Coating composition comprising triglyceride alkoxylates

Abstract

Aqueous coating composition, comprising a) a binder; b) mixtures of glycerol ester alkoxylates selected from the substances of the following formula (I) wherein R1, R2 and R3 are independently linear or branched alkylene groups (CmH2m) with m being 2 or 3 or mixtures thereof; x, y and z are independently integers from 0 to 400 with at least one being ≥ 1; R4, R5 and R6 are independently hydrogen or C8- C30 acyl groups with at least one being acyl group; characterized in that x+y+z ≥ 95, at least 70 mol% of the glycerol ester alkoxylates of the formula (I) in the mixture have all of the groups R4, R5 and R6 with a meaning different from hydrogen; and at least 30 mol% of those groups R4, R5 and R6, which have a meaning different from hydrogen, are C16-C18 acyl groups; and c) water.

Description

[0001] Clariant International Ltd 1 KM

[0002] Coating composition comprising triglyceride alkoxylates

[0003] The present invention relates to aqueous coating compositions containing specific mixtures of glycerol ester alkoxylates or the alkoxylation products as rheology modifiers.

[0004] Aqueous coating compositions, also known as waterborne coatings, are coating formulations where water is used as the primary solvent or dispersing medium instead of organic solvents. Aqueous coatings offer several advantages over solventbased coatings, such as improved safety due to reduced flammability, and ease of application. They are widely used in various applications, including architectural coatings (paints, stains, varnishes), industrial coatings (for metal, wood, plastic), , among others.

[0005] Rheology modifiers are important additives in coatings formulations to adjust and control the flow behaviour and viscosity of the system. They contribute, for example, to the stability of the paint formulation during storage, preventing settling or separation of pigments and other solid particles, ensuring a homogeneous and consistent product. Furthermore, rheology modifiers can impart thixotropic behaviour, which means the paint exhibits high viscosity at low shear rates (during storage or after application) and low viscosity at high shear rates (during application). This thixotropic nature helps prevent sagging or dripping of the paint on vertical surfaces.

[0006] In addition to the technical requirements the sustainability aspects of coatings formulations are increasing more and more, with them the need for new rheology modifiers based on renewable based materials.

[0007] Although cellulose derivatives such as cellulose ethers are popular bio-based rheology modifiers, they have disadvantages like low water resistance and tendency to syneresis, among others. In addition, cellulose rheology modifiers have to be activated by a base to enhance their thickening efficiency.

[0008] CN1 11234199 discloses the preparation of ethoxylated natural vegetable oils under the action of ester group-inserted ethoxylation catalyst and their use as rheology modifiers and a latex coating wherein the ethoxylated natural vegetable oil is used together with a second rheology modifier and a cellulose.

[0009] It was an object of the present invention to provide new aqueous coating compositions comprising triglyceride alkoxylates, in which the triglyceride alkoxylates exhibit high thickening efficiency, being possible to be used as single rheology modifier, and in addition provide low tendency to sagging and high water resistance to the aqueous coating compositions.

[0010] It has been surprisingly found that glycerol ester alkoxylates having more than 95 alkoxy groups are suitable bio-based rheology modifiers in aqueous coatings compositions. They may be used as single rheology modifier in aqueous coating compositions and in addition provide low tendency to syneresis, sagging and water resistance to the aqueous coating composition.

[0011] In a first aspect, the present invention relates to an aqueous coating composition comprising a) a binder b) mixtures of glycerol ester alkoxylates selected from the substances of the following formula (I) wherein

[0012] R1, R2and R3are, independent from each other, selected from linear or branched alkylene groups (CmH2m) with m being 2 or 3 or mixtures thereof; x, y and z are, independently from each other, integer numbers from 0 to

[0013] 400, where at least one of the variables x, y and z is 1 or an integer number greater than 1 , and preferably integer numbers from 1 to 350, more preferably from 5 to 250;

[0014] R4, R5and R6are, independent from each other, selected from hydrogen and linear or branched, preferably linear, saturated or unsaturated acyl groups comprising from 8 to 30 carbon atoms or mixtures thereof, preferably are, independent from each other, selected from hydrogen and linear or branched, preferably linear, saturated or unsaturated acyl groups comprising from 12 to 30 carbon atoms or mixtures thereof, more preferably are, independent from each other, selected from hydrogen and linear or branched, preferably linear, saturated or unsaturated acyl groups comprising from 12 to 24 carbon atoms or mixtures thereof, even more preferably are, independent from each other, selected from hydrogen and linear or branched, preferably linear, saturated or unsaturated acyl groups comprising from 12 to 20 carbon atoms or mixtures thereof, and particularly preferably are, independent from each other, selected from hydrogen and linear or branched, preferably linear, saturated or unsaturated acyl groups comprising from 14 to 20 carbon atoms or mixtures thereof, and wherein in the definitions of R4, R5and R6above, at least one of R4, R5and R6has a meaning different from hydrogen; characterized in that x+y+z is, based on a molar average, a number equal to or greater than

[0015] 95, preferably a number from 95 to 500, more preferably from 95 to 450, even more preferably from 95 to 350, at least 70 mol%, preferably at least 75 mol%, more preferably at least 80 mol% and even more preferably at least 85 mol% of the glycerol ester alkoxylates of the formula (I) in the mixture, in each case based on the total amount of the glycerol ester alkoxylates of the formula (I) in the mixture, are glycerol ester alkoxylates of the formula (I), wherein all of the groups R4, R5and R6have a meaning different from hydrogen; and at least 30 mol%, preferably at least 40 mol%, more preferably at least 50 mol%, even more preferably at least 60 mol% and particularly preferably at least 70 mol% of those groups R4, R5and R6, which have a meaning different from hydrogen, are linear or branched, preferably linear, saturated or unsaturated acyl groups comprising 16 to 20 carbon atoms or mixtures thereof and preferably are linear or branched, preferably linear, saturated or unsaturated acyl groups comprising 16 to 18 carbon atoms or mixtures thereof, in each case based on the total amount of the linear or branched, preferably linear, saturated or unsaturated acyl groups R4, R5and R6, and c) water.

[0016] Component b) is referred to as a “mixture of glycerol ester alkoxylates of the formula (I)”. The expression “mixture” means the presence of compounds according to formula (I) that differ in at least one of R1, R2, R3, R4, R5, R6, x, y and z. It is to be understood that glycerol ester alkoxylates of the formula (I) inevitably will occur as a mixture of more than one individual compound. The expression “mixture” may therefore as well be read as “compounds”.

[0017] In the inventive aqueous coatings compositions containing mixtures of glycerol ester alkoxylates of the formula (I), those of the groups R4, R5and R6, which have a meaning different from hydrogen, are referred to as “acyl groups”.

[0018] In the inventive aqueous coatings compositions containing mixtures of glycerol ester alkoxylates of the formula (I), the single acyl groups R4, R5and R6consist of a carbonyl group C=O and a hydrocarbon residue, without further substituents, e.g. without hydroxyl groups, on the hydrocarbon residue.

[0019] More preferably, acyl groups R4, R5and R6are of the formula -C(=O)-R4a, -C(=O)- R5aand -C(=O)-R6a, respectively, wherein the residues R4a, R5aand R6acomprise one carbon atom less than the respective acyl groups R4, R5and R6and are, independent from each other, selected from linear or branched, preferably linear, saturated alkyl groups, linear or branched, preferably linear, mono- or polyunsaturated alkenyl groups, or mixtures thereof. For example, in this more preferred embodiment of the invention, in case R4, R5and R6are, independent from each other, selected from linear or branched, preferably linear, saturated or unsaturated acyl groups comprising from 8 to 30 carbon atoms or mixtures thereof, R4a, R5aor R6aare, independent from each other, selected from linear or branched, preferably linear, saturated alkyl groups comprising from 7 to 29 carbon atoms, linear or branched, preferably linear, mono- or polyunsaturated alkenyl groups comprising from 7 to 29 carbon atoms, or mixtures thereof.

[0020] In a single glycerol ester alkoxylate molecule of the formula (I), an acyl group R4, R5or R6forms an ester bond, either (i) with an oxygen atom of one of the structural units -[R1O]-, -[R2O]- or -[R3O]- or (ii) with an oxygen atom of the glycerol residue -0- CH2-CH(O-)-CH2-O-.

[0021] If present, the structural units -[R1O]-, -[R2O]- and -[R3O]- in the glycerol ester alkoxylates of the formula (I) are, independent from each other, selected from [(C2H4)O] or [(C3H6)O].

[0022] If present, the structural units of the formula -[R1O]x-, -[R2O]y- and -[R3O]z- in a single glycerol ester alkoxylate molecule of the formula (I), independent from each other, may consist of one or more [(C2H4)O]-groups, may consist of one or more [(C3He)O]- groups or may consist of a mixture of [(C2H4)O]- and [(C3He)O]-groups.

[0023] Within a single glycerol ester alkoxylate molecule of the formula (I), the structural units -[R1O]x-, — [R2O]y— and -[R3O]z- may be the same or different.

[0024] The groups [(C2H4)O], if present in the structural units of the formula -[R1O]x-, - [R2O]y— and / or -[R3O]z- of the glycerol ester alkoxylates of the formula (I), preferably are of the formula -CH2-CH2-O-. The groups [(CsHejO], if present in the structural units of the formula -[R1O]x-, - [R2O]y- and / or -[R3O]z- of the glycerol ester alkoxylates of the formula (I), preferably are of the formula -CH(CH3)-CH2-O- or -CH2-CH(CH3)-O-, i.e. of the formula

[0025] In the case that [(C2H4)O]- and [(CsHejjO-groups exist in a structural unit of the formula -[R1O]x-, -[R2O]y- and / or -[R3O]z- they may be arranged blockwise, alternating, periodically and / or statistically, preferably blockwise and / or statistically. This means that in a structural unit of the formula -[R1O]x-, -[R2O]y- and / or - [R3O]z-, the groups [(C2H4)O] and [(CsHejO] may be arranged, for example, in a purely statistically or blockwise form but may also be arranged in a form which could be considered as both, statistical and blockwise, e.g. small blocks of [(C2H4)O] and [(CsHejO] arranged in a statistical manner, or in a form wherein adjacent instances of statistical and blockwise arrangements of the groups [(C2H4)O] and [(CsHejO] exist.

[0026] Any of the groups [(C2H4)O] and [(CsHejO] can be linked to -R4, -R5, -R6and an oxygen of the glycerol backbone in a glycerol ester alkoxylate molecule of the formula (I). This means, for example, that all, -R4, -R5, -R6and the oxygens of the glycerol backbone in a glycerol ester alkoxylate molecule of the formula (I), may be connected to a [(C2H4)O]-group, they may all be connected to a [(CsHejOj-group or they may be connected independently from one another to either group selected from [(C2H4)O] and [(C3H6)O].

[0027] In a preferred embodiment of the invention, the structural units -[R1O]-, -[R2O]- and -[R3O]- in the mixture of glycerol ester alkoxylates of the formula (I) are [(C2H4)O].

[0028] The variables x, y, and z are the same or different and are independently integer numbers for each single glycerol ester alkoxylate molecule of the formula (I) in the mixture according to the invention and may be the same or different for the various glycerol ester alkoxylate molecules in the mixture according to the invention. The sum x+y+z is an integer number for each single glycerol ester alkoxylate molecule of the formula (I) in the mixture according to the invention and may be the same or different for the various glycerol ester alkoxylate molecules in the mixture according to the invention.

[0029] The sum x+y+z is, based on a molar average, a number equal to or greater than 95, preferably from 95 to 500, more preferably from 95 to 450 and even more preferably from 95 to 350, as for example 100 to 340. In a preferred embodiment, the lower limit for the sum x+y+z is 100 instead of 95.

[0030] Preferably, x, y, and z are the same or different and are each independently selected from integer numbers from 1 to 350, even more preferably from 2 to 300, particularly preferably from 5 to 250, extraordinarily preferably from 10 to 220, especially preferably from 15 to 210 and extremely preferably from 20 to 200.

[0031] In a preferred embodiment of the invention, in the mixtures of glycerol ester alkoxylates of the formula (I) for the inventive aqueous coating compositions, at least 20 mol%, preferably at least 25 mol%, more preferably at least 30 mol%, even more preferably at least 35 mol% and particularly preferably at least 40 mol% of those groups R4, R5and R6, which have a meaning different from hydrogen, are linear or branched, preferably linear, unsaturated acyl groups comprising 16 to 20 carbon atoms or mixtures thereof and preferably are linear or branched, preferably linear, unsaturated acyl groups comprising 16 to 18 carbon atoms or mixtures thereof, in each case based on the total amount of the acyl groups R4, R5and R6.

[0032] In a further preferred embodiment of the invention, in the mixtures of glycerol ester alkoxylates of the formula (I) for the inventive aqueous coating compositions, the groups R4, R5and R6are selected from hydrogen and acyl groups derived from palm oil, rape seed oil, sunflower oil, high oleic sunflower oil, or mixtures thereof.

[0033] In the context of the present invention, “high oleic sunflower oil” refers to a sunflower oil, wherein the amount of the oleic acid residues in the oil, based on the total amount of fatty acid residues in the oil, is at least 50 mol%, preferably at least 60 mol%, more preferably at least 70 mol% and even more preferably at least 80 mol%.

[0034] In case the mixture of glycerol ester alkoxylates of the formula (I) comprises acyl groups with 16 carbon atoms and acyl groups with 18 carbon atoms, the molar ratio of the acyl groups with 16 carbon atoms to the acyl groups with 18 carbon atoms preferably is not 1 :1.

[0035] In case the mixture of glycerol ester alkoxylates of the formula (I) comprises saturated and unsaturated acyl groups with 16 carbon atoms and saturated and unsaturated acyl groups with 18 carbon atoms, the molar ratio of the sum of the saturated and unsaturated acyl groups with 16 carbon atoms to the sum of the saturated and unsaturated acyl groups with 18 carbon atoms preferably is <1 .0 and more preferably <0.9.

[0036] In case the mixture of glycerol ester alkoxylates of the formula (I) comprises saturated acyl groups with 16 carbon atoms and saturated acyl groups with 18 carbon atoms, the molar ratio of the saturated acyl groups with 16 carbon atoms to the saturated acyl groups with 18 carbon atoms preferably is >1 .0, more preferably >1 .2 and even more preferably >1 .5.

[0037] In case the mixture of glycerol ester alkoxylates of the formula (I) comprises saturated and unsaturated acyl groups with 16 carbon atoms and saturated acyl groups with 18 carbon atoms, the molar ratio of the sum of the saturated and unsaturated acyl groups with 16 carbon atoms to the saturated acyl groups with 18 carbon atoms preferably is >1.0, more preferably >1.2 and even more preferably >1.5.

[0038] In case the mixture of glycerol ester alkoxylates of the formula (I) comprises acyl groups with 16 carbon atoms and acyl groups with 18 carbon atoms, the weight ratio of the acyl groups with 16 carbon atoms to the acyl groups with 18 carbon atoms preferably is not 1 :1. In case the mixture of glycerol ester alkoxylates of the formula (I) comprises saturated and unsaturated acyl groups with 16 carbon atoms and saturated and unsaturated acyl groups with 18 carbon atoms, the weight ratio of the sum of the saturated and unsaturated acyl groups with 16 carbon atoms to the sum of the saturated and unsaturated acyl groups with 18 carbon atoms preferably is <1 .0 and more preferably <0.9.

[0039] In case the mixture of glycerol ester alkoxylates of the formula (I) comprises saturated acyl groups with 16 carbon atoms and saturated acyl groups with 18 carbon atoms, the weight ratio of the saturated acyl groups with 16 carbon atoms to the saturated acyl groups with 18 carbon atoms preferably is >1 .0, more preferably >1 .2 and even more preferably >1 .5.

[0040] In case the mixture of glycerol ester alkoxylates of the formula (I) comprises saturated and unsaturated acyl groups with 16 carbon atoms and saturated acyl groups with 18 carbon atoms, the weight ratio of the sum of the saturated and unsaturated acyl groups with 16 carbon atoms to the saturated acyl groups with 18 carbon atoms preferably is >1.0, more preferably >1.2 and even more preferably >1.5.

[0041] Glycerol ester alkoxylates are already known in the prior art. Glycerol ester ethoxylates of the prior art are e. g. described in WO 2020 / 239750 A1 , WO 2020 / 239760 A1 , WO 2021 / 078807 A1 , EP 4 067 468 A1 , WO 2023 / 057335 A1 or WO 2023 / 083995 A1 .

[0042] Glycerol ester alkoxylates may be produced by the reaction of glycerol ester such as triglyceride with alkylene oxide e.g. using catalysts based on calcium or magnesium.

[0043] An alternative route to prepare glycerol ester alkoxylates is a transesterification reaction of a methyl ester or esterification reaction of a carboxylic acid with an alkoxylated glycerol. The mixtures of glycerol ester alkoxylates of the formula (I) for the inventive aqueous coating compositions, may advantageously be prepared by alkoxylation of glycerol esters such as triglycerides using an alkaline earth metal catalyst.

[0044] The mixture of glycerol ester alkoxylates of the formula (I) wherein

[0045] R1, R2, R3, x, y, z, R4, R5, R6, and the sum of x+y+z, are as defined above, and the amount of the glycerol ester alkoxylates of the formula (I), wherein all of the groups R4, R5and R6have a meaning different from hydrogen, is as defined above, can be prepared from ethylene oxide, propylene oxide or a mixture of ethylene oxide and propylene oxide and a mixture of glycerol esters of the formula (II) wherein R4, R5and R6in the mixture of the glycerol esters of the formula (II) have the same meaning as in the mixture of the glycerol ester alkoxylates of the formula (I) and in the single glycerol ester molecules of the formula (II), not all of the groups R4, R5and R6are simultaneously hydrogen, characterized in that in the method a catalyst (C) based on an alkaline earth metal is used.

[0046] In the method for preparing a mixture of glycerol ester alkoxylates of the formula (I) for the inventive aqueous coating compositions, R4, R5and R6in the mixture of the glycerol esters of the formula (II) have the same meaning as in the mixture of the glycerol ester alkoxylates of the formula (I).

[0047] This e.g. means, that

[0048] R4, R5and R6in the mixture of the glycerol esters of the formula (II), are, independent from each other, selected from hydrogen and linear or branched, preferably linear, saturated or unsaturated acyl groups comprising from 8 to 30 carbon atoms or mixtures thereof, and at least 70 mol% of the glycerol esters of the formula (II) in the mixture of the glycerol esters of the formula (II), based on the total amount of the glycerol esters of the formula (II) in the mixture of the glycerol esters of the formula (II), are glycerol esters of the formula (II), wherein all of the groups R4, R5and R6have a meaning different from hydrogen, and in the mixture of the glycerol esters of the formula (II), at least 30 mol% of those groups R4, R5and R6, which have a different meaning from hydrogen, are linear or branched, preferably linear, saturated or unsaturated acyl groups comprising 16 to 20 carbon atoms or mixtures thereof, based on the total amount of the linear or branched, preferably linear, saturated or unsaturated acyl groups R4, R5and R6.

[0049] Preferably, triglycerides of the formula (II) are used for the preparation of mixtures of alkoxylates of the formula (I) and are not admixed with other reactants that contain any free hydroxyl groups.

[0050] Preferably, in the method, the catalyst (C) is obtainable by a reaction involving

[0051] (a) an alkaline earth metal compound (A) and

[0052] (b) one or more substances selected from the group consisting of a carboxylic acid (B) preferably comprising 3 to 60, more preferably 3 to 46, carbon atoms; a polyalkylene glycol having a molecular weight from 100 g / mol to 1500 g / mol; a C1-C18 alkyl-capped polyalkylene glycol having a molecular weight from 100 g / mol to 1500 g / mol; an alcohol solvent; and mixtures including any of the foregoing, and

[0053] (c) a strong acid (AC).

[0054] The carboxylic acid (B) mentioned under component (b) above may e. g. be a carboxylic acid, wherein the carboxylic acid function -COOH is connected to a hydrocarbon group but may also e. g. be a carboxylic acid wherein the carboxylic acid function -COOH is connected to a hydrocarbon group that contains or is interrupted by ether functions.

[0055] The alcohol mentioned in component (b) is an alcohol wherein the hydroxyl function -OH is bonded to a hydrocarbyl group.

[0056] Preferably, the alcohol solvent is an alcohol having 1 to 5 carbon atoms, more preferably propan-2-ol, or a mixture thereof with water.

[0057] Preferably, the alkaline earth metal compound (A) is selected from the group consisting of magnesium hydroxide, magnesium acetate, magnesium carbonate, magnesium sulfate, magnesium phosphate, calcium hydroxide, calcium acetate, calcium carbonate, calcium sulfate, calcium phosphate, strontium hydroxide, strontium acetate, strontium carbonate, strontium sulfate, strontium phosphate, barium hydroxide, barium acetate, barium carbonate, barium sulfate, and barium phosphate. In a more preferred embodiment of the method, the alkaline earth metal compound (A) is selected from the group consisting of calcium hydroxide, calcium acetate, calcium carbonate, calcium sulfate, and calcium phosphate. In another more preferred embodiment of the method, the alkaline earth metal compound (A) is selected from the group consisting of magnesium hydroxide, magnesium acetate, calcium hydroxide, calcium acetate, strontium hydroxide, strontium acetate, barium hydroxide, and barium acetate. Particularly preferably, in the method the alkaline earth metal compound (A) is selected from the group consisting of calcium acetate and calcium hydroxide. Preferably, the strong acid (AC) is an acid which has a PKA value of 3 or less, more preferably is selected from the group consisting of acids of sulfur oxides and phosphorus oxides, even more preferably from the group consisting of sulfuric acid, sulfurous acid, sulfonic acids (among the sulfonic acids methane sulfonic acid is preferred), phosphorus acid, phosphorous acid and phosphonic acids (among the phosphonic acids methane phosphonic acid is preferred) and particularly preferably from the group consisting of sulfuric acid, sulfurous acid and methane sulfonic acid. Extraordinarily preferably, the strong acid (AC) is sulfuric acid.

[0058] Preferably, the molar ratio of the alkaline earth metal compound (A) to the strong acid (AC) is from 1 .0:0.1 to 1.0:1 .0, more preferably from 1.0:0.2 to 1 .0:0.9 and even more preferably from 1.0:0.3 to 1.0:0.8.

[0059] Preferably, the polyalkylene glycol having a molecular weight from 100 g / mol to 1500 g / mol is a polyethylene glycol having a molecular weight from 100 g / mol to 1500 g / mol.

[0060] Preferably, the C1-C18 alkyl-capped polyalkylene glycol having a molecular weight from 100 g / mol to 1500 g / mol is a methyl-capped polyalkylene glycol having a molecular weight from 100 g / mol to 1500 g / mol and more preferably is a methyl- capped polyethylene glycol having a molecular weight from 100 g / mol to 1500 g / mol.

[0061] Preferably, volatile components are removed before the catalyst (C) is used for the preparation of the mixture of glycerol ester alkoxylates of the formula (I).

[0062] In one preferred embodiment of the method a carboxylic acid (B) is used in the preparation of the catalyst (C).

[0063] Preferably, the molar ratio of alkaline earth metal compound (A) to carboxylic acid (B) in the preparation of the catalyst (C) is from 1 :1 to 1 :5.

[0064] Preferably, the carboxylic acid (B) is represented by formula (III),

[0065] R4-[O]q-[CH2CH2-O]P-CH2COOH (HI) wherein

[0066] R4is selected from saturated or unsaturated, linear or branched Ci to C30 hydrocarbyl groups, preferably Ci to C22 hydrocarbyl groups, and more preferably Ce to Cis hydrocarbyl groups, q is 0 or 1 , and p is, based on molar average, a number from 0 to 11 , preferably from 1 to 11 , more preferably from 1 to 9, and even more preferably from 2 to 7.

[0067] In a more preferred embodiment the carboxylic acid (B) is represented by formula (HI),

[0068] R4-[O]q-[CH2CH2-O]P-CH2COOH (III) wherein R4is selected from saturated or unsaturated, linear or branched Ci to C30 hydrocarbyl groups, preferably Ci to C22 hydrocarbyl groups, and more preferably Ce to Cis hydrocarbyl groups, q is 0, and p is 0, and preferably is isononanoic acid or oleic acid.

[0069] In another more preferred embodiment the carboxylic acid (B) is represented by formula (III),

[0070] R4-[O]q-[CH2CH2-O]P-CH2COOH (III) wherein R4is selected from saturated or unsaturated, linear or branched Ci to C30 hydrocarbyl groups, preferably Ci to C22 hydrocarbyl groups, and more preferably Ce to C18 hydrocarbyl groups, q is 1 , and p is, based on molar average, a number from 0 to 11 , preferably from 1 to 11 , more preferably from 1 to 9, and even more preferably from 2 to 7, and preferably, R4is oleyl, q is 1 , and p is, based on molar average, 5.

[0071] In one preferred embodiment the catalyst (C) is obtainable by a reaction involving (a) calcium hydroxide and

[0072] (b) a carboxylic acid (B), which is represented by formula (III),

[0073] R4-[O]q-[CH2CH2-O]P-CH2COOH (III) wherein R4is selected from saturated or unsaturated, linear or branched Ci to C30 hydrocarbyl groups, preferably Ci to C22 hydrocarbyl groups, and more preferably Ce to Cis hydrocarbyl groups, q is 0, and

[0074] P is 0, and preferably is isononanoic acid, and an alcohol solvent, preferably an alcohol solvent having 1 to 5 carbon atoms, more preferably propan-2-ol, or a mixture thereof with water, and

[0075] (c) sulfuric acid.

[0076] In another preferred embodiment the catalyst (C) is obtainable by a reaction involving

[0077] (a) calcium hydroxide and

[0078] (b) a carboxylic acid (B), which is represented by formula (III),

[0079] R4-[O]q-[CH2CH2-O]P-CH2COOH (III) wherein R4is selected from saturated or unsaturated, linear or branched Ci to C30 hydrocarbyl groups, preferably Ci to C22 hydrocarbyl groups, and more preferably Ce to Cis hydrocarbyl groups, q is 1 , and p is, based on molar average, a number from 0 to 11 , preferably from 1 to 11 , more preferably from 1 to 9, and even more preferably from 2 to 7, and preferably, R4is oleyl, q is 1 , and p is, based on molar average, 5, and an alcohol solvent, preferably an alcohol solvent having 1 to 5 carbon atoms, more preferably propan-2-ol, or a mixture thereof with water, and

[0080] (c) a strong acid and preferably sulfuric acid. In another preferred embodiment the catalyst (C) is obtainable by a reaction involving

[0081] (a) calcium acetate and

[0082] (b) a polyalkylene glycol having a molecular weight from 100 g / mol to 1500 g / mol or mixtures of such polyalkylene glycols, and

[0083] (c) sulfuric acid.

[0084] In another preferred embodiment the catalyst (C) is obtainable by a reaction involving

[0085] (a) calcium acetate and

[0086] (b) a carboxylic acid (B), which is represented by formula (III),

[0087] R4-[O]q-[CH2CH2-O]P-CH2COOH (III) wherein R4is selected from saturated or unsaturated, linear or branched Ci to C30 hydrocarbyl groups, preferably Ci to C22 hydrocarbyl groups, and more preferably Ce to Cis hydrocarbyl groups, q is 0, and p is 0, and preferably, is oleic acid, and a C1-C18 alkyl-capped polyalkylene glycol having a molecular weight from 100 g / mol to 1500 g / mol, preferably a methyl-capped polyalkylene glycol having a molecular weight from 100 g / mol to 1500 g / mol and more preferably a methyl- capped polyethylene glycol having a molecular weight from 100 g / mol to 1500 g / mol or mixtures of such alkyl-capped polyalkylene glycols, and

[0088] (c) sulfuric acid.

[0089] In another preferred embodiment the catalyst (C) is obtainable by a reaction involving

[0090] (a) calcium acetate and

[0091] (b) an alcohol solvent, preferably an alcohol solvent having 1 to 5 carbon atoms, more preferably propan-2-ol, or a mixture thereof with water, and

[0092] (c) sulfuric acid. In the method for preparing the mixture of alkoxylates of the formula (I), the molar ratio of the alkylene oxide selected from the group consisting of ethylene oxide, propylene oxide and mixtures of ethylene oxide and propylene oxide to the one or more glycerol esters of the formula (II) preferably is from 20:1 to 300:1 , more preferably from 50:1 to 300:1 , even more preferably from 80:1 to 250:1 , and particularly preferably from 90:1 to 250:1 .

[0093] The molar ratio of alkaline earth metal compound (A) to carboxylic acid (B) (molar ratio (A):(B)) in the preparation of the catalyst (C) preferably is from 1 :1 to 1 :5. More preferably, the molar ratio (A):(B) is from 1 :1.5 to 1 :4, even more preferably from 1 : 1.8 to 1 :2.2 and particularly preferably from 1 : 1 .9 to 1 :2.1. In an extraordinarily preferred embodiment of the invention, the molar ratio of (A):(B) in the preparation of the catalyst (C) is approximately 1 :2.

[0094] In one preferred embodiment the reaction for the preparation of the catalyst (C) is carried out in the presence of at least one polar solvent, more preferably a polar solvent comprising at least one hydroxyl group, even more preferably at least one alcohol having 1 to 5 carbon atoms or a mixture thereof with water. In a particularly preferred embodiment, the polar solvent is propan-2-ol or a mixture thereof with water. In another particularly preferred embodiment, the polar solvent is ethanol or a mixture thereof with water.

[0095] It is advisable to perform the reaction for obtaining the catalyst (C) in the presence of an acid (AC) which has a PKA value of 3 or less, preferably 2 or less, more preferably 0 or less, and often -3 or less.

[0096] Preferably, the acid (AC) is selected from the group consisting of acids of sulfur oxides and phosphorus oxides, more preferably from the group consisting of sulfuric acid, sulfurous acid, sulfonic acids (among the sulfonic acids methane sulfonic acid is preferred), phosphorus acid, phosphorous acid and phosphonic acids (among the phosphonic acids methane phosphonic acid is preferred). Sulfuric acid, sulfurous acid and methane sulfonic acid are of particular interest. In a particularly preferred embodiment the reaction for obtaining the catalyst (C) is performed in the presence of sulfuric acid.

[0097] It is particularly advantageous to prepare the alkaline earth metal catalyst (C) by first allowing the alkaline earth metal compound (A) to react with the carboxylic acid (B), preferably in a solvent as described above, after which the reaction mixture is further treated with the acid (AC).

[0098] It is also particularly advantageous to prepare the alkaline earth metal catalyst (C) by first dispersing the alkaline earth metal compound (A) in a polyalkylene glycol having a molecular weight from 100 g / mol to 1500 g / mol or mixtures of such polyalkylene glycols, or in a C1-C18 alkyl-capped polyalkylene glycol having a molecular weight from 100 g / mol to 1500 g / mol, preferably a methyl-capped polyalkylene glycol having a molecular weight from 100 g / mol to 1500 g / mol and more preferably a methyl- capped polyethylene glycol having a molecular weight from 100 g / mol to 1500 g / mol or mixtures of such alkyl-capped polyalkylene glycols, optionally in the presence of water, after which the reaction mixture is further treated with the acid (AC). The dispersing step may be performed in the presence of a carboxylic acid (B), which is represented by formula (III),

[0099] R4-[O]q-[CH2CH2-O]P-CH2COOH (III) wherein

[0100] R4is selected from saturated or unsaturated, linear or branched Ci to C30 hydrocarbyl groups, preferably Ci to C22 hydrocarbyl groups, and more preferably Ce to C18 hydrocarbyl groups, q is 0, and p is 0, and preferably is oleic acid.

[0101] It is also particularly advantageous to prepare the alkaline earth metal catalyst (C) by first dispersing the alkaline earth metal compound (A) in an alcohol solvent, preferably an alcohol solvent having 1 to 5 carbon atoms, more preferably propan-2- ol, or a mixture thereof with water, after which the reaction mixture is further treated with the acid (AC). For the reaction by which the alkaline earth metal catalyst (C) is obtained, any common reactor may be employed, preferably a reactor with an agitating / mixing means, such as, e.g., a magnetic stirrer, a mechanical stirrer, a static mixer, a blender, a batch disperser, or a Rotor-Stator disperser.

[0102] The preparation of the catalyst (C) is preferably carried out under a pressure of from 0.5 to 2 bar, more preferably from 0.8 to 1 .5 bar, even more preferably from 0.9 to 1.2 bar. In a preferred embodiment of the invention, the catalyst is prepared under atmospheric pressure. Furthermore, the catalyst (C) is preferably prepared at a temperature of from -30 °C to 80 °C, preferably from -10 °C to 60 °C, more preferably from 0 °C to 50 °C. In a preferred embodiment of the invention, the catalyst is prepared at a temperature of from 20 to 40 °C, especially at room temperature.

[0103] The thus prepared alkaline earth metal catalyst (C), preferably the calcium catalyst, typically has a content of alkaline earth metal ions, preferably Ca2+ions, that is from 0.5 to 10 wt.-%, often from 1 to 7 wt.-%, often from 2.0 to 5.5 wt.-%.

[0104] Optionally, the catalyst may be purged of volatile components, such as the solvent, water and other volatile byproducts by employing commonly used methods. Preferably, the volatile components are removed in vacuo, e.g. under a pressure below 0.8 bar, preferably below 0.3 bar, more preferably below 0.1 bar, and / or at elevated temperatures, e.g. 50 to 180 °C, preferably 70 to 150 °C, more preferably 80 to 140 °C.

[0105] In a particularly preferred embodiment of the invention, the volatile compounds are removed on a rotary evaporator at a pressure below 0.1 bar and a temperature of from 80 °C to 140 °C.

[0106] Preferably, the method for preparing a mixture of glycerol ester alkoxylates of the formula (I) according to the invention comprises the steps of i) introducing the catalyst (C) as defined above and one or more glycerol esters of the formula (II) as described above into a pressure-resistant reactor; ii) optionally replacing the air in the reactor with nitrogen or other protective gas; iii) optionally drying the reactor content at a temperature of from 50 to 200 °C and / or a pressure below 0.8 bar; iv) heating the content of the reactor to a temperature of from 80 °C to 200 °C; v) optionally pressurizing the reactor with nitrogen or other protective gas to a pressure of from 0.3 bar to 3.5 bar above atmospheric pressure; vi) pressurizing the reactor with alkylene oxide gas selected from the group consisting of ethylene oxide gas, propylene oxide gas and mixtures of ethylene oxide gas and propylene oxide gas to a pressure of from 1 .5 bar to 10 bar above atmospheric pressure with the proviso that the pressure is above the pressure prior to step vi); vii) allowing the mixture to react until the pressure in the reactor is constant.

[0107] In step i), the catalyst (C) may be introduced as obtained from the reaction of its preparation described above directly, or in its form that has been purged of volatile compounds, but preferably as obtained from the reaction of its preparation described above directly. The glycerol esters of formula (II) may be introduced in their raw form or may be purified prior to use.

[0108] The catalyst (C) is preferably introduced into the reactor in an amount from 0.5 to 5 wt.-%, preferably from 1 to 3 wt.-%, more preferably from 1 to 2 wt.-% based on the total weight of the mixture of glycerol esters of formula (II) and alkylene oxide selected from the group consisting of ethylene oxide, propylene oxide and mixtures of ethylene oxide and propylene oxide.

[0109] The pressure-resistant reactor is not particularly limited but is designed to withstand the pressures employed in the process, thus that it is not damaged during the process. Preferably, the reactor is designed to withstand pressures both above 10 bar, more preferably above 15 bar, and below 0.01 bar, more preferably below 0.001 bar. Preferably, the pressure-resistant reactor is an autoclave, more preferably an autoclave equipped with an agitating means such as a magnetic or a mechanical stirrer. Generally, the replacement of air in the reactor with nitrogen or other protective gas is not necessarily required, because the mixture of glycerol ester alkoxylates of the formula (I) according to the invention would at least partially be generated in the process. However, air, particularly oxygen, in the reactor may lead to safety concerns during alkoxylation reactions in general and decomposition products due to oxidation and / or hydrolysis of the employed materials and of the generated products, especially at elevated temperatures. Therefore, it is advisable to carry out step ii) of the method of the invention after step i).

[0110] In general, the step of drying the reactor content is also not necessarily required, because the mixture of glycerol ester alkoxylates of the formula (I) according to the invention would at least partially be generated in the process. However, water and alcohols may facilitate hydrolysis and transesterification of the employed materials and of the generated products under the reaction conditions. Especially if in step i) the catalyst (C) is introduced into the reactor as obtained from the reaction of its preparation described above directly, it is advisable to carry out the drying step, since the directly obtained catalyst (C) typically contains residues of polar solvents or their mixtures with water. In case the catalyst (C) is purged of volatile components before introducing it into the reactor, the drying step iii) may be omitted. Nevertheless, in this case it may be advisable to carry out step iii) since volatile components may also be present as impurities in the one or more glycerol esters of formula (II). Therefore, in particularly preferred embodiments, step iii) is carried out.

[0111] The step iii) of drying the reactor content is typically performed at a temperature of from 50 °C to 200 °C, preferably of from 50 °C to 180 °C, more preferably of from 60 °C to 150 °C, even more preferably of from 70 °C to 130 °C, particularly preferably of from 80 °C to 120 °C, and at a pressure below 0.8 bar, preferably below 0.1 bar, more preferably below 0.05 bar. The thus generated vacuum is preferably a dynamic vacuum.

[0112] The vacuum pump for generating the vacuum is not particularly limited; it is, however, preferable to use an aspirator for generating the vacuum. Furthermore, it is advisable to reduce the pressure and increase temperature in the reactor gradually to prevent boiling retardation. In a particularly preferred embodiment, the step of drying the reactor content is carried out at a temperature of from 80 °C to 120 °C and a pressure below 0.01 bar, preferably over a period of at least 15 minutes, more preferably over a period of at least 30 minutes, even more preferably over a period of at least 1 hour. It is particularly preferred to dry the content of the reactor to constant mass.

[0113] After the drying step iii), the fluid line between the vacuum pump and the reactor is interrupted, to ensure that the components added to the reactor after the drying remain in the reactor and are not directly withdrawn therefrom. Furthermore, it is preferable to compensate the vacuum in the reactor with nitrogen or other protective gas before carrying out the further steps, to reduce the risk of air entering the reactor.

[0114] Step iv) of heating the content of the reactor is generally performed at a temperature of from 80 °C to 200 °C, preferably from 120 °C to 190 °C, more preferably from 160 °C to 180 °C. This temperature is maintained at least until step vi) is finished, preferably until step vii) is finished.

[0115] After setting the temperature in step iv), the reactor may be optionally pressurized in step v) with nitrogen or other protective gas to a pressure of from 0.3 to 3.5 bar, preferably of from 0.4 to 3.3 bar, more preferably of from 0.5 to 3.0 bar, even more preferably of from 0.7 to 2.5 bar and particularly preferably of from 0.8 to 2.2 bar above atmospheric pressure. By carrying out this step v), alkylene oxide selected from the group consisting of ethylene oxide, propylene oxide and mixtures of ethylene oxide and propylene oxide introduced in the following step is diluted with the protective gas, thus that pressure-controlled dosage of alkylene oxide into the reactor is facilitated.

[0116] In step vi) the reactor is further pressurized with alkylene oxide selected from the group consisting of ethylene oxide, propylene oxide and mixtures of ethylene oxide and propylene oxide to a total internal pressure of from 1 .5 to 10 bar, preferably from 2 to 8 bar, more preferably from 3 to 6 bar, even more preferably from 4 to 5 bar, above atmospheric pressure, with the proviso that the pressure in step vi) is above the pressure before step vi). During step vii), after introduction of the intended amount of alkylene oxide selected from the group consisting of ethylene oxide, propylene oxide and mixtures of ethylene oxide and propylene oxide, the alkylene oxide inlet is closed and the reaction is allowed to proceed until the pressure in the reactor is constant.

[0117] In the sense of the invention, the pressure is considered constant, if it does not change by more than 0.05 bar over a period of 15 minutes, preferably 30 minutes, more preferably 1 hour. It is particularly preferred that the pressure in the reactor does not change by more than 0.01 bar over a period of 1 hour.

[0118] After completion of step vii), it is advisable to remove residual alkylene oxide from the reactor before isolating the mixture of glycerol ester alkoxylates of the formula (I) according to the invention, in order to prevent any unwanted reactions with alkylene oxide from taking place after isolation of the product. Preferably, residual alkylene oxide is removed from the reactor by cooling the reactor content to a temperature of from 50 to 120 °C, more preferably from 70 to 100 °C and even more preferably from 85 to 95 °C, and employing a pressure of below 0.8 bar, preferably below 0.1 bar, more preferably below 0.05 bar. The thus generated vacuum is preferably a dynamic vacuum. The vacuum pump for generating the vacuum is not particularly limited; it is, however, preferable to use an aspirator for generating the vacuum. Removal of residual alkylene oxide under these conditions is preferably carried out for at least 10 minutes, more preferably at least 30 minutes and even more preferably at least 1 hour.

[0119] The method of isolation of the mixture of glycerol ester alkoxylates of the formula (I) according to the invention is not particularly limited. However, it is preferable to isolate the product at elevated temperatures, specifically at temperatures of from 50 to 150 °C, preferably from 60 to 140 °C, more preferably from 80 to 120 °C. At these temperatures, the mixture of glycerol ester alkoxylates of the formula (I) according to the invention is typically in a liquid state and has a sufficiently low viscosity, and therefore may be transferred out of the reactor more easily than in the solid state, e.g. by pouring the product out of the reactor or via a bottom valve, thereby minimizing the amount of residues in the reactor. Thus, the subsequent cleaning and maintenance of the reactor is also facilitated. The method for preparing a mixture of glycerol ester alkoxylates of the formula (I) according to the invention using the catalyst (C) described above may be interrupted at any stage, and continued at a later point in time, without the reaction time being significantly increased.

[0120] The mixture of glycerol ester alkoxylates of the formula (I) according to the invention may occur together with starting material used for its preparation, in particular glycerol ester in case the inventive mixture is prepared by alkoxylation of glycerol esters (in the following referred to as “composition A”). In case glycerol ester is present in the compositions A, the glycerol ester may be present in an amount of 0.1 wt.-% or more, or 0.25 wt.-% or more, or 0.5 wt.-% or more, or 1 .0 wt.-% or more, in each case based on the total weight of the composition A. In case glycerol ester is present in the compositions A, the glycerol ester is present in an amount of preferably less than 20.0 wt.-%, more preferably less than 10.0 wt.-%, even more preferably less than 5.0 wt.-%, particularly preferably less than 2.0 wt.-% and extraordinarily preferably less than 1 .0 wt.-%, in each case based on the total weight of the composition A.

[0121] During the preparation of the mixture according to the invention, by-products may be formed. The formation of by-products in chemical reactions is quite normal since these reactions usually do not take place with a selectivity of 100 %. However, in case by-products are formed during the preparation of the mixture according to the invention, these by-products are formed in an amount of preferably less than 25.0 wt.-%, more preferably less than 20.0 wt.-%, even more preferably less than 15.0 wt.-%, particularly preferably less than 10.0 wt.-%, extraordinarily preferably less than 6.0 wt.-% and especially preferably less than 5.0 wt.-%, in each case based on the combined total weight of the mixture according to the invention and the byproducts, and in particular in case the inventive mixture is prepared by a method according to the invention.

[0122] Starting material, and in particular glycerol ester, occurring together with the mixture according to the invention is considered to form part of the by-products. Furthermore, the mixture according to the invention may be purified after its preparation and prior to its use, e.g. by distilling, stripping or filtering-off by-products, but in a preferred embodiment, the mixture may be used as obtained without prior purification.

[0123] A further subject matter of the invention is an alkoxylation product obtainable by the inventive method described above for preparing a mixture according to the invention. The alkoxylation product comprises a mixture of glycerol ester alkoxylates of the formula (I) according to the invention and may optionally comprise further substances such as starting materials or reactants, in particular glycerol esters of the formula (II), and / or by-products.

[0124] The inventive mixtures of glycerol ester alkoxylates of the formula (I) or the inventive alkoxylation product may also be bio-based.

[0125] Bio-based glycerol ester alkoxylates of formula (I) can, for example, be prepared from (i) glycerol esters of the formula (II) such as triglycerides and (ii) ethylene oxide, propylene oxide or mixtures of ethylene oxide and propylene oxide, wherein at least a part of one of the aforementioned alkylene oxides is bio-based.

[0126] Bio-based ethylene oxide can be obtained from bio-ethanol, which can be obtained from natural sources like com, sugarcane, or cellulosic biomass through fermentation. Bio-ethanol is then dehydrated to produce bio-ethylene. The bioethylene is then oxidized with oxygen over a silver catalyst to produce bio-based ethylene oxide.

[0127] Bio-based propylene oxide can be obtained from

[0128] 1 ) bio-glycerol, which can be obtained from biodiesel production, hydrolysis of vegetable oils, or fermentation of sugars. Bio-glycerol is then converted to acrolein via dehydration. Acrolein is hydrogenated to produce bio-propanol and subsequently dehydrated to provide bio-propylene, which is epoxidized to produce propylene oxide using hydrogen peroxide; or

[0129] 2) bio-ethanol, which can be obtained from natural sources like com, sugarcane, or cellulosic biomass through fermentation. Bio-ethanol is then dehydrated to produce bio-ethylene. The bio-ethylene is then catalytically dimerized to biobutene. Bio-butene and bio-ethylene are then converted to bio-propylene via metathesis. The bio-propylene is then catalytically converted to propylene oxide.

[0130] Preferably, the materials used to prepare the inventive mixture of glycerol ester alkoxylates of the formula (I) or the inventive alkoxylation product are bio-based and derived from natural sources. More preferably, the inventive mixture of glycerol ester alkoxylates of the formula (I) or the inventive alkoxylation product has at least 25 wt.-%, preferably at least 50 wt.-%, more preferably at least 75 wt.-%, even more preferably at least 90 wt.-% and particularly preferably 100 wt.-% bio-based carbon content, in each case relative to the total mass of carbon in the mixture of alkoxylates of the formula (I) or relative to the total mass of carbon in the alkoxylation product, respectively.

[0131] Preferably, the hydroxyl number of the alkoxylation product according to the invention is smaller than 15 mg KOH / g, more preferably smaller than 10 mg KOH / g and even more preferably smaller than 5 mg KOH / g. The hydroxyl number is measured according to DIN EN ISO 4629-2.

[0132] The inventive coating composition comprises a binder. The binder is the film-forming component of a paint or coating composition, the vehicle that carries the pigment and further constituents, and then dries or cures, holding it in place. The binder is also responsible for adhesion, durability, flexibility, gloss, and other physical properties. A binder is a necessary component of any paint or coating composition. Depending on the type of paint or coating, pigments solvents, fillers or other paint or coating additives may be added.

[0133] A distinction between organic and inorganic binders is made.

[0134] Organic binders.

[0135] Suitable organic binders are polymeric binders which are usually the product of the emulsion polymerization olefinically unsaturated monomers. Organic binders are usually polymers of olefi nically unsaturated monomers. Examples of olefinically unsaturated monomers are: vinyl monomers, such as carboxylic esters of vinyl alcohol, as for example vinyl acetate, vinyl propionate, vinyl ethers of isononanoic acid or isodecanoic acid, which are also referred to as C9 and C10-versatic acids,

[0136] Aryl-substituted olefins, such as styrene and stilbene, olefinically unsaturated carboxylic esters such as methyl acrylate, ethyl acrylate, propyl acrylate, n-butyl acrylate, i-butyl acrylate, pentyl acrylate, hexyl acrylate, 2- ethylhexyl acrylate, tridecyl acrylate, stearyl acrylate, hydroxyethyl acrylate, hydroxypropyl acrylate and the corresponding methacrylic esters, olefinically unsaturated dicarboxylic esters, such as dimethyl maleate, diethyl maleate, dipropyl maleate, dibutyl maleate, dipentyl maleate, dihexyl maleate and di-2-ethylhexyl maleate, olefinically unsaturated carboxylic acids and dicarboxylic acids, such as acrylic acid, methacrylic acid, itaconic acid, maleic acid and fumaric acid and their sodium, potassium and ammonium salts, olefinically unsaturated sulfonic acids and phosphonic acids and their alkali and ammonium salts, such as vinylsulfonic acid, vinylphosphonic acid, acrylamidomethylpropanesulfonic acid and its alkali and ammonium, alkylammonium and hydroxyalkylammonium salts, allylsulfonic acid and its alkali and ammonium salts, acryloyloxethylphosphonic acid and its ammonium and alkali salts and the corresponding methacrylic acid derivatives, olefinically unsaturated amines, ammonium salts, nitriles and amides, such as dimethylaminoethyl acrylate, acryloyloxethyltrimethylammonium halide, acrylonitrile, acrylamide, methacrylamide, N-methylacrylamide, N-ethylacrylamide, N- propylacrylamide, N-methylolacrylamide as well as the corresponding methacrylic acid derivatives and vinylmethylacetamide.

[0137] Inorganic binders Suitable inorganic binders are water-soluble silicates of alkali metals like sodium, potassium or lithium.

[0138] Coating compositions also generally contain pigments, whereby the term “pigments” refers to both pigments and fillers in the broader sense, and auxiliary substances. Auxiliary substances can include wetting and dispersing agents, defoamers, biocides, coalescing agents, further rheology modifiers and pH-adjustment agents.

[0139] Suitable pigments are finely divided, organic or inorganic white or colored pigments or a mixture of various such pigments.

[0140] An example of a selection of particularly preferred organic pigments are carbon blacks, monoazo and disazo pigments, in particular the color index pigments Pigment Yellow 1 , Pigment Yellow 3, Pigment Yellow 12, Pigment Yellow 13, Pigment Yellow 14, Pigment Yellow 16, Pigment Yellow 17, Pigment Yellow 73, Pigment Yellow 74, Pigment Yellow 81 , Pigment Yellow 83, Pigment Yellow 87, Pigment Yellow 97, Pigment Yellow 111 , Pigment Yellow 126, Pigment Yellow 127, Pigment Yellow 128, Pigment Yellow 155, Pigment Yellow 174, Pigment Yellow 176, Pigment Yellow 191 , Pigment Yellow 213, Pigment Yellow 214, Pigment Red 38, Pigment Red 144, Pigment Red 214, Pigment Red 242, Pigment Red 262, Pigment Red 266, Pigment Red 269, Pigment Red 274, Pigment Orange 13, Pigment Orange 34 or Pigment Brown 41 ; [3-naphthol and naphthol AS pigments, in particular the color index pigments Pigment Red 2, Pigment Red 3, Pigment Red 4, Pigment Red 5, Pigment Red 9, Pigment Red 12, Pigment Red 14, Pigment Red 53:1 , Pigment Red 112, Pigment Red 146, Pigment Red 147, Pigment Red 170, Pigment Red 184, Pigment Red 187, Pigment Red 188, Pigment Red 210 , Pigment Red 247, Pigment Red 253, Pigment Red 254, Pigment Red 256, Pigment Orange 5, Pigment Orange 38 or Pigment Brown 1 ; lake azo and metal complex pigments, in particular the color index pigments Pigment Red 48:2, Pigment Red 48:3, Pigment Red 48:4, Pigment Red 57:1 , Pigment Red 257, Pigment Orange 68 or Pigment Orange 70; benzimidazolone pigments, in particular the color index pigments Pigment Yellow 120, Pigment Yellow 151 , Pigment Yellow 154, Pigment Yellow 175, Pigment Yellow 180, Pigment Yellow 181 , Pigment Yellow 194, Pigment Red 175, Pigment Red 176, Pigment Red 185, Pigment Red 208, Pigment Violet 32, Pigment Orange 36, Pigment Orange 62, Pigment Orange 72 or Pigment Brown 25; isoindolinone and isoindoline pigments, in particular the color index pigments Pigment Yellow 139 or Pigment Yellow 173; phthalocyanine pigments, in particular the color index pigments Pigment Blue 15, Pigment Blue 15:1 , Pigment Blue 15:2, Pigment Blue 15:3, Pigment Blue 15:4, Pigment Blue 15:6, Pigment Blue 16, Pigment Green 7 or Pigment Green 36; anthanthrone, anthraquinone, quinacridone, dioxazine, indanthrone, perylene, perinone- and thioindigo pigments, in particular the color index pigments Pigment Yellow 196, Pigment Red 122, Pigment Red 149, Pigment Red 168, Pigment Red 177, Pigment Red 179, Pigment Red 181 , Pigment Red 207, Pigment Red 209, Pigment Red 263, Pigment Blue 60, Pigment Violet 19, Pigment Violet 23 or Pigment Orange 43; triarylcarbonium pigments, in particular the color index pigments Pigment Red 169, Pigment Blue 56 or Pigment Blue 61 ; diketopyrrolopyrrole pigments, especially the color index pigments Pgment Red 254, Pigment Red 255, Pigment Red 264, Pigment Red 270, Pigment Red 272, Pigment Orange 71 , Pigment Orange 73 or Orange 81 .

[0141] Suitable inorganic pigments are, for example, titanium dioxide, zinc sulfides, zinc oxides, iron oxides, magnetites, manganese iron oxides, chromium oxides, ultramarine, nickel or chromium antimony titanium oxides, manganese titanium rutiles, cobalt oxides, mixed oxides of cobalt and aluminium, rutile mixed phase pigments, rare earth sulfides, spinels of cobalt with nickel and zinc, spinels based on iron and chromium with copper, zinc and manganese, bismuth vanadates and extender pigments, in particular the color index pigments Pigment Yellow 184, Pigment Yellow 53, Pigment Yellow 42, Pigment Yellow Brown 24, Pigment Red 101 , Pigment Blue 28, Pigment Blue 36, Pigment Green 50, Pigment Green 17, Pigment Black 11 , Pigment Black 33 and Pigment White 6 are used; Calcium carbonates also known as fillers such as naturally occurring chalk and precipitated calcium carbonate, dolomite, natural silicon dioxide (quartz flour), pyrogenic and precipitated silica, diatomaceous earth, aluminum oxides, aluminum hydroxides, talc, kaolin, mica (potassium aluminum silicate hydrate), barium sulfates such as naturally occurring barite and precipitated Blanc Fix.

[0142] Mixtures of inorganic pigments are also often preferred. Mixtures of organic and inorganic pigments are also frequently used.

[0143] Suitable wetting and dispersing agents are preferentially homopolymers and copolymers of acrylic acid, methacrylic acid, maleic acid, fumaric acid and the sodium, potassium and ammonium salts thereof; polyphosphonates and phosphonic acid derivatives; alkylphenolethoxylates, such as Guerbet derivatives, fatty acid and fatty alcohol derivatives, especially the ethoxylation prooducts; ethylene oxide / propylene oxide homo- and block-copolymers and polysiloxane ethers.

[0144] Suitable defoamers are preferably mineral oil defoamers and their emulsions, silicone oil defoamers and silicone oil emulsions, silicone resins, polyalkylene glycols, polyalkylene glycol fatty esters, fatty acids, fatty acid salts of divalent and trivalent cations such as aluminium stearate, higher alcohols, phosphoric acid esters, hydrophobically modified silica, polyethylene waxes and amide waxes such as ethylenebissterarylamide.

[0145] Suitable biocides to prevent the uncontrolled proliferation of bacteria, algae and fungi are formaldehyde, formaldehyde-releasing compounds, methylisothiazolinone, chloromethylisothiazolinone, benzisothiazolinone, bronopol, dibromodicyanonebutane and silver chloride-coated titanium dioxide.

[0146] Suitable coalescing agents are esters and ketones such as benzoates and butyrates, as well as ether alcohols and glycols.

[0147] In particular, 2,2,4-trimethyl-pentane-1 ,3-diol mono-isobutyrate, butyl glycol, butyl diglycol, butyldipropylene glycol, propylene glycol butyl ether and dipropylene glycol butyl ether are mentioned as coalescing agents.

[0148] Preferably, rheology modifiers are starch and cellulose derivatives, hydrophobically modified ethoxylated urethane (HELIR) thickeners, alkali-swellable acrylate thickeners and their hydrophobically modified counterparts, xanthans, layered silicates, polymers of acrylamidomethylpropanesulfonic acid and pyrogenic silica. Suitable pH-adjusting agents are alkali metal hydroxides of mono-, di- or trivalent metal ions or ammonium hydroxide or organic amines. Preferred are sodium hydroxide or potassium hydroxide and their aqueous solutions. Among the organic amines, 2-amino-2-methyl-1 -propanol, N-methyl-D-glucamine and N,N-dimethyl-D- glucamine are specially preferred.

[0149] An overview of common additives is provided by Wernfried Heilen et al. in “Additive fur wassrige Lacksysteme”, published by Vincentz Network, 2009.

[0150] In the inventive aqueous coating compositions, the mixture of glycerol ester alkoxylates of the formula (I) is used in an amount of 0.01 to 10 wt.%, preferably in an amount from 0.05 to 5 wt.-%, more preferably in an amount from 0.1 to 3 wt.%, based on the weight of the aqueous coating composition.

[0151] References to the aqueous coating composition refer to its composition prior to application and drying.

[0152] The glycerol ester alkoxylates of the formula (I) can be introduced in the coating compositions as solid or as an aqueous composition, the aqueous composition preferably containing the glycerol ester alkoxylates of formula (I) in an amount from 1 to 90 wt.-%, more preferably in an amount from 2 to 85 wt.-% and even more preferably in an amount from 5 to 80 wt.-%, in each case based on the total weight of the aqueous compositions. Said aqueous compositions may comprise one or more solvents. Suitable solvents are, propylene glycol methyl ether, propylene glycol methyl ether acetate, dipropylene glycol methyl ether, propylene glycol n-propyl ether, dipropylene glycol n-butyl ether, dipropylene glycol n-propyl ether, dipropylene glycol dimethyl ether, butyl triglycol, ethylene glycol n-butyl ether, propylene glycol diacetate, dipropylene glycol dimethyl ether, preferably in a ratio with water (water: solvent) from 1 :10 to 10:1 , They are liquid solutions or liquid dispersions at one atmosphere (1 atm = 101325 Pascal), preferably above 60 °C, more preferably above 50 °C, even more preferably above 45 °C, particularly preferably above 40 °C and extraordinarily preferably above 20 °C. Using the the glycerol ester alkoxylates of formula (I) in form of an aqueous composition has been found to have a positive impact on syneresis (examples table 3).

[0153] Examples The examples below are intended to illustrate the invention in detail without, however, limiting it thereto. Percentages in this description are percentages by weight based on the weight of the total composition, unless otherwise stated.

[0154] In the following tables the numbers of EO units refer to the sum x+y+z in formula (I). Thickening efficiency: In a comparative series, aqueous lacquers were prepared according to the composition given in table 1 and were investigated with regard to their effectivity as rheology modifiers.

[0155] To produce the lacquer, components 1 and 2 were homogenized at 100 to 300 rpm using a Getzmann dissolver with a sawtooth stirrer. Subsequently, components 3-7 were added successively at high shear rate (1000-1300 rpm) and dispersed or homogenized. Finally, the lacquer was deaerated in a speed-mixer.

[0156] Table 1 : Composition of aqueous lacquers in weight%

[0157] Viscosity was measured using a Haake viscosimeter iQ (Thermofischer) and a coaxial cylinder geometry in rotation mode. The measurements were done as follows: the shear rate was increased from 0 s-1to 500 s-1linearly during 120 seconds at 23 °C.

[0158] The utilization of ethoxylated sunflower oil with 100 EO allows a significant reduction in the required amount of rheology modifier, achieving the same viscosity curve as ethoxylated sunflower oil with 45 EO (Figure 1 ). Specifically, less than half the quantity of rheology modifier is needed when using the 100 EO variant.

[0159] Additionally, comparative analysis demonstrates that ethoxylated sunflower oil with 100 EO exhibits superior efficacy in increasing viscosity at low shear rates compared to its 80 EO counterpart, when used in equal amounts (Figure 2).

[0160] Sagging resistance:

[0161] In a comparative series, aqueous lacquers were prepared according to the composition given in table 2 and were investigated with regard to their effect on sagging.

[0162] To produce the lacquer, components 1 and 2 were homogenized at 100 to 300 rpm using a Getzmann dissolver with a sawtooth stirrer.

[0163] Subsequently, components 3-7 were added successively at high shear rate (1000- 1300 rpm) and dispersed or homogenized.

[0164] Finally, the lacquer was deaerated in a speed-mixer.

[0165] The sagging resistance test was performed as follows:

[0166] The coatings were applied onto a horizontally positioned contrast card using a sag index applicator at a rate of 15 mm / s. The sag index applicator deposits 10 film stripes of varying layer thicknesses onto the surface. Immediately after application, the coated contrast card was positioned vertically with the thickest layer facing downwards. The evaluation determines the maximum coating layer thickness that does not sag into the adjacent stripe during the vertical drying process. A higher maximum thickness indicates superior sagging resistance of the coating formulation. Table 2: Composition of aqueous lacquers in weight%

[0167] Tendency to syneresis:

[0168] In a comparative series, aqueous lacquers were prepared according to the composition given in table 3 and were investigated with regard to their tendency to form syneresis.

[0169] To produce the lacquer, components 1 and 3 were homogenized by successive addition at 100 to 300 rpm using a Getzmann dissolver with a sawtooth stirrer. Subsequently, components 4-8 were added successively at high shear rate (1000- 1300 rpm) and dispersed or homogenized.

[0170] The tendency to syneresis was evaluated as follows:

[0171] A 100 mL glass vessel was filled with the lacquer up to 3 / 4 of its volume. The lacquer was then subjected to an accelerated aging test by storing it at 50°C for 28 days. Subsequently, the extent of syneresis was quantified by measuring the height of the clear serum layer formed at the top in millimetres. A lower measured value of syneresis indicates a superior storage stability.

[0172] 37 Table 3: Composition of aqueous lacquers in weight%

[0173] Water resistance:

[0174] In a comparative series, clear aqueous lacquers were prepared according to the composition given in Table 4 and were investigated with regard to their water resistance.

[0175] To produce the clear lacquer, components 1-3 were homogenized by successive addition at 100 to 300 rpm using a Getzmann dissolver with a sawtooth stirrer.

[0176] Subsequently, components 4-6 were added successively and homogenized at high shear rate (1000-1300 rpm) for 1 minute. Finally, component 7 was added and the mixture was homogenized at high rate (1000-1300 rpm) for 1 minute. The lacquer was then deaerated in a speed-mixer.

[0177] Water resistance was proofed as follows: The clear lacquer was applied by means of a wire bar applicator (300 pm) to a glass plate. After drying, 2 hours at room temperature and 2 hours at 50 °C, water droplets were set on the coating and after a given period of time removed by softly pressing with a paper tissue. It iss noted the longest period of time until a damage in the coating is perceived. The longer the time the better.

[0178] Table 4: Composition of aqueous lacquers in weight%

Claims

Patent Claims1 . An aqueous coating composition comprising a) a binder b) mixtures of glycerol ester alkoxylates selected from the substances of the following formula (I)whereinR1, R2and R3are, independent from each other, selected from linear or branched alkylene groups (CmH2m) with m being 2 or 3 or mixtures thereof; x, y and z are, independently from each other, integer numbers from 0 to400, where at least one of the variables x, y and z is 1 or an integer number greater than 1 , and preferably integer numbers from 1 to 350, more preferably from 5 to 250;R4, R5and R6are, independent from each other, selected from hydrogen and linear or branched, preferably linear, saturated or unsaturated acyl groups comprising from 8 to 30 carbon atoms or mixtures thereof, preferably are, independent from each other, selected from hydrogen and linear or branched, preferably linear, saturated or unsaturated acyl groups comprising from 12 to 30 carbon atoms or mixtures thereof,more preferably are, independent from each other, selected from hydrogen and linear or branched, preferably linear, saturated or unsaturated acyl groups comprising from 12 to 24 carbon atoms or mixtures thereof, even more preferably are, independent from each other, selected from hydrogen and linear or branched, preferably linear, saturated or unsaturated acyl groups comprising from 12 to 20 carbon atoms or mixtures thereof, and particularly preferably are, independent from each other, selected from hydrogen and linear or branched, preferably linear, saturated or unsaturated acyl groups comprising from 14 to 20 carbon atoms or mixtures thereof, and wherein in the definitions of R4, R5and R6above, at least one of R4, R5and R6has a meaning different from hydrogen; characterized in that x+y+z is, based on a molar average, a number equal to or greater than95, preferably a number from 95 to 500, more preferably from 95 to 450, even more preferably from 95 to 350, at least 70 mol%, preferably at least 75 mol%, more preferably at least 80 mol% and even more preferably at least 85 mol% of the glycerol ester alkoxylates of the formula (I) in the mixture, in each case based on the total amount of the glycerol ester alkoxylates of the formula (I) in the mixture, are glycerol ester alkoxylates of the formula (I), wherein all of the groups R4, R5and R6have a meaning different from hydrogen; and at least 30 mol%, preferably at least 40 mol%, more preferably at least 50 mol%, even more preferably at least 60 mol% and particularly preferably at least 70 mol% of those groups R4, R5and R6, which have a meaning different from hydrogen, are linear or branched, preferably linear, saturated or unsaturated acyl groups comprising 16 to 20 carbon atoms or mixtures thereof and preferably are linear or branched, preferably linear, saturated or unsaturated acyl groups comprising 16 to 18 carbonatoms or mixtures thereof, in each case based on the total amount of the linear or branched, preferably linear, saturated or unsaturated acyl groups R4, R5and R6, and c) water.

2. An aqueous coating composition according to claim 1 , wherein the alkoxylation product b) is obtained by alkoxylating a mixture of glycerol esters of the formula (II)wherein R4, R5and R6in the mixture of the glycerol esters of the formula (II) have the same meaning as in formula (I), with ethylene oxide, propylene oxide or a mixture of ethylene oxide and propylene oxide in the presence of a catalyst (C) based on an alkaline earth metal.

3. An aqueous coating composition according to claims 1 or 2, comprising 1 to 80 wt.% binder.

4. An aqueous coating composition according to one or more of claims 1 to 3, comprising 0.01 to 10 wt.% of a mixture of glycerol ester alkoxylates of the formula (I).

5. An aqueous coating composition according to one or more of claims 1 to 4, comprising 10-95 wt.% water.

6. An aqueous coating composition according to one or more of claims 1 to 5, wherein the binder is an organic polymeric binder.

7. An aqueous coating composition according to one or more of claims 1 to 6, wherein a defoamer is present.

8. An aqueous coating composition according to one or more of claims 1 to 7, wherein one or more pigments are present.

9. An aqueous coating composition according to one or more of claims 1 to 8, wherein one or more wetting or dispersing agents are present.

10. An aqueous coating composition according to one or more of claims 1 to 9, wherein a coalescing agent is present.

11. An aqueous coating composition according to one or more of claims 1 to 10, wherein biocides are present.

12. An aqueous coating composition according to one or more of claims 1 to 11 , wherein neutralising agents are present.

13. An aqueous coating composition according to one or more of claims 1 to 12 wherein rheology modifiers are present that differ from the of glycerol ester alkoxylates according to formula (I).

14. Use of mixture of glycerol ester alkoxylates selected from the substances of the following formula (I)whereinR1, R2and R3are, independent from each other, selected from linear or branched alkylene groups (CmH2m) with m being 2 or 3 or mixtures thereof; x, y and z are, independently from each other, integer numbers from0 to 400, where at least one of the variables x, y and z is 1 or an integer number greater than 1 , and preferably integer numbers from 1 to 350, more preferably from 5 to 250;R4, R5 and R6 are, independent from each other, selected from hydrogen and linear or branched, preferably linear, saturated or unsaturated acyl groups comprising from 8 to 30 carbon atoms or mixtures thereof, preferably are, independent from each other, selected from hydrogen and linear or branched, preferably linear, saturated or unsaturated acyl groups comprising from 12 to 30 carbon atoms or mixtures thereof, more preferably are, independent from each other, selected from hydrogen and linear or branched, preferably linear, saturated or unsaturated acyl groups comprising from 12 to 24 carbon atoms or mixtures thereof, even more preferably are, independent from each other, selected from hydrogen and linear or branched, preferably linear, saturated or unsaturated acyl groups comprising from 12 to 20 carbon atoms or mixtures thereof, and particularly preferably are, independent from each other, selected from hydrogen and linear or branched, preferably linear, saturated or unsaturated acyl groups comprising from 14 to 20 carbon atoms or mixtures thereof, and wherein in the definitions of R4, R5and R6above, at least one of R4, R5and R6has a meaning different from hydrogen;characterized in that x+y+z is, based on a molar average, a number equal to or greater than 95, preferably a number from 95 to 500, more preferably from 95 to 450, even more preferably from 95 to 350, at least 70 mol%, preferably at least 75 mol%, more preferably at least 80 mol% and even more preferably at least 85 mol% of the glycerol ester alkoxylates of the formula (I) in the mixture, in each case based on the total amount of the glycerol ester alkoxylates of the formula (I) in the mixture, are glycerol ester alkoxylates of the formula (I), wherein all of the groups R4, R5and R6have a meaning different from hydrogen; and at least 30 mol%, preferably at least 40 mol%, more preferably at least 50 mol%, even more preferably at least 60 mol% and particularly preferably at least 70 mol% of those groups R4, R5and R6, which have a meaning different from hydrogen, are linear or branched, preferably linear, saturated or unsaturated acyl groups comprising 16 to 20 carbon atoms or mixtures thereof and preferably are linear or branched, preferably linear, saturated or unsaturated acyl groups comprising 16 to 18 carbon atoms or mixtures thereof, in each case based on the total amount of the linear or branched, preferably linear, saturated or unsaturated acyl groups R4, R5and R6, and as rheology modifiers for aqueous coating compositions comprising a binder and water.

15. Process for modifying the rheology of a coating composition comprising a binder and water, the process comprising the step of adding to the water and a binder a mixture of glycerol ester alkoxylates selected from the substances of the following formula (I)whereinR1, R2and R3are, independent from each other, selected from linear or branched alkylene groups (CmH2m) with m being 2 or 3 or mixtures thereof; x, y and z are, independently from each other, integer numbers from0 to 400, where at least one of the variables x, y and z is 1 or an integer number greater than 1 , and preferably integer numbers from 1 to 350, more preferably from 5 to 250;R4, R5 and R6 are, independent from each other, selected from hydrogen and linear or branched, preferably linear, saturated or unsaturated acyl groups comprising from 8 to 30 carbon atoms or mixtures thereof, preferably are, independent from each other, selected from hydrogen and linear or branched, preferably linear, saturated or unsaturated acyl groups comprising from 12 to 30 carbon atoms or mixtures thereof, more preferably are, independent from each other, selected from hydrogen and linear or branched, preferably linear, saturated or unsaturated acyl groups comprising from 12 to 24 carbon atoms or mixtures thereof, even more preferably are, independent from each other, selected from hydrogen and linear or branched, preferablylinear, saturated or unsaturated acyl groups comprising from 12 to 20 carbon atoms or mixtures thereof, and particularly preferably are, independent from each other, selected from hydrogen and linear or branched, preferably linear, saturated or unsaturated acyl groups comprising from 14 to 20 carbon atoms or mixtures thereof, and wherein in the definitions of R4, R5and R6above, at least one of R4, R5and R6has a meaning different from hydrogen; characterized in that x+y+z is, based on a molar average, a number equal to or greater than 95, preferably a number from 95 to 500, more preferably from 95 to 450, even more preferably from 95 to 350, at least 70 mol%, preferably at least 75 mol%, more preferably at least 80 mol% and even more preferably at least 85 mol% of the glycerol ester alkoxylates of the formula (I) in the mixture, in each case based on the total amount of the glycerol ester alkoxylates of the formula (I) in the mixture, are glycerol ester alkoxylates of the formula (I), wherein all of the groups R4, R5and R6have a meaning different from hydrogen; and at least 30 mol%, preferably at least 40 mol%, more preferably at least 50 mol%, even more preferably at least 60 mol% and particularly preferably at least 70 mol% of those groups R4, R5and R6, which have a meaning different from hydrogen, are linear or branched, preferably linear, saturated or unsaturated acyl groups comprising 16 to 20 carbon atoms or mixtures thereof and preferably are linear or branched, preferably linear, saturated or unsaturated acyl groups comprising 16 to 18 carbon atoms or mixtures thereof, in each case based on the total amount of the linear or branched, preferably linear, saturated or unsaturated acyl groups R4, R5and R6.

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