table 7] The superplasticizer is a mixture of polycarboxylate polyalkoxylated polymers and polyalkoxylated phosphonate polymers in a ratio of 1:1.5.

[0231] For these two hydraulic compositions, wax emulsion A was tested and the results are presented in the following table [Table 8]

[0232] These results show that adding wax improves surface adhesion regardless of the nature of the hydraulic composition.

Claims

DEMANDS 1. Use of a wax, as an anti-film surface adjuvant of a hydraulic composition or of a hydraulic binder composition.

2. Use according to claim 1, wherein the wax comprises a mixture of hydrocarbons, this hydrocarbon mixture comprising, relative to its total mass: - 20% to 50% by mass, preferably 20% to 40% by mass, of C20-C25 hydrocarbons, - 50% to 80% by mass, preferably 60% to 80% by mass, of C26-C35 hydrocarbons, and - from 0% to 5% by mass of hydrocarbons in C36 or higher.

3. Use according to claim 1 or 2, wherein the wax comprises a mixture of hydrocarbons in the form of particles having a D50 particle size between 0.8 and 2.0 pm and / or a D10 particle size strictly less than 1.0 pm, and / or a D90 particle size between 1.0 and 5.0 pm.

4. Use according to any one of the preceding claims, wherein the wax is in the form of an emulsion, preferably a direct or reverse emulsion.

5. Use according to any one of the preceding claims, including the addition of the wax to the mass of the hydraulic composition or to the surface of the hydraulic composition, preferably to the mass of the hydraulic composition.

6. Use according to any one of claims 1 to 4, including the addition of the wax to the hydraulic binder composition, before mixing.

7. Use according to any one of the preceding claims, wherein the wax comprises a mixture of hydrocarbons, and is added to the hydraulic binder composition or to the hydraulic composition in an amount corresponding to 0.01% to 5.0% by mass of the hydrocarbon mixture of the wax, preferably 0.02% to 2.0% by mass, preferably 0.05% to 1.0%, preferably 0.08% to 0.8% by mass, preferably 0.10% to 0.6% by mass, relative to the total dry mass of the hydraulic binder composition.

8. Use according to any one of the preceding claims, wherein the hydraulic composition has a mass ratio w / c greater than or equal to 0.

45.

9. Use according to any one of the preceding claims, wherein the wax is used in combination with at least one anti-shrinkage agent.

10. Use according to claim 9, wherein the anti-shrinkage agent is present in the hydraulic binder composition or the hydraulic composition and / or the anti-shrinkage agent is added to the hydraulic composition or to the hydraulic binder composition after the addition of the wax.

11. Use according to any one of the preceding claims, wherein the hydraulic composition and / or the hydraulic binder composition further comprises a water reducing agent or high water reducing agent selected from polyalkoxylated polycarboxylate polymers and polyalkoxylated phosphonate polymers, and any mixture thereof, and / or the use comprises the addition of a water reducing agent or high water reducing agent selected from polyalkoxylated polycarboxylate polymers and polyalkoxylated phosphonate polymers, and any mixture thereof, to the hydraulic composition or to the hydraulic binder composition after the addition of the wax.

12. Use according to any one of the preceding claims, wherein the wax is included in an adjuvant composition.

13. Use according to any one of the preceding claims, to reduce or even eliminate the appearance of a film on the surface of the hydraulic composition.

14. Use according to any one of the preceding claims, to improve, preferably by at least 30%, the surface adhesion of a cementitious material obtained from the hydraulic composition, and preferably from a self-placing screed.

15. Method for reducing, or even eliminating, the appearance of a surface film of a hydraulic composition, comprising the addition of a wax, in the mass or on the surface of a hydraulic composition, or in the hydraulic binder composition of the hydraulic composition.

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