STABLE AMINE-BASED DEFOAMERS FOR ADDITIVES

Abstract

A defoamer for reducing air entrapment in cement compositions. The defoamer is a polyalkoxylated alkylpolyamine having the structure of formula (1) or (2) and salts thereof, R 1 -(N(R 2 )-CH2-CH2-CH2) n -N-(R 3 )(R 4 ) (1), R 1 -N(CH2-CH2-CH2-N(R 3 )(R 4) )2 (2), where R 1 is a branched or unbranched hydrocarbon chain having a length of 1 to 20 carbons, R 2 , R 3 and R 4 each independently represents at least one or more of H, an alkylene oxide, or a polyalkylene oxide, and n is 1 to 50. The defoamer can be used with a superplasticizer in an admixture for a cement composition. The defoamer provides increased stability and solubility of the admixture under thermal aging.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application is based on U.S. Application No. 63 / 374,839, filed September 7, 2022. The contents of that application are incorporated herein by reference in their entirety. BACKGROUND OF THE INVENTION TECHNICAL FIELD

[0002] The present invention relates to an alkoxylated alkylpolyamine defoamer for controlling air entrapment in cementitious compositions. DESCRIPTION OF THE RELATED ART

[0003] The "Background" description provided herein is intended to provide a general context for the disclosure. The work of the present inventors, to the extent described in this Background section, as well as aspects of the description that might not otherwise constitute prior art at the time of filing, are not expressly or by implication admitted as prior art to the present invention.

[0004] Concrete production requires the mixing of several components such as hydratable cement, sand, gravel, water, and additives to form a homogeneous mixture. A commonly used additive is a superplasticizer, which is incorporated into the mix to reduce the required water content, optimize initial flow and slump retention over time, and improve mechanical properties such as compressive strength. Furthermore, an admixture for controlled air entrainment is desirable to impart increased freeze-thaw stability to the set concrete. Superplasticizers often have comb-like copolymer structures, with one monomer comprising carboxylate end groups and another monomer comprising ethylene oxide repeat units bound to the polymer chain. In particular, comb-like copolymers derived from acrylic acid monomers are well-known superplasticizers.

[0005] An undesirable side effect of superplasticizers is the introduction of excess air into the finished concrete. This air entrapment can have a positive effect on the freeze-thaw stability of the concrete, but precise control of air entrapment is required to prevent an undesirable negative impact on the physical properties (compressive strength) of the set concrete. The standard approach to reducing such a negative impact is the use of defoamers to minimize air entrapment. Such defoamers are generally hydrophobic materials such as non-ionic surfactants with a low HLB, silicone derivatives, di- and tri-butyl phosphates, and alkyl phthalates.

[0006] Due to the hydrophobic nature of defoamers, they are poorly water-soluble and cannot be incorporated into aqueous admixture solutions with long-term stability. Attempts to make the defoamers compatible in miscible polymers or by dispersion in the admixture (especially superplasticizer) solution do not result in extended stability. Rapid phase separation typically occurs in blended mixtures, requiring separate storage of the aqueous superplasticizer solution and the defoamer and mixing only immediately before use to ensure good control of air entrapment. Alternatively, the defoamer can be added to a constantly stirred superplasticizer solution to prevent separation, sometimes with stabilizing surfactants; see U.S. Pat. No. 6,139,623, which is incorporated herein by reference in its entirety.Defoamer incompatibility in aqueous solvent solutions represents an obvious disadvantage for the user due to additional costs, space requirements and usage limitations.

[0007] State-of-the-art methods for overcoming the hydrophobic incompatibility problems of defoamers have been established. The incorporation of amine moieties into the defoamer structure can impart ionic pairing with carboxylic acid functionalities of the flow agent polymer structure. Kuo disclosed polyalkoxylated polyalkylenepolyamines as defoamers in US Pat. No. 8,187,376.

[0008] Like conventional defoamers, amine defoamers can only be used at relatively low concentrations in superplasticizer solutions to solve air entrapment problems. At higher concentrations, performance is reduced, and the admixture formulations typically become unstable after a short period of time. In particular, exposure of these solutions to elevated temperatures results in the separation of the defoamer from the aqueous superplasticizer solution. There is therefore still a need for a single, storage-stable cement admixture that can be used at low and high concentrations and maintains stability over a wide range of environmental conditions. In view of the foregoing, it is an object of the present invention to provide a defoamer with improved stability and the use of the defoamer in an admixture with a superplasticizer for cement compositions. BRIEF SUMMARY OF THE INVENTION

[0009] The present invention provides: (1) A defoamer for reducing air entrapment comprising a polyalkoxylated alkylpolyamine having a structure represented by the following formula (1) or (2) and salts thereof R 1 - (N(R 2 )-CH2-CH2-CH2) n -N-(R 3 )(R 4 ) (1), R 1 -N (CH2-CH2-CH2-N (R 3 ) (R 4 )) 2 (2), where R 1 is a branched or unbranched hydrocarbon chain having a length of 1 to 20 carbons, R 2 , R 3 and R 4 each independently represents H, an alkylene oxide or a polyalkylene oxide and n is 1 to 50. (2) A defoamer for reducing air entrapment comprising a polyalkoxylated alkyldiamine having a structure represented by formula (3) and salts thereof R 1 -N (R 2 ) -CH2-CH2-CH2-N-(R 3 ) 2 (3), where R 1 is a branched or unbranched hydrocarbon chain having a length of 1 to 20 carbons, R 2 and R 3 each independently represents H, an alkylene oxide or a polyalkylene oxide. (3) The defoamer according to (1) or (2), wherein the alkylene oxide is propylene oxide or ethylene oxide. (4) The defoamer according to any one of (1) to (3), wherein the alkylene oxide comprises repeating groups of propylene oxide and / or ethylene oxide. (5) The defoamer according to any one of (1) to (4), wherein R 1 a branched or unbranched hydrocarbon chain with a length of 12 to 18 carbons. (6) The defoamer according to any one of (1) to (5), wherein a combined weight percentage of propylene oxide and polypropylene oxide is in a range of 45 to 75 wt% relative to the polyalkoxylated alkylpolyamine. (7) The defoamer according to any one of (1) to (6), wherein R 1 a tallow alkyl (8) An additive comprising: the defoamer according to any one of (1) to (7) and an alkaline solution, suspension or slurry. (9) An additive for reducing air entrapment, comprising: a dispersant, the defoamer according to any one of (1) to (7), and water. The dispersant and defoamer are present in a combined concentration ranging from 25 to 35 wt% relative to the total weight of the additive, and the defoamer is present in a concentration of 0.1 to 20 wt% relative to the weight of the dispersant. (10) The additive according to (9), wherein the defoamer is present in a concentration of 4 to 15 wt.% relative to the total weight of the dispersant. (11) The additive according to (9) or (10), which has a pH in a range of 4.5 to 6.5. (12) The additive according to any one of (9) to (11), wherein the dispersant is a flow agent selected from the group consisting of a polycarboxylate ether, a sulfomodified melamine formaldehyde condensate, a melamine formaldehyde condensate, a sulfonated melamine formaldehyde condensate, a lignin salt, a naphthalenesulfonate, a polycarboxylated acrylic, a polycarboxylated ether, a carboxylic acid salt, casein, a cocomide derivative, and mixtures thereof. (13) The additive according to any one of (9) to (12), wherein the dispersant is at least one selected from the group consisting of a polycarboxylate ether, an ester type dispersant, an ether type dispersant, and a naphthalene type dispersant. (14) The additive according to any one of (9) to (13), wherein the dispersant is a polycarboxylate ether comprising pendant polyethylene oxide groups. (15) The additive comprising: a dispersant, the defoamer according to one of (1) to (7) and Water, wherein the dispersant and the defoamer are present in a combined concentration in a range of 25 to 35 wt.% relative to the total weight of the additive, and wherein the defoamer is present in a concentration of 0.1 to 20 wt.% relative to the weight of the dispersant, wherein the dispersant is a polycarboxylate ether copolymer including a constituent unit (4) represented by the following formula (4) and a constituent unit (5) represented by the following formula (5), where unit (4) is methylacrylic acid and its salt, where unit (5) is methoxypolyethylene glycol monomethacrylate, where n1 is an average number of moles added and represents a number of 15 or more and 30 or less, wherein a proportion of the constituent unit (4) in a total content of the constituent units (4) to (5) is 65 mol% or more and 80 mol% or less, and wherein a weight average molecular weight (Mw) of the polycarboxylate ether copolymer is 35,000 or more and 60,000 or less. (16) The additive comprising: a dispersant, the defoamer according to one of (1) to (7) and Water, wherein the dispersant and the defoamer are present in a combined concentration in a range of 25 to 35 wt.% relative to the total weight of the additive, and wherein the defoamer is present in a concentration of 0.1 to 20 wt.% relative to the weight of the dispersant. wherein the dispersant is a polycarboxylate ether copolymer including the constituent unit (4') represented by the following formula (4') and the constituent unit (5') represented by the following formula (5'), where unit (4') is methylacrylic acid and its salt, where unit (5') is methoxypolyethylene glycol monomethacrylate, where n1 is an average number of moles added and represents a number of 80 or more and 120 or less, wherein a proportion of the constituent unit (4') in a total content of the constituent units (4') to (5') is 70 mol% or more and 90 mol% or less, and wherein a weight average molecular weight (Mw) of the polycarboxylate ether copolymer is 35,000 or more and 60,000 or less. (17) A cement mixture comprising a particulate cementitious component, the admixture according to any one of (9) to (16) and water, wherein the admixture is present in the cement mixture at a concentration in a range of 0.05 to 1 wt% based on the weight of the cement. (18) The cement mixture according to (17), wherein the admixture is present in the cement mixture in a concentration in a range of 0.1 to 0.5 wt% based on the weight of the cement. (19) The cement mixture according to (17) or (18), which has a W / C ratio of 0.37 to 0.50. (20) The cement mixture comprising: a particulate cementitious component, an additive according to any one of (9) to (16) and Water, wherein a solids content of the admixture is present in the cement mixture in a concentration in a range of 0.05 to 1 wt.%, based on the weight of the cement, and where a W / C ratio is in a range of 0.37 to 0.50. (21) The cement mixture according to any one of (17) to (20), further comprising 45-60 wt% of sand relative to the total weight of the cement mixture. (22) A method for forming an additive, the method comprising mixing an alkaline aqueous solution, suspension or slurry and the defoamer according to any one of (1) to (7). (23) A method for forming a cement mixture, the method comprising mixing a particulate cementitious component, the admixture according to any one of (9) to (16), and water. The admixture is present in the cement mixture at a concentration in a range of 0.05 to 1 wt% based on the weight of the cement. (24) The process for forming a cement mixture, the process comprising: Mixing a particulate cementitious component, of the additive according to one of (9) to (16) and Water, wherein the admixture is present in the cement mixture in a concentration in a range of 0.05 to 1 wt.%, based on the weight of the cement and where a W / C ratio is in a range of 0.37 to 0.50. (25) A method for reducing air voids in a cement mixture, the method comprising: Mixing the defoamer according to any one of (1) to (7) and a dispersant with a cement mixture. (26) Use for a defoamer of a composition comprising a polyalkoxylated alkylpolyamine having a structure represented by formula (1) or (2) and salts thereof R 1 -(N(R 2 ) -CH2-CH2-CH2) n -N- (R 3 ) (R 4 ) (1), R 1 -N (CH2-CH2-CH2-N (R 3 ) (R 4 )) 2 (2), where R 1is a branched or unbranched hydrocarbon chain having a length of 1 to 20 carbons, R 2 , R 3 and R 4 each independently represents H, an alkylene oxide or a polyalkylene oxide and n is 1 to 50. (27) Use for a defoamer of embodiment (23) for an alkaline aqueous solution, suspension or slurry. (28) Use for a defoamer of embodiment (23) for a hydraulic composition.

[0010] The preceding paragraphs are intended merely as a general introduction and are not intended to limit the scope of the following claims. The described embodiments, as well as other advantages, will best be understood by reference to the following detailed description taken in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] A full appreciation of the disclosure and many of its attendant advantages will be readily achieved as the same becomes better understood by reference to the following detailed description taken in conjunction with the accompanying drawings, in which: Fig. 1A shows the control superplasticizer M-1 without defoamer. Fig. Figure 1B shows the superplasticizer M-1 as it is and premixed with an ester defoamer (0.50 wt% defoamer loading / active PCE) after 1 week of thermal aging at 50°C. Fig. Figure 2 shows the long-term stability of different defoamer S2 loadings (0.5 to 12.0% per active PCE) in the superplasticizer M-2 after thermal aging. Fig. Figure 3 is a graph showing the air void reduction of a cement mortar mix at different defoamer loadings. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0012] The embodiments of the present disclosure will now be described in more detail below with reference to the accompanying drawings in which some, but not all, embodiments of the disclosure are illustrated.

[0013] The present disclosure will be better understood with reference to the following definitions. As used herein, the words "a / an" and the like have the meaning of "one or more." When a numerical limit or range is specified in the description of this disclosure, the endpoints are included unless otherwise noted. It is further to be understood that the terms "comprises" and / or "comprising," when used in this description, indicate the presence of the specified features, integers, steps, acts, elements, and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, acts, elements, components, and / or groups thereof.

[0014] The words "about," "approximately," or "substantially equal," as used herein, may be used to indicate that the described value and / or position is within a reasonable expected range of value and / or position. For example, a numerical value may have a value that is + / - 0.1% of the stated value (or range of values), + / - 1% of the stated value (or range of values), + / - 2% of the stated value (or range of values), + / - 5% of the stated value (or range of values), + / - 10% of the stated value (or range of values), or + / - 20% of the stated value (or range of values). When a numerical limit or range is stated in the description of this disclosure, the endpoints are included unless otherwise noted. In addition, all values ​​and subranges within a numerical limit or range are expressly included, as if explicitly spelled out.

[0015] The term “compound” as used herein refers to a chemical entity, whether as a solid, liquid or gas, and whether in the raw mixture or isolated and purified.

[0016] As used herein, the term "composite" refers to the combination of two or more different materials into a single one. At the atomic level, the individual components remain separate and distinguishable in the finished structure. The materials may have different physical or chemical properties, such that when combined, they produce a material with different characteristics than the original components. In some embodiments, a composite may comprise at least two constituents that have the same empirical formula but differ in densities, crystal phases, or the absence of a crystal phase (i.e., an amorphous phase).

[0017] The present disclosure is intended to include all hydration states of a given compound or formula, unless otherwise specified or the material is heated. Furthermore, the present disclosure is intended to include all isotopes of atoms present in the present compounds and complexes. Isotopes include atoms with the same atomic number but different mass numbers. As a general example and without limitation, hydrogen isotopes include deuterium and tritium. Carbon isotopes include 13 C and 14 C. Nitrogen isotopes include 14 N and 15 N. Oxygen isotopes include 16 O, 17 O and 18O. Isotopically labeled compounds of the disclosure can generally be prepared by conventional techniques or methods analogous to those described herein, known to those skilled in the art, using a suitable isotopically labeled reagent in place of the otherwise employed unlabeled reagent.

[0018] References to compounds in their salt form can be understood to include references to their acid form and vice versa, because it may be the case that both acid and salt forms can coexist in the aqueous environment. Similarly, references to compounds in their amine form can be understood to include references to their ammonium form and vice versa.

[0019] The term "cementitious" as used herein refers to materials that contain or consist of cement (e.g., Portland cement) or that otherwise act as a binding agent to hold together fine aggregates (e.g., sand), coarse aggregates (e.g., crushed stone), or mixtures thereof. A cementitious component may be particulate. The term "cement" as used herein includes hydratable cement made by pulverizing clinker consisting of hydraulic calcium silicates and one or more forms of calcium sulfate (e.g., gypsum) as an admixture. In all embodiments disclosed herein, any type of cement or cementitious material may be used.For example, cement may include Type I, Type IA, Type II, Type IIa, Type III, Type IIIa, Type IV, and Type V Portland cements (using either the ASTM C150 standard or the European standard EN-197), hydraulic cements, non-hydraulic cements, Portland fly ash cement, Portland pozzolanic cement, Portland silica fume cement, masonry cement, mortars, EMC cements, stuccos, plastic cements, expansive cements, white blend cements, pozzolan-lime cements, slag-lime cements, supersulfated cements, calcium aluminate cements, calcium sulfoaluminate cements, geopolymer cements, Rossendale cements, polymer cement mortars, lime mortars, and / or pozzolanic mortars. The term "mortar" refers to cement compositions that include one or more fine aggregates such as sand or other fine-grained materials. In one embodiment, SiO2 may be present in the cement.

[0020] Cement may include SiO2-containing materials including, but not limited to, belite (2CaO·SiO2), alite (3CaO·SiO2), celite (3CaO·Al2O3) or brownmillerite (4CaO·Al2O3·Fe2O3), which are commonly found in sand-free cement.

[0021] "Mortars" are cement pastes mixed with water that also contain fine aggregates (e.g. sand), while "concretes" are mortars that also contain coarse aggregates (e.g. crushed stone or gravel).

[0022] Typically, Portland cement is combined with one or more other cementitious materials ("SCMs") and provided as a mixture. SCMs may include limestone, slaked lime, fly ash, blast furnace slag, and silica fume, or other materials commonly found in such cements. Cementitious materials may therefore include one or more SCMs, preferably in an amount of 0%-100%, more preferably 10%-60%, based on the total dry weight of the cementitious material.

[0023] The term "hydratable" as used herein shall refer to cement or cementitious materials that harden by chemical reaction with water. Portland cement clinker is a partially molten mass composed primarily of hydratable calcium silicates. The calcium silicates are essentially a mixture of tricalcium silicate (3CaO·Al2O2, "C3S" in cement chemical notation) and dicalcium silicate (2CaO·SiO2, "C2S"), the former being the predominant form with minor amounts of tricalcium aluminate (3CaO·Al2O3, "C3A") and tetracalcium aluminoferrite (4CaO·Al2O3·Fe2O3, "C4AF"). See, for example, Dodson, Vance H., Concrete Admixtures (Van Nostrand Reinhold, New York, NY 1990), page 1, incorporated by reference in its entirety.

[0024] The term "admixture" shall be used herein to describe additives added at the cement factory, as well as "admixtures" added to cement, water, and optional aggregates used in the manufacture of cement mortars, concrete, and other cementitious materials. Preferably, the additive compositions are aqueous liquids capable of being dispensed in liquid form.

[0025] According to a first aspect, the present disclosure provides a defoamer for reducing air entrapment, which refers to air or any gas or collection of gases that may be present in the mixture. By reducing air entrapment, the defoamer, when added to a mixture, facilitates the release of air from the mixture. The defoamer comprises a polyalkoxylated alkylpolyamine having a structure represented by formula (1) or formula (2), and salts thereof: R 1 - (N(R 2 ) -CH2-CH2-CH2) n -N-(R 3 ) (R 4 ) (1), R 1 -N (CH2-CH2-CH2-N (R 3 ) (R 4 ))2 (2), where, with regard to the defoaming power R 1is a branched or unbranched hydrocarbon chain having a length of preferably 1 to 20, 5 to 20, 12 to 18 or 14 to 18 carbons. In one embodiment, R 1 preferred tallow alkyl. With regard to solubility in water and defoaming power, R 2 and R 3 each independently represents at least one or more of H, an alkylene oxide or a polyalkylene oxide and n is preferably 1 to 50, 2 to 45, 3 to 40, 4 to 35, 5 to 30, 6 to 25, 7 to 20 or 8 to 15.

[0026] In a further embodiment, the defoamer comprises a polyalkoxylated alkyldiamine having a structure represented by formula (3) and salts thereof R 1 -N(R 2 )-CH2-CH2-CH2-N-(R 3 )2 (3), where, with regard to the defoaming power R 1is a branched or unbranched hydrocarbon chain having a length of preferably 1 to 20, 5 to 20, 10 to 20, 12 to 18 or 14 to 18 carbons. In one embodiment, R 1 preferred tallow alkyl and R 2 and R 3 each independently represents H, an alkylene oxide or a polyalkylene oxide.

[0027] In one embodiment, the alkylene oxide is propylene oxide, and / or ethylene oxide. In one embodiment, the alkylene oxide is propylene oxide and the polyalkylene oxide is polypropylene oxide. In one embodiment, the polyalkylene oxide comprises repeating groups of propylene oxide and / or ethylene oxide. With regard to water solubility and defoaming ability, a single polyalkylene oxide chain can comprise an average of 1-15 groups of propylene oxide and / or ethylene oxide, or preferably 1 to 12, 1 to 10, 2 to 8, 2 to 7, or 3 to 5 groups on average. In an embodiment in which both propylene oxide and ethylene oxide are present in the alkylene oxide and / or the polyalkylene oxide, a weight percentage of the propylene oxide relative to a combined weight of the propylene oxide and the ethylene oxide is preferably 50 wt% or more, 60 wt% or more, 70 wt% or more, 80 wt% or more, 90 wt% or more, from the viewpoint of defoaming ability.-% or more, 95 wt% or more or 100 wt%.

[0028] In an embodiment where the alkylene oxide is propylene oxide and the polyalkylene oxide is polypropylene oxide, a combined weight percentage of propylene oxide and polypropylene oxide in terms of defoaming ability is in a range of 45 to 75 wt%, preferably 50 to 70 wt%, more preferably 60 to 70 wt%, relative to the polyalkoxylated alkylpolyamine.

[0029] In one embodiment, in view of defoaming ability and water solubility, a weight percentage of propylene oxide is preferably in a range of 45 to 75 wt%, 50 to 70 wt%, or 55 to 65 wt%, based on a combined mass of the polyalkoxylated alkylpolyamine and the propylene oxide.

[0030] In one embodiment, in view of defoaming ability and economy, the defoamers are preferably prepared by reacting N-(tallow alkyl)dipropylenetriamine with propylene oxide, wherein a weight percentage of propylene oxide is in a range of 45 to 75 wt%, 50 to 70 wt%, or 55 to 65 wt%, relative to a combined mass of the N-(tallow alkyl)dipropylenetriamine and the propylene oxide.

[0031] In one embodiment, with regard to the defoaming ability, the defoamer preferably has a number-average molecular weight or weight-average molecular weight in a range of 350 to 5,000 g / mol, 400 to 4,000 g / mol, 500 to 2,000 g / mol, 600 to 1,000 g / mol or 700 to 800 g / mol.

[0032] The average molecular weight is determined by the quantified total amine number of the defoamers according to the invention. The total amine number is determined by neutralizing the amines present in the defoamer with a known acid and converting the amount of acid into potassium hydroxide units. The measurement was performed according to ASTM D 2073.

[0033] In other embodiments, the defoamer is not made from tallow alkylamine, but from an alkylamine derived from coconut oil, soybean oil, palm kernel oil, or mixtures thereof.

[0034] In other embodiments, the defoamer can be used in a wide range of applications, starting with any aqueous mixture where it is desirable to control the specific air content of the mixture, and especially in mixtures containing amphiphilic molecules. Non-limiting examples of such applications include, but are not limited to, building materials, coatings, and adhesives, especially pressure-sensitive adhesives.

[0035] Specific examples of building materials include self-leveling mortars, cement, grouts, finish coats, and screeds. The invention can be used in other building materials such as thermally insulating mortar tiles, autocatalytic mortar tiles, self-compacting concrete compositions, wet plasters, render compositions, offshore cement compositions, oilfield cement compositions, and pigment slurries. The invention is useful in the manufacture of cement products that include a grinding aid. In particular, the invention is useful in the manufacture of admixtures. Such admixtures include, but are not limited to, high water reduction admixtures, superplasticizing admixtures, retarding admixtures, shotcrete admixtures, foam concrete admixtures, and strength-enhancing admixtures.Specific examples of coatings in which the present invention can be used include overprint varnishes, plastic coatings, and clear coats. Additional non-limiting examples of applications for the air entrainment removal composition of the present invention include ink formulations and manufacture, inkjet ink formulations and manufacture, metalworking fluids, and industrial and institutional cleaning compositions.

[0036] Without being bound by theory, it is believed that amine moieties present in the defoamer structure of the invention are ionized and thereby solubilized by acid species present in flow agents to yield stable, homogeneous mixtures. The degree of propylene oxide incorporation achieves a solubility of the defoamer in low pH formulations that is not observed with other similar structures. Addition of the defoamer to cement, which has a high pH, ​​neutralizes the defoamer of the invention to a more hydrophobic species, which ensures disruption of the lipid bilayer. The defoamer has a surfactant structure with a relatively hydrophilic head group at the propylene oxide end of the molecule, while the branched or unbranched hydrophobic hydrocarbon chain (R 4) is highly hydrophobic and is likely to be transported into the foam lamellae, destabilizing and dehumidifying the foam lamellae, resulting in suppression of foam formation during application.

[0037] According to a second aspect, the present disclosure provides an additive for reducing air entrapment, for example in a mortar or cement composition.

[0038] In one embodiment, the additive comprises the defoamer of the first aspect of the disclosure and an alkaline aqueous solution, an alkaline aqueous suspension, or an alkaline aqueous slurry. Examples of the alkaline aqueous solution, suspension, or slurry include, but are not limited to, incineration ash suspensions, hydraulic compositions, and cement compositions, preferably cement compositions.

[0039] In one embodiment, the additive comprises a dispersant, the defoamer of the first aspect of the disclosure, and water. In view of defoaming ability and storage stability, the dispersant and defoamer may be present in a combined concentration ranging from 25 to 35 wt%, 27 to 33 wt%, 29 to 31 wt%, or about 30 wt%, relative to the total weight of the additive. In view of defoaming ability and storage stability, the defoamer is preferably present in a concentration of 0.1 to 20 wt%, 0.2 to 18 wt%, 0.4 to 16 wt%, 0.5 to 15 wt%, 0.7 to 13 wt%, 1 to 12 wt%, 3 to 10 wt%, 4 to 9 wt%, or 5 to 8 wt%, relative to the weight of the dispersant.

[0040] In one embodiment, the additive preferably has a pH in a range of 4.5 to 6.5, 4.6 to 6.4, 4.8 to 6.2 or 5.0 to 6.0 with regard to storage stability.

[0041] In one embodiment, the dispersant is a superplasticizer. As used herein, the term "superplasticizer" refers to one or more materials capable of imparting improved flow properties and performance efficiency to mixtures such as curable compounds, including cementitious compositions, mortars and mortar tiles, grouts, screeds, pigment slurries, plasters, overprint varnishes, coatings, and adhesives. As used herein, the term "superplasticizer" refers to both plasticizer and superplasticizer chemicals. In one embodiment, the superplasticizer is selected from the group consisting of a polycarboxylate ether, a sulfo-modified melamine-formaldehyde condensate, a melamine-formaldehyde condensate, a sulfonated melamine-formaldehyde condensate, a lignin salt, a naphthalenesulfonate, a polycarboxylated acrylic, a polycarboxylated ether, a cocomide derivative, and mixtures thereof.

[0042] In one embodiment, the flow agent is a sulfo-modified melamine-formaldehyde condensate, for example, a melamine-formaldehyde sulfonate (MFS) or a sulfonated melamine-formaldehyde condensate. With regard to processability, the dispersant is preferably a polycarboxylate ether in one embodiment, and in another embodiment, the dispersant may comprise pendant polyethylene oxide groups.

[0043] Flow agent, polycarboxylate ether copolymer

[0044] In one embodiment, the flow agent is a polycarboxylate ether copolymer including a constituent unit (4) represented by the following formula (4) and a constituent unit (5) represented by the following formula (5): where R 5 and R 7 are the same or different and each represents a hydrogen atom or a methyl group, R 6 and R 8are the same or different and each represents a hydrogen atom or an alkyl group having 1 or more and 3 or less carbons, M represents a hydrogen atom, an alkali metal, an alkaline earth metal, ammonium or an organic ammonium, p represents a number of 0 or more and 2 or less, q represents a number of 0 or 1 and n1 represents an average number of moles added and represents a number of 5 or more and 150 or less.

[0045] In the constituent unit (4) represented by formula (4), R 5a hydrogen atom or a methyl group, and preferably includes a methyl group. M is a hydrogen atom, an alkali metal, an alkaline earth metal, ammonium, or an organic ammonium, and preferably an alkali metal or an alkaline earth metal. Two or more constituent units (4) may be present. Examples of a monomer that can be the constituent unit (4) include a monomer selected from acrylic acid, methacrylic acid, and salts thereof. In view of storage stability and defoaming ability, methacrylic acid and its salts are preferred.

[0046] In the constituent unit (5) represented by formula (5), R 6 and R 8same or different and, in view of reactivity, each represents a hydrogen atom or an alkyl group having 1 or more and 3 or less carbons, and, in view of storage stability, each preferably represents an alkyl group having 1 carbon, ie, a methyl group. Furthermore, R 7 a hydrogen atom or a methyl group, and in view of storage stability, preferably a hydrogen atom. Two or more constituent units (5) may be present. p represents a number of 0 or more and 2 or less, and is preferably 0 or more and 1 or less, and in view of storage stability, preferably 0. q represents a number of 0 or 1, and in view of storage stability, is preferably 1.

[0047] n1 is an average number of moles added and represents a number of 5 or more and 150 or less. In view of storage stability, n1 is preferably 15 or more, and n is preferably 140 or less, more preferably 130 or less, and further preferably 120 or less.

[0048] In another aspect of the present invention, in view of storage stability and cement dispersibility, n1 is preferably 15 or greater, and n is preferably 140 or less, more preferably 130 or less, further preferably 120 or less, further preferably 100 or less, further preferably 80 or less, further preferably 70 or less, further preferably 60 or less, further preferably 50 or less, further preferably 40 or less, and further preferably 30 or less.

[0049] In another aspect of the present invention, in view of the storage stability and the strength of the hydraulic composition, the range of n1 may be 80 or greater and 150 or less, preferably 140 or less, more preferably 130 or less, and more preferably 120 or less.

[0050] In one embodiment, the constituent unit (5) may be a monomer selected from the group consisting of methoxypolyethylene glycol monomethacrylate, polyoxyethylene methallyl ether, polyoxyethylene isoprenyl ether, and polyoxyethylene vinyl ether. Methoxypolyethylene glycol monomethacrylate is preferred in view of storage stability and defoaming ability.

[0051] In one embodiment, in view of the fluidity-maintaining performance, the polycarboxylate ether copolymer includes a constituent unit (6) represented by the following formula (6): where R 9a hydrocarbon group having 1 or more and 4 or fewer carbons, which may include heteroatoms.

[0052] R 9 in the formula (6) represents a hydrocarbon group having 1 or more and 4 or more carbons which may include heteroatoms, and is preferably a hydroxyethyl group or a methyl group.

[0053] The constituent unit (6) is preferably a constituent unit having a compound selected from alkyl (having 1 or more and 4 or less carbons) acrylates and alkyl (having 1 or more and or less carbons) methacrylates as a monomer.

[0054] The polycarboxylate ether copolymer is preferably a copolymer including constituent unit (4), constituent unit (5), and optionally constituent unit (6). In one embodiment, a proportion of the constituent unit (4) from the viewpoint of cement dispersibility is 45 mol% or more and 95 mol% or less, a proportion of the constituent unit (5) is 5 mol% or more and 30 mol% or less, and a proportion of the constituent unit (6) is 0 mol% or more and 35 mol% or less, relative to the total number of moles of the constituent units (4) to (6).

[0055] In view of cement dispersibility and storage stability, a proportion of the constituent units (4) in the copolymer, which are monomers, is, in one embodiment, 55 mol% or more, and preferably 65 mol% or more, more preferably 70 mol% or more and 90 mol% or less, more preferably 85 mol% or less, and more preferably 80 mol% or less, relative to the total number of moles of the constituent units (4) to (6).

[0056] In one embodiment, a proportion of the constituent units (5) in the copolymer which are monomers is preferably 10 mol% or more, more preferably 15 mol% or more, and 25 mol% or less, and more preferably 20 mol% or less, relative to the total number of moles of the constituent units (4) to (6).

[0057] In one embodiment, a proportion of the constituent units (6) in the copolymer which are monomers is preferably 5 mol% or more, more preferably 10 mol% or more and 25 mol% or less, and more preferably 15 mol% or less, relative to the total number of moles of the constituent units (4) to (6).

[0058] In one embodiment, a molar ratio of the constituent unit (4) to the constituent unit (5) in the polycarboxylate ether copolymer, constituent unit (4) / constituent unit (5), is preferably 1 or more, more preferably 3 or more, preferably 20 or less, and more preferably 10 or less, in view of cement dispersibility.

[0059] In one embodiment, a proportion of the total number of moles of the constituent units (4) and (5) relative to all the constituent units of the polycarboxylate ether copolymer is preferably 80 mol% or more, and more preferably 90 mol% or more, and preferably 100 mol% or less, or preferably 100 mol%.

[0060] In one embodiment, a proportion of the total number of moles of the constituent units (4), (5) and (6) relative to all the constituent units of the polycarboxylate ether copolymer is preferably 80 mol% or more, more preferably 90 mol% or more, and preferably 100 mol% or less, or preferably 100 mol%.

[0061] In one embodiment, a weight-average molecular weight (Mw) of the polycarboxylate ether copolymer is preferably 20,000 or more, more preferably 25,000 or more, further preferably 30,000 or more, and even more preferably 35,000 or more, and preferably 70,000 or less, more preferably 60,000 or less, and further preferably 55,000 or less in view of cement dispersibility. This weight-average molecular weight is measured by gel permeation chromatography (GPC) under the following conditions: GPC conditions Device: GPC (HLC-8320GPC), manufactured by Tosoh Corporation Column: G4000PWXL + G2500PWXL (manufactured by Tosoh Corporation) Eluent: 0.2 M phosphate buffer / CH3CN = 9 / 1 Flow rate: 1.0 mL / min Column temperature: 40°C Detection: RI Sample size: 0.2 mg / mL Standard substance: expressed in polyethylene glycol (monodisperse polyethylene glycol: molecular weight 87,500, 250,000, 145,000, 46,000, 24,000).

[0062] In one embodiment, the additive, upon formation, is a clear, homogeneous solution that does not develop phase separation and does not develop turbidity or cloudiness over an extended period of time. In other words, the solution does not develop turbidity or a noticeable degree of precipitated solids. For example, the turbidity measured in nephelometric units (NTU) by USEPA Method 180.1 may be 100 or less, 80 or less, 60 or less, 50 or less, or 40 or less, with a lower NTU value indicating less turbidity and greater transparency.

[0063] In one embodiment, the additive must not separate or develop cloudiness or haze for at least 7 days, at least 10 days, at least 14 days, at least 15 days, at least 20 days, at least 25 days, at least 30 days, at least 35 days, or at least 40 days. In another embodiment, the additive must not separate or develop cloudiness or haze over such periods, even when maintained at a temperature of at least 20°C, at least 30°C, at least 35°C, at least 40°C, at least 50°C, at least 55°C, and / or less than 60°C or less than 50°C.

[0064] According to a third aspect, the present disclosure provides a cement mixture comprising a particulate cementitious component, the admixture of the second aspect of the disclosure, and water. In view of workability, the solid content of the admixture in the cement mixture is preferably present in a range of 0.05 to 1 wt%, 0.08 to 0.8 wt%, 0.1 to 0.5 wt%, 0.2 to 0.4 wt%, based on the weight of the cement.

[0065] In one embodiment, the cement mixture has a W / C ratio (water / cement mass ratio) of 0.37 to 0.50, 0.38 to 0.48, 0.39 to 0.46, 0.40 to 0.45 or 0.42 to 0.44.

[0066] In one embodiment, the cement mixture further comprises 45 to 60 wt%, 48 to 58 wt%, 50 to 57 wt%, 52 to 56 wt%, or about 55 wt% sand, relative to the total weight of the cement mixture, or the cement mixture further comprises the sand in a concentration of 140 to 180 wt%, 150 to 175 wt%, or 160 to 170 wt%, based on the weight of the cement.

[0067] In one embodiment, the cement mixture exhibits an 80% or greater reduction in air voids compared to a substantially identical cement mixture not including the defoamer. For example, the air void reduction may be 85% or greater, 90% or greater, 95% or greater, 97% or greater, or 98% or greater. In one embodiment, the cement mixture may exhibit a 100% reduction in air voids, meaning no air voids are detected.

[0068] In one embodiment, air voids measured by ASTM D 3202-94 are present in the cement mixture at a concentration of 0.10% or less, 0.08% or less, 0.06% or less, 0.05% or less, 0.04% or less, or 0.03% or less.

[0069] In another aspect, the present disclosure relates to a method for forming an additive, the method comprising mixing an alkaline aqueous solution, suspension or slurry and a defoamer described herein.

[0070] According to a further aspect, the present disclosure relates to a method of forming a cement mixture, the method comprising mixing a particulate cementitious component, the admixture of the second aspect, and water.

[0071] According to a further aspect, the present disclosure relates to a method of forming a cementitious mixture, the method comprising mixing a particulate cementitious component, the defoamer of the first aspect, a dispersant, and water.

[0072] In another aspect, the present disclosure relates to a method for reducing air entrainment in a cement mixture, the method comprising mixing the admixture of the second aspect with a cement mixture having air entrainment, wherein an amount of air entrainment as measured by ASTM D 3203-94 is reduced by 80% or more, 85% or more, 90% or more, 95% or more, or 97% or more, relative to a substantially similar cement mixture mixed with a substantially similar admixture that does not include the defoamer of the first aspect.

[0073] According to a further aspect, the present disclosure relates to a method for reducing air voids in a cement mixture, the method comprising mixing the defoamer of the first aspect and a dispersant with a cement mixture.

[0074] According to a further aspect, the present disclosure relates to a use for a defoamer comprising a polyalkoxylated alkylpolyamine having a structure represented by formula (2) and salts thereof R 1 -N(CH2-CH2-CH2-N(R 3 )(R 4 ))2 (2), where R 1 is a branched or unbranched hydrocarbon chain of 1 to 20 carbons in length and R 2 , R 3 and R 4 each independently represents H, an alkylene oxide or a polyalkylene oxide.

[0075] According to a further aspect, the present disclosure relates to a use of the defoamer for an alkaline aqueous solution, suspension or slurry.

[0076] According to a further aspect, the present disclosure relates to a use of the defoamer for a hydraulic composition.

[0077] In other embodiments, the defoamer can be combined with additional components. The resulting compositions can be incorporated into cement, mortar, concrete compositions, overprint varnishes, plastic coatings, clear coats, inks, dyes, or other suitable applications.Examples of suitable additional components include wetting agents, flow and leveling agents, shrinkage reducing agents, naphthalene sulfonates, polystyrene sulfonates, phosphates, phosphonates, crosslinked homo- or co-polymers of acrylic acid and salts thereof, calcium salts of organic acids, preferably having 1 to about 4 carbon atoms, alkanoic acids and salts thereof, aluminum sulfate, metallic aluminum, bentonite, montmorillonite, sepiolite, polyamide fibers, polypropylene fibers, polyvinyl alcohol and homo-, co- or terpolymers based on vinyl acetate, maleic acid esters, ethylene, styrene, butadiene, vinyl versatate and acrylic monomers and redispersible dispersion powders such as polyvinyl acetate, polyethylene-polyvinyl acetate, polyvinyl alcohol and homo-, co- or terpolymers based on vinyl acetate, maleic acid esters, ethylene, styrene, butadiene, vinyl versatate and acrylic acid monomers.Other suitable components include short and long fibers such as steel, glass, carbon, polyolefin, polyester, and polyamide fibers. Rheology modifiers (cellulosic and polysaccharide additives including starch, biopolymers such as xanthan gum) and alkaline swellable acrylic associative thickeners (containing cellulose and / or methyl (acrylic acid) functionalities) may also be used, as may fine and / or coarse aggregates and / or fillers such as sand or clay. Other inorganic cement components such as gypsum, blast furnace slag, fly ash, aluminum sulfate, metallic aluminum, bentonite, montmorillonite, and sepiolite may be included, as well as dyes, pigments, and micronized colorants. Other functional additives include setting accelerators and / or retarders, water repellents, hydrophobic agents, corrosion inhibitors, flame retardants, biocides, and fungicides.

[0078] The following are exemplary embodiments of the present disclosure:

[0079] Embodiment (1): Defoamer for reducing air entrapment in an alkaline aqueous solution, suspension or slurry, comprising a polyalkoxylated alkylpolyamine having a structure represented by formula (1) or (2) and salts thereof R 1 -(N(R 2 )-CH2-CH2-CH2) n -N-(R 3 )(R 4 ) (1), R 1 -N(CH2-CH2-CH2-N(R 3 )(R 4 ))2 (2), where R 1 is a branched or unbranched hydrocarbon chain having a length of 1 to 20 carbons, R 2 , R 3 and R 4 each independently represents at least one or more of H, an alkylene oxide or a polyalkylene oxide and n is 1 to 50.

[0080] Embodiment (2): Defoamer for reducing air entrapment in an alkaline aqueous solution, suspension or slurry, comprising a polyalkoxylated alkyldiamine having a structure represented by formula (3) and salts thereof R 1 -N(R 2 )-CH2-CH2-CH2-N-(R 3 )2 (3), where R 1 is a branched or unbranched hydrocarbon chain having a length of 1 to 20 carbons, R 2 and R 3 each independently represents H, an alkylene oxide or a polyalkylene oxide.

[0081] Embodiment (3): Defoamers according to embodiment (1) or (2), wherein the alkylene oxide is propylene oxide or ethylene oxide.

[0082] Embodiment (4): Defoamers according to any one of embodiments (1) to (3), wherein the polyalkylene oxide comprises repeating groups of polypropylene oxide and / or ethylene oxide.

[0083] Embodiment (5): Defoamer according to any one of embodiments (1) to (4), wherein the alkylene oxide is propylene oxide and the polyalkylene oxide is polypropylene oxide.

[0084] Embodiment (6): Defoamers according to any one of embodiments (1) to (5), wherein R 1 a branched or unbranched hydrocarbon chain with a length of 12 to 18 carbons.

[0085] Embodiment (7): Defoamer according to any one of embodiments (1) to (6), wherein a combined weight percentage of propylene oxide and polypropylene oxide is in a range of 45 to 75 wt% relative to the polyalkoxylated alkylpolyamine.

[0086] Embodiment (8): An additive comprising the defoamer according to any one of embodiments (1) to (7) and an alkaline aqueous solution, suspension or slurry.

[0087] Embodiment (9): An additive for reducing air entrapment, comprising: a dispersant, the defoamer according to any one of embodiments (1) to (7), and water. The dispersant and defoamer are present in a combined concentration ranging from 25 to 35 wt.% relative to the total weight of the additive, and the defoamer is present in a concentration of 0.1 to 20 wt.% relative to the weight of the dispersant.

[0088] Embodiment (10): Additive according to embodiment (9), wherein the defoamer is present in a concentration of 4 to 15 wt.% relative to the total weight of the dispersant.

[0089] Embodiment (11): Additive according to embodiment (9) or (10), which has a pH in a range of 4.5 to 6.5.

[0090] Embodiment (12): Additive according to any one of embodiments (9) to (11), wherein the dispersant is a flow agent selected from the group consisting of a polycarboxylate ether, a sulfomodified melamine formaldehyde condensate, a melamine formaldehyde condensate, a sulfonated melamine formaldehyde condensate, a lignin salt, a naphthalenesulfonate, a polycarboxylated acrylic, a polycarboxylated ether, a carboxylic acid salt, casein, a cocomide derivative, and mixtures thereof.

[0091] Embodiment (13): The additive according to any one of embodiments (9) to (12), wherein the dispersant is at least one selected from the group consisting of a polycarboxylate ether, an ester type dispersant, an ether type dispersant, and a naphthalene type dispersant.

[0092] Embodiment (14): Additive according to any one of embodiments (9) to (13), wherein the dispersant is a polycarboxylate ether comprising pendant polyethylene oxide groups.

[0093] Embodiment (15): Cement mixture comprising a particulate cementitious component, the admixture according to any one of embodiments (9) to (14) and water, wherein a solids content of the admixture is present in the cement mixture in a concentration in a range of 0.05 to 1 wt% based on the weight of the cement.

[0094] Embodiment (16): Cement mixture according to embodiment (15), wherein the solid content of the admixture is present in the cement mixture in a concentration in a range of 0.1 to 0.5 wt%, based on the weight of the cement.

[0095] Embodiment (17): Cement mixture according to embodiment (15) or (16), which has a W / C ratio of 0.37 to 0.50.

[0096] Embodiment (18): Cement mixture according to any one of embodiments (15) to (17), further comprising 45-60 wt% sand, relative to the total weight of the cement mixture.

[0097] Embodiment (19): A method for forming an additive, the method comprising mixing an alkaline aqueous solution, suspension or slurry and the defoamer according to any one of embodiments (1) to (7).

[0098] Embodiment (20): A process for forming a cement mixture, the process comprising mixing a particulate cementitious component, the defoamer according to any one of embodiments (1) to (7), a dispersant, and water. The admixture is present in the cement mixture at a solids content concentration in a range of 0.05 to 1 wt.%, based on the weight of the cement.

[0099] Embodiment (21): A method for forming a cement mixture, the method comprising mixing a particulate cementitious component, the admixture according to any one of embodiments (9) to (14), and water. The admixture is present in the cement mixture at a solids content concentration in a range of 0.05 to 1 wt.%, based on the weight of the cement.

[0100] Embodiment (22): A method for reducing air voids in a cement mixture, the method comprising: Mixing the defoamer according to claim 1 or 2 and a dispersant with a cement mixture.

[0101] Embodiment (23): Use for a defoamer comprising polyalkoxylated alkylpolyamine having a structure represented by formula (1) or (2) and salts thereof R 1 -(N(R 2 )-CH2-CH2-CH2) n -N-(R 3 )(R 4 ) (1), R 1 -N(CH2-CH2-CH2-N(R 3 )(R 4 ))2 (2), where R 1 is a branched or unbranched hydrocarbon chain having a length of 1 to 20 carbons, R 2 , R 3 and R 4 each independently represents H, an alkylene oxide or a polyalkylene oxide and n is 1 to 50.

[0102] Embodiment (24): Use for the defoamer according to embodiment (23) for an alkaline aqueous solution, suspension or slurry.

[0103] Embodiment (25): Use for the defoamer according to embodiment (23) for a hydraulic composition.

[0104] The following examples are intended to further illustrate the protocols for preparing the defoamer and additive and their use and are not intended to limit the scope of the claims. EXAMPLES

[0105] Aqueous dispersant and defoamer mixtures with different defoamer loadings were prepared, keeping the total active content constant at 30 wt.%. Polymers M-1, M-2, and M-3 are ester-type polycarboxylate dispersant flow aids and are commercially available from Kao Specialties Americas, High Point, NC. Specifically, Polymer M-1 was composed of an aqueous copolymer of sodium ethacrylate and methoxypolyoxyethylene(100) methacrylate (80 / 20 mol%), Mw: 50,000, with a solids content of 40%. Polymer M-2 was composed of an aqueous copolymer of sodium methacrylate and methoxypolyoxyethylene(20) methacrylate (70 / 30 mol%), Mw: 50,000, with a solids content of 50%. Polymer M-3 was composed of an aqueous copolymer of sodium ethacrylate and methoxypolyoxyethylene(100)methacrylate (90 / 10 mol%), Mw: 40,000, with a solids content of 40%.Polymer M-4 is a commercially available naphthalenesulfonic acid formaldehyde condensate flow agent (e.g., MIGHTY 150 from Kao Corporation, Tokyo, JP). Polymer M-5 is an ether-type polycarboxylate dispersant composed of an aqueous copolymer of sodium acrylate and polyoxyethylene(50) methallyl ether (85 / 15 mol%), Mw: 40,000, with a solids content of 50%.

[0106] Defoamers widely accepted in this industry with different functionalities such as esters, silicones and non-ionic alkoxylates all separated into two phases after 2-3 days at 50°C as shown in Table 4 and Fig.1. Amine-based defoamers disclosed in the prior art, such as ethylenediamine block polyoxyether and alkyl ether amine, provided stable solutions, while a tertiary alkylamine was unstable. Aqueous dispersant solutions including the amine defoamers of the present invention were all comparatively stable at 50°C for extended periods, as shown in Tables 4 and 5. Table 1: Defoamer compositions Defoamer test Diamine (triamine) Propylene oxide wt.% S1 N-(tallow alkyl)trimethylenediamine 51 S2 N-(tallow alkyl)trimethylenediamine 61 S3 N-(tallow alkyl)trimethylenediamine 72 S4 N-(oleyl)trimethylenediamine 50 S5 N-(Cocoalkyl)trimethylenediamine 56 S6 N-(tallow alkyl)dipropyltriamine 55

[0107] The homogeneous solution can be Fig.2. A typical limitation for aqueous defoamers and polycarboxylate blends is that the hydrophobic defoamer can only be formulated at restricted concentrations to avoid separation. The inventive defoamer S2 underscores that this defoamer can be incorporated without restriction at 12% of the dispersant formulation (loading based on active PCE). At both low and high loadings of the inventive defoamer, the blend with the dispersant produces clear and stable solutions.

[0108] The defoamer properties of various polyalkoxylated alkylpolyamine admixtures were evaluated in a standard mortar test for air void content. Type I ordinary Portland cement with a sand / cement / water ratio of 2.2 / 1.3 / 0.5 was used. All tests were conducted in the presence of a superplasticizer / dispersant. The dispersant dosage was 0.10% (active) based on the weight of the cement, and the defoamer to dispersant ratio was 0.10% active by weight. Air void content was measured according to ASTM D 3203-94 using a 400 ML gauge with a 3-inch inner diameter in accordance with ASTM C-185.

[0109] Various polyalkoxylated alkylpolyamines were compared with widely used defoamers in the industry in comparative examples, as shown in Table 2 with the ester-type polycarboxylate dispersant M-1. The defoaming ability of the inventive defoamer S2 was compared with the ether-type polycarboxylate dispersant composed of an aqueous copolymer of sodium acrylate and polyoxyethylene(50) methallyl ether (85 / 15 mol%) with a solid content of 50%, as shown in Table 3. Table 2: Comparative effect of defoamers on mortar air sample control with ester-type polycarboxylate dispersant M-1 Sample information Defoamer / (active) dispersant (%) Air pores (%) Control (no defoamer) 0 5,22 Ester defoamer 0, 1 1,21 0,5 0, 18 Silicone defoamer 0, 1 1,42 Ethylenediamine block POE defoamer 0, 1 2,36 0,5 2,35 Tert-alkylamine defoamer 0, 1 2, 08 0,5 1,38 Defoamer S1 0, 1 -1,12 0,5 -1,44 Defoamer S2 0, 1 -1,40 0,5 -1,85 Defoamers S3 0, 1 -1,04 0,5 -1, 16 Defoamer S4 0, 1 -1,04 0,5 -1, 16 Defoamer S5 0, 1 -0, 83 0,5 -1,24 Defoamer S6 0, 1 -0,70 0,5 -1,68 Table 3. Effect of defoamer S2 on mortar air void control with ether-type polycarboxylate dispersant Sample information Defoamer / (active) dispersant (%) Air pores (%) Control (no defoamer) 0 7,56 Defoamer S2 0, 1 2, 87 0,5 0,74 Table 4: Comparative stability of defoamer / PCE solution with ester-type polycarboxylate dispersant M-2 Sample information Defoamer loading (wt%) Appearance of the PCE / defoamer mixture Stability in days at 50°C Ester defoamer 0,5 cloudy 3 Silicone defoamer 0,5 cloudy 2 Non-ionic alkoxylate defoamer 0,5 clear 3 Ethylenediamine block POE defoamer 0,5 clear 10+ Alkyl ether amine defoamer 0,5 cloudy 5+ Tert-alkylamine defoamer 0,5 cloudy 0 S1 0,5 cloudy 0 S2 0,5 clear 250+ 1,5 clear 250+ 5 clear 250+ 11 clear 300+ S3 0,5 clear 3 S4 5 clear 40+ S5 5 cloudy 3 S6 5 clear 40+ Table 5: Comparative stability of the defoamer-dispersant solution Dispersant type Dispersant information Sample information Defoamer loading (wt%) Appearance of the PCE / defoamer mixture Stability in days at 50°C Ester type MIGHTY 21ES Ester defoamer 0,5 cloudy 3 S2 0,5 clear 10+ 5 clear 250+ MIGHTY 21EG Ester defoamer 0,5 cloudy 3 S2 0,5 clear 10+ 5 clear 50+ Naphthalene derivative MIGHTY 150 Ester defoamer 0,5 cloudy 3 S2 0,5 clear 10+ 5 clear 50+ Ether type Sodium acrylate-POE(50) methallyl ether copolymer Ester defoamer 5 cloudy 2 S2 0,5 clear 40+ 5 clear 40+

[0110] Compared to the control mix without defoamer, the lower air voids with the inventive additives, which are the target of this invention, clearly indicate that the polyalkoxylated alkylpolyamine defoamers S1-S6 functioned effectively as foam control agents, achieving better air void reduction in the mortar mix than the industry-standard comparison defoamers. The results indicate that the defoamer functionality described in this invention outperforms conventional and known amine defoamers in the field.

[0111] The mortar test procedure described in the above example was repeated, except that the ratio of defoamer to active dispersant was 0.10 or 0.50 wt.%. The data in Table 2 show that the inventive defoamers S1-S6 all demonstrated a significant reduction in air voids, below the limit of the control example (ester defoamer). The air void reduction was further improved by increasing the defoamer concentration to 0.50 wt.%. All three inventive examples outperformed the industry standard comparisons and amine-based defoamers used in this example. The results are shown in Fig. 3 also shown graphically. Production of defoamer / PCE solutions at different defoamer loadings

[0112] Aqueous mixtures of a polycarboxylate dispersant and the polyalkoxylated alkylpolyamines of the invention were prepared to yield solutions with a solids content of 30% total weight. The two components were mixed for 30 minutes at room temperature at a final pH between 5-6. The resulting solution was clear and showed no separation or defoaming after prolonged storage at room temperature and 50°C over a period of one month ( Fig. 2). The polymeric dispersant comprised a backbone with polycarboxylate groups and pendant polyethylene oxide groups. The alkylpolyamines were derived from N-(tallow alkyl)trimethylenediamine, N-(oleyl)trimethylenediamine, N-(coco)trimethylenediamine, or N-(tallow alkyl)dipropylenetriamine, or had varying degrees of polypropoxylation, indicated by the weight % propylene oxide of the total molecular weight, which is listed in Table 1. QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] US 63 / 374,839

[0001] US 6,139,623

[0006] US 8,187,376

[0007] Cited non-patent literature

[0000] Dodson, Vance H., Concrete Admixtures (Van Nostrand Reinhold, New York NY 1990), page 1

[0023]

Claims

[1] Defoamer for reducing air entrapment in an alkaline aqueous solution, suspension or slurry, comprising a polyalkoxylated alkylpolyamine having a structure represented by formula (1) or (2) and salts thereof R 1 -(N(R 2 )-CH2-CH2-CH2) n -N-(R 3 )(R 4 ) (1), R 1 -N(CH2-CH2-CH2-N(R 3 )(R 4 ))2 (2), wherein R 1 a branched or unbranched hydrocarbon chain with a length of 1 to 20 carbons, R 2 , R 3 and R 4 each independently represents at least one or more of H, an alkylene oxide or a polyalkylene oxide and n is 1 to 50. [2] Defoamer for reducing air entrapment in an alkaline aqueous solution, suspension or slurry, comprising a polyalkoxylated alkyldiamine having a structure represented by formula (3) and salts thereof R 1 -N (R 2 )-CH2-CH2-CH2-N-(R 3 )2 (3), wherein R 1 a branched or unbranched hydrocarbon chain with a length of 1 to 20 carbons, R 2 and R 3 each independently represents H, an alkylene oxide or a polyalkylene oxide. [3] Defoamers according to claim 1, wherein the alkylene oxide is propylene oxide or ethylene oxide. [4] The defoamer according to claim 1, wherein the alkylene oxide is propylene oxide and the polyalkylene oxide is polypropylene oxide. [5] Defoamer according to claim 1, wherein R 1 a branched or unbranched hydrocarbon chain with a length of 12 to 18 carbons. [6] The defoamer of claim 4, wherein a combined weight percentage of propylene oxide and polypropylene oxide is in a range of 45 to 75 wt% relative to the polyalkoxylated alkylpolyamine. [7] Additives comprising: the defoamer according to claim 1 and an alkaline aqueous solution, suspension or slurry. [8] Additives for reducing air inclusions, comprising: a dispersant, the defoamer according to claim 1 and Water, wherein the dispersant and the defoamer are present in a combined concentration in a range of 25 to 35 wt.% relative to the total weight of the additive, and wherein the defoamer is present in a concentration of 0.1 to 20 wt.% relative to the weight of the dispersant. [9] Additive according to claim 8, wherein the defoamer is present in a concentration of 4 to 15 wt.% relative to the total weight of the dispersant. [10] Additive according to claim 8, which has a pH in a range of 4.5 to 6.

5. [11] The additive of claim 8, wherein the dispersant is a flow agent selected from the group consisting of a polycarboxylate ether, a sulfo-modified melamine formaldehyde condensate, a melamine formaldehyde condensate, a sulfonated melamine formaldehyde condensate, a lignin salt, a naphthalene sulfonate, a polycarboxylated acrylic, a polycarboxylated ether, a carboxylic acid salt, casein, a cocomide derivative, and mixtures thereof. [12] The additive according to claim 8, wherein the dispersant is at least one selected from the group consisting of a polycarboxylate ether, an ester type dispersant, an ether type dispersant and a naphthalene type dispersant. [13] An additive according to claim 8, wherein the dispersant is a polycarboxylate ether comprising pendant polyethylene oxide groups. [14] Cement mixture comprising: a particulate cementitious component, the additive according to claim 8 and Water, wherein a solids content of the admixture is present in the cement mixture in a concentration in a range of 0.05 to 1 wt.%, based on the weight of the cement. [15] Cement mixture according to claim 14, wherein the solids content of the admixture is present in the cement mixture in a concentration in a range of 0.1 to 0.5 wt% based on the weight of the cement. [16] Cement mixture according to claim 14, which has a W / C ratio of 0.37 to 0.

50. [17] Cement mixture according to claim 14, further comprising 45-60 wt% sand, relative to the total weight of the cement mixture. [18] A process for forming an additive, the process comprising: Mixing an alkaline aqueous solution, suspension or slurry and the defoamer according to claim 1. [19] A method of forming a cement mixture, the method comprising: Mixing a particulate cementitious component, of the additive according to claim 8 and Water, wherein the solids content of the admixture is present in the cement mixture in a concentration in a range of 0.05 to 1 wt.%, based on the weight of the cement. [20] A process for forming a cement mixture, the process comprising: Mixing a particulate cementitious component, of the defoamer according to claim 1, a dispersant and Water, wherein the solids content of the admixture is present in the cement mixture in a concentration in a range of 0.05 to 1 wt.%, based on the weight of the cement. [21] A method for reducing air voids in a cement mixture, the method comprising: Mixing the admixture according to claim 8 with a cement mixture. [22] A method for reducing air voids in a cement mixture, the method comprising: Mixing the defoamer according to claim 1 and a dispersant with a cement mixture. [23] Use for a defoamer comprising polyalkoxylated alkyltriamine having a structure represented by formula (1) or (2) and salts thereof R 1 -(N(R 2 )-CH2-CH2-CH2) n -N-(R 3 )(R 4 ) (1), R 1 -N(CH2-CH2-CH2-N(R 3 )(R 4 ))2 (2), wherein R 1 a branched or unbranched hydrocarbon chain with a length of 1 to 20 carbons, R 2 , R 3 and R 4 each independently represents H, an alkylene oxide or a polyalkylene oxide and n is 1 to 50. [24] Use for the defoamer according to claim 23 for an alkaline aqueous solution, suspension or slurry. [25] Use of the defoamer according to claim 23 for a hydraulic composition.

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