Treatment for deactivating clays in hydraulic compositions used in the construction industry

Abstract

The present invention relates to a process for deactivating clay in hydraulic compositions intended for construction, comprising the step of adding to the hydraulic composition or one of its components a clay deactivator which is a water-soluble polymer consisting of at least one acrylamide and / or vinylamine and / or vinylformamide monomer unit and optionally monomer units of chemical nature different from those of the clay deactivator, characterized in that its weight average molecular weight is between Mw L and Mw H.

Description

[Technical field]

[0001] The present invention relates to a treatment for deactivating clay in an aqueous construction composition. [Background technology]

[0002] Cementitious aqueous compositions used on construction sites contain fine aggregates of various qualities, especially sand. This dilution sometimes requires resorting to rock crushing. Generally, fine aggregates contain a significant amount of clay. Some are swelling and can spread in a lateral slip, absorbing so much water on the outer and inner surfaces that the fine aggregates become hydrated, reducing the quality of the aggregate and causing large variations in the properties of the hydraulic composition. In the wet state, problems with rheological properties arise, and in the hardened state, they can cause safety problems, such as embrittlement of the structure.

[0003] Aqueous compositions are characterized by the water / aqueous binder ratio. The strength and durability of the finished cement depend on this ratio. The lower the water / aqueous binder ratio, the greater the strength and durability. Superplasticizers are therefore used to lower this ratio. However, the clay in the fine aggregates traps the water and superplasticizer, resulting in poor performance during installation and excessive admixture consumption. The variability caused by the clay in the fine aggregates makes it difficult to control the dosage of superplasticizer.

[0004] To circumvent these problems, synthetic polymers have been developed to deactivate clays. WO 98 / 58887 proposes the use of agents that modify the activity of clays to prevent the absorption of EO / PO type superplasticizers by the clays and thus improve the performance of cements and concretes. In particular, the use of inorganic or organic cation containing cationic polymers such as alkoxylated quaternary polyamines is proposed.

[0005] WO 2006 / 032785 proposes the use of cationic polymers having a charge density of more than 0.5 meq / g, in particular cationic polymers obtained by condensation of epichlorohydrin with dialkylamines.

[0006] WO 2013 / 124003 suggests the use of other cationic polymers such as polyamines functionalized with cationic groups.

[0007] The inert clay polymers described in the prior art are cationic and research has focused on polymers with high cationic properties to optimize performance, however these cationic polymers have many problems due to their quaternary ammonium functionality and high chloride content.

[0008] Chlorides damage cement-based foundations and affect their mechanical strength. In addition to the physical and chemical damage to these foundations, the risk of damage to engineered structures is increased by corrosion damage to metallic reinforcements.

[0009] Demineralization of rebar begins when chloride ions pass through the upper concrete and reach a critical concentration in the first layer of rebar. Currently, the critical concentration for concrete mixes around the world is standardized and based on scientific knowledge, observations and experience, it can sometimes be less than 0.2% chloride by mass of cement.

[0010] The phenomenon is very complex and causes serious problems for the durability and safety of constructions. For this reason, the industry has implemented standards such as NF EN 14629 for the measurement of chloride content in hardened concrete. This standard is primarily intended to estimate the risk of chloride corrosion of reinforcing steel.

[0011] For this reason, the construction industry is looking for solutions to reduce as much as possible the chloride concentration in hydraulic compositions.

[0012] WO 2018 / 054991 concerns a process for obtaining cationic high density polymers with reduced chloride content. The cationic polymers can be used in compositions based on mineral binders to inhibit clay. However, after this process the chloride content is still high and does not meet the standard requirements. This makes the existing solutions insufficient. [Prior art documents] [Patent documents]

[0013] [Patent Document 1] WO 98 / 58887 [Patent Document 2] International Publication No. 2006 / 032785 [Patent Document 3] International Publication No. 2013 / 124003 [Patent Document 4] International Publication No. 2018 / 054991 Summary of the Invention [Problem to be solved by the invention]

[0014] The present invention provides a clay deactivator that improves the performance of hydraulic compositions intended for construction applications and that is chloride-free. [Means for solving the problem]

[0015] The present invention is based on the observation that water-soluble polymers of specific chemical properties and specific molecular weights provide improved passivation performance of clay in aqueous construction compositions and are chloride-free, thereby meeting the standard requirements.

[0016] It is also based on the observation that the inactivation properties of clay are further improved when these water-soluble polymers contain a specific amount of hydrophobic monomer units.

[0017] The present invention makes it possible to achieve the environmental objectives inherent in new technological innovations, where improved polymer performance is expected to reduce the consumption of polymers.

[0018] Also, as indicated above, the polymers of the present invention are chloride-free, which not only results in stronger construction materials, but also allows a significant reduction in the water consumption and pollution normally associated with washing sand and fine aggregates on filter belts, thus saving this resource for more efficient use and avoiding the pollution of the environment with polluted water.

[0019] Also, because it does not contain chlorides, it can prevent salt damage from water, which sometimes leads to desertification.

[0020] Finally, the monomers used in the polymer have a smaller carbon footprint than those used in prior art polymers: they consist of just three carbons, the minimum for any functional polymer (except polyethylene), and they can be produced in a short time compared to petroleum.

[0021] This makes the polymer more favorable for the environment and its users, both in terms of its composition and its application advantages.

[0022] The present invention relates to a process for deactivating clay in hydraulic compositions intended for construction. The process comprises the step of adding to the hydraulic composition or one of its components a clay deactivator which is a water-soluble polymer ( ) consisting of at least one acrylamide and / or vinylamine and / or vinylformamide monomer unit and optionally monomer units of chemical nature different from those of the clay deactivator, characterized in that its weight average molecular weight is between Mw L and Mw H and its chemical nature is as follows: - Mw L=[AM] * 30+[VA] * 10+[VF] * 10+[MO] * 20. Also - MwH=[AM]* 500+[VA] * 3000+[VF] * 3000+[MO] * 2000, where [AM], [VA], [VF] and [MO] are the monomer percentages (mol%) relative to the total number of monomer units in the polymer, where the monomer units are acrylamide, vinylamine, vinylformamide and units of chemical nature different from the above chemical properties. The sum of [AM], [VA], [VF] and [MO] is equal to 100 mol%.

[0023] In a preferred embodiment, the polymer of the present invention is selected from: homopolymer of acrylamide, -Homopolyvinylamine -Homopolyvinylformamide - a copolymer consisting of two monomer units selected from acrylamide, vinylformamide, and vinylamine; - a terpolymer consisting of monomer units of acrylamide, vinylformamide and vinylamine, A terpolymer comprising at least two monomer units selected from acrylamide, vinylformamide, and vinylamine, and a monomer unit having at least hydrophobic properties.

[0024] In accordance with the present invention, the clay deactivator is a composition that includes at least two water-soluble polymers.

[0025] Water-soluble polymers according to the present invention are desirably non-ionic, that is, do not contain anionic or cationic charges.

[0026] In particular, it is essential that the water-soluble polymer according to the present invention does not contain chloride ions.

[0027] The present invention also relates to a hydraulic composition intended for construction purposes, comprising a fine aggregate according to the invention, at least one superplasticizer and at least one clay deactivator.

[0028] In the present invention, the term "water-soluble polymer" means a polymer which, when dissolved in water at 25° C. with stirring at a concentration of 20 g / L, forms an aqueous solution.

[0029] The term "polyacrylamide" refers to a polymer composed of acrylamide monomer units, "polyvinylamine" refers to a polymer composed of vinylamine monomer units, and "polyvinylformamide" refers to a polymer composed of vinylformamide monomer units. "Polyvinylformamide" refers to a polymer containing vinylamine monomer units.

[0030] "Superplasticizer" refers to a water-reducing polymer, i.e., a polymer that maintains high fluidity over time and high slump in hydraulic compositions. Chemically, these superplasticizers are carbon chain polymers, such as polycarboxylates, with oxyalkylated side chains, such as ethoxy or propoxy.

[0031] "Nonionic polymer" refers to a polymer that does not have any cationic or anionic charges on the polymer chain.

[0032] "Hydraulic composition" defines a hydraulically setting composition, in particular mortar, concrete and cementitious compositions for the construction industry.

[0033] By "one of its components", when this expression refers to a hydraulic composition, is meant the conventional components of hydraulic compositions known to those skilled in the art, such as fine aggregates (sand, limestone, etc.), superplasticizers, and cementitious binders, e.g., mortar or concrete, and also includes hydraulic binders, such as superplasticizers, and cementitious binders, e.g., mortar or concrete.

[0034] "Fine aggregate" refers to fine aggregates of different particle sizes, such as sand and gravel. The fine aggregates may be of mineral nature, such as calcareous, siliceous, siliceous, etc. In particular, fine aggregates such as sand as described in the context of the present invention include clays.

[0035] "Clay" refers to silicates of aluminum and / or magnesium, especially phyllosilicates having a layered structure typically spaced about 7 to about 14 angstroms apart. However, the term also includes other types of clays, especially amorphous clays. Clays that are abundant in aggregates include montmorillonite, illite, kaolinite, and muscovite.

[0036] The proportion of acrylamide and / or vinylamine and / or vinylformamide monomer units in the water-soluble polymer according to the invention is at least 70 mol %, preferably at least 80 mol %, more preferably 90 mol %, and preferably 95 mol % based on the total monomer units of the polymer. In addition to acrylamide, vinylformamide and vinylamine monomer units, the polymer according to the invention may contain monomer units of a different chemical nature than those mentioned above. By "chemical nature" we mean acrylamide, vinylformamide and vinylamine. These monomer units of a different chemical nature are hydrophobic monomer units, cationic monomer units, anionic monomer units or zwitterionic monomer units, preferably hydrophobic monomer units.

[0037] The polymer according to the invention preferably consists exclusively of acrylamide and / or vinylamine and / or vinylformamide monomer units, and optionally contains hydrophobic monomer units.

[0038] The water soluble polymer is preferably selected from acrylamide homopolymers, homopolyvinylamines and homopolyvinylformamides, with homopolyvinylamines and homopolyvinylformamides being preferred.

[0039] The acrylamide / vinylamine copolymers preferably contain only acrylamide and vinylamine monomer units. The acrylamide / vinylformamide copolymers preferably contain only acrylamide and vinylformamide monomer units. The vinylamine / vinylformamide copolymers preferably contain only vinylamine / vinylformamide monomer units. The acrylamide / vinylamine / vinylformamide terpolymers preferably contain only acrylamide, vinylamine and vinylformamide monomer units. The polymers according to the invention also preferably contain hydrophobic monomer units.

[0040] The proportion of acrylamide, vinylamine and / or vinylamide monomer units can be adjusted.

[0041] The polymer according to the invention preferably contains 0.001 to 20 mol % of hydrophobic monomer units, preferably 0.1 to 15 mol %, and more preferably 0.1 to 10 mol %. The monomers with hydrophobic properties are selected from the group consisting of esters of (meth)acrylic acid with alkyl, hydroxyalkyl, arylalkyl, propoxylated, ethoxylated, ethoxylated, or ethoxylated and propoxylated; (meth)acrylamide derivatives with alkyl, hydroxyalkyl, arylalkyl, propoxylated, ethoxylated, ethoxylated and propoxylated, or dialkyl chains; alkylarylsulfonates. Possibly hydroxyethyl acrylate, ethylhexyl acrylate, hydroxypropyl acrylate, butyl acrylate, propyl acrylate, dimethylacrylamide, butylacrylamide and tertbutylacrylamide.

[0042] The presence of hydrophobic monomers in the polymers according to the invention allows a wider range of dosages to improve performance, making the clay deactivator more flexible for use at the processing site, whether at the quarry for fine aggregates or at the site of the manufacture of hydraulic compositions, allowing specialists to adjust the dosage to obtain optimal performance.

[0043] Mannich products obtained by reacting a polymer consisting of acrylamide monomer units with formaldehyde and dimethylamine are also polymers of the present invention. Usually, these polymers do not contain chloride ions. These products can be protonated by adding a non-chlorine alkylating agent, possibly diethyl sulfate. The molecular weight of the Mannich products according to the present invention is between Mw L and Mw H.

[0044] Throughout this invention, it is understood that the mole percentage of polymer monomers equals 100%.

[0045] As already mentioned, the polymers according to the invention should preferably contain no cationic or anionic charges at the use pH of the product, which is generally between 10 and 13, and preferably no cationic, anionic or zwitterionic monomer units.

[0046] The weight average molecular weight of the polymers according to the invention, expressed in Daltons, is between Mw L and Mw H and is as follows: Mw L = 1.0; - Mw L=[AM] * 30+[VA] * 10+[VF] * 10+[MO] * 20. Also - MwH=[AM] * 500+[VA] * 3000+[VF] * 3000+[MO] * 2000, Here, [AM], [VA], [VF] and [MO] respectively represent the proportions of acrylamide, vinylamine and vinylformamide monomer units different from the above chemical properties relative to the total number of monomer units in the polymer, expressed in mol%.

[0047] The weight average molecular weight of the polymer according to the invention lies in the range [MwL-MwH], MwL consisting of the lower value of the range and MwH consisting of the upper value of the range.

[0048] When a polymer is composed of multiple types of monomer units with different chemical properties, such as acrylamide, vinylamine, or vinylformamide monomer units, the monomer fraction [MO] is equal to the sum of the fractions of these monomer units with different chemical properties.

[0049] When a polymer is composed of, for example, 90 mol % acrylamide monomer units, 5 mol % butyl acrylate monomer units, and 5 mol % dimethylacrylamide monomer units, then [MO] is equal to 10 mol %, Mw L is equal to 2900 Daltons, and Mw H is equal to 65000 Daltons.

[0050] When the water-soluble polymer according to the present invention is composed of at least 80 mol % acrylamide monomer units, its weight average molecular weight is preferably 2.5 * Mw L and 0.8 * Mw H, plus 3.3 * Mw L and 0.6 * Mw L - Mw H, and these preferred ranges therefore constitute a more restricted range of weight average molecular weight than the aforementioned [Mw L - Mw H] range. When the polymer according to the invention is an acrylamide homopolymer, its weight average molecular weight is preferably between 7500 and 40000 Daltons, or even between 10000 and 30000 Daltons.

[0051] When the water-soluble polymer according to the invention is composed of at least 80 mol % vinyl amide and / or vinyl formamide monomer units, its weight average molecular weight is preferably 2 * Mw L and 5 / 6 * Mw H, plus 5 * Mw L and 2 / 3 * Mw L - Mw H, and these preferred ranges therefore constitute a more restricted range of weight average molecular weight than the aforementioned [Mw L - Mw H] range. When the polymer according to the invention is a homopolyvinylamide or homopolyvinylformamide, its preferred weight average molecular weight is preferably 7,500 to 40,000 Daltons, and even 10,000 to 30,000 Daltons.

[0052] According to the invention, the polymers have a linear, branched, star, comb, dendritic or block structure. The polymers are linear or structured, preferably linear. Structured polymers are non-linear polymers with side chains.

[0053] In general, the polymers do not require the development of a specific polymerization process and can be obtained using any polymerization technique well known to those skilled in the art, such as solution polymerization, gel polymerization, precipitation polymerization, emulsion polymerization (aqueous or inverse), suspension polymerization, reactive extrusion polymerization, underwater polymerization, micellar polymerization, etc.

[0054] The polymerization is generally free radical, preferably solution, and can include free radical polymerization using UV, azo, redox, or thermal initiators, as well as controlled radical polymerization (CRP) or matrix polymerization techniques.

[0055] A particularly advantageous technique for preparing the polymers of the invention is RAFT (Reversible Addition-Fragmentation Chain Transfer) polymerization, which allows the synthesis of low-dispersity, highly functional polymers with controlled architectures (block, star, comb, etc.).

[0056] Polyvinylamine can be obtained as follows: - Hoffmann degradation of (co)polymers containing at least one nonionic monomer selected from the group consisting of acrylamide, methacrylamide, N,N-dimethylacrylamide, t-butylacrylamide, octylacrylamide, and / or (but not limited to) - the (co)polymerization reaction of at least one monomer of formula (I): [ka] wherein R1 and R2 are each independently a hydrogen atom or an alkyl chain having 1 to 6 carbon atoms; Some or all of the -CO-R1 groups are then removed, for example by hydrolysis, to form amine functions.

[0057] Examples of monomers of formula (I) include N-vinylformamide, N-vinyl-N-methylformamide, N-vinylacetamide, N-vinyl-N-methylacetamide, N-vinyl-N-ethylacetamide, N-vinylpropianamide, N-vinyl-N-methylpropianamide, N-vinylbutyramide, etc. Desirably, the monomer is N-vinylformamide.

[0058] These monomers of formula (I) can be used alone or copolymerized with other monomers in the broad sense, such as acrylamide or hydrophobic monomers, provided that the latter are not sensitive to hydrolysis.

[0059] The polyvinylamine is preferably obtained by a hydrolysis reaction (preferably basic) of polyvinylformamide, the polyvinylformamides being obtainable by methods known to the specialist.

[0060] For the measurement of the weight average molecular weight, gel permeation chromatography (GPC) is used. The weight average molecular weight is measured, for example, on an Agilent 1260 Infinity system equipped with a Dawn HELOS, OPtilab T-Rex multi-angle light scattering detector and two columns in series: Shodex SB 807-HQ et Shodex 805-HQ. The mixture is diluted to 1000 ppm with a saline mobile phase and filtered at 1.2 μm. The direct measurement of polyvinylamine is complicated, and its molecular weight is determined by the same instrumental system for the desired polyacrylamide or poly(N-vinylformamide) precursors, assuming that the conversion to polyvinylamine is quantitative, i.e. the reaction is complete.

[0061] The polymeric clay deactivator can be used in different forms, preferably in the form of an aqueous solution containing 1-50% by weight of the deactivator, which is added by pouring or spraying into the hydraulic composition or one of its components.

[0062] The hydraulic composition preferably comprises a cementitious binder. It is preferably a mortar or concrete. It preferably comprises 20-90% by weight of fine aggregate and 0.01-1% by weight of a superplasticizer, based on the dry basis of the composition. The other components of the hydraulic composition are those usually found in the manufacture of said compositions. The method of preparation of the liquid composition is carried out according to the knowledge of the specialist.

[0063] When the deactivator according to the invention is added to the hydraulic composition, it can be added at any stage during the preparation of the composition, which is convenient to use and does not cause mixing problems.

[0064] If the deactivator according to the invention is added to one of its components, this addition is carried out before the addition of this component to the hydraulic composition, for example, the deactivator can be added to the fine aggregate intended for the preparation of the hydraulic composition.

[0065] In this case, the fine aggregate is brought into contact with the inert agent, if possible by mixing during or after processing, to ensure good dispersion of the composition and to obtain a homogeneously processed material. Fine aggregates with a clay content of 0.1-2% by weight are generally processed. The fine aggregate should, if possible, be dry (water content not more than 10% by weight) at the time of processing. The fine aggregate is preferably processed in the quarry.

[0066] In principle, any contact of the deactivating agent with the fine aggregate is sufficient to ensure the deactivation of the clay contained in the fine aggregate. Contact for a few seconds to a few minutes is generally sufficient.

[0067] The deactivator is desirably used in an appropriate amount to ensure complete deactivation of the fine aggregate or clay present in the hydraulic composition.

[0068] As a guideline, a dose of 2-200 ppm of deactivator based on the weight of fine aggregate is generally sufficient to treat the fine aggregate. Professionals can adjust the dose to obtain optimal performance.

[0069] As mentioned above, the addition of a passivating agent improves clay inhibition, produces a chloride-free solution that meets code requirements and market expectations, and in the long term reduces corrosion of metals and attack of the cementitious matrix, improving the durability of structures. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0070] The following examples are merely illustrative for the purposes of the present invention and are not intended to be limiting in any way.

[0071] [Example] 1. Clay deactivation polymer The polymers described in the examples are chloride-free. In the following the process for obtaining the polymers is described.

[0072] The acrylamide homopolymer is obtained by a solution polymerization process in deionized water. The amount of transfer agent is adjusted to give the molar mass given in Table 1.

[0073] Homopolyvinylamine is obtained by polymerization of poly(N-vinylformamide) in aqueous solution followed by alkaline hydrolysis. The hydrolysis is quantitative.

[0074] Acrylamide / vinylamine copolymers can be obtained by Hoffmann degradation of polyacrylamide in the presence of sodium hypobromite, followed by casting of the polyisocyanate with an excess of acid.

[0075] The copolymer of acrylamide and N-vinylformamide can be obtained by copolymerizing acrylamide and N-vinylformamide in deionized water by a solution polymerization method.

[0076] Terpolymers of acrylamide, vinylamine and N-vinylformamide can be obtained by the Hoffmann degradation of copolymers of acrylamide and N-vinylformamide as described above.

[0077] Table 1 below summarizes the compositions of the polymers synthesized.

[0078] [Table 1]

[0079] ACM: Acrylamide VA: Vinylamine EPI / DMA: A cationic polymer obtained by polycondensation of epichloridrin and dimethylacrylamide. DMA: Dimethylacrylamide VF: Vinyl formamide BA: Butyl acrylate Mw: Weight average molecular weight The polymer of Example 3 contains 26% chloride by weight.

[0080] 2 / Application test Portland Le Classique cement (Lafarge, CEM II-32.5 R, Cimenterie Le Teil), standard sand (Societe Nouvelle du Littoral) and clay (bara-kade 200, Bentonite Performance Minerals LLC) are added to the mixer bowl and mixed at low speed for 15 seconds to homogenize. An aqueous solution of superplasticizer (Floset SH5) and clay inertizer is prepared and added to the cement mixture over 30 seconds, stirring at low speed. The dough is then mixed for another 5 minutes. The water / cement ratio is 0.45. The superplasticizer mass is 0.5% by weight of cement. The sand / cement ratio is equal to 3. The amount of inerts depends on the test product and is expressed as the ratio of dry product to sand.

[0081] The paste is then poured into an inverted cone (Abrams cone) on a Plexiglas plate. When the cone is lifted, the batter spreads out. The diameter (D) of the wafer is measured.

[0082] Applying the following formula, compare the diameter of the cake without clay (Dmax = 320 mm) to the diameter of the cake without inert agent (Dmin = 250 mm): Diffusion ratio = (D-Dmin) / (Dmax-Dmin) x 100

[0083] The closer the value is to 100%, the greater the inhibitory effect of the clay.

[0084] Previously synthesized inert clay polymers were tested. For each example, the point at which performance was optimal was determined. The results are shown in Table 2 below.

[0085] [Table 2]

[0086] The inactive clay polymer of the invention performed better than the control examples. The recovery rate without the use of an inactive agent was at least 50%. For the other polymers, it was less than 50%. Furthermore, the polymer of the invention is more effective and the dosage can be significantly reduced. Polyvinylamine showed excellent results with a spread of more than 60% at a dosage of 20 ppm or less. Polyvinylformamide also showed excellent performance with a spread recovery rate of 100%. Finally, it is noted that the cationic polymer of the control example 3 containing chlorides (26% by weight) performed worse than the polymer according to the invention without them.

[0087] 3 / Tests for copolymers containing hydrophobic monomers The polymer of Example 4 was compared with the polymers of Examples 10 and 12. A second similar application test was carried out. The loading of the polymer was varied and the performance was as shown in Table 3.

[0088] [Table 3]

[0089] The inert clay polymers of the present invention containing hydrophobic monomers (Ex10 and 12) provide good performance over a wider dosage range, allowing for greater flexibility in their use at the processing site, whether at the quarry for fine aggregates or at the manufacturing site for hydraulic compositions.

Claims

1. 1. A method for deactivating clay in a hydraulic composition intended for construction, said method comprising the step of adding at least one clay deactivator to the hydraulic composition or one of its components, characterized in that the clay deactivator is a chloride-free, water-soluble polymer comprising acrylamide and / or vinylamine and / or vinylformamide monomer units and, optionally, monomer units of a chemical nature different from those of the clay deactivator, and whose weight-average molecular weight is between Mw L and Mw H, Mw L = [AM] ＊ 30+ [VA] ＊ 10+[VF] ＊ 10+ [MO] ＊ 20. Also Mw H=[AM] ＊ 500+[VA] ＊ 3000+[VF] ＊ 3000+[MO] ＊ 2000、 wherein [AM], [VA], [VF] and [MO] are each the proportion (mol %) of monomers relative to the total number of monomer units of the polymer, the monomer units being acrylamide, vinylamine, vinylformamide and units of chemical nature different from the above-mentioned chemical nature, the sum of [AM], [VA], [VF] and [MO] being equal to 100 mol %, and the proportion of acrylamide, and / or vinylamine, and / or vinylformamide monomer units in the water-soluble polymer is preferably at least 70 mol % relative to the total monomer units of the polymer.

2. 2. The method of claim 1, wherein the water-soluble polymer is non-ionic.

3. The water-soluble polymer may be one of the following: - acrylamide homopolymer, homopolyvinylamine, - homopolyvinylformamide, - copolymers comprising two monomer units selected from acrylamide, vinylformamide and vinylamine; - terpolymers containing acrylamide, vinylformamide and vinylamine monomer units, a terpolymer comprising at least two monomer units selected from acrylamide, vinylformamide, and vinylamine and at least one hydrophobic monomer unit; 3. The method according to claim 1 or 2, characterized in that the compound is selected from the group consisting of:

4. 3. The method according to claim 1 or 2, characterized in that the water-soluble polymer comprises only acrylamide and / or vinylamine and / or vinylformamide monomer units, and optionally hydrophobic monomer units.

5. 3. The method according to claim 1, wherein the water-soluble polymer is selected from acrylamide homopolymer, homopolyvinylamine and homopolyvinylformamide.

6. 3. The method of claim 1, wherein the water-soluble polymer comprises hydrophobic monomer units.

7. 3. The method according to claim 1, wherein the water-soluble polymer contains 0.001 to 20 mol % of hydrophobic monomer units.

8. 7. The method according to claim 6, wherein the hydrophobic monomer is hydroxyethyl acrylate, hydroxypropyl acrylate, butyl acrylate, propyl acrylate, dimethylacrylamide, butylacrylamide.

9. The water-soluble polymer contains at least 80 mol % acrylamide monomer units, and ＊ Mw L and 0.8 ＊ 3. The method according to claim 1 or 2, characterized in that the polymer has a weight average molecular weight between Mw H.

10. The water-soluble polymer contains at least 80 mol % vinylamide and / or vinylformamide monomer units, ＊ MW L to 5 / 6 ＊ 3. The method according to claim 1 or 2, characterized in that the polymer has a weight average molecular weight between Mw H.

11. 3. The method of claim 2, wherein the nonionic water-soluble polymer is linear.

12. 3. The method according to claim 1 or 2, characterized in that the water-soluble polymer is added to the hydraulic composition or one of its components in a dosage of 2 to 200 ppm of inert agent relative to the weight of the fine aggregate.

13. A hydraulic construction composition comprising a fine aggregate, said fine aggregate comprising clay, at least one superplasticizer, and at least one clay deactivator, characterized in that said clay deactivator is a chloride-free, water-soluble polymer comprising acrylamide and / or vinylamine and / or vinylformamide monomer units, and optionally monomer units of a chemical nature different from said chemical nature, and whose weight average molecular weight is between MwL and MwH; Mw L = [AM] ＊ 30+ [VA] ＊ 10+[VF] ＊ 10+ [MO] ＊ 20. Also Mw H=[AM] ＊ 500+[VA] ＊ 3000+[VF] ＊ 3000+[MO] ＊ 2000、 wherein [AM], [VA], [VF] and [MO] are the monomer proportions (mol %) relative to the total number of monomer units of the polymer, the monomer units being acrylamide, vinylamine, vinylformamide and units of chemical nature different from the above-mentioned chemical nature, the sum of [AM], [VA], [VF] and [MO] being equal to 100 mol %, and the proportion of acrylamide, and / or vinylamine, and / or vinylformamide monomer units in the water-soluble polymer is, if possible, at least 70 mol % relative to the total monomer units of the polymer.

14. 14. The composition of claim 13, wherein the composition is a mortar or concrete.