Aqueous fire protection composition with high application layer thickness and fire protection coating with improved resistance to the formation of mould

Abstract

The invention relates to an aqueous fire protection composition with rapid hardening even with a high layer thickness, said fire protection composition containing a binder based on an aqueous polymer latex of a film-forming carboxylated polymer, a branched polyether amine polyol with substantially tertiary amino groups, and further relates to a fire protection coating produced from the aqueous fire protection composition and having improved resistance to the formation of mould. The invention also relates to the use of the fire protection composition for fire protection, in particular for coatings of components, such as pillars, beams and truss members.

Description

[0001] Water-based fire protection composition with high application layer thickness and fire protection coating with improved resistance to mold growth

[0002] DESCRIPTION

[0003] The present invention relates to an aqueous fire protection composition with rapid curing even in high layer thicknesses, which contains a binder based on an aqueous polymer latex of a film-forming carboxylated polymer, a branched polyetheramine polyol with essentially tertiary amino groups, and a fire protection coating produced from the aqueous fire protection composition with improved resistance to mold growth. The invention further relates to the use of the fire protection composition for fire protection, in particular for coatings of structural components such as columns, beams, or trusses.

[0004] Intumescent compounds are typically applied to the surface of building components to form coatings to protect them from fire or against excessive heat, such as those resulting from a fire. Steel structures have become an integral part of modern architecture, even though they have one significant disadvantage compared to reinforced concrete construction. Above approximately 500°C, the load-bearing capacity of steel drops by 50%, meaning the steel loses its stability and load-bearing capacity. Depending on the fire load, such as direct fire exposure (approximately 1000°C), this temperature can be reached after just 5-10 minutes, which often leads to a loss of load-bearing capacity of the structure.The objective of fire protection, particularly steel fire protection, is to delay the time until a steel structure loses its load-bearing capacity in the event of a fire for as long as possible in order to save human lives and valuable goods.

[0005] The building codes of many countries stipulate corresponding fire resistance periods for certain steel structures. These are defined by so-called F classes such as F 30, F 60, F 90, F 120, and F 180 (fire resistance classes according to DIN 4102-2) or American classes according to ASTM, etc. According to DIN 4102-2, for example, F 30 means that a load-bearing steel structure must withstand fire for at least 30 minutes in the event of a fire under standard conditions. This is usually achieved by slowing the heating rate of the steel, e.g., by coating the steel structure with intumescent coatings. These coatings are coatings whose components expand in the event of a fire, forming a solid, microporous carbon foam.This creates a thick, fine-pored foam layer, the so-called ash crust, which, depending on its composition, has strong thermal insulation properties and thus delays the heating of the component, so that the critical temperature of approximately 500°C is reached after 30, 60, 90, 120, 180 minutes, or up to 240 minutes at the earliest. The achievable fire resistance always depends on the applied layer thickness of the coating, or rather, the resulting ash crust. Closed profiles, such as pipes, require approximately twice the amount of foam compared to open profiles, such as beams with a double-T profile, for comparable solidity. To ensure compliance with the required fire resistance times, the coatings must have a certain thickness and be able to form the most voluminous and thus well-insulating ash crust possible when exposed to heat, which remains mechanically stable throughout the fire exposure period.

[0006] Various systems already exist for this purpose, with a large proportion of the products available on the market being based on water-based dispersions.

[0007] Patent WO 2019 / 099372 A1 describes aqueous coating compositions based on polymeric binders with at least one coalescing agent and one or more additives from the group of intumescent additives, anti-vibration additives, and sound-decoupling additives. The polymeric binder is provided in a first component and the coagulant in a second component. The additive(s) can be present in the first component, the second component, or both the first and second components. Upon direct or simultaneous application of the two components to a substrate to be coated, a coating is formed within 30 seconds of application that is adhesive, stable, water-resistant, and non-tacky (dry).

[0008] In publicly accessible facilities such as sports stadiums, skyscrapers, airports, train stations or administrative buildings, but also in private areas, an aesthetic top coat is increasingly being dispensed with, among other things for cost reasons, so that fire protection coatings must increasingly also meet aesthetic aspects and therefore have to have good to very good surface properties.

[0009] The compositions disclosed in WO 2019 / 099372 A1 exhibit rapid curing with respect to intumescent coatings and allow for high coating thicknesses. However, the corresponding compositions exhibit disadvantages with regard to the stability of the ash crust in the event of a fire and with regard to their surface quality. To improve the stability of the ash crust in the event of a fire, the proportion of intumescent additives in the composition is usually increased, and more than 50 wt.% based on the total weight of the composition is usually used. However, the resulting high solids content leads to an increase in the surface roughness of the resulting cured coating with increasing solids content, especially when the composition was applied by hand or spray. As the surface roughness increases, the gloss of the cured coating decreases.For the purposes of the present invention, the combination of surface roughness and gloss is collectively referred to as a surface property. Low surface roughness and high gloss therefore correspond to very good surface properties.

[0010] The application of the fire protection coating as a two-component system (A+B) disclosed in WO 2019 / 099372 A1 entails several disadvantages. For example, the handling of two-component spray equipment on construction sites is generally complex, and therefore users prefer single-component solutions. Furthermore, the separation of the binder composition and coagulant in the two individual aqueous components leads to an increased water content in the combined mixture.

[0011] This leads to extended drying times, even if the binder composition itself cures very quickly. Binder compositions with the highest possible solids content and the lowest possible water content are advantageous.

[0012] Furthermore, the compositions described in WO 2019 / 099372 A1 also exhibit disadvantages with regard to their storage stability, and the compositions themselves, as well as the coatings produced from them, have low resistance to mold growth, since the partially water-soluble carbon source necessarily contained in the composition represents a good food source for microorganisms. However, these properties are essential for intumescent coating compositions, both to guarantee customers transport and storage options and to ensure the long-term functionality of the coating.

[0013] There is a need for a composition that demonstrates good processability despite a high solids content of 50 wt.% and more based on the total weight of the composition. The coating produced from the composition should also exhibit good fire resistance and good to very good surface properties, particularly low surface roughness and attractive gloss properties. Furthermore, there is a need for an aqueous fire protection composition and a fire protection coating that exhibits very low susceptibility to mold growth.

[0014] It is therefore an object of the present invention to provide an aqueous fire protection composition that overcomes the disadvantages of the prior art. In particular, there is a need for aqueous fire protection compositions that offer sufficiently rapid curing even with high layer thicknesses in order to provide sufficient functional layer thicknesses with as few work steps as possible. Furthermore, it is an object of the present invention to improve the resistance of the aqueous fire protection composition itself and of the coating produced from the fire protection composition to mold formation. The object underlying the invention is achieved by an aqueous fire protection composition according to claim 1. Advantageous embodiments emerge from the subclaims, which can be optionally combined with one another.

[0015] The object underlying the invention is achieved by an aqueous fire protection composition comprising a polymer as an aqueous binder, which

[0016] (a) an aqueous polymer latex of a film-forming carboxylated polymer;

[0017] (b) 0.05 to 7.5 wt.%, based on the dry weight of the carboxylated polymer, of a branched polyetheramine polyol, dissolved in the aqueous phase of the polymer latex, wherein at least 90% of all amino groups in the branched polyetheramine polyol are tertiary amine groups, and wherein the aqueous polymer latex of the carboxylated polymer is obtainable by a free-radical emulsion polymerization of a monomer composition M, wherein the monomer composition M comprises, i) 70 wt.% to 99.95 wt.-%, based on the total weight of the monomer composition M, of one or more ethylenically unsaturated monomers M1 which are selected from Ci-C2o-alkyl esters of monoethylenically unsaturated monocarboxylic acids having 3 to 6 carbon atoms, di-Ci-C2o-alkyl esters of monoethylenically unsaturated dicarboxylic acids having 4 to 6 C atoms, Cs-C2o-cycloalkyl esters of monoethylenically unsaturated monocarboxylic acids having 3 to 6 C atoms, vinyl esters of Ci-C2o-alkanoic acids, vinyl aromatic monomers, C2-C6 monoolefins and butadiene; ii) 0.05 wt.% to 10 wt.%, based on the total weight of the monomer composition M, of one or more monoethylenically unsaturated monomers M2 selected from monoethylenically unsaturated monocarboxylic acids having 3 to 6 carbon atoms and monoethylenically unsaturated dicarboxylic acids having 4 to 6 carbon atoms; iii) 0 wt.% to 20 wt.-%, based on the total weight of the monomer composition M, of one or more non-ionic monomers M3 which are different from the monomers M1, at least one intumescent fire protection additive and at least one compound for improving microorganism resistance.

[0018] Advantageous embodiments arise from the subclaims, which can optionally be combined with one another.

[0019] A further aspect of the present invention relates to the use of the aqueous fire protection composition as a fire protection coating, in particular intumescent fire protection coating.

[0020] Yet another aspect of the present invention relates to a method for producing a coating on a surface, comprising applying the fire protection composition as defined herein to the surface and allowing the composition to cure to produce the coating.

[0021] For a better understanding of the invention, the following explanations of the terminology used herein are considered useful. For the purposes of the invention: "chemical intumescence" means the formation of a voluminous, insulating ash layer by matched compounds that react with each other when exposed to heat; "physical intumescence" means the formation of a voluminous, insulating layer by the expansion of a compound which, without a chemical reaction having taken place between two compounds, releases gases when exposed to heat, causing the volume of the compound to increase many times its original volume; "insulating layer forming" or "intumescent effect" means that in the event of a fire, a solid, microporous carbon foam is formed, so that the fine-pored and thick foam layer formed, the so-called ash crust, insulates a substrate against heat, depending on its composition;a “carbon supplier” is an organic compound which leaves behind a carbon framework through incomplete combustion and does not burn completely to carbon dioxide and water (carbonification); these compounds are also referred to as “carbon framework formers”; a “dehydrogenation catalyst” is a compound which, when exposed to heat, i.e. above approximately 150°C, for example through decomposition, forms a non-volatile acid and thereby acts as a catalyst for carbonification; it can also contribute to reducing the viscosity of the melt of the binder; the term “dehydrogenation catalyst” is used synonymously here; a “blowing agent” is a compound which decomposes at elevated temperatures with the development of inert, i.e. non-flammable gases and expands the carbon framework formed by the carbonification and possibly the softened binder into a foam (intumescence);this term is used synonymously with “gas former”; an “ash crust stabilizer” is a so-called framework-forming compound that stabilizes the carbon framework (ash crust) formed from the interaction of carbon formation from the carbon source and the gas from the propellant, or physical intumescence. The basic mode of operation is that the inherently very soft carbon layers that are formed are mechanically strengthened by inorganic compounds. The addition of such an ash crust stabilizer contributes to a significant stabilization of the intumescent crust in the event of a fire, as these additives increase the mechanical strength of the intumescent layer and / or prevent it from dripping, thereby maintaining or enhancing the insulating effect of the foam. indicate the prefixes “C; n -C m,” which are used in connection with compounds or molecular units, each indicate a range for the number of possible carbon atoms that a molecular unit or compound can have. denotes "Ci-C n -AlkylT refers to a group of linear or branched saturated hydrocarbon radicals having 1 to n carbon atoms. For example, the term Ci-C2o-alkyl refers to a group of linear or branched saturated hydrocarbon radicals having 1 to 20 carbon atoms. Similarly, the term Cs-C2o-alkyl refers to a group of linear or branched saturated hydrocarbon radicals having 5 to 20 carbon atoms, while the term Ci-C4-alkyl refers to a group of linear or branched saturated hydrocarbon radicals having 1 to 4 carbon atoms. Examples of

[0022] Alkyl schließen Methyl, Ethyl, n-Propyl, Isopropyl, n-Butyl, 2-Butyl, 2-Methylpropyl (Isopropyl), 1,1 -Dimethylethyl (tert.-Butyl), Pentyl, 1-Methylbutyl ein, sind aber nicht darauf beschränkt, 2-Methylbutyl, 3-Methylbutyl, 2,2-Dimethylpropyl, 1 -Ethylpropyl, 1 ,1- Dimethylpropyl, 1,2-Dimethylpropyl, 1 -Methylpentyl, 2- Methylpentyl, 3- Methylpentyl, 4- Methylpentyl, 1,1 -Dimethylbutyl, 1,2-Dimethylbutyl, 1,3-

[0023] Dimethylbutyl, 2,2-dimethylbutyl, 2,3-dimethylbutyl, 3,3-dimethylbutyl, 1-ethylbutyl, 2-ethylbutyl, 1,1,2-trimethylpropyl, 1,2,2-trimethylpropyl, 1-ethyl-1-methylpropyl, 1-ethyl-2-methylpropyl, hexyl, heptyl, octyl, 2-ethylhexyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, octadecyl, nonadecyl, eicosyl, heneicosyl, docosyl and their isomers. C1-C4 alkyl means, for example, methyl, ethyl, propyl, 1-methylethyl, butyl, 1-methylpropyl, 2-methylpropyl or 1,1-dimethylethyl. The term "(meth)acrylic" includes both acrylic and methacrylic groups. Therefore, the term "(meth)acrylate" includes acrylate and methacrylate. The terms "polymer latex" and "polymer dispersion" are used synonymously and mean an aqueous polymer composition of a water-insoluble polymer, the polymer being in the form of finely dispersed polymer particles.Typically, the polymer latex is obtained by emulsion polymerization (also called primary latex), but it can also be obtained by emulsifying a polymer in an aqueous phase (secondary latex). The term "polyetheramine polyol" refers to a polymer containing amine groups, ether groups, and hydroxyl groups. The term "pphm" is short for "parts per hundred monomers" and is the weight percentage based on the total weight of monomers in the respective compound.

[0024] Composition. The range "x to y wt%" is a synonym for the range "x wt% to y wt%." Likewise, the range "x to y mol%" is a synonym for the range "x mol% to y mol%." For clarification, this also applies to ranges expressed in "mol / kg," "mg KOH / g," "g / mol," "pphm," "°C," and the like.

[0025] One object of the invention is an aqueous fire protection composition comprising a polymer as an aqueous binder, which

[0026] (a) an aqueous polymer latex of a film-forming carboxylated polymer;

[0027] (b) 0.05 to 7.5 wt.%, based on the dry weight of the carboxylated polymer, of a branched polyetheramine polyol, dissolved in the aqueous phase of the polymer latex, wherein at least 90% of all amino groups in the branched polyetheramine polyol are tertiary amine groups, and wherein the aqueous polymer latex of the carboxylated polymer is obtainable by a free-radical emulsion polymerization of a monomer composition M, wherein the monomer composition M comprises, i) 70 wt.% to 99.95 wt.-%, based on the total weight of the monomer composition M, of one or more ethylenically unsaturated monomers M1 which are selected from Ci-C2o-alkyl esters of monoethylenically unsaturated monocarboxylic acids having 3 to 6 carbon atoms, di-Ci-C2o-alkyl esters of monoethylenically unsaturated dicarboxylic acids having 4 to 6 C atoms, Cs-C2o-cycloalkyl esters of monoethylenically unsaturated monocarboxylic acids having 3 to 6 C atoms, vinyl esters of Ci-C2o-alkanoic acids, vinyl aromatic monomers, C2-C6 monoolefins and butadiene; ii) 0.05 wt.% to 10 wt.%, based on the total weight of the monomer composition M, of one or more monoethylenically unsaturated monomers M2 selected from monoethylenically unsaturated monocarboxylic acids having 3 to 6 carbon atoms and monoethylenically unsaturated dicarboxylic acids having 4 to 6 carbon atoms; iii) 0 wt.% to 20 wt.-%, based on the total weight of the monomer composition M, of one or more non-ionic monomers M3 which are different from the monomers M1, at least one intumescent fire protection additive and at least one compound for improving the resistance to microorganisms, wherein the proportion of the compound for improving the resistance to microorganisms is from 0.05 to 0.30 wt.%, based on the total weight of the aqueous fire protection composition.

[0028] Aqueous binder

[0029] In particular, it has been found that the branched polyetheramine polyols, as defined herein, reduce or eliminate the dependence of the drying properties of fire protection coatings based on aqueous polymer latexes of film-forming carboxylated polymers on the application temperature. Therefore, binders comprising a combination of a branched polyetheramine polyol, as defined herein, and an aqueous polymer latex of a film-forming carboxylated polymer can be used to produce fire protection compositions that exhibit drying behavior that is virtually independent of the application temperature and therefore offer accelerated drying at typical construction site temperatures. The fire protection composition according to the invention is further characterized by particularly rapid curing, even in high layer thicknesses.

[0030] A general disadvantage of such water-based systems, especially when used for fire protection coatings that require wet film thicknesses of 3 mm or more, is the purely physical drying of the coating compound.

[0031] The drying rate of a water-based fire protection coating, especially for structural shells, is highly dependent on the weather conditions, particularly the humidity, temperature, and wind speed during coating application. If the drying rate is too slow, for example, due to low temperature and / or high humidity, sudden rain can damage the coating. In addition, there may be an increased tendency to soil, which can then lead to reduced aesthetics. In contrast, a fast drying rate, for example, under elevated temperature and / or low humidity conditions, can lead to short open times, which can cause problems when applying the coating under these conditions. Therefore, there is a need to control the drying rate of a fire protection coating, which is less dependent on weather conditions.

[0032] A disadvantage of such physically curing fire protection compositions based on aqueous dispersions is their insufficient resistance to driving rain prior to curing. The term "precipitation" refers to heavy rain, whose droplets, depending on the droplet size and wind speed, can cause damage to the uncured coating composition in insufficiently cured surface areas.

[0033] Due to the faster curing achieved according to the invention, the required earlier driving rain resistance can be achieved and thus an intact coating can be ensured which nevertheless has sufficient water vapor permeability and thus allows the necessary drying over the entire layer thickness and thus results in a cured dry coating which ensures the desired fire protection and thus the essential requirements for the fire protection properties of the fire protection composition.

[0034] The aqueous fire protection composition according to the invention is particularly suitable for modifying the curing rate of the fire protection compositions.

[0035] Particularly advantageously, the fire protection composition according to the invention is adjusted to a pH value in the range from 7.5 to 9.0, preferably 8.0 to 8.5, with ammonia or an amino alcohol which is readily volatile at ambient temperature, such as ethanolamine.

[0036] The fire protection composition according to the invention is also stable over longer periods, such as more than 14 days, and does not tend to form agglomerates during storage.

[0037] The invention further relates to a coating made from the fire protection composition and a substrate coated with the coating.

[0038] According to the invention, the binder composition contains an aqueous polymer latex composed of a carboxylated polymer and at least one branched polyetheramine polyol. The branched polyetheramine polyol is dissolved in the aqueous phase of the polymer latex. Therefore, the polyetheramine polyol is water-soluble, at least to a certain extent.

[0039] Branched polyetheramine polyol

[0040] The water solubility of the branched polyetheramine polyol is preferably at least 5 g / l, more preferably at least 10 g / l, in particular at least 50 g / l, in particular 100 g / l, at 20°C.

[0041] In particular, the branched polyetheramine polyol is completely miscible with water at 20°C.

[0042] In the branched polyetheramine polyol dissolved in the aqueous phase of the polymer latex, substantially all of the amino groups are tertiary amine groups. In this context, the term "substantially" means that at least 90%, preferably at least 95%, more preferably more than 98%, and even more preferably more than 99% of the amino groups in the branched polyetheramine polyol are tertiary amine groups. In particular, the branched polyetheramine polyol has no detectable amounts of secondary and primary amino groups. Thus, in the branched polyetheramine polyol dissolved in the aqueous phase of the polymer latex, all of the amino groups in the branched polyetheramine polyol are tertiary amine groups. These are often branched.

[0043] Polyetheramine polyol contains, on average, less than 0.5 mol / kg of secondary and primary amino groups, if present. In particular, the polyetheramine polyol contains, on average, less than 0.2 mol / kg, in particular less than 0.1 mol / kg of secondary and primary amino groups, if present.

[0044] The branched polyetheramine polyol often contains an average of 4 to 8.2 mol / kg of tertiary amino groups. In particular, the polyetheramine polyol contains an average of 5 to 8.0 mol / kg of tertiary amino groups, especially 5 to 7.9 mol / kg.

[0045] The amine number of polyetheramine polyol is preferably in the range of 100 to 700 mg KOH / g, most preferably in the range of 200 to 500 mg KOH / g, determined according to the method described in DIN EN ISO 9702:1998. In addition to determining the total amine group content, this method allows the determination of the tertiary amine group content, the secondary amine group content, and the primary amine group content.

[0046] In addition to the amino groups, the polyetheramine polyol contains hydroxyl groups. The OH number of the polyetheramine polyol is often at least 100 mg KOH / g, e.g., 100 to 800 mg KOH / g, in particular at least 200 mg KOH / g, e.g., 200 to 700 mg KOH / g, in particular at least 250 mg KOH / g, e.g., 250 to 650 mg KOH / g, determined according to DIN 53240, Part 2. The number of hydroxyl groups per molecule depends on the number-average molecular weight of the branched polyetheramine polyol and the degree of branching. The branched polyetheramine polyol frequently contains on average (number average) at least four, particularly preferably at least six, and particularly preferably at least ten hydroxyl groups per molecule. The number of terminal or pendant functional groups is, in principle, unlimited. The branched polyetheramine polyol preferably contains on average (number average) at most 500, in particular at most 200 terminal hydroxyl groups per molecule.

[0047] The number-average molecular weight Mn of branched polyetheramine polyols is often in the range of 500 to 55,000 g / mol, in particular in the range of 1,000 to 40,000 g / mol, determined by gel permeation chromatography using hexafluoroisopropanol as the mobile phase and polymethyl methacrylate as the standard. The weight-average molecular weight Mw of polyetheramine polyols is often in the range of 1,000 to 300,000 g / mol, in particular in the range of 2,000 to 200,000 g / mol, and especially in the range of 5,000 to 150,000 g / mol, determined by gel permeation chromatography using hexafluoroisopropanol as the mobile phase and polymethyl methacrylate as the standard. The polydispersity, ie the ratio Mw / Mn, of the polyetheramine polyol is often in the range of 1.1 to 25, in particular in the range of 1.5 to 20.

[0048] The dynamic viscosity of the branched polyetheramine polyol is often in the range of 5 to 200 Pas, determined at 23°C according to ASTM D7042, and particularly in the range of 8 to 150 Pas. The term "branched" describes that the polyetheramine polyol does not have a linear structure, but has a significant number of branching points within the polymer main chain, resulting in a branched polymer chain. Such branching points can be tri- or tetrasubstituted carbon atoms and / or tertiary amino groups. The branching points are, in particular, the tertiary amino groups.

[0049] The Hazen color number of the polyetheramine polyol is preferably in the range of 100 to 600 (APHA), determined according to DIN ISO 6271.

[0050] The polyetheramine polyol is often amorphous and can therefore exhibit a glass transition. The glass transition temperature of the polyetheramine polyol preferably does not exceed 50°C, more preferably does not exceed 30°C, and even more preferably does not exceed 10°C, as determined by differential scanning calorimetry (DSC), as described below. The glass transition temperature of the polyetheramine polyol is preferably in the range of -55 to 30°C and more preferably in the range of -55 to 10°C, as determined by DSC.

[0051] Branched polyetheramine polyols and their preparation are known, for example from DE 3206459 A1, EP 441198 A2, WO 2009 / 047269 A2, WO 2014 / 012812 A1, which disclose branched polyetheramine polyols based on a polycondensation product of at least one trialkanolamine.

[0052] In one embodiment of the present invention, the branched polyetheramine polyol is obtainable by polycondensation of at least one trialkanolamine or by polycondensation of a mixture of at least one trialkanolamine with an aliphatic or cycloaliphatic polyol. Trialkanolamines for this purpose are preferably selected from tri-C2-C8 alkanolamines, where the alkanol groups in the trialkanolamine may be different or identical, with the alkanol groups preferably being identical. The trialkanolamines are particularly preferably selected from tri-C2-C4 alkanolamines, where the alkanol groups are identical.

[0053] Particularly preferred trialkanolamines are triethanolamine, tri-n-propanolamine, triisopropanolamine, tri-n-butanolamine and triisobutanolamine and mixtures thereof.

[0054] Suitable aliphatic or cycloaliphatic polyols include, for example, aliphatic diols, aliphatic polyols with more than two hydroxyl groups, cycloaliphatic diols, and cycloaliphatic polyols with more than two hydroxyl groups. Aliphatic diols and aliphatic polyols containing more than two hydroxyl groups are preferred. Examples of aliphatic diols are C2-C20 diols, such as ethanediol, propanediol, butanediol, pentanediol, hexanediol, heptanediol, octanediol, and their structural isomers. Further examples of aliphatic diols are polyether diols of the general formula HO-((CH2) n -O) m -H, where n is independently 1 to 10, preferably 2 to 4, and m is in the range of 2 to 100.

[0055] The polyether diols are preferably selected from polyethylene glycol, polypropylene glycol, polytetramethylene glycol, and copolymers thereof. Examples of polyols with more than two hydroxyl groups are glycerol, pentaerythritol, trimethylolpropane, sorbitol, and the like. The polyols can also be alkoxylated, especially ethoxylated or propoxylated, e.g., ethoxylated glycerol, propoxylated glycerol, ethylated pentaerythritol, propoxylated pentaerythritol, ethoxylated trimethylolpropane, propoxylated trimethylolpropane, ethoxylated sorbitol, and propoxylated sorbitol. Typically, the degree of alkoxylation, i.e., the number-average alkylene oxide content, will not exceed 100 and is frequently in the range of 2 to 50.

[0056] Preferably, the polyetheramine polyol is obtainable by polycondensation, wherein the monomers contain up to at least 50 wt.%, preferably at least 70 wt.%, particularly preferably at least 80 wt.%, based on the total amount of monomer, of compounds selected from trialkanolamines. The polyetheramine polyol is preferably obtainable by polycondensation of monomers containing 50 to 100 mol% of compounds selected from trialkanolamines and 0 to 50 mol% of compounds selected from aliphatic or cycloaliphatic polyols, preferably containing 70 to 100 mol% of compounds selected from trialkanolamines and 0 to 30 mol% of compounds selected from aliphatic or cycloaliphatic polyols, particularly preferably containing 80 to 100 mol% of compounds selected from trialkanolamines and 0 to 20 mol% of compounds selected from aliphatic or cycloaliphatic polyols, where “mol%” is based on the total amount of monomers.

[0057] In a particular embodiment, the polyetheramine polyol is obtainable by polycondensation, wherein the monomers consist only of monomers selected from trialkanolamines. The trialkanolamine is preferably selected from tri-C2-C4 alkanolamines. Preferred tri-C2-C4 alkanolamines are selected from triethanolamine, triisopropanolamine, and tri-n-propanolamine.

[0058] The mixture of at least one trialkanolamine with an aliphatic or cycloaliphatic polyol is preferably selected from mixtures of at least one trialkanolamine selected from the group consisting of tri-C2-C4 alkanolamines and an aliphatic or cycloaliphatic C2-C8 polyol.

[0059] Particularly preferably, polyetheramine polyols are obtainable by polycondensation of either triethanolamine or triisopropanolamine or a mixture of triethanolamine and triisopropanolamine. In this embodiment, at least one further polyol, in particular at least one further diol, may optionally be present.

[0060] The polycondensation can be carried out with or without the presence of a catalyst. Suitable catalysts include, but are not limited to, phosphoric acid (H3PO4), phosphorous acid (H3PO3), or hypophosphoric acid (H3PO2), which can be applied in bulk or as an aqueous solution. Preferably, the catalyst is added in an amount of 0.001 to 10 mol%, preferably 0.005 to 7 mol%, more preferably 0.01 to 5 mol%, based on the amount of trialkanolamine.

[0061] The polycondensation can be carried out using a solvent. Examples of solvents that can be used to carry out the process are aromatic and / or (cyclo)aliphatic hydrocarbons and their mixtures, halogenated hydrocarbons, ketones, esters, and ethers. Aromatic hydrocarbons, (cyclo)aliphatic hydrocarbons, alkyl esters of alkanoic acids, ketones, alkoxylated alkyl esters of alkanoic acids, and mixtures thereof are preferred. Particular preference is given to monoalkylated or polyalkylated benzenes and naphthalenes, ketones, alkyl esters of alkanoic acids and alkoxylated alkyl esters of alkanoic acids, and mixtures thereof. The polycondensation is preferably carried out without the use of a solvent.

[0062] The polycondensation can be carried out such that the temperature during the polycondensation does not exceed 250°C and preferably 230°C. For example, the polycondensation is carried out at temperatures in the range of 150 to 230°C, preferably 180 to 215°C. More preferably, the temperature during the polycondensation does not exceed 215°C and especially does not exceed 210°C.

[0063] The polycondensation can be carried out at a pressure in the range of 0.02 to 20 bar. Preferably, the polycondensation is carried out at atmospheric pressure. The polycondensation is preferably followed by removal or blowing off of residual monomers, for example by distillation at atmospheric pressure or at reduced pressure, for example, in the range of 0.1 to 0.5 bar.

[0064] Water or other volatile products released during polycondensation can be removed from the reaction mixture to accelerate the reaction. Preferably, water or other volatile products released during polycondensation are removed, for example, by distillation and optionally under reduced pressure. The removal of water or other low-molecular-weight reaction by-products can also be assisted by passing a gas stream that is largely inert under the reaction conditions (stripping), such as nitrogen or a noble gas such as helium, neon, or argon, through the reaction mixture.

[0065] The branched polyetheramine polyols described herein are typically stable at room temperature for extended periods, such as at least 10 weeks. In particular, the polyetheramine polyols are stable without exhibiting turbidity, precipitation, and / or significant increases in viscosity.

[0066] The polycondensation can be terminated in various ways. For example, the temperature can be lowered to a range where the reaction stops and the polycondensation product is stable on storage. This is generally the case below 100°C, preferably below 60°C, more preferably below 40°C, and most preferably at room temperature. Another possibility is to deactivate the catalyst by adding a basic component, for example a Lewis base or an organic or inorganic base. The polycondensation can be carried out in stirred-tank reactors or stirred-tank cascades. The process can be carried out batchwise, semi-continuously, or continuously.Polycondensation products of trialkanolamines and polycocondensation products of trialkanolamines as described herein are preferably used as polyetheramine polyol without chemical modification or derivatization.

[0067] Instead of a non-derivatized polycondensation product, a polycondensation product of trialkanolamines or a derivative of a polycocondensation product of a trialkanolamine can also be used.

[0068] Derivatives of such polycondensation and polycocondensation products of trialkanolamines include products obtained by alkoxylation of the hydroxyl end groups of the underivatized polycondensation and polycocondensation products. It is also possible to modify the underivatized polycondensation or polycocondensation products with hydrophobic or hydrophilic groups. Hydrophobization or hydrophilization can be achieved by reacting a portion of the hydroxyl end groups with selected reactants. The amino groups of the polycondensation and polycocondensation products can also be quaternized using alkylating agents to obtain permanently cationically modified polymers. Derivatives of such polycondensation and polycocondensation products of trialkanolamines are described, for example, in US 2011 / 0168045 AA, WO 2009 / 060060 A1 and WO 2009 / 112379 A1, to which reference is made.Preferred derivatization products within the meaning of the invention are alkoxylated polycondensation and polycocondensation products.

[0069] The polyetheramine polyol typically dissolves readily in a variety of solvents, such as water, alcohols such as methanol, ethanol, n-butanol, alcohol / water mixtures, acetone, 2-butanone, ethyl acetate, butyl acetate, methoxypropyl acetate, methoxyethyl acetate, tetrahydrofuran, dimethylformamide, dimethylacetamide, N-methylpyrrolidone, ethylene carbonate or propylene carbonate.

[0070] The aqueous binder composition usually contains the branched

[0071] Polyetheramine polyol in an amount of 0.01 to 10 wt.%, in particular 0.05 to 7.5 wt.%, in particular 0.1 to 5 wt.%, based on the dry mass of the weight of the carboxylated polymer of the aqueous polymer latex.

[0072] Aqueous polymer latex of a film-forming carboxylated polymer

[0073] The aqueous binder composition also contains an aqueous polymer latex of a film-forming carboxylated polymer.

[0074] The term "film-forming" in the context of the polymer latex refers to the ability of the carboxylated polymer of the polymer latex to form a film on surfaces upon drying under application conditions. The polymer often has a film-forming temperature of 50°C or less, especially 30°C or less. The film-forming temperature can be lowered, for example, by adding film-forming aids such as plasticizers and / or solvents.

[0075] The ability of the latex polymer to form a film under application conditions depends on its glass transition temperature. Generally, the carboxylated polymer of the aqueous polymer dispersions has a glass transition temperature T gin the range from -50 to +60°C, in particular from -40 to +50°C, in particular in the range from -30 to +30°C. The glass transition temperature can be determined by the DSC method (Differential Scanning Calorimetry, 20 K / min, center point measurement) according to DIN 53765:1994-03 or ISO 1 1357-2, preferably with sample preparation according to DIN EN ISO 16805:2005. In the case of a multiphase polymer containing two or more polymers or polymer phases with different glass transition temperatures, the glass transition temperatures of the individual polymer phases may lie outside the ranges specified here. The weight-average glass transition temperature T g However, (av) is calculated by the equation:

[0076] T g (av) = (T g (1)*wi + T g (2)*w2+ ... + Tg(n)*w n ).

[0077] It is often in the range of -50 to +60°C, especially from -40 to +50°C, especially in the range of -30 to +30°C. In the equation, T g (1), T g (2) to T g (n) the individual glass transition temperatures in K of the individual polymers 1 , 2 to n, while wi, W2 to w n indicate the proportion in weight percent of the individual polymers 1, 2 to n. For example, an aqueous latex of a multi-stage polymer containing 20 wt.% of a first polymer phase 1 with a T g of -10°C and 80 wt.% of a second polymer phase 2 with a T g of +40°C have a weight-average T g (av) = 34°C. If the polymer of the aqueous polymer dispersions contains polymers with different T g contains, the difference between the lowest T g and the highest T gas high as, for example, 100°C, for example from 10 to 100°C. Preferably, the polymer dispersed in the aqueous polymer dispersion has only a T g or, if there are polymers with different T g contains the maximum difference of the lowest T g and the highest T g 50K, especially not exceeding 20K.

[0078] According to Fox (TG Fox, Bull. Am. Phys. Soc. 1956, Vol. 1, page 123) and Ullmann's Encyclopedia of Industrial Chemistry (Vol. 19, page 18, 4th edition, Verlag Chemie, Weinheim, 1980), a good approximation of the glass transition temperature of not more than slightly cross-linked copolymers is:

[0079] 1 / T g (Fox) — Xi / T gi + x2 / T g 2 + . + Xn / T g n, where xi, X2,... x n the mass fractions of the monomers 1 , 2, ..., n and T g i, T g 2, .... , T gn. The glass transition temperatures are in degrees Kelvin of the polymers synthesized from only one of the monomers 1 , 2, ..., n. The T g Values ​​for the homopolymers of most monomers are known and can be found, for example, in Ullmann's Encyclopedia of Industrial Chemistry, 5th ed. A21, page 169, Verlag Chemie, Weinheim, 1992; other sources for glass transition temperatures of homopolymers are, for example, J. Brandrup, EH Immergut, Polymer Handbook, 1st ed., J. Wiley, New York 1966, 2nd ed. J. Wiley, New York 1975, and 3rd ed. J. Wiley, New York 1989.

[0080] In the case of a multi-stage polymer containing two polymers or polymer phases with different glass transition temperatures, the glass transition temperature of one phase is typically above 40°C, preferably at least 60°C, as determined by DSC as described herein. According to Fox, the glass transition temperature of the other phase is typically below 40°C, preferably at most 30°C, as determined by DSC as described herein.

[0081] In the case of a multi-stage polymer containing two polymers or polymer phases with different glass transition temperatures, the polymer preferably contains 95 to 40 wt.%, based on the total weight of the polymer, of the polymer with the lower glass transition temperature, which is usually below 40°C, and 5 to 60 wt.%, based on the total weight of the polymer, of the polymer with the higher glass transition temperature, which is usually above 40°C.

[0082] The term "carboxylated polymer" means that the latex polymer contains carboxyl groups bonded to the polymer backbone. Typically, the carboxyl groups are incorporated into the polymer via polymerized ethylenically unsaturated monomers containing one or more carboxyl groups. Such monomers are typically selected from monoethylenically unsaturated monocarboxylic acids with 3 to 6 carbon atoms and monoethylenically unsaturated dicarboxylic acids with 4 to 6 carbon atoms.

[0083] Examples of such monomers are acrylic acid, methacrylic acid, crotonic acid, 2-ethylpropenoic acid, 2-propylpropenoic acid, itaconic acid and fumaric acid.

[0084] The carboxylated polymer of the film-forming polymer latex is typically obtainable by radical copolymerization of a monomer M, which forms the carboxylated monomer latex. These monomers M, also referred to as monomer composition M, contain at least one monoethylenically unsaturated monomer having at least one carboxyl group, selected, for example, from monoethylenically unsaturated monocarboxylic acids having 3 to 6 carbon atoms and monoethylenically unsaturated dicarboxylic acids having 4 to 6 carbon atoms, and at least one further neutral ethylenically unsaturated monomer that is essentially water-insoluble, i.e., that has a solubility in deionized water of at most 50 g / l at 20°C. Typically, the monomer composition comprises 0.05 to 10 wt. %, based on the total weight of the monomers contained in the monomer composition.

[0085] In particular, the monomer composition M consists essentially of a) one or more ethylenically unsaturated monomers M1 which have a solubility in deionized water of at most 50 g / l at 20°C and which are in particular selected Ci-C2o-alkyl esters of monoethylenically unsaturated monocarboxylic acids having 3 to 6 C atoms, di-Ci-C2o-alkyl esters of monoethylenically unsaturated dicarboxylic acids having 4 to 6 C atoms, C5-C20-cycloalkyl esters of monoethylenically unsaturated monocarboxylic acids having 3 to 6 C atoms, vinyl esters of Ci-C2o-alkanoic acids, vinyl aromatic monomers, C2-Ce monoolefins and butadiene; b) one or more monoethylenically unsaturated monomers M2 selected from monoethylenically unsaturated monocarboxylic acids having 3 to 6 C atoms and monoethylenically unsaturated dicarboxylic acids having 4 to 6 C atoms; c) optionally one or more nonionic monomers M3 different from monomers M1.

[0086] The term “consisting essentially of” in this context means that the total amount of the monomers M1, M2 and M3 constitutes at least 95% by weight, in particular at least 99% by weight or 100% by weight of the total amount of monomers in the monomer composition.

[0087] Examples of monomers M1 include, but are not limited to

[0088] Ci-C2o-alkyl esters of monoethylenically unsaturated monocarboxylic acids having 3 to 6 C atoms, such as Ci-C2o-alkyl esters of acrylic acid, such as methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, 2-butyl acrylate, isobutyl acrylate, n-pentyl acrylate, n-hexyl acrylate, n-octyl acrylate, 2-ethylhexyl acrylate, n-decyl acrylate, 2-propylheptyl acrylate, lauryl acrylate, Ci2 / Ci4-alkyl acrylate and stearyl acrylate, C1-C20-alkyl esters of methacrylic acid, such as methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, 2-butyl methacrylate, isobutyl methacrylate, tert-butyl methacrylate, n-

[0089] Pentyl methacrylate, n-hexyl methacrylate, n-octyl methacrylate, 2-

[0090] Ethylhexyl methacrylate, n-decyl methacrylate, 2-propylheptyl methacrylate, lauryl methacrylate, Ci2 / Ci4-alkyl methacrylate and stearyl methacrylate;

[0091] Di-Ci-C2o-alkyl esters of monoethylenically unsaturated dicarboxylic acids having 4 to 6 C atoms, such as di-Ci-C2o-alkyl esters of itaconic acid, di-Ci-C2o-alkyl esters of citraconic acid, di-Ci-C2o-alkyl esters of maleic acid and di-Ci-C2o-alkyl esters of fumaric acid;

[0092] Cs-C2o-cycloalkyl esters of monoethylenically unsaturated monocarboxylic acids having 3 to 6 C atoms, Cs-C2o-cycloalkyl esters of acrylic acid and Cs-C2o-cycloalkyl esters of methacrylic acid;

[0093] Vinyl esters of Ci-C2o-alkanoic acids; vinyl aromatic monomers such as monovinyl-substituted aromatic hydrocarbons such as styrene, 2-methylstyrene, 4-methylstyrene, 2-n-butylstyrene, 4-n-butylstyrene, 4-n-decylstyrene and alpha-methylstyrene;

[0094] C2-C6 monoolefins and butadiene.

[0095] In a preferred embodiment, the monomers M1 are a mixture of at least one monomer M1a selected from C1-C20 alkyl esters of acrylic acid and C5-C20 alkyl esters of methacrylic acid; and at least one monomer M1b selected from vinylaromatic monomers and C1-C4 alkyl esters of methacrylic acid, and mixtures thereof.

[0096] Suitable monomers M1a are:

[0097] C1-C20-alkyl esters of acrylic acid, such as methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, 2-butyl acrylate, isobutyl acrylate, n-pentyl acrylate, n-hexyl acrylate, n-octyl acrylate, 2-ethylhexyl acrylate, n-decyl acrylate, 2-propylheptyl acrylate, lauryl acrylate, C12 / C14-alkyl acrylate and stearyl acrylate; C5-C20-alkyl esters of methacrylic acid, such as n-pentyl methacrylate, n-hexyl methacrylate, n-octyl methacrylate, 2-ethylhexyl methacrylate, n-decyl methacrylate, 2-propylheptyl methacrylate, lauryl methacrylate, C12 / C14-alkyl methacrylate and stearyl methacrylate; and mixtures thereof.

[0098] Suitable monomers M1 b are:

[0099] Ci-C4-alkyl esters of methacrylic acid, such as methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, 2-butyl methacrylate, isobutyl methacrylate and tert-butyl methacrylate, particularly preferably methyl methacrylate;

[0100] Vinyl aromatic monomers, in particular monovinyl-substituted aromatic hydrocarbons such as styrene, 2-methylstyrene, 4-methylstyrene, 2-n-butylstyrene, 4-n-butylstyrene, 4-n-decylstyrene and alpha-methylstyrene, particularly preferably styrene; and mixtures thereof.

[0101] The monomers M1a are preferably selected from C2-C12 alkyl esters of acrylic acid, in particular from ethyl acrylate, n-butyl acrylate, n-hexyl acrylate, n-octyl acrylate, 2-ethylhexyl acrylate and 2-propylheptyl acrylate.

[0102] Preferably, the monomers M1 b are selected from vinylaromatic monomers and Ci-C4 alkyl esters of methacrylic acid and mixtures thereof, in particular from styrene, methyl methacrylate.

[0103] In the mixtures of the monomers M1a and M1b, the relative amount of M1a and M1b can vary in particular from 10:1 to 1:10, in particular from 5:1 to 1:5, in particular from 3:1 to 1:3.

[0104] Examples of monomers M2 include, but are not limited to, acrylic acid, methacrylic acid, crotonic acid, 2-ethylpropenoic acid, 2-propylpropenoic acid, itaconic acid, and fumaric acid. Monocarboxylic acids are preferred. Acrylic acid, methacrylic acid, and mixtures thereof are particularly preferred.

[0105] Particularly preferably, the monomer M2 is selected from methacrylic acid or a mixture of acrylic acid and methacrylic acid.

[0106] Examples of monomers M3 include, but are not limited to, primary amides of monoethylenically unsaturated monocarboxylic acids having 3 to 8 carbon atoms (monomers M3.1), such as acrylamide and methacrylamide;

[0107] N-Ci-Cio-alkylamides of monoethylenically unsaturated monocarboxylic acids having 3 to 6 C atoms (monomers M3.2), in particular N-Ci-Cw-alkylamides of acrylic acid or methacrylic acid, such as N-methylacrylamide, N-ethylacrylamide, N-propylacrylamide, N-isopropylacrylamide, N-butylacrylamide, N-methylmethacrylamide, N-ethylmethacrylamide, N-propylmethacrylamide, N-isopropylmethacrylamide and N-butylmethacrylamide; monoethylenically unsaturated monomers with urea or keto groups (monomers M3.3), such as 2-(2-oxo-imidazolidin-1-yl)ethyl (meth)acrylate, 2-ureido (meth)acrylate, N-[2-(2-oxooxazolidin-3-yl)ethyl] methacrylate,

[0108] Acetoacetoxyethyl acrylate, Acetoacetoxypropyl methacrylate,

[0109] Acetoacetoxybutyl methacrylate, 2-(acetoacetoxy)ethyl methacrylate, diacetoneacrylamide (DAAM) and diacetone methacrylamide;

[0110] Hydroxyalkyl esters of monoethylenically unsaturated C8-C12 monocarboxylic acids (monomers M3.4), in particular hydroxyalkyl esters of acrylic acid and hydroxyalkyl esters of methacrylic acid, hereinafter also referred to as hydroxyalkyl. (Meth)acrylates, in particular hydroxy-C2-C4 alkyl esters of acrylic acid and hydroxy-C2-C4 alkyl esters of methacrylic acid, such as 2-hydroxyethyl acrylate, 3-hydroxypropyl acrylate, 4-hydroxybutyl acrylate, 2-hydroxyethyl methacrylate, 3-hydroxypropyl methacrylate, 4-hydroxybutyl methacrylate, etc.;

[0111] Monoethylenically unsaturated monomers carrying at least one tri-Ci-C4 alkoxysilane group (monomers M3.5), such as vinyltrimethoxysilane, vinyltriethoxysilane, methacryloxyethyltrimethoxysilane,

[0112] Methacryloxyethyltriethoxysilane and mixtures thereof. The amount of the mentioned monomers M3.5 will often be in the range of 0.01 to 1 ppm.

[0113] The M3 monomers may also contain small amounts of polyethylenically unsaturated monomers (monomers M3.6), i.e., monomers with at least two non-conjugated ethylenically unsaturated double bonds. The amounts of the above-mentioned M3.6 monomers will generally not exceed 1 ppm. Suitable M3.6 monomers include:

[0114] Diesters of monoethylenically unsaturated Cs-Ce monocarboxylic acids with saturated aliphatic or cycloaliphatic diols, in particular diesters of acrylic acid or methacrylic acid, such as the diacrylates and dimethacrylates of ethylene glycol (1,2-ethanediol), propylene glycol (1,2-propanediol), 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, neopentyl glycol (2,2-dimethyl-1,3-propanediol) or 1,2-cyclohexanediol;

[0115] Monoesters of monoethylenically unsaturated Cs-Ce monocarboxylic acids with monoethylenically unsaturated aliphatic or cycloaliphatic monohydroxy compounds, such as the acrylates and methacrylates of vinyl alcohol (ethanol), allyl alcohol (2-propen-1-ol), 2-cyclohexen-1-ol or norbornenol and divinyl aromatic compounds, such as 1,3-divinylbenzene, 1,4-divinylbenzene and mixtures thereof.

[0116] In a particular embodiment of the invention, the monomers M do not contain any monomers M3.6 or not more than 0.1 pphm of the monomers M3.6.

[0117] Among the monomers M3, hydroxyalkyl esters of acrylic acid and hydroxyalkyl esters of acrylic acid are preferably methacrylic acid, in particular hydroxy-C2-C4-alkyl esters of acrylic acid and hydroxy-C2-C4-alkyl esters of methacrylic acid, acrylamide, methacrylamide and mixtures thereof.

[0118] The carboxylated polymer is preferably obtainable by polymerization of a monomer composition M, wherein the monomer composition M essentially consists of a) 70 to 99.95 wt.%, in particular 80 to 99.9 wt.%, especially 90 to 99.8 wt.%, based on the total weight of the monomers of the monomer composition M, of one or more monoethylenically unsaturated monomers M1 as defined herein, b) 0.05 to 10 wt.%, in particular 0.1 to 8 wt.%, in particular 0.2 to 5 wt.%, based on the total weight of the monomers of the monomer composition M, of one or more monoethylenically unsaturated monomers M2 as defined herein, c) 0 to 20 wt.%, in particular 0 to 10 wt.%, in particular 0 to 5 wt.%, based on the total weight of the monomers of the monomer composition M, of one or more non-ionic monomers M3 as defined herein, which the monomers M1 are different.

[0119] The carboxylated polymer is obtainable in particular by polymerizing a monomer composition M, wherein the monomer composition M consists of a) one or more ethylenically unsaturated monomers M1 selected from the group consisting of at least one monomer M1a selected from C1-C20 alkyl esters of acrylic acid and Cs-C20 alkyl esters of methacrylic acid; and at least one monomer M1b selected from vinylaromatic monomers and C1-C4 alkyl esters of methacrylic acid and mixtures thereof, b) one or more monoethylenically unsaturated monomers M2 selected from the group consisting of monoethylenically unsaturated monocarboxylic acids having 3 to 6 C atoms and monoethylenically unsaturated dicarboxylic acids having 4 to 6 C atoms; c) optionally one or more nonionic monomers M3 which are different from monomers M1.

[0120] In a preferred embodiment, the film-forming carboxylated polymer is obtainable by polymerizing a monomer composition M, wherein the monomer composition M essentially consists of a) 70 to 99.95 wt.%, in particular 80 to 99.9 wt.%, in particular 90 to 99.8 wt.%, based on the total weight of the monomers of the monomer composition M, of one or more monoethylenically unsaturated monomers M1, which are selected from the group consisting of

[0121] - at least one monomer M1a selected from C1-C20 alkyl esters of acrylic acid and Cs-C2o alkyl esters of methacrylic acid; and

[0122] - at least one monomer M 1 b selected from vinyl aromatic monomers and C 1 -C 4 alkyl esters of methacrylic acid and mixtures thereof, b) 0.05 to 10% by weight, in particular 0.1 to 8% by weight, in particular 0.2 to 5% by weight, based on the total weight of the monomers of the monomer composition M, of one or more monoethylenically unsaturated monomers M2 as defined herein, c) 0 to 20% by weight, in particular 0 to 10% by weight, in particular 0 to 5% by weight, based on the total weight of the monomers of the monomer composition M, of one or more non-ionic monomers M3 as defined herein, which are different from the monomers M1.

[0123] In the aqueous carboxylated polymer latex, the dispersed polymers are present in the form of polymer particles. The polymer particles typically have an average diameter in the range of 50 to 500 nm, in particular in the range of 60 to 400 nm, and especially in the range of 80 to 300 nm. The average particle diameter, as referred to herein, refers to the Z-average particle diameter as determined by photon correlation spectroscopy (PCS), also known as quasielastic light scattering (QELS) or dynamic light scattering (DLS). The measurement method is described in ISO 13321:1996. The determination can be carried out using a HPPS (High Performance Particle Sizer). For this purpose, a sample of the aqueous polymer latex is diluted and the dilution is analyzed. In the context of DLS, the aqueous dilution can have a polymer concentration in the range of 0.001 to 0.5 wt.%, depending on the particle size.For most purposes, a suitable concentration is 0.01 wt%. However, higher or lower concentrations can be used to achieve an optimal signal-to-noise ratio. Dilution can be achieved by adding the polymer latex to water or an aqueous solution of a surfactant to avoid flocculation. Typically, dilution is achieved by using a 0.1 wt% aqueous solution of a non-ionic emulsifier, e.g., an ethoxylated C16 / C18 alkanol (degree of ethoxylation 18), as the diluent. Measurement configuration: HPPS from Malvern, automated, with continuous-flow cuvette and Gilson autosampler. Parameters: Measurement temperature 20.0°C; measurement time 120 seconds (6 cycles of 20 seconds); scattering angle 173°; dependent on particle size. Laser wavelength 633 nm (HeNe); Refractive index of the medium 1.332 (aqueous); viscosity 0.9546 mPa-s. The measurement results in a mean value of the second-order cumulant analysis (mean of fits), ieZ-mean. The "mean of fits" is an average, intensity-weighted hydrodynamic particle diameter in nm.

[0124] Preferably, the polymers in the polymer dispersion have a narrow particle size distribution. The particle size distribution is characterized by the polydispersity index, which is a dimensionless number calculated from a simple two-parameter fit to the correlation data from the cumulant analysis. The calculation is typically performed as described in ISO 13321:1996. Often, the PDI will be less than 0.2.

[0125] The polymer latex of the carboxylated polymer is usually obtainable by aqueous radical emulsion polymerization, in particular by radical aqueous emulsion polymerization, of the monomers M forming the carboxylated monomer latex, analogously to known processes of radical emulsion polymerization technology. The conditions required for carrying out the radical emulsion polymerization of the monomers M are sufficiently familiar to the person skilled in the art, for example from the prior art cited at the beginning and from "Emulsion Polymerization" in Encyclopedia of Polymer Science and Engineering, vol. 8, pages 659 ff. (1987); D.C. Blackley, in High Polymer Latices, vol. 1, pages 35 ff. (1966); H. Warson, The Applications of Synthetic Resin Emulsions, Chapter 5, pages 246 ff. (1972); D.Diederich, Chemistry in Our Time 24, pages 135 to 142 (1990); Emulsion Polymerization, Interscience Publishers, New York (1965); DE-A 40 03 422 and Dispersions of Synthetic High Polymers, F. Hölscher, Springer-Verlag, Berlin (1969)].

[0126] Radically initiated aqueous emulsion polymerization is triggered by a radical polymerization initiator (radical initiator). These can generally be peroxides or azo compounds. Redox initiator systems are also suitable. Peroxides that can be used include, in principle, inorganic peroxides such as hydrogen peroxide or peroxodisulfates, such as the mono- or dialkali metal or ammonium salts of peroxodisulfuric acid, for example, the mono- and disodium, potassium, or ammonium salts, or organic peroxides such as alkyl hydroperoxides, e.g., tert-butyl hydroperoxide, p-menthyl hydroperoxide, or cumyl hydroperoxide, as well as dialkyl or diaryl peroxides, such as di-tert-butyl or dicumyl peroxide. The azo compounds used are mainly 2,2'-azobis(isobutyronitrile), 2,2'-azobis(2,4-dimethylvaleronitrile) and 2,2'-azobis(amidinopropyl)dihydrochloride (AIBA, equivalent to V-50 from Wako Chemicals).The peroxides mentioned above, as well as dihydroxymaleic acid, benzoin and / or ascorbic acid and reducing saccharides such as sorbose, glucose, fructose and / or dihydroxyacetone, are essentially suitable as oxidizing agents for redox initiator systems.

[0127] Preferred free-radical initiators are inorganic peroxides, especially peroxodisulfates, and redox initiator systems. In general, the amount of free-radical initiator used, based on the total amount of monomers M, is 0.01 to 5 pphm, preferably 0.1 to 3 pphm. The amount of free-radical initiator required for the emulsion polymerization M can be introduced entirely into the polymerization vessel. However, it is also possible to add no or only a portion of the free-radical initiator, for example not more than 30% by weight, in particular not more than 20% by weight.-%, based on the total amount of the radical required initiator into the aqueous polymerization medium and then, under polymerization conditions during the radical emulsion polymerization of the monomers M, adding the entire amount or any remaining amount, depending on consumption, discontinuously in one or more portions or continuously at a constant or varying flow rate.

[0128] Preferably, the radical emulsion polymerization of the monomers forming the carboxylated polymer latex is carried out by a so-called feed process, which means that at least 90%, in particular at least 95%, or the entire amount of the monomers are polymerized and added to the polymerization reaction under polymerization conditions during a metering period P. The duration of the period P can depend on the production plant and vary from, for example, 20 minutes to 12 hours. Frequently, the duration of the period P will be in the range from 0.5 h to 5 h, in particular from 1 h to 4 h.

[0129] The term "polymerization conditions" generally refers to temperatures and pressures under which free-radical initiation of aqueous emulsion polymerization proceeds at a sufficient polymerization rate. These conditions depend, in particular, on the free-radical initiator used. Advantageously, the type and amount of free-radical initiator, polymerization temperature, and polymerization pressure are selected such that a sufficient amount of initiating radicals is always present to initiate or maintain the polymerization reaction. It may be expedient to adjust the polymerization conditions and initially charge at least a portion of the free-radical initiator to the polymerization vessel before commencing metering of the monomers M.

[0130] It has proven advantageous to conduct radical emulsion polymerization in the presence of seed latex. A seed latex is a polymer latex present in the aqueous polymerization medium before the start of metering of the monomers M. The seed latex can help to better adjust the particle size of the final polymer latex obtained in radical emulsion polymerization.

[0131] In principle, any polymer latex can serve as seed latex. Preferred for the purposes of the invention are seed latices in which the particle size of the polymer particles is comparatively small. In particular, the Z-average particle diameter of the polymer particles of the seed latex, determined by dynamic light scattering at 20°C (see below), is preferably in the range from 10 to 80 nm, in particular from 10 to 50 nm. The polymer particles of the seed latex preferably consist of ethylenically unsaturated monomers which contain at least 95% by weight, based on the total weight of the monomers forming the seed latex, of one or more monomers M1a and / or M1b as defined above. The polymer particles of the seed latex contain, in particular, at least 95% by weight, based on the total weight of the monomers forming the seed latex.

[0132] Typically, the seed latex is initially introduced into the polymerization vessel before the metering of the monomers M begins. In particular, the seed latex is introduced into the polymerization vessel, and the polymerization conditions are then adjusted, e.g., by heating the mixture to the polymerization temperature. It may be advantageous to add at least a portion of the free-radical initiator to the polymerization vessel before the metering of the monomers M begins. However, it is also possible to meter the monomers and the free-radical polymerization initiator in parallel with the polymerization vessel.

[0133] The amount of seed latex, calculated as solids, can frequently range from 0.1 to 10 wt.%, in particular from 0.5 to 5 wt.%, based on the total weight of the monomers M to be polymerized. Free-radical aqueous emulsion polymerization can be carried out at temperatures ranging from 0 to 170°C. Applied temperatures are generally in the range from 50 to 120°C, frequently from 60 to 120°C, and often from 70 to 110°C. Free-radical aqueous emulsion polymerization can be carried out at a pressure of less than, equal to, or more than 1 atm (atmospheric pressure), and thus the polymerization temperature can exceed 100°C and be as high as 170°C.

[0134] The polymerization of the monomers is usually carried out at ambient pressure, but it can also be carried out under elevated pressure. The pressure can be 1.2, 1.5, 2.5, 10, 15 bar (absolute), or even higher. If emulsion polymerizations are carried out under vacuum, pressures of 950 mbar, frequently 900 mbar, and often 850 mbar (absolute) are reached.

[0135] Advantageously, the radical aqueous emulsion polymerization is carried out at ambient pressure (approx. 1 atm) under exclusion of oxygen, for example under an inert gas atmosphere, for example under nitrogen or argon.

[0136] The polymerization of the monomers M can optionally be carried out in the presence of chain transfer agents. Chain transfer agents are compounds that transfer free radicals and reduce the molecular weight of the molecules or control chain growth during polymerization. Examples of chain transfer agents are aliphatic and / or araliphatic halogen compounds, for example n-butyl chloride, n-butyl bromide, n-butyl iodide, methylene chloride, ethylene dichloride, chloroform, bromoform, bromotrichloromethane, dibromodichloromethane, carbon tetrachloride, carbon tetrabromide, benzyl chloride, benzyl bromide, organic thio compounds, such as primary, secondary or tertiary aliphatic thiols, for example ethanethiol, n-propanethiol, 2-propanethiol, n-butanethiol, 2-butanethiol, 2-methyl-2-propanethiol, n-pentanethiol, 2-pentanethiol, 3-pentanethiol, 2-methyl-2-butanethiol, 3-methyl-2-butanethiol, n-hexanethiol, 2-hexanethiol, 3-hexanethiol, 2-methyl-2-pentanethiol,3-Methyl-2-pentanethiol, 4-Methyl-2-pentanethiol, 2-Methyl-3-pentanethiol, 3-Methyl-3-pentanethiol, 2-Ethylbutanethiol, 2-Ethyl-2-butanethiol, n-Heptanethiol and its isomeric compounds, n-Octanethiol and its isomeric compounds, n-Nonanthiol and its isomeric compounds, n-Decanethiol and the isomeric compounds thereof, n-Undecanethiol and the isomeric compounds thereof, n-Dodecanethiol and its isomeric compounds, n-Tridecanethiol and its isomeric compounds, substituted thiols, for example 2-Hydroxyethanethiol, aromatic thiols such as benzenethiol, ortho-, meta- or para-methylbenzenethiol, alkyl esters of mercaptoacetic acid (thioglycolic acid), such as 2- Ethylhexyl thioglycolate, alkyl esters of mercaptopropionic acid, such as octyl mercaptopropionate, and other sulfur compounds, described in Polymer Handbook, 3rd edition, 1989, J. Brandrup and EH Immergut, John Wiley & Sons, Section II, pages 133 to 141, but also aliphatic and / or aromatic aldehydes,such as acetaldehyde, propionaldehyde, and / or benzaldehyde; unsaturated fatty acids such as oleic acid; dienes with non-conjugated double bonds such as divinylmethane or vinylcyclohexane; or hydrocarbons with easily abstracted hydrogen atoms, for example, toluene. Alternatively, mixtures of the aforementioned chain transfer agents can be used that do not interfere with each other. The total amount of chain transfer agents optionally used in the process, based on the total amount of monomers M, will generally not exceed 1 wt.%. However, it is possible that during a certain period of the polymerization reaction, the amount of chain transfer agent added to the polymerization reaction exceeds 1 wt.%, based on the total amount of monomers already added to the polymerization reaction.

[0137] Radical emulsion polymerization is usually carried out in an aqueous polymerization medium which, in addition to water, contains at least one surface-active substance (surfactant) to stabilize the emulsion of the monomers and the polymer particles.

[0138] The surfactant can be selected from emulsifiers and protective colloids. In contrast to emulsifiers, protective colloids are polymeric compounds with molecular weights above 2000 Daltons, while emulsifiers typically have lower molecular weights. The surfactants can be anionic or nonionic, or mixtures of nonionic and anionic surfactants.

[0139] Anionic surfactants typically carry at least one anionic group selected from phosphate, phosphonate, sulfate, and sulfonate groups. Anionic surfactants that carry at least one anionic group are typically used in the form of their alkali metal salts, especially their sodium salts, or in the form of their ammonium salts. Preferred anionic surfactants are anionic emulsifiers, especially those that carry at least one sulfate or sulfonate group.

[0140] Examples of anionic emulsifiers which carry at least one sulfate or sulfonate group are, for example, the salts, in particular the alkali and ammonium salts, of alkyl sulfates, in particular of Cs-C22-alkyl sulfates, the salts, in particular the alkali and ammonium salts, of sulfuric acid monoesters of ethoxylated alkanols, in particular of sulfuric acid monoesters of ethoxylated Cs-C22-alkanols, preferably with a

[0141] Degree of ethoxylation (EO level) in the range from 2 to 40, the salts, in particular the alkali and ammonium salts, of sulfuric acid monoesters of ethoxylated alkylphenols, in particular of sulfuric acid monoesters of ethoxylated C4-C18-alkylphenols (EO content preferably 3 to 40), the salts, in particular the alkali and ammonium salts, of alkylsulfonic acids, in particular of C8-C22-alkylsulfonic acids, the salts, in particular the alkali and ammonium salts, of dialkyl esters, in particular C4-C18-alkyl esters of sulfosuccinic acid, the salts, in particular the alkali and ammonium salts, of alkylbenzenesulfonic acids, in particular of C4-C22-alkylbenzenesulfonic acids, and the salts, in particular the alkali and ammonium salts, of mono- or disulfonated, alkyl-substituted diphenyl ethers, for example of Bis(phenylsulfonic acid) ethers which carry a C4-C24 alkyl group on one or both aromatics.The latter are well known, for example from US-A-4,269,749, and are commercially available, for example as Dowfax® 2A1 (Dow Chemical Company).

[0142] Mixtures of the aforementioned salts are also suitable.

[0143] Preferred anionic surfactants are anionic emulsifiers selected from the following groups: the salts, in particular the alkali and ammonium salts, of alkyl sulfates, in particular of Cs-C22-alkyl sulfates, the salts, in particular the alkali metal salts, of sulfuric acid monoesters of ethoxylated alkanols, in particular of sulfuric acid monoesters of ethoxylated Cs-C22-alkanols, preferably with an ethoxylation degree (EO level) in the range from 2 to 40, of sulfuric acid monoesters of ethoxylated alkylphenols, in particular of sulfuric acid monoesters of ethoxylated C4-C18-alkylphenols (EO content preferably 3 to 40), of alkylbenzenesulfonic acids, in particular of C4-C22-alkylbenzenesulfonic acids, and of mono- or disulfonated, alkyl-substituted diphenyl ethers, for example of bis(phenylsulfonic acid) ethers, which carry a C4-C24 alkyl group on one or both aromatic rings.

[0144] Examples of anionic emulsifiers carrying a phosphate or phosphonate group include, but are not limited to, the following salts selected from the following groups: the salts, in particular the alkali metal and ammonium salts, of mono- and dialkyl phosphates, in particular C8-C22 alkyl phosphates, the salts, in particular the alkali metal and ammonium salts, of phosphoric acid half-esters of C2-C3 alkoxylated alkanols, preferably with a degree of alkoxylation in the range from 2 to 40, in particular in the range from 3 to 30, e.g. phosphoric acid monoesters of ethoxylated Cs-C22 alkanols, preferably with a degree of ethoxylation (EO level) in the range from 2 to 40, phosphoric acid monoesters of propoxylated Cs-C22 alkanols, preferably with a degree of propoxylation (PO level).) in the range from 2 to 40 and phosphoric acid half esters of ethoxylated-co-propoxylated Cs-C22 alkanols, preferably with a degree of ethoxylation (EO level) in the range from 1 to 20 and a degree of propoxylation from 1 to 20, the salts, in particular the alkali metal and ammonium salts, of phosphoric acid monoesters of ethoxylated alkylphenols, in particular phosphoric acid monoesters of ethoxylated C4-C18 alkylphenols (EO content preferably 3 to 40), the salts, in particular the alkali metal and ammonium salts, of alkylphosphonic acids, in particular C8-C22 alkylphosphonic acids and the salts, in particular the alkali metal and ammonium salts, of alkylbenzenephosphonic acids, in particular C8-C22 alkylbenzenephosphonic acids.

[0145] Further suitable anionic surfactants can be found in Houben-Weyl, Methods of Organic Chemistry, Volume XIV / 1, Macromolecular Materials, Georg-Thieme-Verlag, Stuttgart, 1961, pp. 192-208. The surfactant preferably comprises at least one anionic emulsifier carrying at least one sulfate or sulfonate group, which contains at least one anionic emulsifier carrying at least one sulfate or sulfonate group. This can be the only type of anionic emulsifier. However, mixtures of at least one anionic emulsifier carrying at least one sulfate or sulfonate group and at least one anionic emulsifier carrying at least one phosphate or phosphonate group can also be used. In such mixtures, the amount of at least one anionic emulsifier carrying at least one sulfate or sulfonate group is preferably at least 50% by weight, based on the total weight of the anionic surfactants used in the process.In particular, the amount of anionic emulsifiers carrying at least one phosphate or phosphonate group must not exceed 20% by weight, based on the total weight of the anionic surfactants used in the process.

[0146] In addition to the aforementioned anionic surfactants, the surfactant may also contain one or more nonionic surface-active substances, which are particularly selected from nonionic emulsifiers. Suitable nonionic emulsifiers include, for example, araliphatic or aliphatic nonionic emulsifiers, for example, ethoxylated mono-, di-, and trialkylphenols (EO level: 3 to 50, alkyl radical: C4-C10), ethoxylates of long-chain alcohols (EO level: 3 to 100, alkyl radical: Cs-Cc), and polyethylene oxide / polypropylene oxide homopolymers and copolymers. These can contain the alkylene oxide units in a random distribution or in the form of polymerized blocks. EO / PO block copolymers are very suitable examples.Preference is given to ethoxylates of long-chain alkanols, in particular those having an average degree of ethoxylation of 5 to 100 in the alkyl radical Cs-Cao and, among these, particularly preferably those having a linear C12-C20 alkyl radical and an average degree of ethoxylation of 10 to 50, as well as ethoxylated monoalkylphenols.

[0147] In a particular embodiment of the invention, the surfactants used in the process contain less than 20 wt.%, in particular at most 10 wt.

[0148] % nonionic surfactants, based on the total amount of surfactants used in the process of the present invention, and in particular contain no nonionic surfactant. In another embodiment of the invention, the surfactants used in the process of the present invention comprise at least one anionic surfactant and at least one nonionic surfactant, the ratio of anionic surfactants to nonionic surfactants usually being in the range of 0.5:1 to 10:1, in particular 1:1 to 5:1.

[0149] Preferably, the surfactant will be used in an amount such that the amount of surfactant is in the range from 0.2 to 5% by weight, in particular in the range from 0.5 to 3% by weight, based on the monomers M.

[0150] The aqueous reaction medium during the polymerization may in principle also contain minor amounts (usually at most 5 wt.%) of water-soluble organic solvents, for example methanol, ethanol, isopropanol, butanols, pentanoic acid, but also acetone, etc. However, the process is preferably carried out in the absence of such solvents.

[0151] It is often advantageous to subject the aqueous polymer dispersion obtained after completion of the polymerization of the monomers M to a post-treatment to reduce the residual monomer content. This post-treatment is carried out either chemically, e.g., by completing the polymerization reaction with a more effective free-radical initiator system (so-called post-polymerization), and / or physically, e.g., by stripping the aqueous polymer dispersion with steam or inert gas. Corresponding chemical and physical processes are familiar to the person skilled in the art—see, for example, EP-A 771328, DE-A 19624299, DE-A 19621027, DE-A 19741184, DE-A 19741187, DE-A 19805122, DE-A 19828183, DE-A 19839199, DE-A 19840586, and DE-A 19847115.The combination of chemical and physical post-treatment has the advantage that it removes not only the unreacted ethylenically unsaturated monomers but also other disruptive volatile organic compounds (VOCs) from the aqueous polymer dispersion.

[0152] The polymer latex of the carboxylated polymer is obtainable, for example, by a single-stage or multi-stage emulsion polymerization, in particular an aqueous radical emulsion polymerization, of a monomer composition M. The term “multi-stage” is well understood in the context of aqueous emulsion polymerization and means that the relative concentration of the monomers in the monomer composition M added to the polymerization reaction is changed at least once during the aqueous emulsion polymerization. Such a process leads to at least two polymer populations of different monomer compositions in the polymer particles of the latex. For example, it will be possible to change the monomer composition such that the multi-stage latex polymer contains populations with different glass transition temperatures or a glass transition temperature (T g) gradient. It is also possible to change the monomer composition so that the multi-stage latex polymer has populations with different concentrations of polymerized acidic monomers, such as monomers M2, or a concentration gradient of monomers M2. During the addition of the monomers M, the type of monomers and / or their quantitative ratio can be changed continuously or stepwise. The polymerization reaction remains constant. For example, it is possible for the ratio of monomers M1 and M2 to increase or decrease during the addition.

[0153] Preferably, the aqueous polymer latex of the carboxylated polymer is prepared by a radical aqueous emulsion polymerization according to the so-called feed process, wherein during the feed of the monomer composition M at least 90% of the monomer composition M polymers to be polymerized are metered in under polymerization conditions during a metering time P of the polymerization reaction, and wherein the composition of the part of the monomer composition M which is metered in under polymerization conditions of the polymerization reaction is changed at least once during the metering time.

[0154] In a particular embodiment, the content of monomers M2 in the monomer composition M, i.e. the relative amount of monomers M2 to the weight of the monomer composition M fed to the polymerization reaction, is increased to a higher level for one or more limited time periods P(n). After each of these time periods, the relative amount of monomers M2 is reduced. During each of the periods P(n), the relative amount of monomers M2 to the total amount of monomers fed during this period is at least 0.5 pphm higher, in particular at least 1.0 pphm higher than the level outside the periods. In particular, the amount of monomers M2 fed during the periods P(n) is 0.5 to 80 pphm, in particular 1.0 to 50 pphm higher than the average amount of monomers M2 fed outside the periods P(n).

[0155] Here and throughout the description, and particularly in this embodiment, the term pphm (parts per hundred monomers) is used as a synonym for the relative amount of a particular monomer to the total amount of monomer composition M in wt.%. For example, x pphm of monomer M2 means x wt.% of monomers M2, based on the total amount of monomers of monomer composition M. An increase of y pphm means that the relative amount of a particular monomer is increased by y wt.%, based on the total weight of monomers of monomer composition M.

[0156] In this particular embodiment, there may be a single period P(n) during which the weight level of the monomers M2 is increased. However, there may also be more than one period P(n). The total number of periods P(n) is not particularly limited and can be up to 20 or even more. For practical reasons, the total number of periods P(n) will generally not exceed 10 and will in particular be from 1 to 6.

[0157] In this particular embodiment, the content of monomers M2 in the monomer composition M outside the periods P(n), i.e. the content of monomers M2 before and after each period P(n), can be the same or vary slightly. The fluctuation in the content of monomers M2 outside the periods P(n) is normally no more than 1 pphm, in particular no more than 0.5 pphm. The values ​​given here relate to the mean values ​​during the periods P(n) and outside the periods P(n). Preferably, the content of monomers M2 within the periods P(n) is in the range from 1.5 to 85 pphm, in particular 2 to 50 pphm.

[0158] In this particular embodiment, the period(s) P(n) in which the concentration of the acidic monomers M2 is increased may lie entirely within the period P or at the end of the period P. In this particular embodiment, it is important that the first period P(n) does not begin before at least 5% of the monomers M, in particular at least 10% of the monomers M subjected to the emulsion polymerization, have been metered into the polymerization reaction. During this period(s) P(n), the weight ratio of the acidic monomers M2 to the total amount of the other monomers M1 + M3 in the monomer composition metered into the polymerization reaction is frequently at least 0.02:1, in particular at least 0.03:1. Before each such period P(n), the ratio of the acidic monomers M2 to the total amount of the other monomers M1 + M3 should be less than 0.03:1, in particular less than 0.02:1.Likewise, at the end of each period P(n), the ratio of the acidic monomers M2 to the total amount of the other monomers M1 + M3 should be reduced to less than 0.03:1, in particular less than 0.02:1.

[0159] Preferably, the content of monomers M2 in the monomer composition and likewise the weight ratio of the acidic monomers M2 to the total amount of the other monomers M1 + M3 in the monomer composition M that is metered into the polymerization reaction can be manipulated. For example, a single feed line can be used to meter the monomers M into the polymerization reaction. By increasing the concentration of the monomers M2 in the single feed line of monomers M or by lowering the total concentrations of the monomers M1 + M3 or by both measures, the ratio of the acidic monomers M2 to the total amount of the other monomers M1 + M3 can be reduced or increased. A portion of the monomers M2, e.g. at least 20%, in particular at least 30%.

[0160] It can be seen that the total duration of all periods P(n) is shorter than the duration of period P required for the addition of the total amount of monomers M into the polymerization reaction. Often, the total duration of all periods P(n) does not exceed 50%, in particular 40%, and especially 30%, of the duration of period P.

[0161] Frequently, the total duration of all periods P(n) is at least 0.2%, in particular at least 0.5% and in particular at least 1% of the duration of period P. In particular, the ratio of the total duration of all periods P(n) to the duration of period P is from 0.002:1 to 0.5:1, in particular from 0.005:1 to 0.30:1. Frequently, the total duration of all periods P(n) is from 30 seconds to 60 minutes. The duration of an individual period P(n) is of minor importance and can be from a few seconds, e.g. 10 seconds, to 60 minutes or more. The duration of a period P can depend on the production plant and can vary from e.g. 20 minutes to 12 hours.

[0162] It will often be in the range of 0.5 h to 5 h, especially from 1 h to 4 h.

[0163] In this particular embodiment, it is possible to add the total amount of monomers M2 contained in the monomer composition M during the at least one period P(n), i.e., during all periods P(n). However, it is not necessary to add the total amount of monomers M2 during the at least one period P(n). Rather, it is preferred that outside of the periods P(n), the monomer composition added to the polymerization reaction still contains one or more monomers M2. Frequently, at least 20% of the monomers M2 contained in the monomer composition M, in particular at least 30% of the monomers M2 contained in the monomer composition M, are added to the polymerization reaction during the at least one period P(n).

[0164] The concentration of the polymer latex contained in the aqueous binder composition is often in the range of 10 to 70 wt%, in particular in the range of 30 to 69 wt%, in particular in the range of 40 to 68 wt% by weight, based on the total weight of the binder composition.

[0165] The aqueous binder composition typically consists of the aqueous polymer latex of a film-forming carboxylated polymer, as described herein, and the branched polyetheramine polyol, as described herein, and water. However, the aqueous binder composition may optionally contain other components such as dispersants, biocides, wetting agents, defoamers, rheology additives, and / or fillers.

[0166] Preferred embodiments of the aqueous binder composition contained in the water-based fire retardant compositions are those mentioned above.

[0167] In some embodiments, the aqueous binder is present in an amount of about 20 wt.% to about 50 wt.%, based on the total weight of the aqueous fire retardant composition. In some embodiments, the aqueous binder is present in an amount of about 25 wt.% to about 45 wt.%, preferably from about 30 wt.% to about 40 wt.%, based on the total weight of the aqueous fire retardant composition.

[0168] From EP 3910034 A1 it is known that the fire protection composition can only protect the component to which it is applied from fire or from the effects of high heat in the event of a fire if the fire protection composition forms an insulating layer after curing, the so-called fire protection coating. To ensure sufficient fire protection, the solids content of the fire protection composition according to the invention is at least 50 wt.% based on the total weight of the fire protection composition. The term "solids content" in the sense of the present invention describes the proportion of the compounds in the

[0169] Fire protection compositions that are solid at room temperature. Exceptions to this are binders that are solid at room temperature and which are

[0170] The solids content of the fire protection composition can thus be calculated from the filler content of the fire protection composition. The solids content is preferably in a range from 50% to 85% by weight, preferably in a range from 55% to 80% by weight, and more preferably in a range from 60% to 78% by weight.

[0171] The branched polyetheramine polyols described herein have a superior effect on the curing and / or hardening behavior of polymer binders, such as film-forming carboxylated polymers. In particular, the branched polyetheramine polyols accelerate the film formation process, resulting in accelerated curing of the binder, which overall accelerates the curing of the fire protection composition of the invention. Physically curing aqueous fire protection compositions can thus be applied in higher layer thicknesses, applied with less labor, and overlaid with additional coatings after a shorter waiting time.

[0172] Intumescent fire protection additives

[0173] According to the invention, the aqueous fire protection composition comprises at least one intumescent fire protection additive (also fire protection additive), wherein the fire protection additive can comprise both a single compound and a mixture of several compounds.

[0174] Intumescent fire protection additives are those that act by forming an inflated, insulating layer of flame-retardant material under the influence of heat, which protects the substrate from overheating and thus prevents or at least delays the change in the mechanical and static properties of load-bearing components due to the influence of heat.

[0175] The formation of a voluminous, insulating layer, namely an ash layer, can be achieved through the chemical reaction of a mixture of correspondingly matched compounds that react with each other upon exposure to heat. Such systems are known to those skilled in the art under the term chemical intumescence and can be used according to the invention. Alternatively, the voluminous, insulating layer can be formed by physical intumescence. Both systems can be used individually or together in combination according to the invention.

[0176] For the formation of an intumescent layer through chemical intumescence, at least three components are generally required for an intumescent fire protection additive: a carbon source, a dehydration catalyst (also called an acid generator), and a gas generator (also called a blowing agent), which are often contained in a binder. The components of the intumescent fire protection additive are selected in particular to enable synergy, with some of the compounds being able to fulfill multiple functions.

[0177] When exposed to heat, the binder softens and the fire-protection additives are released, allowing them to react with each other in the case of chemical intumescence or expand in the case of physical intumescence. Thermal decomposition of the dehydrogenation catalyst converts the acid into the carbon catalyst, which serves as a catalyst for the carbonization of the carbon source. At the same time, the gas-generating agent thermally decomposes, forming inert gases that cause the carbonized (charred) material and, if necessary, the softened binder to expand, forming a voluminous, insulating foam. It should be noted that in the aqueous fire-protection composition according to the invention, the aqueous binder itself also functions as a carbon source in the event of a fire, so it is not absolutely necessary to add further compounds that fulfill this function.Thus, all three compounds necessary for intumescence are present, whereby in this case the intumescent fire protection additive comprises at least one dehydrogenation catalyst and at least one gas generator.

[0178] In such an embodiment of the invention, in which the insulating layer is formed by chemical intumescence, the intumescent fire protection additive therefore comprises at least one dehydrogenation catalyst and at least one gas generator.

[0179] Suitable dehydrogenation catalysts, which also exhibit high storage stability in water-based dispersions, include the compounds commonly used in intumescent fire protection formulations and known to those skilled in the art, in particular a salt or ester of an inorganic, non-volatile acid selected from sulfuric acid, phosphoric acid, or boric acid. Coated phosphorus-containing compounds are primarily used, and their range is very broad, as they span several phosphorus oxidation states, such as phosphines, phosphine oxides, phosphonium compounds, phosphates, elemental red phosphorus, phosphites, and phosphates.Examples of phosphoric acid compounds include: monoammonium phosphate, diammonium phosphate, ammonium phosphate, ammonium polyphosphate, melamine phosphate, melamine resin phosphates, potassium phosphate, polyol phosphates such as pentaerythritol phosphate, glycerol phosphate, sorbitol phosphate, mannitol phosphate, dulcitol phosphate, neopentyl glycol phosphate, ethylene glycol phosphate, dipentaerythritol phosphate, and the like. A polyphosphate or an ammonium polyphosphate is preferably used as the phosphoric acid compound. Melamine resin phosphates are understood to be compounds such as reaction products of Lamelite C (melamine-formaldehyde resin) with phosphoric acid. Examples of sulfuric acid compounds include: ammonium sulfate, ammonium sulfamate, nitroaniline bisulfate, 4-nitroaniline-2-sulfonic acid, and 4,4-dinitrosulfanilamide, and the like. Examples of boric acid compounds include melamine borate.However, to simultaneously increase the storage stability of the water-based dispersion, coated and / or encapsulated acid generators are ideally suited for the present fire protection composition. Examples include the commercially available products Exolit® AP 462, Exolit® AP 750, Exolit® AP435, FR GROS® C70, FR GROS® 486, FR GROS® 584, and Exflam APP 205 from Clariant, Budenheim, and Wellchem. These products each feature a coating, for example, melamine, silicone, or epoxy.

[0180] Suitable gas generators are compounds commonly used in flame retardants and known to those skilled in the art, such as cyanuric acid or isocyanic acid and their derivatives, and melamine and their derivatives. These include cyanamide, dicyanamide, dicyandiamide, guanidine and its salts, biguanide, melamine cyanurate, cyanic acid salts, cyanic acid esters and amides, hexamethoxymethylmelamine, dimelamine pyrophosphate, melamine polyphosphate, and melamine phosphate. Hexamethoxymethylmelamine or melamine (cyanuric acid amide) is preferred.

[0181] Also suitable are components whose mode of action is not limited to a single function, such as melamine polyphosphate, which acts both as an acid generator and a gas generator. Further examples are described in GB 2 007 689 A1, EP 139 401 A1, and US 3 969 291 A1.

[0182] In a further embodiment of the invention, in which the insulating layer is formed by chemical intumescence, the intumescent fire protection additive comprises at least one (further) carbon supplier, at least one dehydrogenation catalyst and at least one gas generator.

[0183] Possible additional carbon sources include the compounds commonly used in intumescent fire protection formulations and known to the person skilled in the art, such as starch-like compounds, e.g. starch and modified starch, and / or polyhydric alcohols (polyols), such as saccharides and polysaccharides, and / or a thermoplastic or thermosetting polymeric resin binder, such as a phenolic resin, a urea resin, a polyurethane, polyvinyl chloride, poly(meth)acrylate, polyvinyl acetate, polyvinyl alcohol, a silicone resin, and / or a rubber. Suitable polyols are polyols from the group consisting of sugar, pentaerythritol, dipentaerythritol, tripentaerythritol, polyvinyl acetate, polyvinyl alcohol, sorbitol, and polyoxyethylene / polyoxypropylene (EO-PO) polyols. Pentaerythritol, dipentaerythritol, or polyvinyl acetate are preferably used.

[0184] Particularly preferred as an additional carbon source are compounds based on pentaerythritol, in which the free hydroxide groups are also protected by additional substituents, as they also exhibit high storage stability in water-based dispersions. Examples include pentaerythritol tetraacetate, pentaerythritol tetraacrylate, and pentaerythritol tetrabenzoate.

[0185] In one embodiment of the invention in which the insulating layer is formed by physical intumescence, the intumescent fire protection additive comprises at least one thermally expandable compound, such as a graphite intercalation compound, also known as expandable graphite.

[0186] Examples of suitable expandable graphite include known intercalation compounds of sulfuric acid, nitric acid, acetic acid, Lewis acids, and / or other strong acids in graphite. These are also referred to as graphite salts. Expandable graphites that release SO2, SO3, CO2, H2O, NO, and / or NO2 upon expansion at temperatures of, for example, 120 to 350°C are preferred. The expandable graphite can, for example, be in the form of platelets with a maximum diameter in the range of 0.1 to 5 mm. This diameter is preferably in the range of 0.5 to 3 mm. Expandable graphites suitable for the present invention are commercially available.

[0187] In a further embodiment of the invention, the insulating layer is formed by both chemical and physical intumescence, so that the intumescent fire protection additive comprises a carbon supplier, a dehydrogenation catalyst and a gas generator as well as thermally expandable compounds.

[0188] In principle, the intumescent fire protection additive can be present in the aqueous fire protection composition in a wide range of weight percentages. Preferably, the intumescent fire protection additive is present in the aqueous fire protection composition in an amount of more than 30 wt.%, whereby the amount depends essentially on the type of intumescent fire protection additive and the application method of the fire protection composition (spraying, brushing, etc.). To achieve the highest possible intumescence rate, the proportion in the fire protection composition is set as high as possible, while ensuring that the viscosity of the fire protection composition does not become too high, so that the fire protection composition can still be easily processed.

[0189] The intumescent fire protection additive is preferably present in the fire protection composition in a proportion of at least 30 wt. The proportion of intumescent fire protection additive is preferably in a range from 30 wt.% to 80 wt.%, preferably 35 wt.% to 75 wt.%, more preferably in a range from 35 wt.% to 70 wt.%, more preferably in a range from 40 wt.% to 60 wt.%, and even more preferably in a range from 40 wt.% to 55 wt.%, based on the total weight of the aqueous fire protection composition.

[0190] In the case of chemical intumescence, it is preferred that the proportion of the intumescent fire protection additive is 45 wt.% or more, in particular from 40 wt.% to 55 wt.%, based on the total weight of the aqueous fire protection composition.

[0191] In the case of physical intumescence, it is sufficient for a good intumescent effect that the proportion of the intumescent fire protection additive is 30 wt.% or more, based on the total weight of the aqueous fire protection composition.

[0192] Since the ash crust formed in a fire is generally too unstable and, depending on its density and structure, can be blown away by air currents, which negatively impacts the insulating effect of the fire protection coating, at least one ash crust stabilizer is preferably added to the fire protection additives listed above. The basic mechanism of action is that the inherently very soft carbon layers that form are mechanically strengthened by inorganic compounds (including inorganic framework formers). The addition of such an ash crust stabilizer contributes significantly to the stabilization of the intumescent crust in a fire, as these additives increase the mechanical strength of the intumescent layer and / or prevent it from dripping off.

[0193] In a particularly preferred embodiment of the invention, the aqueous fire protection composition further comprises fibrous, thermally stable, or high-melting additives, such as glass fibers or mineral fibers, which support ash stability. Suitable fibers that can be used in the aqueous intumescent fire protection composition according to the invention are inorganic fibers. Typical inorganic fibers are: carbide fibers, such as boron carbide fibers, silicon carbide fibers, niobium carbide fibers, etc.; nitride fibers, such as silicon nitride fibers; boron-containing fibers, such as boron fibers, boride fibers; silicon-containing fibers, such as. E.g. silicon fibers, alumina-boron-silica fibers, E-glass fibers (non-basic aluminum borates), C-glass fibers (non-basic or low-basic sodium aluminum borosilicate fibers), A-glass fibers (basic sodium silicate fibers), S-glass fibers, inorganic glass fibers, quartz fibers, etc.Glass fibers can include E-glass fibers, C-glass fibers, A-glass fibers, S-glass fibers, etc. Ceramic fibers and basalt fibers can also be used. Kevlar (para-aramid fibers) can also be used. Examples of fiber products include: Rockforce® MS603, Rockforce® MS605, CoatForce® CF30, CoatForce® CF50, FGCS 8069, FGCS ECR 416, FGCS ECR 316.

[0194] When present, the fibers are preferably present in an amount of 0.3 to 15 wt% and more preferably in an amount of 0.5 to 6 wt%, based on the total weight of the coating composition.

[0195] Suitable ash crust stabilizers or framework formers are the compounds commonly used in fire protection formulations and known to the person skilled in the art, for example expandable graphite and particulate metals such as aluminum, magnesium, iron, and zinc. The particulate metal can be in the form of a powder, platelets, flakes, fibers, filaments, and / or whiskers, with the particulate metal in the form of powder, platelets, or flakes having a particle size of <50 μm, preferably from 0.5 to 10 μm. When using the particulate metal in the form of fibers, filaments, and / or whiskers, a thickness of 0.5 to 10 μm and a length of 10 to 50 μm is preferred.Alternatively or additionally, an oxide or a compound of a metal from the group comprising titanium, aluminum, magnesium, iron, or zinc can be used as an ash crust stabilizer, in particular iron oxide, preferably iron trioxide, titanium dioxide, a borate, such as zinc borate, and / or a glass frit made of low-melting glasses with a melting temperature of preferably at or above 400°C, phosphate or sulfate glasses, melamine polyzinc sulfates, ferroglasses, or calcium borosilicates. The addition of such an ash crust stabilizer contributes to a significant stabilization of the ash crust in the event of a fire, since these additives increase the mechanical strength of the intumescent layer and / or prevent it from dripping off. Examples of such additives can also be found in US 4,442,157 A, US 3,562,197 A, GB 755,551 A, and EP 138,546 A1.

[0196] Ash crust stabilizers such as melamine phosphate or melamine borate may also be included.

[0197] For the purposes of fire protection of structural elements, especially those made of steel, it is preferred if the insulating layer is formed by chemical intumescence and is stabilized accordingly.

[0198] In a preferred embodiment of the invention, in which the insulating layer is formed by chemical intumescence, the intumescent fire protection additive comprises at least one dehydrogenation catalyst, at least one gas generator, and at least one ash crust stabilizer, in particular an oxide or compound of a metal from the group comprising titanium, aluminum, magnesium, iron, or zinc, especially titanium dioxide. This allows for particularly good fire performance.

[0199] In an even more preferred embodiment of the invention, in which the insulating layer is formed by chemical intumescence, the intumescent fire protection additive comprises at least one dehydration catalyst, at least one gas generator, at least one ash crust stabilizer, and an inorganic fiber, in particular glass fibers or mineral fibers. This improves both the fire performance and the appearance of the cured or dried coating, especially when the coating composition is applied to edges and corners.

[0200] It is sufficiently known to the person skilled in the art that the weight ratio of the four main components of the intumescent fire protection additive, carbon framework former: acid former: gas former: ash crust stabilizer, should be 0.7-1.3:2, 7-3, 7:0.7-1.3:0.7-1.3, preferably 1:3, 5:1:1.

[0201] Compound to improve microorganism resistance

[0202] A disadvantage of physically curing fire protection compounds based on aqueous dispersions is that, in addition to water, they contain a variety of compounds that promote mold growth and serve as a breeding ground for microorganisms. Furthermore, depending on the ambient conditions, it takes a certain amount of time for the applied fire protection compound to dry. The longer the drying time, the greater the likelihood that the wet coating will be attacked by microorganisms.

[0203] To improve the resistance of the aqueous fire protection composition to microbiological attack, particularly after its application to a substrate, as well as the fire protection coating produced from the fire protection composition according to the invention, it is necessary to add special compounds to protect the film applied to a substrate from microbiological attack (film preservation). The compounds optionally contained in the aqueous binder, the dispersion, for in-can preservation, to protect the aqueous product from microbiological attack (in-can preservation), are not sufficient for this purpose. Therefore, according to the invention, the fire protection composition comprises at least one compound to improve microbiological resistance.This compound is added to the aqueous fire protection composition in addition to any compounds already contained in the described dispersion for in-can preservation in order to achieve film preservation.

[0204] All biocides based on methylchloroisothioazolinone, methylisothiazolinone, benzisothiazolinone, methylisothiazolinone, 2-bromo-2-nitropropane-1,3-diol, bis(2-pyridylthio)zinc 1,1-dioxide, iodopropynyl butylcarbamate, and 2-octyl-2H-isothiazol-3-one that are commonly known to those skilled in the art can be used as compounds for improving microorganism resistance in the fire protection composition according to the invention. Examples of these are the products from Thor that are commercially available under the trade names Acticide MBS, Acticide MKE-N, Acticide OTA20, Acticide MBL, Acticide IMS2, Acticide LA1209, Acticide L14, and Acticide OTW.

[0205] According to the invention, the compound for improving microorganism resistance is present in the fire protection composition in a proportion of 0.05 wt.% to 0.3 wt.% to achieve film preservation. Preferably, the proportion of the compound for improving microorganism resistance is in a range of 0.10 wt.% to 0.25 wt.%, more preferably in a range of 0.1 wt.% to 0.20 wt.%, in each case based on the total weight of the aqueous fire protection composition.

[0206] The addition of the compound to improve microorganism resistance in an amount of more than 0.3 wt.% may result in the fire protection composition becoming subject to labelling requirements, which may make the use of the fire protection composition impossible or only possible to a limited extent in some countries or may lead to lower customer acceptance.

[0207] Furthermore, the inventors have found that in the said range, the fire performance of a fire protection coating made from the fire protection composition according to the invention is not negatively influenced.

[0208] Other additives and fillers

[0209] The following additional additives and / or fillers can be added to the aqueous fire protection composition according to the invention.

[0210] Compounds added as flame retardants include phosphate esters, halogen-containing compounds such as tri-(2-chloroisopropyl) phosphate (TCPP), tris(2-ethylhexyl) phosphate, dimethylpropanephosphonate, triethyl phosphate, and the like. Some such compounds are described, for example, in S. V. Levchik, E. D. Weil, Polym. Int. 2004, 53, 1901-1929. The flame retardants can preferably be present in an amount of 3 to 6 wt.%.

[0211] In addition to the binder composition, the fire protection compositions preferably also contain at least one pigment and / or at least one filler. However, fire protection compositions that do not contain a pigment or filler are also part of the invention.

[0212] Pigments within the meaning of the present invention are practically insoluble, finely dispersed, organic or preferably inorganic colorants within the meaning of the German standard DIN 55944. The fire protection composition preferably contains at least one inorganic pigment. Inorganic pigments are preferred, for example

[0213] White pigments such as titanium dioxide (Cl Pigment White 6), zinc white, zinc borate, pigment-grade zinc oxide, zinc sulfide, lithopone; lead white; furthermore, white fillers such as barium sulfate and CaCCh, which are also referred to as inorganic white pigments in the context of the present invention,

[0214] Black pigments, such as iron oxide black (Cl Pigment Black 11), iron manganese black, spinel black (Cl Pigment Black 7), carbon black or lamp black, color pigments, such as chromium oxide, chromium oxide hydrate green; chrome green (Cl Pigment Green 48); cobalt green (Cl Pigment Green 50); ultramarine green; cobalt blue (Cl Pigment Blue 28 and 36); ultramarine blue, iron blue (Cl Pigment Blue 27), manganese blue, ultramarine violet, cobalt violet, manganese violet, Fe3O4, iron oxide red (Cl Pigment Red 101); cadmium sulfoselenide (Cl Pigment Red 108); molybdate red (Cl

[0215] Pigment Red 104); ultramarine blue,

[0216] Iron oxide brown, mixed brown, spinel and corundum phases (Cl Pigment Brown 24, 29 and 31), chrome orange;

[0217] Iron oxide yellow (Cl Pigment Yellow 42); nickel titanium yellow (Cl Pigment Yellow 53; Cl Pigment Yellow 157 and 164); chromium titanium yellow; cadmium sulfide and cadmium zinc sulfide (Cl Pigment Yellow 37 and 35); chrome yellow (Cl Pigment Yellow 34), zinc yellow, alkaline earth chromates; Naples yellow; bismuth vanadate (Cl Pigment Yellow 184). Preferred inorganic pigments are selected from inorganic white pigments, especially titanium dioxide, barium sulfate, and CaCCh.

[0218] The fire-protection compositions according to the invention may also contain mixtures of two or more different pigments, in which case it is preferred that at least one pigment is inorganic. The pigments are typically in particulate form, i.e., in the form of particles. Pigments can be selected from raw pigments, i.e., untreated pigments such as synthesized pigments. The pigment particles can be of regular or irregular shape, for example, the particles can have a substantially spherical or needle shape.

[0219] In one embodiment of the present invention, the pigment has a pronounced uneven ratio of length to diameter with an average particle length (median, d50) in the range from 1 to 50 pm, preferably in the range from 2 to 20 pm and particularly preferably in the range from 5 to 15 pm and a ratio of the particle length to the smallest diameter of at least 2:1, preferably 10:1 to 20:1 and particularly preferably greater than 20:1. In one embodiment of the present invention, the pigment is in spherical or substantially spherical form, ie the ratio of the longest diameter to the smallest diameter is in the range from 1.0 to 2.0, preferably up to 1.5. In one embodiment of the present invention, the pigment has an average particle diameter (median, d50) in the range from 20 to 50 pm, preferably in the range from 50 to 20 pm and particularly preferably up to a maximum of 5 pm, measured e.g.using a Coulter counter or a Hegman meter.

[0220] Examples of suitable fillers are aluminosilicates such as feldspars, silicates such as kaolin, talc, mica, magnesite, alkaline earth metal carbonates such as calcium carbonate, for example in the form of calcite or chalk, magnesium carbonate, dolomite, alkaline earth metal sulfates such as calcium sulfate, silicon dioxide, attapulgite, or also glass spheres, hollow glass spheres, glass powder, expanded open- or closed-cell glass powder, perlite, basalt, pumice, etc. Finely divided fillers are naturally preferred in the coating compositions according to the invention. The fillers can be used in the form of individual components. In practice, however, filler mixtures have proven particularly effective, for example calcium carbonate / kaolin, calcium carbonate / talc. The fillers also include matting agents, which can significantly impair the surface gloss if desired.Examples of matting agents include inorganic silicates, such as the Syloid® brands from WR Grace & Company and the Acematt® brands from Evonik GmbH. Organic matting agents are available from BYK-Chemie GmbH under the Ceraflour® and Ceramat® brands, and from Deuteron GmbH under the Deuteron MK® brand.

[0221] The proportion of pigments and fillers in coating materials can be described in a conventional manner using the pigment volume concentration (PVC). The PVC describes the ratio of the volume of pigments (VP) and fillers (VF) to the total volume, consisting of the volumes of binder (VB), pigments (VP), and fillers (VF), in a dried coating in percent: PVC = (VP + VF) x 100 / (VP + VF + VB).

[0222] The fire protection compositions typically have a pigment volume concentration (PVC) of at least 5, in particular at least 10. Preferably, the PVC will not exceed a value of 60, in particular 40, and is in particular in the range from 5 to 60 or 5 to 40. However, the inventive effects of the polymer dispersions are also evident in coatings that typically have a pigment / filler content of less than 5 wt.%, based on the coating composition, and accordingly have a PVC of less than 5.

[0223] The aqueous fire protection compositions according to the invention may also contain conventional adjuvants. The conventional adjuvants depend, as is known, on the type of coating and include, but are not limited to: rheology modifiers, wetting or dispersing agents, film-forming aids, leveling agents, biocides, defoamers, and at least one intumescent filler combination containing at least melamine (blowing agent), ammonium polyphosphate (acid donor), and polyalcohol (carbon source). The latter intumescent filler combinations are generally known, for example from “Die Aktuelle-Wochenschau der GDCh - Bauen und Chemie 32 / 2011”, Rene Gries, “Fire protection - an interesting, diverse application area of ​​construction chemistry” and are commercially available, for example as Charmor™ PM40 (Perstorp AB, SE-284 80 Perstorp, Sweden), as Melafine® (OCI NV Amsterdam, NL) or as Exolit® AP 462 (Clariant, Muttenz, Switzerland).

[0224] Suitable rheology modifiers include associative thickener polymers and non-associative rheology modifiers. Suitable associative thickener polymers include anionic associated thickeners such as hydrophobically modified acrylate thickeners, also known as HASE thickeners, and nonionic associative thickeners, also known as NiSAT-type associative thickeners, including hydrophobically modified polyethylene oxide urethane rheology modifiers, also known as HEUR or PUR thickeners, or hydrophobically modified polyethylene oxides, also known as HMPE. Suitable non-associative rheology modifiers include cellulose-based thickeners, especially hydroxyethylcellulose, but also thickeners based on acrylate emulsions (ASE). Cellulose-based non-associative thickeners are preferred.The amount of thickener polymer depends on the desired viscosity profile and is often in the range of 0.05 to 2.5 wt.%, in particular 0.1 to 2 wt.% thickener, and especially 0.15 to 1.5 wt.%, based on the coating composition. Inorganic thickeners are also suitable, such as attapulgite, a hydrated magnesium aluminosilicate and a major member of the Fuller's earth family (clay minerals) with the ideal formula:

[0225] 3MgO - 1,5AL2O3- 8SiO2- 9H2O.

[0226] Fuller's earth is known as any clay material that can decolorize oil or other liquids without the use of aggressive chemical treatments. Fuller's earth typically consists of palygorskite (attapulgite) or bentonite. The highly thixotropic behavior of these attapulgites provides improved syneresis control and reduced settling without negatively affecting the leveling and film buildup of the coating.

[0227] Suitable wetting or dispersing agents are, for example, sodium polyphosphates, potassium polyphosphates or ammonium polyphosphates, alkali metal salts and ammonium salts of acrylic acid copolymers or maleic anhydride copolymers or polyphosphonates.

[0228] Solvents and plasticizers are suitable film-forming aids. In contrast to solvents, plasticizers have low volatility and preferably have a boiling point at 1013 mbar of more than 250°C, whereas solvents have higher volatility than plasticizers and preferably have a boiling point of less than 250°C at 1013 mbar. Suitable film-forming aids include, for example, white spirit, pine oil, propylene glycol, ethylene glycol, butyl glycol, butyl glycol acetate, butyl glycol diacetate, butyl diglycol, butyl carbitol, 1-methoxy-2-propanol, 2,2,2-trimethyl-1,3-pentanediol monoisobutyrate (Texanol®) and the glycol ethers and esters, commercially available, for example, from BASF SE under the names Solvenon® and Lusolvan® and from Dow under the trade name Dowanol®. The amount is preferably <10 wt.% and particularly preferably <5 wt.%, based on the total formulation. Formulation without solvent is also possible.Further formulation components for aqueous coatings are described in detail in M. Schwartz and R. Baumstark “Water-based acrylates for decorative coatings”, Curt R. Vincentz Verlag, Hanover, 2001, pp. 191-212 (ISBN 3-87870-726-6).

[0229] The fire protection composition according to the invention can comprise at least one leveling agent. The term "leveling agent" in the sense of the present invention describes a compound by means of which the viscosity of the fire protection composition is reduced. The addition of a leveling agent enables the use of very high solids contents in the fire protection composition without impairing the surface properties, in particular the surface roughness, of a coating produced from the corresponding fire protection composition. Optionally, leveling is achieved by increasing the surface tension through the leveling agent. Preferably, silicone-based compounds (PDMS polydimethylsiloxane modified), fluorocarbon-based compounds (modified fluorocarbons), acrylate-based compounds (polyacrylates), or carbohydrate-based products are used as leveling agents.Examples include the commercially available products BYK 3760, Modaflow® AQ3000, Modaflow® AQ3025, and Afcone 3034. The flow control agents can preferably be present in the fire protection composition in an amount of 0.1% to 2.0% by weight, preferably 0.3% to 1.5% by weight, based on the total weight of the fire protection composition.

[0230] Additional additives such as thickeners, rheology additives, and fillers can be added to the fire protection composition and significantly improve the storage stability of the formulation. Suitable thickeners and rheology additives are helpful in improving the hold-up (the layer thickness that can be applied with one application) in the fire protection composition. Furthermore, these additives help to significantly improve storage stability. Rheology additives such as anti-settling agents, anti-sagging agents, and thixotropic agents are preferably methyl cellulose, hydroxyethyl cellulose, carboxymethyl cellulose, hydroxypropyl cellulose, hydrophobically modified hydroxyethyl cellulose, alkali-swellable emulsions, hydrophobically modified alkali-swellable emulsions, hydrophobically modified ethoxylated urethane copolymers, hydrophobically modified cellulose ethers, hectorite clay, or attapulgite.Furthermore, organic low-shear thickeners are capable of significantly increasing holdup. Suitable associative thickener polymers include anionic associated thickeners such as hydrophobically modified acrylate thickeners, also known as HASE thickeners. Examples of commercially available thickeners are Natrosol® 250HHR, Aqualon® 9M31 F, Benton® Gel 1002v, Natrosol® Plus 330, Acrysol® TT-615, Acrysol® ASO-60ER, Attagel® 50, Rheovis® HS 1162, or Rheovis® PU 1191.

[0231] The fire protection composition according to the invention may optionally additionally contain conventional auxiliaries, such as solvents, such as xylene or toluene, or Texanol. The use of Texanol, due to its comparatively high boiling point, is helpful in lowering the evaporation point. Furthermore, the addition of a solvent is very suitable for improving the sprayability of the product, since, as is well known, the viscosity of the formulation is reduced by the addition of solvent.

[0232] Assembly

[0233] The aqueous fire protection composition according to the invention can be formulated as a single-component or multi-component system, wherein a multi-component system also includes a two-component system, which is preferred.

[0234] In a one-component system, all components of the aqueous

[0235] Binder composition contained in a single component.

[0236] In a two-component system, the components of the aqueous

[0237] The fire protection composition is divided between the two components. The components contained in the aqueous fire protection composition are divided according to their function and / or their compatibility with each other and with the compounds contained in the fire protection composition and can be contained in one or both of the two components. Furthermore, the distribution of the other additives and fillers, especially the solid components, can depend on the quantities in which they are to be included in the composition. Appropriate distribution may result in a higher proportion relative to the total composition.

[0238] In one embodiment of a preferred two-component system, the fire protection composition according to the invention is formulated such that the aqueous binder serves as the first component and the intumescent fire protection additive serves as the second component. Further possible additives can be present in both the first and second components, or in both.

[0239] In an alternative embodiment of a preferred two-component system, the fire protection composition according to the invention is formulated such that the aqueous binder serves as the first component, which additionally contains a portion of the intumescent fire protection additive, and the remaining portion of the intumescent fire protection additive serves as the second component. Other possible additives can also be contained in both the first and second components, or in both.

[0240] The fire protection composition according to the invention is particularly suitable as a coating for structural purposes, in particular as a fire protection coating, preferably as a sprayable coating for metallic and non-metallic-based substrates. The fire protection composition can be applied to surfaces such as metal, asphalt, concrete, fiberboard, stone, ceramic, minerals, wood, plastic, polymer, and glass. The fire protection composition can be applied to architectural structural components or parts of the technical building equipment, for example and not limited to beams, joists, cable ducts, ventilation pipes, water or power lines, or cladding. The fire protection composition can preferably be applied to statically loaded structural components in buildings. It can be used both indoors and outdoors.

[0241] A further subject of the present invention is therefore a coating produced from the fire protection composition according to the invention, as well as a substrate comprising a coating according to the invention or a fire protection composition according to the invention.

[0242] The fire protection composition according to the invention is used primarily in the construction sector as a coating for structural purposes, in particular fire protection coating for steel construction elements, but also for construction elements made of other materials, such as concrete or wood, as well as fire protection coating for individual cables, cable bundles, cable trays and cable ducts or other lines.

[0243] A further object of the invention is therefore the use of the fire protection composition according to the invention as a coating, in particular as a coating of metallic and / or non-metallic substrates, very particularly for construction elements or building elements made of steel, concrete, wood and other materials, such as plastics, in particular as a fire protection coating, in each case for construction purposes.

[0244] A further subject of the invention are methods for producing a fire protection coating on a surface comprising

[0245] (a) applying the fire protection composition according to the invention to the surface, and

[0246] (b) Allowing the fire protection composition to dry to produce the

[0247] coating.

[0248] The fire protection composition can be applied to surfaces and / or substrates to be coated in a conventional manner, such as by applying the paint with a brush or roller, by spraying, by dipping, by rolling, or by doctoring. The fire protection composition is preferably applied using an airless spraying process. The coating of surfaces and / or substrates is carried out by first coating the surface and / or substrate with a fire protection composition according to the invention, and then subjecting the aqueous fire protection composition to a drying step.

[0249] The substrate can be coated with a suitable primer prior to coating. This may be intended to improve the adhesion of the fire protection composition according to the invention to the substrate and / or to apply an additional corrosion-inhibiting intermediate layer.

[0250] The following examples serve to further illustrate the invention.

[0251] EXAMPLES OF IMPLEMENTATION

[0252] For the preparation of compositions according to the invention, formulations with the individual components listed in Table 1 are mixed and homogenized using a dissolver.

[0253] The following components were used to prepare the formulations according to the invention and the comparative formulations: 1 Ammonium polyphosphate of various modifications regarding water solubility

[0254] For fire tests, samples were prepared by coating a steel plate (280 mm x 280 mm x 5 mm) with the respective formulation containing the components shown in Table 1. The layer thickness of the applied formulations was 1.3 and 2.6 mm, respectively. After application, the applied layer was stored at 22 °C for at least 10 days before the fire test was carried out. The back of the steel plates was each equipped with three thermocouples, which recorded the temperature on the side facing away from the fire and over which the arithmetic mean was calculated. The samples were subjected to a fire test by installing them in the wall of an internally fired furnace. The heating rate of the furnace corresponded to the rate described in ISO 834.The time until a temperature of 538°C is reached on the back steel surface, also referred to as the "time to failure," corresponds to the value TTF (538°C / 1.3 mm) or TTF (538°C / 2.6 mm). The values ​​are shown in Table 1.

[0255] As can be seen from Table 1, the addition of fibers can significantly improve the TTF value, especially at a layer thickness of 2.6 mm (Comparative Example 1 and Example 1). The results of Examples 2 and 3 show that the addition of the fungicide has no significant negative impact on the fire performance (TTF value).

[0256] Table 1 : Components of the fire protection compositions of Comparative Example 1 and Examples 1 to 3 and results of the fire tests

Claims

PATENT CLAIMS 1. Aqueous fire protection composition comprising a polymer as aqueous binder, which has a (a) aqueous polymer latex of a film-forming carboxylated polymer; (b) 0.05 to 7.5 wt.%, based on the dry weight of the carboxylated polymer, of a branched polyetheramine polyol, dissolved in the aqueous phase of the polymer latex, wherein at least 90% of all amino groups in the branched polyetheramine polyol are tertiary amine groups, and wherein the aqueous polymer latex of the carboxylated polymer is obtainable by a free-radical emulsion polymerization of a monomer composition M, wherein the monomer composition M comprises, i) 70 wt.% to 99.95 wt.-%, based on the total weight of the monomer composition M, of one or more ethylenically unsaturated monomers M1 which are selected from Ci-C2o-alkyl esters of monoethylenically unsaturated monocarboxylic acids having 3 to 6 carbon atoms, di-Ci-C2o-alkyl esters of monoethylenically unsaturated dicarboxylic acids having 4 to 6 C atoms, Cs-C2o-cycloalkyl esters of monoethylenically unsaturated monocarboxylic acids having 3 to 6 C atoms, vinyl esters of Ci-C2o-alkanoic acids, vinyl aromatic monomers, C2-C6 monoolefins and butadiene; ii) 0.05 wt.% to 10 wt.%, based on the total weight of the monomer composition M, of one or more monoethylenically unsaturated monomers M2 selected from monoethylenically unsaturated monocarboxylic acids having 3 to 6 carbon atoms and monoethylenically unsaturated dicarboxylic acids having 4 to 6 carbon atoms; iii) 0 wt.% to 20 wt.-%, based on the total weight of the monomer composition M, of one or more non-ionic monomers M3 which are different from the monomers M1, at least one intumescent fire protection additive and at least one compound for improving the resistance to microorganisms, wherein the proportion of the compound for improving the resistance to microorganisms is from 0.05 to 0.30 wt. %, based on the total weight of the aqueous fire protection composition.

2. An aqueous fire retardant composition according to claim 1, wherein the intumescent fire retardant additive further comprises inorganic fibers.

3. Aqueous fire protection composition according to claim 2, wherein the proportion of inorganic fibers is from 0.3 to 15 wt.%, based on the total weight of the aqueous fire protection composition.

4. Aqueous fire protection composition according to one of the preceding claims, wherein the proportion of the aqueous binder is 20 wt.% to 45 wt.%, based on the total weight of the fire protection composition.

5. Aqueous fire protection composition according to one of the preceding Claims, wherein the proportion of the intumescent fire protection additive is 30 wt.% to 80 wt.%, based on the total weight of the aqueous Fire protection composition.

6. Aqueous fire protection composition according to any one of the preceding claims, wherein the intumescent fire protection additive comprises at least one dehydrogenation catalyst and at least one gas generator.

7. An aqueous fire retardant composition according to claim 6, wherein the intumescent fire retardant additive further comprises a carbon source.

8. An aqueous fire protection composition according to any one of claims 6 or 7, wherein the intumescent fire protection additive further comprises an ash crust stabilizer.

9. Aqueous fire protection composition according to any one of the preceding claims, wherein the compound for improving microorganism resistance comprises biocides based on methylchloroisothioazolinone, methylisothiazolinone, benzisothiazolinone, methylisothiazolinone, 2-bromo-2-nitropropane-1,3-diol, bis-(2- Pyridylthio)zinc-1,1-dioxide, iodopropynyl butylcarbamate and 2-octyl-2H-isothiazol-3-one.

10. Aqueous fire protection composition according to one of the preceding claims, wherein the fire protection composition is formulated as a two- or multi-component system.

11. Fire protection coating made from an aqueous fire protection composition according to one of claims 1 to 10.

12. Fire protection coating according to claim 11, wherein the aqueous fire protection composition is applied to a substrate, preferably to a metallic substrate, by means of an airless spraying process.

13. A substrate comprising a fire protection coating according to one of claims 11 or 12.

14. Use of an aqueous fire protection composition according to any one of claims 1 to 10 for fire protection.

15. Use of an aqueous fire protection composition according to any one of claims 1 to 10 for coating components.

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