INORGANIC BINDER COMPOSITION COMPLETING A COPOLYMER

Description

[0001] The present invention relates to compositions comprising at least one inorganic binder and at least one specific water-soluble copolymer. Furthermore, a process for producing this composition is disclosed. A further aspect of the present invention is the use of the specific copolymer in a composition according to the invention as a rheological additive.

[0002] Water-soluble, thickening polymers are used in many areas of technology, for example in cosmetics, in food, for the production of cleaning agents, printing inks, emulsion paints, in oil production or in construction chemistry.

[0003] Water-soluble non-ionic derivatives of polysaccharides, especially cellulose and starch derivatives, are commonly used in aqueous building material mixtures to prevent the undesirable evaporation of water required for hydration and workability, as well as to control segregation, sedimentation and bleeding (settlement of water on the surface) of the system.

[0004] According to Ullmann's Encyclopedia of Technical Chemistry (4th edition, Volume 9, pages 208-210, Verlag Chemie Weinheim), the most commonly used rheological additives are synthetically produced non-ionic cellulose and starch derivatives such as methylcellulose (MC), hydroxyethylcellulose (HEC), methylhydroxyethylcellulose (MHEC), and methylhydroxypropylcellulose (MHPC). However, microbially produced polysaccharides such as welan gum and diutan gum, as well as naturally occurring extractively isolated polysaccharides (hydrocolloids), such as alginates, xanthans, carrageenans, galactomannans, etc., are also used according to the state of the art to control the rheology of waterborne building materials and coating systems.

[0005] Many chemically distinct classes of polymers are known that can be used as rheological additives in aqueous inorganic building material mixtures. An important class of stabilizing polymers are so-called hydrophobically associating polymers. These are defined by those skilled in the art as water-soluble polymers that have hydrophobic groups at their sides or ends, such as longer alkyl chains. In aqueous solution, such hydrophobic groups can associate with themselves or with other substances containing hydrophobic groups. This forms an associative network that stabilizes the medium.

[0006] EP 705 854 A1, DE 100 37 629 A1, and DE 10 2004 032 304 A1 disclose water-soluble, hydrophobically associating copolymers and their use, for example, in the field of construction chemistry. The described copolymers comprise acidic monomers such as acrylic acid, vinylsulfonic acid, acrylamidomethylpropanesulfonic acid, basic monomers such as acrylamide, dimethylacrylamide, or monomers containing cationic groups, such as monomers containing ammonium groups. Such monomers impart water solubility to the polymers. As hydrophobically associating monomers, the disclosed copolymers each contain monomers of the following type: H 2 C=C(R x< )-COO-(-CH 2 -CH 2 -O-) q -R y or H 2 C=C(R ×< )-O-(-CH 2 -CH 2 -O-) q -R y< where R x< typically stands for H or CH 3 and R y< stands for a larger hydrocarbon radical, typically for hydrocarbon radicals with 8 to 40 carbon atoms.For example, longer alkyl groups or a tristyrylphenyl group are mentioned in the documents.

[0007] Furthermore, US Pat. No. 8,362,180 relates to water-soluble copolymers containing hydrophobically associating monomers. The monomers comprise an ethylenically unsaturated group and a polyether group with a block structure consisting of a hydrophilic polyalkylene oxide block consisting essentially of ethylene oxide groups and a terminal, hydrophobic polyalkylene oxide block consisting of alkylene oxides having at least 4 carbon atoms, preferably at least 5 carbon atoms.

[0008] Furthermore, the use of these hydrophobically associating copolymers in aqueous building material compositions is disclosed.

[0009] WO 2004 / 099100 discloses cement additives comprising a polycarboxylic acid polymer with a polyether side chain exhibiting an EO / PO / EO triblock structure. The EO blocks can have 1 to 200 repeating units, while the PO block is an alkylene oxide unit with 3 to 18 carbon atoms and 1 to 50 repeating units. The examples describe polymers with a weight-average molecular weight of 8,500 to 40,500 g / mol. The description discloses a weight-average molecular weight of the polycarboxylic acid polymers of no more than 1,000,000 g / mol. The cement additives are said to achieve high water reduction and improve viscosity.

[0010] Although many hydrophobically associating copolymers known from the state of the art are very good stabilizers for aqueous inorganic building material compositions, they have the disadvantage of impairing the flowability of the aqueous inorganic building material compositions.

[0011] The present invention was therefore based on the object of providing inorganic binder compositions which show the lowest possible tendency to sedimentation, segregation and bleeding and at the same time have very good flow properties.

[0012] This task was solved by a composition comprising (α) at ​​least one inorganic binder (β) at least one water-soluble copolymer based on (a) 0.1 to 20% by weight of at least one monomer of the formula (I), H 2 C=C(R 1< )-R 2< O-(-CH 2 -CH 2 -O-) k -(CH 2 -CH(R 3< )-O-) 1 -(-CH 2 -CH 2 -O-) m -R 4< (I) where the units -(-CH 2 -CH 2 -O-) k , -(-CH 2 -CH(R 3< )-O-) l and -(-CH 2 -CH 2 -O-) m are arranged in block structure in the order shown in formula (I) and the radicals have the following meanings: k: is a number from 10 to 150; I: is a number from 5 to 25; m: is a number from 1 to 15; R 1< : is H or methyl; R 2< : is independently a single bond or a divalent linking group selected from the group consisting of -(C n H 2n )- and -O-(C n' H 2n' )- and -C(O)-O-(C n" H 2n" )-, where n, n' and n" are a natural number from 1 to 6;R 3< : is a hydrocarbon radical having at least 2 carbon atoms or an ether group of the general formula -CH 2 -OR 3'< , where R 3'< is a hydrocarbon radical having at least 2 carbon atoms and where R 3< within the group -(-CH 2 -CH(R 3< )-O-) l can be the same or different; preferably with the proviso that the sum of the carbon atoms of all hydrocarbon radicals R 3< within the group -(-CH 2 -CH(R 3< )-O-) l is in the range from 14 to 50; R 4< : is independently H or a hydrocarbon radical having 1 to 4 carbon atoms and (b) 25 to 99.9 wt.% of at least one monoethylenically unsaturated, hydrophilic monomer (b) different from monomer (a), where the wt.% are in each case based on the total amount of all monomers in the copolymer and the at least one copolymer has a molecular weight average M of 1,500,000 to 30,000,000 g / mol, which is determined according to the Mark-Houwink relationship (1); M = η K 1 / α where K = 0.0049, α = 0.8 and [ n ] represent the intrinsic viscosity.

[0013] Surprisingly, it has been found that the copolymers not only fully solve the task at hand, but can also often be used in lower dosages compared to the state of the art.

[0014] In particular, the composition according to the invention comprises, based on its dry mass, at least 20 wt.%, preferably at least 40 wt.%, in particular from 30 to 99.9995 and particularly preferably from 35 to 55 wt.% of the at least one inorganic binder and 0.0005 to 5 wt.%, preferably 0.0005 to 2 wt.%, particularly preferably 0.001 to 1 wt.% of the at least one copolymer.

[0015] In a preferred embodiment, these are copolymers in which the radical k in monomer (a) according to formula (I) is a number from 23 to 26.

[0016] In a further preferred embodiment, the copolymers are those in which the radical I in monomer (a) according to formula (I) I is a number from 8.5 to 17.25.

[0017] In a preferred embodiment, the total sum of monomers (a) and (b) in the copolymer is 100 wt.%.

[0018] Preferably, the monomer (a) is exclusively a monomer of the general formula (I) as described above.

[0019] The following is detailed regarding the invention: The copolymers of component (β) are water-soluble copolymers containing hydrophobic groups. In aqueous compositions, the hydrophobic groups can associate with themselves or with the hydrophobic groups of other substances, thickening the aqueous composition through these interactions.

[0020] Those skilled in the art are aware that the solubility of hydrophobically associating copolymers in water can depend to a greater or lesser extent on the pH value, depending on the type of monomers used. The reference point for assessing water solubility should therefore always be the pH value desired for the particular application of the copolymer.

[0021] For the purposes of the present application, "water-soluble copolymer" means copolymers which have a solubility in water at 20 °C and atmospheric pressure and the pH of the respective composition according to the invention considered of at least 1 gram per liter of water, in particular at least 10 grams per liter of water and particularly preferably at least 100 grams per liter of water.

[0022] The copolymer comprises at least one monoethylenically unsaturated monomer (a) which imparts hydrophobic associating properties to the copolymer.

[0023] The at least one monomer (a) is a monomer of the general formula (I) H 2 C=C(R 1< )-R 2< -O-(-CH 2 -CH 2 -O-) k -(-CH 2 -CH(R 3< )-O-) l -(-CH 2 -CH 2 -O-) m -R 4< (I).

[0024] In the monomers (a) of the general formula (I), an ethylenic group H 2 C=C(R 1< )- is linked via a divalent linking group -R 2< -O- to a polyalkyleneoxy radical having a block structure -(-CH 2 -CH 2 -O-) k -(-CH 2 -CH(R 3< )-O-) l -(-CH 2 -CH 2 -O-) m R 4<, where the blocks -(-CH 2 -CH 2 -O-) k , -(-CH 2 -CH(R 3< )-O-) l and -(-CH 2 -CH 2 -O-) m are arranged in the order shown in formula (I). The monomers (a) have either a terminal OH group or a terminal ether group OR 4<.

[0025] In the above formula, R 1< represents H or a methyl group. R 1< is preferably H.

[0026] R 2< represents a single bond or a divalent linking group selected from the group consisting of -(C n H 2n )-, -O-(C n' H 2n' )- and -C(O)-O-(C n" H 2n" )-. In the formulas mentioned, n, n' and n" stand for a natural number from 1 to 6. In other words, the linking group is a straight-chain or branched aliphatic hydrocarbon group having 1 to 6 carbon atoms, which is linked to the ethylenic group H 2 C=C(R 1< )- either directly or via an ether group -O- or a carboxyl ester group -C(O)-O-. The groups -(C n H 2n )-, -(C n' H 2n' )- and -(C n" H 2n" )- are preferably linear aliphatic hydrocarbon groups.

[0027] The group R 2< = -(C n H 2n )- is preferably a group selected from - CH 2 -, -CH 2 -CH 2 - and -CH 2 -CH 2 -CH 2 -, particularly preferably a methylene group -CH 2 -.

[0028] The group R 2< = -O-(C n' H 2n' )- is preferably a group selected from - O-CH 2 -CH 2 -, -O-CH 2 -CH 2 -CH 2 - and -O-CH 2 -CH 2 -CH 2 -CH 2 -, particularly preferably -O-CH 2 -CH 2 -CH 2 -CH 2 -.

[0029] The group R 2< = -C(O)-O-(C n" H 2n" )- is preferably a group selected from -C(O)-O-CH 2 -, -C(O)-O-CH 2 -CH 2 - and -C(O)-O-CH 2 -CH 2 -CH 2 -, particularly preferably -C(O)-O-CH 2 -CH 2 -.

[0030] Particularly preferably, the group R 2< is a group -O-(C n' H 2n' )-.

[0031] Furthermore, R 2< is particularly preferably a group selected from -CH 2 -or -O-CH 2 -CH 2 -CH 2 -CH 2 - or -C(O)-O-CH 2 -CH 2 -, very particularly preferably -O-CH 2 -CH 2 -CH 2 -CH 2 -.

[0032] The monomers (a) further comprise a polyalkyleneoxy radical consisting of the units -(-CH 2 -CH 2 -O-) k , -(-CH 2 -CH(R 3< )-O-) l , and -(-CH 2 -CH 2 -O-) m , wherein the units are arranged in a block structure in the order shown in formula (I). The transition between the blocks can be abrupt or continuous.

[0033] The number of ethyleneoxy units k is a number from 10 to 150, preferably from 12 to 50, particularly preferably from 15 to 35 and particularly preferably from 20 to 30.

[0034] The number of ethyleneoxy units k is most preferably a number from 23 to 26. The numbers mentioned are always mean values ​​of distributions.

[0035] In the second block -(-CH 2 -CH(R 3< )-O-) l - the radicals R 3< independently of one another represent hydrocarbon radicals having at least 2 carbon atoms, preferably having 2 to 14 carbon atoms, particularly preferably having 2 to 4 and most preferably having 2 or 3 carbon atoms. This can be an aliphatic and / or aromatic, linear or branched carbon radical. These are preferably aliphatic radicals. Particularly preferably it is an aliphatic, unbranched hydrocarbon radical having 2 or 3 carbon atoms. The said block is preferably a polybutyleneoxy block or a polypentyleneoxy block.

[0036] Examples of suitable radicals R 3< include ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl or n-decyl, n-dodecyl, n-tetradecyl and phenyl.

[0037] Examples of suitable R 3< radicals include ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, or n-decyl, as well as phenyl. Examples of preferred radicals include n-propyl, n-butyl, and n-pentyl; particularly preferred is an ethyl radical or an n-propyl radical.

[0038] The radicals R 3< can also be ether groups of the general formula -CH 2 -OR 3'<, where R 3'< is an aliphatic and / or aromatic, linear or branched hydrocarbon radical having at least 2 carbon atoms, preferably 2 to 10 carbon atoms, and particularly preferably at least 3 carbon atoms. Examples of radicals R 3'< include n-propyl, n-butyl, n-pentyl, n-hexyl, 2-ethylhexyl, n-heptyl, n-octyl, n-nonyl, n-decyl, or phenyl.

[0039] Examples of radicals R 3'< include n-propyl, n-butyl, n-pentyl, n-hexyl, 2-ethylhexyl, n-heptyl, n-octyl, n-nonyl, n-decyl, n-dodecyl, n-tetradecyl or phenyl.

[0040] The block -(-CH 2 -CH(R 3< )-O-) l - is therefore a block consisting of alkyleneoxy units having at least 4 carbon atoms, preferably having 4 or 5 carbon atoms and / or glycidyl ethers having an ether group of at least 2, preferably at least 3 carbon atoms. Preferred radicals R 3< are the hydrocarbon radicals mentioned; the building blocks of the second block are particularly preferably alkyleneoxy units comprising at least 4 carbon atoms, such as butyleneoxy and pentyleneoxy units or units of higher alkylene oxides, very particularly preferably butylene oxide or pentyleneoxy units.

[0041] It is clear to those skilled in the art in the field of polyalkylene oxides that the orientation of the hydrocarbon radicals R 3< can depend on the conditions during the alkoxylation, for example, on the catalyst chosen for the alkoxylation. The alkyleneoxy groups can therefore be incorporated into the monomer either in the orientation -(-CH 2 -CH(R 3< )-O-)- or in the inverse orientation -(-CH(R 3< )-CH 2 -O-)-. The representation in formula (I) should therefore not be considered limited to a specific orientation of the group R 3<.

[0042] The number of alkyleneoxy units I is a number from 5 to 25, in particular from 6 to 23, particularly preferably from 7 to 20, most preferably from 8.5 to 17.25. The sum of the carbon atoms in all hydrocarbon radicals R 3< within the group -(-CH 2 -CH(R 3< )-O-) 1 is preferably from 14 to 50, preferably from 18 to 40, particularly preferably from 25.5 to 34.5. If the radicals R 3< are an ether group - CH 2 -OR 3'< , the proviso applies that the sum of the hydrocarbon radicals of R 3'< within the group -(-CH 2 -CH(R 3'< )-O-) 1 is from 14 to 50, preferably from 18 to 40, particularly preferably from 25.5 to 34.5, the carbon atom of the linking -CH 2 -O- group in -CH 2 -OR 3'< not being taken into account.

[0043] A preferred embodiment relates to a copolymer described above comprising a monomer (a), wherein R 3< ethyl and I is a number from 7.5 to 25, preferably from 12.75 to 25, particularly preferably from 13 to 23, most preferably from 12.75 to 17.25, for example 14, 16 or 22.

[0044] In a preferred embodiment, the number of alkyleneoxy units I is a number from 8.5 to 17.25, in particular with the proviso that the sum of the carbon atoms in all hydrocarbon radicals R 3< is in the range from 25.5 to 34.5. If the radicals R 3< are an ether group -CH 2 -OR 3'<, the proviso applies in particular that the sum of the hydrocarbon radicals R 3'< is in the range from 25.5 to 34.5, the carbon atom of the linking -CH 2 -O- group in -CH 2 -OR 3'< being disregarded. A preferred embodiment relates to a copolymer described above comprising a monomer (a), where R 3< is ethyl and I is a number from 12.75 to 17.25, in particular from 13 to 17, for example 14 or 16.A further preferred embodiment relates to a copolymer described above comprising a monomer (a), wherein R 3 is n-propyl and I is a number from 8.5 to 11.5, preferably from 9 to 11, for example 10 or 11. As already mentioned, the numbers mentioned are average values ​​of distributions.

[0045] The block -(-CH 2 -CH 2 -O-) m is a polyethyleneoxy block. The number of ethyleneoxy units m is a number from 1 to 15, preferably from 0.1 to 10, more preferably from 0.1 to 5, especially preferably from 0.5 to 5, and most preferably from 2 to 5. Again, these numbers are averages of distributions.

[0046] The radical R 4< is H or a preferably aliphatic hydrocarbon radical having 1 to 4 carbon atoms. R 4< is preferably H, methyl, or ethyl, more preferably H or methyl, and most preferably H.

[0047] It is clear to a person skilled in the art in the field of polyalkyleneoxy block copolymers that the transition between the blocks can be abrupt or continuous, depending on the type of preparation. In the case of a continuous transition, there is still a transition zone between the blocks, which comprises monomers of both blocks. If the block boundary is set at the middle of the transition zone, the first block - (-CH 2 -CH 2 -O-) k can accordingly still have small amounts of -(-CH 2 -CH(R 3< )-O-)- units and the second block -(-CH 2 -CH(R 3< )-O-) l can accordingly still have small amounts of -(-CH 2 -CH 2 -O-)- units, although these units are not distributed randomly over the block but are arranged in the aforementioned transition zone. In particular, the third block (-CH 2 -CH 2 -O-) m can have small amounts of -(-CH 2 -CH(R 3< )-O-)- units.

[0048] Block structure in the sense of the present invention means that the blocks are made up of at least 85 mol%, preferably at least 90 mol%, particularly preferably at least 95 mol%, based on the total amount of the respective block, of the corresponding units. This means that the blocks may have small amounts of other units (in particular other polyalkyleneoxy units) in addition to the corresponding units. In particular, the polyethyleneoxy block -(-CH 2 -CH 2 -O-) m contains at least 85 mol%, preferably at least 90 mol%, based on the total amount of the block, of the unit (-CH 2 -CH 2 -O-). In particular, the polyethyleneoxy block -(-CH 2 -CH 2 -O-) m consists of 85 to 95 mol% of the unit (-CH 2 -CH 2 -O-) and of 5 to 15 mol% of the unit -(-CH 2 -CH(R 3< )-O-).

[0049] It is preferably a copolymer in which the radicals in monomer (a) according to formula (I) have the following meanings: k: is a number from 15 to 35, preferably from 20 to 28, in particular from 23 to 26; l: is a number from 5 to 25, preferably from 5 to 23, in particular from 5 to 20; m: is a number from 1 to 15, preferably from 0.5 to 10; R 1< : is H; R 2< : is a divalent, linking group -O-(C n' H 2n' )-, where n' is 4; R 3< : is, independently of one another, a hydrocarbon radical having 2 carbon atoms; in particular ethyl; R 4< : is H.

[0050] It is preferably a copolymer in which the radicals in monomer (a) according to formula (I) have the following meanings: k: is a number from 15 to 35, preferably from 20 to 28, particularly preferably from 23 to 26; l: is a number from 7.5 to 25, preferably from 10 to 25, particularly preferably from 12.75 to 25; particularly preferably from 13 to 23, for example 14, 16 or 22; m: is a number from 1 to 15, preferably from 0.5 to 10; R 1< : is H; R 2< : is a divalent, linking group -O-(C n' H 2n' )-, where n' is 4; R 3< : is, independently of one another, a hydrocarbon radical having 2 carbon atoms; in particular ethyl; R 4< : is H.

[0051] It is preferably a copolymer in which the radicals in monomer (a) according to formula (I) have the following meanings: k: is a number from 15 to 35, preferably from 20 to 28, preferably from 23 to 26; l: is a number from 7.5 to 25, preferably from 10 to 25, particularly preferably from 12.75 to 25; especially preferably from 13 to 23, for example 14, 16 or 22; m: is a number from 0.1 to 10, preferably from 0.5 to 10, particularly preferably from 2 to 5; R 1< : is H; R 2< : is a divalent, linking group -O-(C n' H 2n' )-, where n' is 4; R 3< : is, independently of one another, a hydrocarbon radical having 2 carbon atoms; in particular ethyl; R 4< : is H.

[0052] It is preferably a copolymer in which the radicals in monomer (a) according to formula (I) have the following meanings: k: is a number from 23 to 26; l: is a number from 12.75 to 17.25; m: is a number from 1 to 15; preferably from 0.5 to 10; R 1< : is H; R 2< : is a divalent linking group -O-(C n' H 2n' )-, where n' is 4; R 3< : is, independently of one another, a hydrocarbon radical having 2 carbon atoms; in particular ethyl; R 4< : is H.

[0053] In particular, it is a copolymer in which the radicals in monomer (a) according to formula (I) have the following meanings: k: is a number from 23 to 26; l: is a number from 8.5 to 11.5; m: is a number from 1 to 15, preferably from 0.5 to 10; R 1< : is H; R 2< : is a divalent linking group -O-(C n' H 2n' )-, where n' is 4; R 3< : is a hydrocarbon radical having 3 carbon atoms, in particular n-propyl; R 4< : is H.

[0054] In a particularly preferred embodiment, these are copolymers whose radicals in monomer (a) according to formula (I) have the following meaning: k: is a number from 23 to 26; l: is a number from 12.75 to 17.25; m: is a number from 2 to 5; R 1< : is H; R 2< : is a divalent linking group -O-(C n' H 2n' )-, where n' is 4, R 3< : is a hydrocarbon radical having 2 carbon atoms; R 4< : is H.

[0055] The invention further preferably relates to compositions which comprise a copolymer in which, in addition to the monomer (a) of the formula (I), a monomer (d) of the formula (III) is present H 2 C=C(R 1< )-RL< O-(-CH 2 -CH 2 -O-) k -(-CH 2 -CH(R 3< )-O-) l -H (III) where the radicals R 1< , R 2< , R 3< , k and l have the meanings defined above; Furthermore, it is preferably a copolymer in which the weight ratio of the monomer (a) of the formula (I) to the monomer (d) of the formula (III) is in the range from 19:1 to 1:19, preferably in the range from 9:1 to 1:9.

[0056] The present application further provides a process for producing a composition according to the invention, wherein the monomer (a) of the general formula (I) is produced by a process comprising the following steps: a) reacting a monoethylenically unsaturated alcohol A1 of the general formula (II) H 2 C=C(R 1< )-R 2< -OH (II), with ethylene oxide, where the radicals R 1< and R 2< have the meanings defined above; with addition of an alkaline catalyst K1 containing KOMe and / or NaOMe; to obtain an alkoxylated alcohol A2; b) reacting the alkoxylated alcohol A2 with at least one alkylene oxide Z of the formula (Z) where R 3< has the meaning defined above; with addition of an alkaline catalyst K2; where the concentration of potassium ions in the reaction in step b) is less than or equal to 0.9 mol% based on the alcohol A2 used; and where the reaction in step b) is carried out at a temperature of less than or equal to 135°C, where an alkoxylated alcohol A3 is obtained according to the formula (III), H 2 C=C(R 1< )-R 2< -O-(-CH 2 -CH 2 -O-) k -(-CH 2 -CH(R 3< )-O-) l -H (III) where the radicals R 1< , R 2< , R 3< , k and l have the meanings defined above; c) reacting the alcohol A3 with ethylene oxide; whereby an alkoxylated alcohol A4 is obtained which corresponds to the monomer (a) according to formula (I) with R 4< = H and m = 1 to 15;d) optionally etherifying the alkoxylated alcohol A4 with a compound R 4< -X, where R 4< is a hydrocarbon radical having 1 to 4 carbon atoms and X is a leaving group, preferably selected from the group of Cl, Br, I, -O-SO 2 -CH 3 (mesylate), -O-SO 2 -CF 3 (triflate) and -O-SO 2 -OR 4<; whereby a monomer (a) according to formula (I) with R 4< = hydrocarbon radical having 1 to 4 carbon atoms is obtained; radical polymerization of the resulting monomer (a) with a monomer (b), whereby the water-soluble copolymer (β) is obtained and bringing the water-soluble copolymer (β) into contact with the at least one inorganic binder.

[0057] Step a) of the process according to the invention comprises the reaction of a monoethylenically unsaturated alcohol A1 with ethylene oxide with addition of an alkaline catalyst K1 containing KOMe (potassium methoxide) and / or NaOMe (sodium methoxide), whereby an alkoxylated alcohol A2 is obtained.

[0058] The preferred conditions (e.g. pressure and / or temperature ranges) mentioned below for the reactions according to step a), b), c) and optionally d) mean that the respective step is carried out wholly or partly under the stated conditions.

[0059] Preferably, step a) first comprises reacting the monoethylenically unsaturated alcohol A1 with the alkaline catalyst K1. Typically, the alcohol A1 used as starting material is admixed with an alkaline catalyst K1 in a pressure reactor. By reducing the pressure to typically less than 100 mbar, preferably in the range from 50 to 100 mbar, and / or increasing the temperature, typically to 30 to 150°C, any water and / or low-boiling components still present in the mixture can be removed. The alcohol is then present essentially as the corresponding alkoxide. The reaction mixture is then typically treated with an inert gas (e.g., nitrogen).

[0060] Further preferably, step a) first comprises the reaction of the monoethylenically unsaturated alcohol A1 with the alkaline catalyst K1. Typically, for this purpose, the alcohol A1 used as starting material is admixed with an alkaline catalyst K1 in a pressure reactor. By reducing the pressure to typically less than 100 mbar, preferably in the range from 30 to 100 mbar, and / or increasing the temperature, typically to 30 to 150°C, any water and / or low boilers still present in the mixture can be removed. The alcohol is then present essentially as the corresponding alkoxide. The reaction mixture is then typically treated with an inert gas (e.g., nitrogen).

[0061] Preferably, step a) comprises the addition of ethylene oxide to the above-described mixture of alcohol A1 with the alkaline catalyst K1 (as described above). After the addition of ethylene oxide is complete, the reaction mixture is typically allowed to continue reacting. The addition and / or subsequent reaction typically takes place over a period of 2 to 36 hours, preferably 5 to 24 hours, particularly preferably 5 to 15 hours, and most preferably 5 to 10 hours.

[0062] Further preferably, step a) comprises the addition of ethylene oxide to the above-described mixture of alcohol A1 with the alkaline catalyst K1 (as described above). After the addition of ethylene oxide has ended, the reaction mixture is typically allowed to continue reacting. The continued reaction typically takes place over a period of 0.1 to 1 h. The addition, including optional depressurization (intermediate reduction of the pressure from, for example, 6 to 3 bar absolute) and including the continued reaction, takes place, for example, over a period of 2 to 36 h, preferably 5 to 24 h, particularly preferably 5 to 15 h, and most preferably 5 to 10 h.

[0063] Step a) typically takes place at temperatures of 60 to 180°C, preferably from 130 to 150°C, particularly preferably from 140 to 150°C. In particular, step a) comprises the addition of the ethylene oxide to the mixture of alcohol A1 with the alkaline catalyst K1 at a temperature of 60 to 180°C, preferably from 130 to 150°C, particularly preferably from 140 to 150°C.

[0064] The ethylene oxide is preferably added to the mixture of alcohol A1 and alkaline catalyst K1 at a pressure in the range of 1 to 7 bar, preferably in the range of 1 to 5 bar. To comply with safety requirements, the addition in step a) is typically carried out at a pressure in the range of 1 to 3.1 bar. In particular, the addition of ethylene oxide and / or the post-reaction are carried out under the above-mentioned conditions.

[0065] Furthermore, the addition of the ethylene oxide to the mixture of alcohol A1 and alkaline catalyst K1 is preferably carried out at a pressure in the range from 1 to 7 bar, preferably in the range from 1 to 6 bar. In order to meet safety requirements, the addition in step a) is typically carried out at a pressure in the range from 1 to 4 bar, preferably 1 to 3.9 bar, particularly preferably 1 to 3.1 bar, or in a further embodiment of the invention, from 3 to 6 bar. In particular, the addition of ethylene oxide and / or the post-reaction are carried out under the above-mentioned conditions.

[0066] Preferably, step a) comprises the addition of the ethylene oxide to a mixture of alcohol A1 and alkaline catalyst K1 over a period of less than or equal to 36 hours, preferably less than or equal to 32 hours, particularly preferably over a period of 2 to 32 hours, and at a pressure of less than or equal to 5 bar, preferably 1 to 4 bar, particularly preferably 1 to 3.9 bar, and especially 1 to 3.1 bar. In particular, the above-specified period comprises the addition of ethylene oxide and / or the post-reaction.

[0067] In particular, the reaction of a monoethylenically unsaturated alcohol A1 with ethylene oxide with the addition of an alkaline catalyst K1 containing KOMe (potassium methoxide) and / or NaOMe (sodium methoxide) according to step a) of the process according to the invention can be carried out in one or more ethoxylation steps. A process as described above is preferred, wherein step a) comprises the following steps: reaction of the monoethylenically unsaturated alcohol A1 with the alkaline catalyst K1, reaction of the mixture of alcohol A1 and catalyst K1 with a portion of the ethylene oxide, in particular 10 to 50% by weight, in particular 10 to 30% by weight, of the total amount of ethylene oxide, an intermediate step comprising a rest phase and / or pressure release, and reaction with the remaining portion of the ethylene oxide.

[0068] Further preferred is a process as described above, wherein step a) comprises the following steps: Reaction of the monoethylenically unsaturated alcohol A1 with the alkaline catalyst K1, reaction of the mixture of alcohol A1 and catalyst K1 with a portion of the ethylene oxide, in particular 50 to 98% by weight, in particular 80 to 98% by weight, of the total amount of ethylene oxide, a step for removing low boilers with pressure relief to a pressure of less than 100 mbar, preferably 50 to 100 mbar and / or increasing the temperature, typically in the range from 30 to 150°C, reaction of the resulting ethoxylation product with the alkaline catalyst K1 and reaction of the remaining portion of the ethylene oxide with the mixture of ethoxylation product and alkaline catalyst K1.

[0069] Further preferred is a process as described above, wherein step a) comprises the following steps: Reaction of the monoethylenically unsaturated alcohol A1 with the alkaline catalyst K1, reaction of the mixture of alcohol A1 and catalyst K1 with a portion of the ethylene oxide, in particular 50 to 98% by weight, in particular 80 to 98% by weight, of the total amount of ethylene oxide, a step for removing low boilers with pressure relief to a pressure of less than 100 mbar, preferably 30 to 100 mbar and / or increasing the temperature, typically in the range from 30 to 150°C, reaction of the resulting ethoxylation product with the alkaline catalyst K1 and reaction of the remaining portion of the ethylene oxide with the mixture of ethoxylation product and alkaline catalyst K1.

[0070] The alkaline catalyst K1 contains in particular 10 to 100 wt. % KOMe and / or NaOMe, preferably 20 to 90 wt. %. In addition to KOMe and / or NaOMe, the catalyst K1 may contain further alkaline compounds and / or a solvent (in particular a C1 to C6 alcohol). For example, it may contain a compound selected from alkali metal hydroxides, alkaline earth metal hydroxides, alkali metal alkoxides (C2 to C6 potassium alkoxides, C2 to C6 sodium alkoxides, preferably ethanolate), alkaline earth metal alkoxides (in particular C1 to C6 alkoxides, preferably methoxide and / or ethanolate). Preferably, in addition to KOMe and / or NaOMe, the catalyst K1 contains at least one further alkaline compound selected from sodium hydroxide and potassium hydroxide. In another preferred embodiment, the alkaline catalyst K1 consists of KOMe or a mixture of KOMe and methanol (MeOH). Typically, a solution of 20 to 50 wt. % KOMe in methanol (MeOH) can be used.

[0071] In a further preferred embodiment, the alkaline catalyst K1 consists of NaOMe or a mixture of NaOMe and methanol (MeOH). Typically, a solution of 20 to 50 wt. % NaOMe in methanol (MeOH) can be used.

[0072] In a further preferred embodiment, the alkaline catalyst K1 consists of a mixture of KOMe and NaOMe or a solution of KOMe and NaOME in methanol.

[0073] If KOMe is used as the basic catalyst K1 in the reaction in step a), it is advantageous to use K1 in an amount such that an upper limit of 2,500 ppm (approximately 0.4 mol%) of KOMe relative to the alcohol A1 used is maintained in order to avoid decomposition of the monoethylenically unsaturated alcohol A1. Preferably, the concentration of potassium ions in step a) is less than or equal to 0.4 mol% based on the total amount of alcohol A1 used, particularly preferably 0.1 to 0.4 mol%.

[0074] If KOMe is added in such an amount that the concentration exceeds 0.9 mol% based on the ethoxylated alcohol A2 (product of process step a), KOMe must be completely or partially removed before step b) in order to obtain a potassium ion concentration of less than 0.9 mol% in process step b). This can be achieved, for example, by isolating and optionally purifying the ethoxylated alcohol A2 after step a).

[0075] In a further preferred embodiment, KOMe is used in an amount such that the concentration of potassium ions after the reaction in step a) is already less than or equal to 0.9 mol% based on A2.

[0076] Step b) of the process according to the invention comprises the reaction of the ethoxylated alcohol A2 with at least one alkylene oxide Z with addition of an alkaline catalyst K2, whereby an alkoxylated alcohol A3 is obtained which corresponds to the monomer (a) according to formula (III) H 2 C=C(R 1< )-R 2< -O-(-CH 2 -CH 2 -O-) k -(-CH 2 -CH(R 3< )-O-) l -R 4< (III) with R 4< = H.

[0077] Preferably, step b) first comprises reacting the ethoxylated alcohol A2 with the alkaline catalyst K2. Typically, the alkaline catalyst K2 is added to the alcohol A2 in a pressure reactor. By reducing the pressure to typically less than 100 mbar, preferably in the range from 50 to 100 mbar, and / or increasing the temperature, typically in the range from 30 to 150°C, any water and / or low boilers still present in the mixture can be removed. The alcohol is then present essentially as the corresponding alkoxide. The reaction mixture is then typically treated with an inert gas (e.g., nitrogen).

[0078] Further preferably, step b) first comprises reacting the ethoxylated alcohol A2 with the alkaline catalyst K2. Typically, for this purpose, the alcohol A2 is admixed with the alkaline catalyst K2 in a pressure reactor. By reducing the pressure to typically less than 100 mbar, preferably in the range from 30 to 100 mbar, and / or increasing the temperature, typically in the range from 30 to 150°C, any water and / or low boilers still present in the mixture can be removed. The alcohol is then present essentially as the corresponding alkoxide. The reaction mixture is then typically treated with an inert gas (e.g., nitrogen).

[0079] Preferably, step b) comprises the addition of at least one alkylene oxide Z to the above-described mixture of alcohol A2 with alkaline catalyst K2. After the addition of the alkylene oxide Z is complete, the reaction mixture is typically allowed to continue reacting. The addition and / or subsequent reaction typically takes place over a period of 2 to 36 hours, preferably 5 to 24 hours, particularly preferably 5 to 20 hours, and most preferably 5 to 15 hours.

[0080] Preferably, step b) comprises the addition of at least one alkylene oxide Z to the above-described mixture of alcohol A2 with alkaline catalyst K2. After the addition of the alkylene oxide Z is complete, the reaction mixture is typically allowed to continue reacting. The addition, including optional depressurization and including the subsequent reaction, typically takes place over a period of 2 to 36 hours, preferably 5 to 30 hours, particularly preferably 10 to 28 hours, and particularly preferably 11 to 24 hours.

[0081] According to the invention, the concentration of potassium ions in the reaction in step b) is less than or equal to 0.9 mol%, preferably less than 0.9 mol%, preferably from 0.01 to 0.9 mol%, particularly preferably from 0.1 to 0.6 mol%, based on the alcohol A2 used. Preferably, in the preparation of monomer (a), the concentration of potassium ions in the reaction in step b) is from 0.01 to 0.5 mol%, based on the alcohol A2 used.

[0082] In a particularly preferred embodiment, the concentration of potassium ions in the reaction in step b) is 0.1 to 0.5 mol% and the reaction in step b) is carried out at temperatures of 120 to 130°C.

[0083] The alkaline catalyst K2 preferably contains at least one alkaline compound selected from alkali metal hydroxides, alkaline earth metal hydroxides, alkali metal alkoxides (in particular C1 to C6 alkoxides, preferably methoxide and / or ethanolate), alkaline earth metal alkoxides (in particular C1 to C6 alkoxides, preferably methoxide and / or ethanolate). The catalyst preferably contains at least one basic sodium compound, in particular selected from NaOH, NaOMe, and NaOEt, particularly preferably NaOMe or NaOH. A mixture of the aforementioned alkaline compounds can be used as catalyst K2; preferably, the catalyst K2 consists of one of the aforementioned basic compounds or mixtures of the aforementioned alkaline compounds. Frequently, an aqueous solution of the alkaline compounds is used. In another preferred embodiment, the alkaline catalyst K2 consists of NaOMe or a mixture of NaOMe and methanol.Typically, a solution of 20 to 50 wt.% NaOMe in methanol can be used. Preferably, catalyst K2 does not contain KOMe.

[0084] Preferably, in the preparation in step b), a catalyst K2 containing at least one basic sodium compound, in particular selected from NaOH, NaOMe, and NaOEt, is used, wherein the concentration of sodium ions in the reaction in step b) is 3.5 to 12 mol%, preferably 3.5 to 7 mol%, particularly preferably 4 to 5.5 mol%, based on the alcohol A2 used.

[0085] According to the invention, the reaction in step b) is carried out at a temperature of less than or equal to 135°C. The reaction in step b) is preferably carried out at temperatures of 60 to 135°C, preferably at 100 to 135°C, particularly preferably at 120 to 130°C. In particular, step b) comprises the addition of the at least one alkylene oxide Z to a mixture of alcohol A2 with alkaline catalyst K2 at a temperature of less than or equal to 135°C, preferably at temperatures of 60 to 135°C, particularly preferably at 100 to 135°C, particularly preferably at 120 to 135°C.

[0086] Preferably, step b) is carried out at a pressure in the range from 1 to 3.1 bar, preferably from 1 to 2.1 bar. To meet safety requirements, the reaction in step b) is preferably carried out at a pressure in the range of less than or equal to 3.1 bar (preferably 1 to 3.1 bar) if R 3< represents a hydrocarbon radical having 2 carbon atoms, or at a pressure of less than or equal to 2.1 bar, preferably 1 to 2.1 bar, if R 3< represents a hydrocarbon radical having more than 2 carbon atoms.

[0087] Furthermore, step b) is preferably carried out at a pressure in the range from 1 to 6 bar, preferably from 1 to 3.1 bar, particularly preferably from 1 to 2.1 bar. The reaction in step b) is preferably carried out at a pressure in the range from 1 to 6 bar, preferably from 1 to 3.1 bar, particularly preferably from 4 to 6 bar, if R 3< represents a hydrocarbon radical having 2 carbon atoms. In particular, the addition of alkylene oxide Z and / or the subsequent reaction are carried out at the abovementioned pressures.

[0088] In particular, it is a copolymer wherein R 3< represents a hydrocarbon radical having 2 carbon atoms and, in the preparation of monomer (a), step b) is carried out at a pressure in the range from 1 to 3.1 bar; or wherein R 3< represents a hydrocarbon radical having at least 3 carbon atoms, preferably having 3 carbon atoms, and, in the preparation of monomer (a), step b) is carried out at a pressure of 1 to 2.1 bar.

[0089] In particular, the addition of alkylene oxide Z and / or the post-reaction are carried out at the above-mentioned pressure. Preferably, step b) comprises the addition of the at least one alkylene oxide Z to a mixture of alcohol A2 and alkaline catalyst K2 at a pressure in the range of less than or equal to 3.1 bar (preferably 1 to 3.1 bar) if R3< represents a hydrocarbon radical having 2 carbon atoms, or at a pressure of less than or equal to 2.1 bar, preferably 1 to 2.1 bar, if R3< represents a hydrocarbon radical having at least 3 carbon atoms.

[0090] Preferably, step b) comprises the addition of the at least one alkylene oxide Z to a mixture of alcohol A2 with alkaline catalyst K2 over a period of less than or equal to 36 h, preferably less than or equal to 32 h, particularly preferably over a period of 2 to 32 h, very particularly preferably over a period of 5 to 24 h, and at a pressure of less than or equal to 3.1 bar, preferably at 1 to 2.1 bar, further preferably at the abovementioned pressures.

[0091] Further preferably, step b) comprises the addition of the at least one alkylene oxide Z to a mixture of alcohol A2 with alkaline catalyst K2 over a period of less than or equal to 36 h, preferably less than or equal to 32 h, particularly preferably over a period of 2 to 32 h, very particularly preferably over a period of 11 to 24 h, and at a pressure of less than or equal to 3.1 bar, further preferably at the abovementioned pressures.

[0092] Particularly preferably, step b) is carried out at a pressure in the range of 1 to 3.1 bar, preferably at the above-mentioned pressures and at a temperature of 120 to 130°C.

[0093] The process according to the invention further comprises step c), wherein the alkoxylated alcohol A3 is reacted with ethylene oxide; whereby an alkoxylated alcohol A4 is obtained which corresponds to the monomer (a) according to the formula (I) with R 4< = H and m = 1 to 15, preferably 1 to 10, particularly preferably 0.1 to 10, in particular 0.1 to 5, particularly preferably 0.5 to 5 and very particularly preferably 0.5 to 2.5.

[0094] Step c) is carried out in particular without further addition of an alkaline catalyst. Step c) is carried out in particular at a pressure in the range of 1 to 7 bar, preferably 1 to 5 bar, and a temperature in the range of 60 to 140°C, preferably 120 to 140°C, particularly preferably 125 to 135°C. The ethoxylation in step c) is carried out in particular over a period of 0.5 to 7 hours, in particular 0.5 to 5 hours, preferably 0.5 to 4 hours.

[0095] Step c) is further preferably carried out without further addition of an alkaline catalyst. Step c) is carried out in particular at a pressure in the range of 1 to 7 bar, preferably 1 to 6 bar, and a temperature in the range of 60 to 140°C, preferably 120 to 140°C, particularly preferably 120 to 135°C. The ethoxylation in step c) is carried out in particular over a period of 0.5 to 7 hours, in particular 1 to 5 hours, preferably 1 to 4 hours.

[0096] Preferably, step c) comprises the addition of ethylene oxide to the reaction mixture after step b) containing the alkoxylated alcohol A3 of formula (III) without further workup and / or pressure release. After the addition of the ethylene oxide is complete, the reaction mixture is typically allowed to react. The addition and / or reaction typically takes place over a period of 0.5 to 10 hours, in particular 0.5 to 7 hours, in particular 0.5 to 5 hours, preferably 0.5 to 4 hours.

[0097] Further preferably, step c) comprises the addition of ethylene oxide to the reaction mixture after step b) containing the alkoxylated alcohol A3 of formula (III) without further workup and / or pressure release. After the addition of the ethylene oxide is complete, the reaction mixture is typically allowed to react. The addition, including optional pressure release and the subsequent reaction, typically takes place over a period of 0.5 to 10 hours, in particular 2 to 10 hours, in particular 4 to 8 hours.

[0098] The process according to the invention may optionally comprise step d), wherein the alkoxylated alcohol A4 is etherified with a compound R 4< -X, wherein X is a leaving group, preferably selected from Cl, Br, I, -O-SO 2 -CH 3 (mesylate), -O-SO 2 -CF 3 (triflate) or -O-SO 2 -CR 4<.

[0099] If the alkoxylated alcohol A4 of formula (I) with a terminal OH group (i.e., R 4< = H) is to be etherified, this can also be done with conventional alkylating agents known in principle to the person skilled in the art, for example, alkyl sulfates and / or alkyl halides. Typically, the compound R 4< -X can be an alkyl halide. Dimethyl sulfate or diethyl sulfate, in particular, can also be used for etherification. Etherification is only one option, which can be selected by the person skilled in the art depending on the desired properties of the copolymer.

[0100] In addition to the monomers (a), the copolymer comprises at least one different, monoethylenically unsaturated, hydrophilic monomer (b). Of course, mixtures of several different hydrophilic monomers (b) can also be used.

[0101] The hydrophilic monomers (b) comprise, in addition to an ethylenic group, one or more hydrophilic groups. Due to their hydrophilicity, these groups impart sufficient water solubility to the copolymer. These hydrophilic groups are, in particular, functional groups comprising O and / or N atoms. They may also comprise heteroatoms, particularly S and / or P atoms.

[0102] The monomers (b) are particularly preferably miscible with water in any ratio; however, for practicing the invention, it is sufficient that the hydrophobically associating copolymer has the water solubility mentioned above. The solubility of the monomers (b) in water at room temperature should preferably be at least 100 g / l, in particular at least 200 g / l, and particularly preferably at least 500 g / l.

[0103] Examples of suitable functional groups include carbonyl groups >C=O, ether groups -O-, in particular polyethyleneoxy groups -(CH 2 -CH 2 -O-) n -, where n is preferably a number from 1 to 200, hydroxy groups -OH, ester groups -C(O)O-, primary, secondary or tertiary amino groups, ammonium groups, amide groups -C(O)-NH-, carboxamide groups -C(O)-NH 2 or acidic groups such as carboxyl groups -COOH, sulfonic acid groups -SO 3 H, phosphonic acid groups -PO 3 H 2 or phosphoric acid groups -OP(OH) 3 .

[0104] Examples of preferred functional groups include hydroxy groups -OH, carboxyl groups -COOH, sulfonic acid groups -SO 3 H, carboxamide groups -C(O)-NH 2 , amide groups -C(O)-NH- and polyethyleneoxy groups -(CH 2 -CH 2 -O-) n -H, where n preferably stands for a number from 1 to 200.

[0105] The functional groups can be directly attached to the ethylenic group or can be linked to the ethylenic group via one or more linking hydrocarbon groups.

[0106] The hydrophilic monomers (b) are preferably monomers of the general formula H 2 C=C(R 5< )R 6< (IV) , where R 5< is H or methyl and R 6< is a hydrophilic group or a group comprising one or more hydrophilic groups.

[0107] The groups R 6< are groups which contain heteroatoms in such an amount that the water solubility defined above is achieved.

[0108] Examples of suitable monomers (b) include monomers comprising acidic groups, for example monomers comprising -COOH groups such as acrylic acid or methacrylic acid, crotonic acid, itaconic acid, maleic acid or fumaric acid, monomers comprising sulfonic acid groups such as vinylsulfonic acid, allylsulfonic acid, sulfoethyl methacrylate, 2-acrylamido-2-methylpropanesulfonic acid (AMPS), 2-methacrylamido-2-methylpropanesulfonic acid, 2-acrylamidobutanesulfonic acid, 3-acrylamido-3-methylbutanesulfonic acid or 2-acrylamido-2,4,4-trimethylpentanesulfonic acid or monomers comprising phosphonic acid groups such as vinylphosphonic acid, allylphosphonic acid, N-(meth)acrylamidoalkylphosphonic acids or (meth)acryloyloxyalkylphosphonic acids.

[0109] Also worth mentioning are acrylamide and methacrylamide, as well as their derivatives, such as N-methyl(meth)acrylamide, N,N'-dimethyl(meth)acrylamide, and N-methylolacrylamide; N-vinyl derivatives such as N-vinylformamide, N-vinylacetamide, N-vinylpyrrolidone, or N-vinylcaprolactam; and vinyl esters such as vinyl formate or vinyl acetate. N-vinyl derivatives can be hydrolyzed to vinylamine units after polymerization, and vinyl esters to vinyl alcohol units.

[0110] Further examples include monomers comprising hydroxyl and / or ether groups, such as, for example, hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, allyl alcohol, hydroxyvinyl ethyl ether, hydroxyvinyl propyl ether, hydroxyvinyl butyl ether or compounds of the formula H 2 C=C(R 1< )-O-(-CH 2 -CH(R 7< )-O-) b -R 8< (V) where R 1< is as defined above and b is a number from 2 to 200, preferably 2 to 100. The radicals R 7< are, independently of one another, H, methyl or ethyl, preferably H or methyl, with the proviso that at least 50 mol% of the radicals R 7< are H. Preferably, at least 75 mol% of the R 7< radicals are H, more preferably at least 90 mol%, and most preferably exclusively H. The R 8< radical is H, methyl, or ethyl, preferably H or methyl. The individual alkyleneoxy units can be arranged randomly or blockwise.In a block copolymer, the transition between the blocks can be abrupt or gradual.

[0111] Further suitable hydrophilic monomers (b) are described in WO 2011 / 133527 (page 15, lines 1-23).

[0112] The above-mentioned hydrophilic monomers can, of course, be used not only in the acid or base form shown, but also in the form of corresponding salts. It is also possible to convert acidic or basic groups into corresponding salts after polymer formation. The corresponding salts are preferably alkali metal salts or ammonium salts, particularly preferably organic ammonium salts, and especially preferably water-soluble organic ammonium salts.

[0113] Preferred is a copolymer in which at least one of the monomers (b) is a monomer comprising acidic groups, wherein the acidic groups are at least one group selected from the group consisting of -COOH, -SO 3 H and -PO 3 H, and salts thereof.

[0114] Preferably, at least one of the monomers (b) is a monomer selected from the group of (meth)acrylic acid, vinylsulfonic acid, allylsulfonic acid, sulfoethyl methacrylate and 2-acrylamido-2-methylpropanesulfonic acid (AMPS), particularly preferably acrylic acid and / or APMS or salts thereof.

[0115] Preferably, it is a copolymer which comprises at least two different monoethylenically unsaturated, hydrophilic monomers (b), and which are at least one neutral hydrophilic monomer (b1), and at least one hydrophilic anionic monomer (b2) which comprises at least one acidic group selected from the group of -COOH, -SO 3 H and -PO 3 H 2 and their salts.

[0116] Examples of suitable monomers (b1) include acrylamide and methacrylamide, preferably acrylamide and derivatives thereof, such as N-methyl(meth)acrylamide, N,N'-dimethyl(meth)acrylamide, and N-methylolacrylamide. Also suitable are N-vinyl derivatives such as N-vinylformamide, N-vinylacetamide, N-vinylpyrrolidone, or N-vinylcaprolactam. Also suitable are monomers containing OH groups, such as hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, allyl alcohol, hydroxyvinyl ethyl ether, hydroxyvinyl propyl ether, or hydroxyvinyl butyl ether. The monomer (b1) in the copolymer is preferably acrylamide or derivatives thereof, particularly preferably acrylamide.

[0117] Examples of anionic monomers (b2) include acrylic acid or methacrylic acid, crotonic acid, itaconic acid, maleic acid or fumaric acid, monomers comprising sulfonic acid groups such as vinylsulfonic acid, allylsulfonic acid, 2-acrylamido-2-methylpropanesulfonic acid (AMPS), 2-methacrylamido-2-methylpropanesulfonic acid, 2-acrylamidobutanesulfonic acid, 3-acrylamido-3-methylbutanesulfonic acid or 2-acrylamido-2,4,4-trimethylpentanesulfonic acid or monomers comprising phosphonic acid groups such as vinylphosphonic acid, allylphosphonic acid, N-(meth)acrylamidoalkylphosphonic acids or (meth)acryloyloxyalkylphosphonic acids.

[0118] Examples of preferred anionic monomers (b2) include acrylic acid, vinylsulfonic acid, allylsulfonic acid, 2-acrylamido-2-methylpropanesulfonic acid (AMPS), 2-acrylamidobutanesulfonic acid, 3-acrylamido-3-methylbutanesulfonic acid and 2-acrylamido-2,4,4-trimethylpentanesulfonic acid, very particular preference being given to 2-acrylamido-2-methylpropanesulfonic acid (AMPS).

[0119] It is preferably a copolymer which comprises acrylamide as monomer (b1) and a monomer comprising acidic groups as monomer (b2).

[0120] It is preferably a copolymer which comprises acrylamide as monomer (b1) and a monomer comprising acidic groups as monomer (b2), wherein the acidic group is -SO 3 H. It is particularly preferred to be a copolymer which comprises acrylamide as monomer (b1) and 2-acrylamido-2-methylpropanesulfonic acid (AMPS) as monomer (b2).

[0121] It is preferably a copolymer which comprises acrylamide as monomer (b1) and acrylic acid as monomer (b2).

[0122] Furthermore, it is preferably a copolymer which comprises acrylamide as monomer (b1) and at least two further monomers (b2) comprising different acidic groups. Particularly preferred is a copolymer which comprises acrylamide as monomer (b1) and, as monomer (b2) comprising acidic groups, a monomer comprising the -SO 3 H group and a monomer comprising the -COOH group.

[0123] Furthermore, it is preferably a copolymer comprising acrylamide as monomer (b1), 2-acrylamido-2-methylpropanesulfonic acid (AMPS) as monomer (b2), and a monomer comprising the -COOH group. Furthermore, it is preferably a copolymer comprising acrylamide as monomer (b1), 2-acrylamido-2-methylpropanesulfonic acid (AMPS) as monomer (b2), and acrylic acid.

[0124] The amount of monomers (b) in the copolymer is 25 to 99.9 wt.% based on the total amount of all monomers in the copolymer, preferably 25 to 99.5 wt.%. The exact amount depends on the type and intended use of the hydrophobically associating copolymers and is determined accordingly by the person skilled in the art.

[0125] Preferably, the at least one copolymer is a copolymer based on at least one monomer (a) of the formula (I), as well as acrylamide as neutral hydrophilic monomer (b1), and acrylamido-2-methylpropanesulfonic acid (AMPS) as anionic hydrophilic monomer (b2).

[0126] Particularly preferably, the at least one copolymer comprises 0.5 to 15 wt.% of at least one hydrophobically associating monomer (a), and 19.5 to 80 wt.% of acrylamide as neutral hydrophilic monomer (b1), and 19.5 to 80 wt.% of acrylamido-2-methylpropanesulfonic acid (AMPS) as anionic hydrophilic monomer (b2),

[0127] Most preferably, the at least one copolymer comprises 1 to 7.5 wt.% of at least one hydrophobically associating monomer (a), and 45 to 55 wt.% of acrylamide as neutral hydrophilic monomer (b1), and 44 to 54 wt.% of acrylamido-2-methylpropanesulfonic acid (AMPS) as anionic hydrophilic monomer (b2),

[0128] In a preferred embodiment, component (β) additionally comprises (c) at least one nonionic, non-polymerizable surface-active component. In particular, this can be at least one nonionic surfactant. However, anionic and cationic surfactants are also suitable, provided they do not participate in the polymerization reaction.

[0129] Preferably, (c) is at least one non-ionic surfactant.

[0130] They can in particular be surfactants, preferably non-ionic surfactants of the general formula R 10< -Y', where R 10< is a hydrocarbon radical having 8 to 32, preferably 10 to 20 and particularly preferably 12 to 18 carbon atoms and Y' is a hydrophilic group, preferably a non-ionic hydrophilic group, in particular a polyalkoxy group.

[0131] The non-ionic surfactant is preferably an ethoxylated long-chain, aliphatic alcohol with 10 to 20 carbon atoms, which may optionally contain aromatic moieties.

[0132] Examples include: C12-C14 fatty alcohol ethoxylates, C16-C18 fatty alcohol ethoxylates, C13 oxo alcohol ethoxylates, C10 oxo alcohol ethoxylates, C13-C15 oxo alcohol ethoxylates, C10 Guerbet alcohol ethoxylates, and alkylphenol ethoxylates. Compounds containing 5 to 20 ethyleneoxy units, preferably 8 to 18 ethyleneoxy units, have proven particularly useful. Optionally, small amounts of higher alkyleneoxy units, in particular propyleneoxy and / or butyleneoxy units, may also be present, although the amount of ethyleneoxy units should generally be at least 80 mol% based on all alkyleneoxy units.

[0133] Particularly suitable surfactants are those selected from the group of ethoxylated alkylphenols, ethoxylated, saturated iso-C13 alcohols and / or ethoxylated C10 Guerbet alcohols, wherein in each case 5 to 20 ethyleneoxy units, preferably 8 to 18 ethyleneoxy units are present in the alkoxy radicals.

[0134] The copolymers can be prepared by radical polymerization of the monomers (a) and (b) by methods known in principle to those skilled in the art, for example by bulk, solution, gel, emulsion, dispersion, or suspension polymerization, preferably in the aqueous phase. The polymerization is preferably carried out in the presence of at least one surface-active component (c).

[0135] The present invention relates to a process for producing a composition described above, wherein, to produce the copolymer, at least one monomer (a) and at least one hydrophilic monomer (b) are subjected to aqueous solution polymerization, and the resulting water-soluble copolymer (β) is contacted with the at least one inorganic binder. The solution polymerization is preferably carried out in the presence of at least one surface-active component (c).

[0136] With regard to the process for preparing the copolymer, the preferred embodiments described above in connection with the copolymers apply.

[0137] One aspect of the present invention is a process for preparing the copolymer, wherein the solution polymerization is carried out at a pH of 5.0 to 9.

[0138] The monomers (a) of formula (I) used are prepared by the preparation process described above by multi-stage alkoxylation of alcohols (II), optionally followed by etherification. With regard to the process for preparing monomer (a), the preferred embodiments described above in connection with the copolymers apply.

[0139] In a preferred embodiment, the copolymer is prepared by gel polymerization in the aqueous phase, provided all monomers used have sufficient water solubility. For the purposes of the present invention, gel polymerization is a special case of solution polymerization and is therefore encompassed by this term. For gel polymerization, a mixture of the monomers, initiators and other auxiliaries is first prepared with water or an aqueous solvent mixture. Suitable aqueous solvent mixtures comprise water and water-miscible organic solvents, the proportion of water generally being at least 50% by weight, preferably at least 80% by weight and particularly preferably at least 90% by weight. Organic solvents that should be mentioned in particular are water-miscible alcohols such as methanol, ethanol or propanol.Acidic monomers can be completely or partially neutralized before polymerization.

[0140] The concentration of all components except the solvents is usually 25 to 60 wt.%, preferably 30 to 50 wt.%.

[0141] The mixture is then photochemically and / or thermally polymerized, preferably at -5°C to 50°C. If thermal polymerization is used, preference is given to using polymerization initiators that start at comparatively low temperatures, such as redox initiators. Thermal polymerization can be carried out at room temperature or by heating the mixture, preferably to temperatures not exceeding 50°C. Photochemical polymerization is usually carried out at temperatures of -5 to 10°C. Photochemical and thermal polymerization can be combined particularly advantageously by adding both thermal and photochemical polymerization initiators to the mixture. Polymerization is initially initiated photochemically at low temperatures, preferably -5 to +10°C.The released reaction heat heats the mixture, which also initiates thermal polymerization. This combination allows a conversion of more than 99% to be achieved.

[0142] Gel polymerization is generally performed without stirring. It can be performed batchwise by irradiating and / or heating the mixture in a suitable container at a layer thickness of 2 to 20 cm. Polymerization produces a solid gel. Polymerization can also occur continuously. For this purpose, a polymerization apparatus is used, which has a conveyor belt for receiving the mixture to be polymerized. The conveyor belt is equipped with devices for heating or irradiating with UV radiation. The mixture is then poured onto one end of the belt using a suitable device. During transport in the direction of the belt, the mixture polymerizes, and the solid gel can be removed from the other end.

[0143] After polymerization, the gel is crushed and dried. Drying should preferably take place at temperatures below 100°C. To prevent sticking, a suitable release agent can be used for this step. The copolymer is obtained as a powder.

[0144] Further details on carrying out gel polymerization are disclosed, for example, in DE 10 2004 032 304 A1, sections

[0037] to

[0041] .

[0145] Copolymers in the form of alkali-soluble, aqueous dispersions can preferably be prepared by emulsion polymerization. The implementation of emulsion polymerization using hydrophobically associating monomers is disclosed, for example, in WO 2009 / 019225, page 5, line 16 to page 8, line 13.

[0146] The copolymers preferably have an average molecular weight M of 2,000,000 to 30,000,000 g / mol, furthermore 3,000,000 to 25,000,000 g / mol, particularly preferably 5,000,000 g / mol to 20,000,000 g / mol and in particular 6,000,000 g / mol to 16,000,000 g / mol.

[0147] In a preferred embodiment, the inorganic binder is at least one selected from the group consisting of calcium sulfate n-hydrate, Portland cement, white cement, calcium aluminate cement, calcium sulfoaluminate cement, geopolymer, and latently hydraulic or pozzolanic binders such as fly ash, metakaolin, silica fume, and granulated blast furnace slag. Cement based on Portland cement, calcium sulfate hemihydrate, calcium sulfate anhydrite, and calcium aluminate cement are particularly preferred.

[0148] The composition according to the invention can in particular be powdered mixtures which are subsequently mixed with water.

[0149] In a further preferred embodiment, the composition according to the invention comprises an inorganic filler. The inorganic filler can preferably be at least one selected from the group consisting of quartz sand, quartz flour, limestone, barite, calcite, dolomite, talc, kaolin, mica, and chalk.

[0150] In a specific embodiment, the composition according to the invention consists, based on its dry mass, of at least 80 wt.%, in particular at least 90 wt.%, and particularly preferably more than 95 wt.% of an inorganic binder and an inorganic filler.

[0151] In a particularly preferred embodiment, the composition according to the invention is a factory-made dry mortar, in particular masonry mortar, plaster mortar, mortar for thermal insulation composite systems, renovation plasters, joint mortar, tile adhesive, thin-bed mortar, screed mortar, grouting mortar, injection mortar, levelling compounds, sealing slurries or lining mortar.

[0152] The constant striving for greater rationalization and improved product quality has meant that in the construction sector, mortar for a wide variety of applications is practically no longer mixed on site from the raw materials. This task is now largely carried out by the building materials industry in the factory, and the ready-to-use mixes are made available as so-called factory-mixed mortar. Ready-made mixtures that are made workable on site solely by adding water and mixing are referred to as factory-mixed mortar, in particular as factory-mixed dry mortar, in accordance with DIN 18557. Such mortar systems can fulfil a wide variety of building physics tasks. Depending on the task, further additives or admixtures are mixed with the binder in order to adapt the factory-mixed dry mortar to the specific application. These can be, for example:These can be shrinkage reducers, expansion agents, accelerators, retarders, dispersants, defoamers, air entraining agents and corrosion inhibitors.

[0153] In a particular embodiment, the composition according to the invention can also be a self-leveling leveling compound.

[0154] In particular, the composition according to the invention can thus be in the form of a dry mortar. The present application also encompasses a process for producing the composition according to the invention, wherein the at least one copolymer is brought into contact with the at least one inorganic binder and optionally other components by mixing. In particular, the copolymer is in the form of a powder.

[0155] For dry mortar applications, the copolymers are preferably used in powder form. It is preferred that the size distribution of the particles is selected such that the average particle diameter is less than 100 µm and the proportion of particles with a particle diameter greater than 200 µm is less than 2 wt.%. Preference is given to powders whose average particle diameter is less than 60 µm and the proportion of particles with a particle diameter greater than 120 µm is less than 2 wt.%. Particular preference is given to powders whose average particle diameter is less than 50 µm and the proportion of particles with a particle diameter greater than 100 µm is less than 2 wt.%. The particle diameter of the copolymers in powder form can be brought to the preferred size distributions, for example, by grinding.

[0156] In a preferred embodiment, the inorganic binder can be calcium sulfate n-hydrate (n=0 to 2), hereinafter also referred to as gypsum. The term "gypsum" is used synonymously with calcium sulfate in this context, whereby calcium sulfate can exist in its various anhydrous and hydrated forms, with and without water of crystallization. Natural gypsum essentially comprises calcium sulfate dihydrate ("dihydrate"). The natural, anhydrous form of calcium sulfate is encompassed by the term "anhydrite." In addition to its natural forms, calcium sulfate is a typical by-product of industrial processes, which is then referred to as "synthetic gypsum." A typical example of synthetic gypsum from industrial processes is flue gas desulfurization. However, synthetic gypsum can also be a by-product of phosphoric acid or hydrofluoric acid production processes.Typical gypsum (CaSO 4 × 2 H 2 O) can be calcined by separating the water of crystallization. The products of a wide variety of calcination processes are α- or β-hemihydrate. β-hemihydrate results from rapid heating in open vessels, with simultaneous rapid evaporation of water to form cavities. α-hemihydrate is produced by dehydrating gypsum in closed autoclaves. The crystal form in this case is relatively dense, which is why this binder requires less water for liquefaction than β-hemihydrate. On the other hand, hemihydrate rehydrates with water to form dihydrate crystals. The hydration of gypsum typically takes several minutes to several hours, resulting in a shorter processing time compared to cements, which require several hours to days for complete hydration.These properties make gypsum a viable alternative to cement as a binding agent in a wide variety of applications. Furthermore, cured gypsum products exhibit pronounced hardness and compressive strength.

[0157] Beta-hemihydrate is chosen for a wide variety of applications because it is more readily available and offers numerous economic advantages. However, these advantages are partially offset by the fact that beta-hemihydrate requires more water during processing to achieve flowable suspensions. Furthermore, the dried gypsum products made from this material tend to be somewhat weak due to residual water remaining in the crystal matrix during curing. For this reason, corresponding products exhibit lower hardness than gypsum products prepared with smaller amounts of mixing water.

[0158] Therefore, for the purposes of the present invention, calcium sulfate n-hydrate is particularly preferably β-calcium sulfate hemihydrate. β-calcium sulfate hemihydrate is particularly suitable for use in gypsum-based flow screed.

[0159] Furthermore, the inorganic binder can preferably be a geopolymer. Geopolymers are inorganic binder systems based on reactive, water-insoluble compounds based on SiO 2 in combination with Al 2 O 3 , which harden in an aqueous alkaline medium. Specific geopolymer compositions are described, for example, in US 4,349,386, WO 85 / 03699 and US 4,472,199. Microsilica, metakaolin, aluminosilicates, fly ash, activated clay, pozzolans or mixtures thereof can be used as the reactive oxide or oxide mixture. The alkaline medium for activating the binder usually consists of aqueous solutions of alkali metal carbonates, alkali metal fluorides, alkali metal hydroxides, alkali metal aluminates and / or alkali metal silicates such as soluble water glass.Compared to Portland cement, geopolymers can be more cost-effective and more resistant, particularly to acids, and have a more favorable CO2 emission balance.

[0160] The composition according to the invention may, in particular, also comprise a binder mixture. In the present context, this refers to mixtures of at least two binders selected from the group consisting of cement, pozzolanic and / or latently hydraulic binders, white cement, special cement, calcium aluminate cement, calcium sulfoaluminate cement, geopolymer, and various hydrous and anhydrous calcium sulfates.

[0161] The composition according to the invention can be in dry form within the scope of the present invention, which means that it has a water content according to Karl Fischer of less than 5% by weight, preferably less than 1% by weight and particularly preferably less than 0.1% by weight.

[0162] It is preferred if the composition according to the invention has an average particle size between 0.1 and 1000 µm, particularly preferably between 1 and 200 µm. The particle size is determined by laser diffractometry.

[0163] The present application further relates to the use of the copolymer of component (β) in a composition according to the invention as a rheological additive. In particular, for reducing segregation, sedimentation, and bleeding of the composition.

[0164] The following examples are intended to explain the invention in more detail. Examples Production of monomer M1:

[0165] 44.1 g of hydroxybutyl vinyl ether were initially charged into a 1 L stainless steel stirred autoclave. 3.12 g of KOMe (32% in MeOH) were then added, and the methanol was removed at 80 °C and approximately 30 mbar. The reactor was then heated to 140 °C, purged with nitrogen, and a nitrogen pre-pressure of 1.0 bar was set. 368 g of ethylene oxide (EO) were then added over a period of approximately 3 h. After a half-hour post-reaction at 140 °C, the reactor was cooled to 125 °C, and a total of 392 g of pentene oxide (PeO) were added over a period of 3.5 h. The post-reaction ran overnight.

[0166] A hydroxybutyl vinyl ether alkoxylate with 22 EO units and 12 PeO units (monomer M1) was obtained. The product had an OH number of 31.9 mg KOH / g (theory: 26.5 mg KOH / g). The OH number was determined using the acetic anhydride (ESA) method. Production of monomer M2:

[0167] In a 2-liter pressure autoclave equipped with an anchor stirrer, 135.3 g (1.16 mol) of hydroxybutyl vinyl ether (HBVE) (stabilized with 100 ppm potassium hydroxide (KOH)) were placed, and the stirrer was turned on. 1.06 g of potassium methoxide (KOMe) solution (32% KOMe in methanol (MeOH), corresponding to 0.0048 mol potassium) was added, and the stirred vessel was evacuated to a pressure of less than 10 mbar, heated to 80°C, and operated for 70 minutes at 80°C and a pressure of less than 10 mbar. MeOH was distilled off.

[0168] In an alternative procedure, the potassium methoxide (KOMe) solution (32% KOMe in methanol (MeOH)) was added, and the stirred vessel was evacuated to a pressure of 10–20 mbar, heated to 65°C, and operated for 70 min at 65°C and a pressure of 10–20 mbar. MeOH was distilled off.

[0169] The vessel was purged three times with N 2 (nitrogen). The vessel was then tested for pressure tightness, set to 0.5 bar gauge pressure (1.5 bar absolute), and heated to 120°C. The pressure was released to 1 bar absolute, and 1126 g (25.6 mol) of ethylene oxide (EO) were added until p max reached 3.9 bar absolute and T max reached 150°C. After adding 300 g of EO, the addition was discontinued (approximately 3 h after the start), followed by a 30-minute delay and a release to 1.3 bar absolute. The remaining EO was then added. The addition of EO, including the release, took a total of 10 h.

[0170] The mixture was stirred until constant pressure was reached at approximately 145-150°C (1 h), cooled to 100°C and freed from low boilers at a pressure of less than 10 mbar for 1 h.

[0171] A hydroxybutyl vinyl ether alkoxylate with 22 EO units was obtained.

[0172] In a 2 l pressure autoclave equipped with an anchor stirrer, 588.6 g (0.543 mol) of hydroxybutyl vinyl ether alkoxylate containing 22 EO units were placed, and the stirrer was switched on. Then, 2.39 g of 50% NaOH solution (0.030 mol NaOH, 1.19 g NaOH) were added, a vacuum of <10 mbar was applied, and the mixture was heated to 100°C and held for 80 min to distill off the water.

[0173] The mixture was purged three times with N 2 . The vessel was then tested for pressure tightness, set to 0.5 bar gauge pressure (1.5 bar absolute), heated to 127°C, and then the pressure adjusted to 1.6 bar absolute. 59.7 g (1.358 mol) of EO were added at 127°C, p max was 3.9 bar absolute. The mixture was left for 30 minutes until constant pressure was reached, after which it was released to 1.0 bar absolute.

[0174] 625.5 g (8.688 mol) of BuO (butylene oxide) were added at 127°C, p max was 3.1 bar absolute. Intermittent depressurization was necessary due to the increase in the filling level. The BuO addition was stopped, the reaction was allowed to complete for 1 h until the pressure was constant, and then the depressurization was reduced to 1.0 bar absolute. The BuO addition was then continued. P max remained at 3.1 bar (first depressurization after 610 g of BuO, total BuO addition time 8 h including the depressurization pause). After the BuO addition, the reaction was allowed to continue for 8 h and then heated to 135°C. 83.6 g (1.901 mol) of EO were then added at 135°C, p max was 3.1 bar absolute. After the EO addition, the reaction was allowed to continue for 4 h. The mixture was cooled to 100°C, and residual oxide was removed until the pressure remained below 10 mbar for at least 10 minutes. Then, 0.5% water was added at 120°C, followed by removal until the pressure remained below 10 mbar for at least 10 minutes.The vacuum was released with N2, and 100 ppm of butylhydroxytoluene (BHT) was added. Filling was carried out at 80°C under N2.

[0175] A hydroxybutyl vinyl ether alkoxylate with 24.5 EO units, 16 BuO units, and 3.5 EO units (monomer M2) is obtained. Analysis (mass spectrum, GPC, 1< H NMR in CDCl 3 , 1< H NMR in MeOD) confirmed the structure. General preparation example for copolymers A and B

[0176] The following components were mixed in a 2 l three-necked flask equipped with a stirrer and thermometer: 290 g distilled water, 242.5 g acrylamido-2-methylpropanesulfonic acid, Na salt (50 wt.% solution in water; 24.7 mol%), 1.2 g silicone defoamer, 2.4 g pentasodium diethylenetriamine pentaacetate (complexing agent), 228.8 g acrylamide (50 wt.% solution in water; 75.2 mol%), 4.6 g monomers M1 (comparative example, copolymer B) or monomer M2 (according to the invention, copolymer A)

[0177] The solution was adjusted to pH 6 with 20% sodium hydroxide solution, inertized by purging with nitrogen for 10 minutes, and cooled to approximately 5°C. The solution was transferred to a plastic container, and then 200 ppm of 2,2'-azobis(2-amidinopropane) dihydrochloride (as a 1 wt% solution), 10 ppm of tert-butyl hydroperoxide (as a 0.1 wt% solution), 5 ppm of FeSO4*7H2O (as a 1 wt% solution), and 6 ppm of sodium bisulfite (as a 1 wt% solution) were added successively. Polymerization was initiated by irradiation with UV light (two Philips tubes; Cleo Performance 40 W). After approximately 2 hours, the hard gel was removed from the plastic container and cut into approximately 5 cm × 5 cm × 5 cm gel cubes using scissors. Before the gel cubes were ground using a conventional meat grinder, they were coated with a commercially available release agent. The release agent was a polydimethylsiloxane emulsion diluted 1:20 with water.The resulting gel granules were evenly distributed on drying grids and dried in a circulating air drying cabinet at approximately 90 to 120°C in vacuum until constant weight was reached. Preparation of copolymer C based on monomer M2 (comparative example)

[0178] 663.77 g of demineralized water were placed in a 2-liter polymerization reactor equipped with a stirrer, reflux condenser, thermometer, and inert gas connection. While stirring, 151.60 g (0.331 mol) of 2-acrylamido-2-methylpropanesulfonic acid, Na salt (50% solution in water), 1.0 g of Xiameter AFE-0400 (silicone defoamer), 142.68 g (1.00 mol) of acrylamide (50% solution in water), and 3.0 g of Trilon C (5% aqueous solution of the pentasodium salt of diethylenetriaminepentaacetic acid) were added. The pH was then adjusted to 6.0 with a 5% NaOH solution and / or 5% H 2 SO 4 solution. Subsequently, 2.85 g (0.0011 mol) of monomer M2 and 1.0 g of sodium hypophosphite (10% solution in water) were added as a regulator. After the addition of 22.01 g of demineralized water, the pH was readjusted to 6.0 with a 5% NaOH solution and / or 5% H 2 SO 4 solution. The solution was rendered inert by purging with nitrogen for 10 minutes and heated to 60°C.Subsequently, 1.6 g of tetraethylenepentamine (20 wt% solution in water) and 10.0 g of sodium peroxodisulfate (20 wt% solution in water) were added successively to initiate the polymerization. After the temperature peak, 5.0 g of 2,2'-azobis(2-methylpropionamidine) dihydrochloride (10% solution in water) were added, and the mixture was stirred for a further 1 hour at 65 °C to complete the polymerization. Application tests

[0179] The calcium sulfate flow screed consisted of 39.55 parts by weight of anhydrite and 60.0 parts by weight of standard sand (DIN EN 196-1). 0.45 parts by weight of potassium sulfate was added as a stimulant. The amount of water used was 14.0 parts by weight, corresponding to a water binder value of 0.35. A polycarboxylate ether was added to liquefy the calcium sulfate flow screed. The polycarboxylate ether content of 0.04 parts by weight was selected so that the calcium sulfate flow screed, without the addition of a copolymer, achieved a Hägermann cone slump of 280±5 mm 5 minutes after the water was added.

[0180] The calcium sulfate self-leveling screeds were produced in accordance with DIN EN 196-1:2005 in a mortar mixer with a capacity of approximately 5 liters. Water, superplasticizer, copolymer (see Table 1), and anhydrite were added to the mixing container. Immediately afterward, the mixing process began at a low agitator speed (140 revolutions per minute (rpm)). After 30 seconds, the standard sand was added evenly to the mix over a period of 30 seconds. The mixer was then switched to a higher speed (285 rpm), and mixing continued for another 30 seconds. The mixer was then stopped for 90 seconds. During the first 30 seconds, the calcium sulfate self-leveling screed, which had adhered to the wall and the bottom of the bowl, was removed with a rubber scraper and placed in the center of the bowl.After the break, the calcium sulfate self-leveling screed was mixed for another 60 seconds at the higher mixing speed. The total mixing time was 4 minutes.

[0181] To assess the influence of the copolymer on the flow properties of the calcium sulfate flow screed, the slump of all samples was determined immediately after the mixing process using a Hägermann cone without adding compaction energy, based on the SCC guideline of the German Committee for Reinforced Concrete (see: German Committee for Reinforced Concrete Construction (ed.): DAfStb - Guideline for Self-Compacting Concrete (SCC Guideline). Berlin, 2003). The Hägermann cone (top diameter = 70 mm, bottom diameter = 100 mm, h = 60 mm) was placed centrally on a dry glass plate with a diameter of 400 mm and filled to the specified height with calcium sulfate flow screed. Immediately after leveling or 5 minutes after the first contact between anhydrite and water, the Hägermann cone was removed, held for 30 seconds over the flowing calcium sulfate screed to allow it to drain, and then removed.Once the slump stopped, the diameter was measured using a caliper along two perpendicular axes, and the mean value was calculated. The slump is a parameter for the yield point of a calcium sulfate screed (see: Roussel, N. et al.: Cement and Concrete Research, Vol. 35, No. 5, (2005), pp. 817-822). As the slump decreases, the calcium sulfate screed becomes more difficult to work with.

[0182] To characterize the influence of the copolymer on the robustness of the calcium sulfate screed against sedimentation and bleeding (settlement of water on the surface), 200 ml of the calcium sulfate screed was mixed and poured into a 35 mm diameter glass cylinder (see: A. Perrot et al. / Cement and Concrete Research 42 (2012), pp. 937-944). After a rest period of 30, 60, and 120 minutes, the height of the water film (bleeding water) on the surface of the calcium sulfate screed was measured. The higher the water film on the surface of the mortar, the lower the stabilizing effect of the copolymer used. The results are summarized in Table 1. Table 1: Results of the application tests stabilizer Dosage [wt% based on anhydrite] Flow Height of the water film in [mm] after [cm] 0 min 30 minutes 60 minutes 120 minutes Molecular weight average M Reference without copolymer 0.000 28.4 0.000 0.042 0.161 0.289 Copolymer A based on monomer M2 (according to the invention) 0.030 24.1 0.000 0.000 0.035 0.127 7,2 · 10 6< 0.050 23.7 0.000 0.000 0.000 0.000 g / mol 0.100 21.8 0.000 0.000 0.000 0.000 Copolymer B based on monomer M1 (comparative example) 0.030 20.6 0.000 0.020 0.078 0.323 0.050 20.7 0.000 0.000 0.000 0.037 0.100 19.4 0.000 0.000 0.000 0.000 Copolymer C based on monomer M2 (comparative example) 0.030 27.5 0.000 0.056 0.128 0.428 0,34 · 10 6< 0.050 27.0 0.000 0.000 0.128 0.287 g / mol

[0183] The comparative example copolymer B is based on the disclosure of US 8,362,180 (example in column 27, line 40 to column 28, line 14 with monomer M2).

[0184] A dosage of 0.05 wt.% of copolymer A is sufficient to completely prevent sedimentation after 120 min, while at the same time a good flow rate can be achieved.

[0185] The average molecular weight M of the copolymer was determined, as previously described, using the Mark-Houwink relationship (1). The parameters K and α are unknown for the polymer-solvent pair in question. Therefore, the parameters for pure polyacrylamide in water were used (according to J. Klein, KD Conrad, Makromol. Chem. 1980, 18, 227), i.e., K = 0.0049 and α = 0.8.

[0186] For the determination of intrinsic viscosity [ nA 0.5% solution of the copolymer in water was prepared. This was diluted with a buffer (116.66 g NaCl + 32.26 g Na2HPO4*12H2O + 1.795 g Na2HPO4*H2O in 2 liters of demineralized water) to obtain a c = 0.01% polymer solution. This solution was analyzed using an Ubbelohde viscometer (at 20 °C; Ubbelohde capillary type 1). The intrinsic viscosity was determined via the flow time of the 0.01% polymer solution, using the solvent without polymer as a reference.

[0187] The flow time (t(polymer)) of the polymer solution was determined in comparison to the pure solvent (t LM ) as a reference (Δt = t(polymer)-t LM ). The intrinsic viscosity [ n ] can be calculated from this according to Solomon-Ciuta: η = 2 v relativ − 1 − 2 lnv relativ c mit v relativ = c × v reduziert + 1 und v reduziert = Δ t c × t LM

Claims

1. Composition comprising (a)α at least one inorganic binder (β) at least one water-soluble copolymer based on (a) 0.1 to 20 wt% of at least one monomer of the formula (I),         H2C=C(R1)-R2-O-(-CH2-CH2-O-)k-(-CH2-CH(R3)-O-)1-(-CH2-CH2-O-)m-R4     (I) where the units -(-CH2-CH2-O-)k, -(-CH2-CH(R3)-O-)l and - (-CH2-CH2-O-)m are arranged in a block structure in the order shown in formula (I) and the indices and radicals have the following meanings: k: is from 10 to 150; l: is from 5 to 25; m: is from 1 to 15; R1: is H or methyl; R2: is, each independently of one another, a single bond or a divalent, linking group selected from the group consisting of -(CnH2n)- and -O-(Cn'H2n')- and -C(O)-O-(Cn"H2n")-, where n, n' and n" are each a natural number from 1 to 6; R3: is a hydrocarbon radical having at least 2 carbon atoms or an ether group of the general formula -CH2-OR3', where R3' is a hydrocarbon radical having at least 2 carbon atoms and where R3 can be identical or different within the group -(-CH2-CH(R3)-O-)l; R4: is, each independently of one another, H or a hydrocarbon radical having 1 to 4 carbon atoms, and (b) 25 to 99.9 wt% of at least one monoethylenically unsaturated hydrophilic monomer (b) different from monomer (a), where the wt% figures are in each case based on the total amount of all monomers in the copolymer and the at least one copolymer has a molar mass average M of 1 500 000 to 30 000 000 g / mol, which is determined according to the Mark-Houwink relationship (1), M = η K 1 / α where K = 0.0049, α = 0.8 and [η] represents the intrinsic viscosity.

2. Composition according to Claim 1, characterized in that the inorganic binder is at least one from the series calcium sulfate n-hydrate, Portland cement, white cement, calcium aluminate cement, calcium sulfoaluminate cement, geopolymer, and latent hydraulic and / or pozzolanic binder.

3. Composition according to Claim 1 or 2, characterized in that the index k is from 23 to 26.

4. Composition according to any of Claims 1 to 3, characterized in that the index 1 is from 8.5 to 17.25.

5. Composition according to any of Claims 1 to 4, characterized in that the radicals and indices have the following meaning: k: is from 23 to 26; l: is from 12.75 to 17.25; m: is from 2 to 5; R1: is H; R2: is a divalent, linking group -O-(Cn'H2n')-, where n' is 4, R3: is a hydrocarbon radical having 2 carbon atoms; R4: is H.

6. Composition according to any of Claims 1 to 5, characterized in that at least one of the monomers (b) is a monomer comprising acid groups, the acid groups comprising at least one group selected from the group of -COOH, -SO3H and -PO3H2 and salts thereof.

7. Composition according to any of Claims 1 to 6, characterized in that it comprises at least two different monoethylenically unsaturated hydrophilic monomers (b), namely at least one neutral hydrophilic monomer (b1), and at least one hydrophilic anionic monomer (b2) which comprises at least one acid group selected from the group of -COOH,-SO3H and -PO3H2 and salts thereof.

8. Composition according to any of Claims 1 to 7, characterized that the at least one copolymer is a copolymer based on at least one monomer (a) of the formula (I), and also acrylamide as neutral hydrophilic monomer (b1), and acrylamido-2-methylpropanesulfonic acid (AMPS) as anionic hydrophilic monomer (b2).

9. Composition according to any of Claims 1 to 8, characterized in that the component (β) additionally comprises (c) at least one nonionic, nonpolymerizable, surface active component.

10. Composition according to any of Claims 1 to 9, characterized in that it comprises, based on its dry mass, at least 20 wt% of the at least one inorganic binder and 0.0005 to 5 wt% of the at least one copolymer.

11. Process for producing a composition according to any of Claims 1 to 10, characterized in that the monomer (a) of the general formula (I) is prepared by a process comprising the following steps: a) reaction of a monoethylenically unsaturated alcohol Al of the general formula (II)         H2C=C(R1)-R2-OH     (II), with ethylene oxide, where the radicals R1 and R2 are as defined above; with addition of an alkaline catalyst K1 containing KOMe and / or NaOMe, giving an alkoxylated alcohol A2; b) reaction of the alkoxylated alcohol A2 with at least one alkylene oxide Z of the formula (Z) where R3 is as defined above; with addition of an alkaline catalyst K2; where the concentration of potassium ions in the reaction in step b) is less than or equal to 0.9 mol%, based on the alcohol A2 used; and where the reaction in step b) is carried out at a temperature of less than or equal to 135°C, giving an alkoxylated alcohol A3 of the formula (III),         H2C=C(R1)-R2-O-(-CH2-CH2-O-)K-(-CH2-CH(R3)-O-)l-H     (III) where the radicals and indices R1, R2, R3, k and l are as defined above; c) reaction of the alcohol A3 with ethylene oxide, giving an alkoxylated alcohol A4 corresponding to the monomer (a) of the formula (I) with R4 = H and m = 1 to 15; d) optional etherification of the alkoxylated alcohol A4 with a compound         R4-X where R4 is a hydrocarbon radical having 1 to 4 carbon atoms and X is a leaving group, preferably selected from the group of Cl, Br, I, -O-SO2-CH3 (mesylate), -O-SO2-CF3 (triflate) and -O-SO2-OR4, giving a monomer (a) of the formula (I) where R4 = hydrocarbon radical having 1 to 4 carbon atoms, radical polymerization of the resulting monomer (a) with a monomer (b), giving the water-soluble copolymer (β), and contacting of the water-soluble copolymer (β) with the at least one inorganic binder.

12. Process for producing a composition according to any of Claims 1 to 10, characterized in that the copolymer is prepared by subjecting at least one monomer (a) and at least one hydrophilic monomer (b) to an aqueous solution polymerization and contacting the resulting water-soluble copolymer (β) with the at least one inorganic binder.

13. Process according to Claim 12, characterized in that the solution polymerization is carried out at a pH in the range from 5.0 to 9.

14. Process according to Claim 12 or 13, characterized in that the solution polymerization is carried out in the presence of at least one surface-active component (c).

15. Use of the copolymer of component (β) as rheological additive in a composition according to any of Claims 1 to 10.