Spray drying aid for redispersible dispersion powder

Abstract

The present invention relates to a specific pyrrolidone-containing polymer (PP) and its use as a spray drying additive for aqueous polymer dispersions (also referred to as a spray drying aid; sDA) is disclosed. The invention further relates to a method of manufacturing a redispersible dispersion powder (RDP) comprising said SDA, as well as to an RDP comprising said SDA and certain uses thereof. In addition, the invention relates to a method for producing the specific pyrrolidone-containing polymer (PP).

Description

[0001] The present invention relates to the use of a specific pyrrolidone-containing polymer (PP) as a spray drying additive (also known as spray drying aid; SDA) for aqueous polymer dispersions. The present invention further relates to a method for the manufacture of a redispersible dispersion powder (RDP) comprising said SDA, as well as an RDP comprising said SDA and certain uses thereof. In addition, the present invention relates to a specific pyrrolidone-containing polymer (PP) and a method for producing the specific pyrrolidone-containing polymer (PP).

[0002] A suitable method for converting an aqueous dispersion into a redispersible dispersion powder (RDP) is spray drying. This involves spraying and dehydrating the aqueous dispersion in a stream of hot air. In order to ensure spray drying of the dispersion and redispersibility of the dispersion powder, a spray drying additive (SDA) is usually added to the aqueous dispersion. During the spray drying process, it is assumed that the SDA forms a protective shell around the dispersion particles, thereby preventing the particles from filming during the spray drying process.

[0003] Formaldehyde condensation products can be used as SDAs, such as melamine-formaldehyde (DE 2049114 A1), phenolsulfonic acid-formaldehyde (WO 98 / 03576 A1) and naphthalenesulfonic acid-formaldehyde condensation products (WO 98 / 03577 A1). However, these SDAs described in the prior art have disadvantages. For example, they discolor the dispersion powders, they show a coloring effect under UV light (yellow-brown discoloration), and formaldehyde is emitted during production and / or in the application system.

[0004] Therefore, there is a continuing need to provide suitable spray drying aids for aqueous polymer dispersions, methods of making redispersible dispersion powders comprising such suitable spray drying aids, and redispersible dispersion powders comprising such SDAs.

[0005] Against this background, it is an object of the present invention to provide a suitable spray drying aid for aqueous polymer dispersions. In this context, it is an object of the present invention to provide an SDA with less discoloration. In addition, it is an object of the present invention to provide an SDA with reduced formaldehyde emissions during manufacturing and / or in an application system (e.g. in a powder coating or construction material composition). In addition, it is an object of the present invention to provide an environmentally friendly SDA. In addition, it is an object of the present invention to provide a biodegradable pyrrolidone-containing polymer and to provide a method for preparing the biodegradable pyrrolidone-containing polymer. Another object of the present invention is to provide a redispersible dispersion powder with suitable redispersibility. An additional object of the present invention is to provide a stable powder coating and / or construction material composition. In this context, it is an object of the present invention to provide a powder coating and / or construction material composition with reduced discoloration and / or reduced formaldehyde emissions. In addition, it is an object of the present invention to provide a durable coating and / or construction material composition.

[0006] It has surprisingly been found that at least one of these objects can be achieved by using a pyrrolidone-containing polymer (PP) as claimed and disclosed herein as SDA. It has further been found that the powder coating and / or construction material composition as defined herein provides improved wet scrub resistance as well as suitable redispersibility. The inventors have further identified suitable biodegradable pyrrolidone-containing polymers that can be easily manufactured.

[0007] In a first aspect, the present invention relates to a pyrrolidone-containing polymer (PP) comprising at least one (monomer) unit of the general formula (I) to (III)

[0008]

[0009] wherein R is independently hydrogen, C1-C4-alkyl, or two groups R are linked to each other to form a six-membered ring;

[0010] X is -O- or -NR;

[0011] A is independently selected from C1-C 20 -alkanediyl, C3-C 20 -cycloalkanediyl and C6-C 20 - a group consisting of an arylene group,

[0012] Among them, C1-C 20 -alkanediyl is optionally interrupted by one or more non-adjacent oxygen atoms, sulfur atoms or functional groups -NR-, -CO-, -CO-O-, -CO-NR-, -SO- or -SO2-, in which the nitrogen atom is optionally protonated or quaternized,

[0013] Among them, C1-C 20 -alkanediyl and the C3-C 20 -cycloalkanediyl optionally carries at least one selected from C(=O)R 2 and SO3H, where

[0014] R 2 Selected from Cl, Br and OR 3 The group consisting of

[0015] R 3 Choose from H, C1-C 10 -alkyl, C3-C 10 -cycloalkyl and C2-C 15 -alkenyl group,

[0016] Among them, C6-C 20 -arylene is optionally inserted with oxygen, sulfur, -NR-, -SO- or -SO2- and is optionally substituted with -COOH or -SO3H or a mixture of these groups;

[0017] Z is a group of formula (IV)

[0018]

[0019] Where B is C1-C 20 -alkanediyl, C6-C 20 -cycloalkanediyl or a mixture of such groups, the C1-C 20 -alkanediyl optionally interrupted by one or more non-adjacent oxygen atoms, sulfur atoms or functional groups -NR-, -CO-, -CO-O-, -CO-NR-, -SO- or -SO2-, and optionally carrying an additional functional group -COOH or -SO3H, in which the nitrogen atom of the functional group -NR- is optionally protonated or quaternized

[0020] Or Z is a mixture of a group of formula (IV) and a group A;

[0021] Use as spray-drying aid for aqueous polymer dispersions. The first aspect also covers the use of the pyrrolidone-containing polymer (PP) as a spray-drying aid for aqueous polymer dispersions.

[0022] In the following, preferred embodiments of the pyrrolidone containing polymer (PP) and preferred embodiments of the aqueous polymer dispersion are described in further detail. It should be understood that each preferred embodiment is encompassed both individually and in combination with any other preferred embodiment of the preferred embodiments.

[0023] In a preferred embodiment A1 of the first aspect, the pyrrolidone-containing polymer (PP) comprises at least one unit of the general formula (I) to (II)

[0024]

[0025] wherein R is independently hydrogen or C1-C2-alkyl;

[0026] X is -NR;

[0027] A is independently selected from C1-C 20 -alkanediyl group, the C1-C 20 -alkanediyl optionally carries at least one selected from C(=O)R 2 and SO3H, where

[0028] R 2 Selected from Cl, Br and OR 3 The group consisting of

[0029] R 3 Choose from H, C1-C 10 -alkyl, C3-C 10 -cycloalkyl and C2-C 15 A group consisting of alkenyl groups;

[0030] Z is a group of formula (IV)

[0031]

[0032] Where B is C1-C 20 -alkylene, the C1-C 20 The -alkylene radical optionally carries an additional functional group -COOH or -SO3H, or Z is a mixture of a radical of the formula (IV) and a radical A.

[0033] In preferred embodiment A2 of the first aspect, the aqueous polymer dispersion comprises a (co)polymer selected from the group consisting of acrylate polymers, acrylic acid-styrene copolymers, styrene-butadiene-based copolymers, vinyl acetate polymers and ethylene-vinyl acetate copolymers, preferably a (co)polymer selected from the group consisting of acrylic acid-styrene copolymers, styrene-butadiene-based copolymers and ethylene-vinyl acetate copolymers, more preferably an acrylic acid-styrene copolymer.

[0034] In a second aspect, the present invention relates to a method for producing a redispersible dispersion powder (RDP), the method comprising the steps of:

[0035] i) a pyrrolidone-containing polymer (PP) comprising at least one unit of the general formula (I) to (III)

[0036]

[0037] wherein R is independently hydrogen, C1-C4-alkyl, or two groups R are linked to each other to form a six-membered ring;

[0038] X is -O- or -NR;

[0039] A is independently selected from C1-C 20 -alkanediyl, C3-C 20 -cycloalkanediyl and C6-C 20 - a group consisting of an arylene group,

[0040] Among them, C1-C 20 -alkanediyl is optionally interrupted by one or more non-adjacent oxygen atoms, sulfur atoms or functional groups -NR-, -CO-, -CO-O-, -CO-NR-, -SO- or -SO2-, in which the nitrogen atom is optionally protonated or quaternized,

[0041] Among them, C1-C 20 -alkanediyl and the C3-C 20 -cycloalkanediyl optionally carries at least one selected from C(=O)R 2 and SO3H, where

[0042] R 2 Selected from Cl, Br and OR 3 The group consisting of

[0043] R 3 Choose from H, C1-C 10 Alkyl, C3-C 10 Cycloalkyl and C2-C 15 The group consisting of alkenyl groups,

[0044] Among them, C6-C 20 -arylene is optionally inserted with oxygen, sulfur, -NR-, -SO- or -SO2- and is optionally substituted with -COOH or -SO3H or a mixture of these groups;

[0045] Z is a group of formula (IV)

[0046]

[0047] Where B is C1-C 20 -alkanediyl, C6-C 20 -cycloalkanediyl or a mixture of such groups, the C1-C 20-alkanediyl optionally interrupted by one or more non-adjacent oxygen atoms, sulfur atoms or functional groups -NR-, -CO-, -CO-O-, -CO-NR-, -SO- or -SO2-, and optionally carrying an additional functional group -COOH or -SO3H, in which the nitrogen atom of the functional group -NR- is optionally protonated or quaternized

[0048] or Z is a mixture of a group of formula (IV) and a group A,

[0049] mixing with an aqueous polymer dispersion, the aqueous polymer dispersion preferably comprising a (co)polymer selected from the group consisting of acrylate polymers, acrylic acid-styrene copolymers, styrene-butadiene based copolymers, vinyl acetate polymers and ethylene-vinyl acetate copolymers;

[0050] ii) spray drying the mixture obtained in step i).

[0051] In a preferred embodiment B1 of the second aspect, in step i), the pyrrolidone-containing polymer (PP) is mixed with the aqueous polymer dispersion in an amount of 4 to 20% by weight, preferably 5 to 15% by weight, in particular 6 to 12% by weight, based on the solids content of the aqueous polymer dispersion.

[0052] In a third aspect, the present invention relates to a redispersible dispersion powder (RDP) obtainable by the process according to the second aspect.

[0053] In a fourth aspect, the present invention relates to a redispersible dispersion powder (RDP), comprising a (co)polymer and a pyrrolidone-containing polymer (PP), the (co)polymer being selected from the group consisting of acrylate polymers, acrylic acid-styrene copolymers, styrene-butadiene-based copolymers, vinyl acetate polymers and ethylene-vinyl acetate copolymers, and the pyrrolidone-containing polymer (PP) comprising at least one unit of the general formula (I) to (III)

[0054]

[0055] wherein R is independently hydrogen, C1-C4-alkyl, or two groups R are linked to each other to form a six-membered ring;

[0056] X is -O- or -NR;

[0057] A is independently selected from C1-C 20 -alkanediyl, C3-C 20 -cycloalkanediyl and C6-C 20 - a group consisting of an arylene group,

[0058] Among them, C1-C20 -alkanediyl is optionally interrupted by one or more non-adjacent oxygen atoms, sulfur atoms or functional groups -NR-, -CO-, -CO-O-, -CO-NR-, -SO- or -SO2-, in which the nitrogen atom is optionally protonated or quaternized,

[0059] Among them, C1-C 20 -alkanediyl and the C3-C 20 -cycloalkanediyl optionally carries at least one selected from C(=O)R 2 and SO3H, where

[0060] R 2 Selected from Cl, Br and OR 3 The group consisting of

[0061] R 3 Choose from H, C1-C 10 Alkyl, C3-C 10 Cycloalkyl and C2-C 15 The group consisting of alkenyl groups,

[0062] Among them, C6-C 20 -arylene is optionally inserted with oxygen, sulfur, -NR-, -SO- or -SO2- and is optionally substituted with -COOH or -SO3H or a mixture of these groups;

[0063] Z is a group of formula (IV)

[0064]

[0065] Where B is C1-C 20 -alkanediyl, C6-C 20 -cycloalkanediyl or a mixture of such groups, the C1-C 20 -alkanediyl optionally interrupted by one or more non-adjacent oxygen atoms, sulfur atoms or functional groups -NR-, -CO-, -CO-O-, -CO-NR-, -SO- or -SO2-, and optionally carrying an additional functional group -COOH or -SO3H, in which the nitrogen atom of the functional group -NR- is optionally protonated or quaternized

[0066] Alternatively, Z is a mixture of a group of formula (IV) and a group A.

[0067] In a fifth aspect, the present invention relates to a method of making a powder paint or coating, the method comprising blending a redispersible dispersion powder (RDP) according to the third or fourth aspect with a pigment.

[0068] In a sixth aspect, the present invention relates to a method of making a construction material composition, the method comprising blending a redispersible dispersion powder (RDP) according to the third or fourth aspect with cement.

[0069] In a seventh aspect, the present invention relates to a pyrrolidone-containing polymer (PP) obtainable by polymerization of a reaction mixture (rM2), wherein the reaction mixture (rM2) comprises at least the following components:

[0070] (A) at least one itaconic acid derivative, and

[0071] (B) at least one amino acid of the general formula (1)

[0072] H2N-R 1 -C(=O)-R 2 (1)

[0073] in

[0074] R 1 Selected from at least monosubstituted C2-C 20 -alkanediyl and at least monosubstituted C3-C 20 -Cycloalkane

[0075] The group consisting of two radicals, wherein the substituent is NH2;

[0076] R 2 Selected from Cl, Br and OR 3 The group consisting of

[0077] R 3 Choose from H, C1-C 10 -alkyl, C3-C 10 -cycloalkyl and C2-C 15 -alkenyl group.

[0078] In a preferred embodiment G1 of the seventh aspect, component (A) is selected from the group consisting of itaconic acid, itaconic anhydride, itaconic esters and itaconic acid halides.

[0079] In a preferred embodiment G2 of the seventh aspect, component (B) is selected from the group consisting of L-lysine, D-lysine and a racemic mixture of L-lysine and D-lysine.

[0080] In an eighth aspect, the present invention relates to a method for producing a pyrrolidone-containing polymer (PP), wherein the method comprises the polymerization of a reaction mixture (rM2), wherein the reaction mixture (rM2) comprises at least the following components:

[0081] (A) at least one itaconic acid derivative, and

[0082] (B) at least one amino acid of the general formula (1)

[0083] H2N-R 1 -C(=O)-R 2 (1)

[0084] in

[0085] R 1 Selected from at least monosubstituted C2-C 20 Alkanediyl and at least monosubstituted C3-C 20 The group consisting of cycloalkanediyl, wherein the substituent is NH2;

[0086] R 2 Selected from Cl, Br and OR 3 The group consisting of

[0087] R 3 Choose from H, C1-C 10 Alkyl, C3-C 10 Cycloalkyl and C2-C 15 A group consisting of alkenyl.

[0088] Figure 1 The biodegradability of spray drying aid 4 (SDA4) is depicted. DETAILED DESCRIPTION

[0089] Before describing exemplary embodiments of the present invention in detail, definitions important for understanding the present invention are given.

[0090] As used in this specification and the appended claims, the singular form "one / kind" also includes the respective plural forms, unless the context clearly indicates otherwise. In the context of the present invention, the terms "about" and "approximately" represent the precision range that those skilled in the art will understand to still ensure the technical effect of the discussed feature. The term usually indicates that the deviation from the indicated numerical value is ±10%, preferably ±5%, more preferably ±2%, and especially ±1%. It should be understood that the term "comprising" is not restrictive. For the purposes of the present invention, the term "consisting of..." is considered to be a preferred embodiment of the term "comprising". If a group is defined as comprising at least a certain number of embodiments hereinafter, this means that a group preferably consisting only of these embodiments is also covered. In addition, the terms "first", "second", "third" or "(a)", "(b)", "(c)", "(d)" and the like in the specification and claims are used to distinguish between similar elements, and are not necessarily used to describe sequential or chronological order. It should be understood that the terms used in this way are interchangeable where appropriate, and the embodiments of the present invention described herein can be operated in other sequences different from those described or shown herein. Where the terms "first", "second", "third" or "(a)", "(b)", "(c)", "(d)", "i", "ii", etc. refer to steps of a method or use or an assay, there is no continuity of time or time interval between the steps, i.e., the steps may be performed simultaneously, or there may be time intervals of seconds, minutes, hours, days, weeks, months or even years between the steps, unless otherwise stated in the application presented above or below. It should be understood that the present invention is not limited to the specific methods, protocols, reagents, etc. described herein, as these may vary. It should also be understood that the terminology used herein is for the purpose of describing specific embodiments only and is not intended to limit the scope of the present invention, which is limited only by the appended claims. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the art.

[0091] As used herein, the term "substituted" means that a hydrogen atom bonded to a designated atom is replaced with a designated substituent, provided that the substitution results in a stable or chemically feasible compound. Unless otherwise specified, the substituted atom may have one or more substituents and each substituent is independently selected.

[0092] When the term "unsubstituted" or "substituted" is not explicitly mentioned in reference to a moiety, the moiety is deemed to be unsubstituted.

[0093] As used herein, the term "alkyl" denotes in each case a straight-chain or branched alkyl group generally having 1 to 10 carbon atoms, preferably 1 to 5 or 1 to 4 carbon atoms or 1 to 3 or 1 or 2 carbon atoms. Examples of the alkyl group are methyl, ethyl, n-propyl, isopropyl, n-butyl, 2-butyl, isobutyl, tert-butyl, n-pentyl, 1-methylbutyl, 2-methylbutyl, 3-methylbutyl, 2,2-dimethylpropyl, 1-ethylpropyl, n-hexyl, 1,1-dimethylpropyl, 1,2-dimethylpropyl, 1-methylpentyl, 2-methylpentyl, 3-methylpentyl, 4-methylpentyl, 1,1-dimethylbutyl, 1,2-dimethylbutyl, 1,3-dimethylbutyl, 2,2-dimethylbutyl, 2,3-dimethylbutyl, 3,3-dimethylbutyl, 1-ethylbutyl, 2-ethylbutyl, 1,1,2-trimethylpropyl, 1,2,2-trimethylpropyl, 1-ethyl-1-methyl-propyl and 1-ethyl-2-methylpropyl.

[0094] As used herein, the term "alkanediyl" represents a hydrocarbon having, for example, 2 to 20 carbon atoms and two free valences in each case. It is therefore a diradical having, for example, 2 to 20 carbon atoms. The term "alkanediyl" encompasses straight and branched chains having, for example, 2 to 20 carbon atoms and two free valences, as well as saturated and unsaturated hydrocarbons. Saturated hydrocarbons are preferred. Examples of C2-C20-alkanediyl are ethylene (second-1,2-diyl, dimethylene), third-1,3-diyl (trimethylene), propylene (third-1,2-diyl) and fourth-1,4-diyl (tetramethylene). Alkanediyl bridges a certain group to the rest of the molecule.

[0095] The term "cycloalkanediyl" as used herein represents in each case a cyclic hydrocarbon having, for example, 3 to 20 carbon atoms and two free valences. It is therefore a diradical having, for example, 3 to 20 carbon atoms. The term "cycloalkanediyl" encompasses cyclic hydrocarbons and hydrocarbons having a cyclic fraction and a straight-chain fraction having, for example, 3 to 20 carbon atoms and two free valences. Examples of C3-C20-cycloalkanediyl are cyclopropanediyl, cyclobutanediyl, cyclopentanediyl, cyclohexanediyl, cycloheptanediyl, cyclooctanediyl and cyclodecanediyl.

[0096] The term "arylene" as used herein represents in each case a linking aromatic cyclic moiety which generally has 6 to 20 carbon atoms, for example 6, 7, 8, 10 or 12 carbon atoms. An arylene bridges a group to the rest of the molecule. An arylene may, for example, be a phenylene. In this connection, it is to be understood that aromatic means that the Hückel (4n+2) rule is satisfied.

[0097] The term "cycloalkyl" as used herein represents in each case a cyclic hydrocarbon radical having, for example, 3 to 10 carbon atoms. The term "cycloalkyl" also encompasses hydrocarbons having a cyclic fraction and a linear fraction having, for example, 3 to 10 carbon atoms and one free valency. Examples of such cycloalkyl radicals include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl and cyclodecyl.

[0098] The term "alkenyl" as used herein represents in each case an unsaturated hydrocarbon radical having usually 2 to 15, preferably 2 to 10 carbon atoms, containing at least one carbon-carbon double bond in any position, for example vinyl (vinyl), allyl (2-propene-1-yl), 1-propene-1-yl, 2-propene-2-yl, methallyl (2-methylprop-2-ene-1-yl), 2-butene-1-yl, 3-butene-1-yl, 2-pentene-1-yl, 3-pentene-1-yl, 4-pentene-1-yl, 1-methylbut-2-ene-1-yl, 2-ethylprop-2-ene-1-yl, pentenyl, hexenyl, etc. If geometric isomers about the double bond are possible, the present invention relates to both E-isomers and Z-isomers. Preferred alkenyls according to the invention are terminal alkenyls. The bonding of vinyl is exemplified as follows:

[0099]

[0100] The organic moieties mentioned in the above definitions of the variables are collective names for the individual lists of the individual group members. n -C m The possible number of carbon atoms in the group is indicated in each case.

[0101] As used in the context of the present invention, "at least one itaconic acid derivative" covers embodiments in which exactly one itaconic acid derivative is used, as well as embodiments in which a mixture of two or more itaconic acid derivatives is used. The same applies to the use of "at least" in terms such as "at least one diamine", "at least one amino acid", "at least one (inorganic / organic) pigment", "at least one redispersible dispersion powder", "at least one (co)polymer", "at least one filler", "at least one dispersant", "at least one thickener", "at least one defoamer" and the like.

[0102] The terms "component (A)" and "at least one itaconic acid derivative" are used synonymously in the context of the present invention and thus have the same meaning.

[0103] The same applies to the terms "component (B)" and "at least one amino acid". These terms are also used synonymously in the context of the present invention and therefore have the same meaning.

[0104] When referring to weight percentages of compositions and ingredients contained therein, it is to be understood that the total amount of ingredients according to the present invention does not exceed 100% (± 1% due to rounding).

[0105] As used herein, the term "particle" or "polymer particle" refers to a polymer fragment having a specific particle size Dx for a specific particle size distribution, wherein x% of the particles have a diameter less than the Dx value. 50 The particle size is the median of the particle size distribution. The particle size distribution can be determined, for example, via dynamic light scattering (e.g. according to ISO 22412:2008). The particle size distribution can be expressed as a volume distribution, a surface distribution or a number distribution. Preferably, the Dx value is a number distribution in which x% of the total number of particles have a smaller diameter.

[0106] Preferred embodiments are described below with respect to the use of SDA, methods of making redispersible dispersion powders (RDPs), RDPs and methods of making powder coatings or coatings, build material compositions, specific pyrrolidone-containing polymers (PPs) and methods of making the specific pyrrolidone-containing polymers (PPs). It should be understood that the preferred embodiments of the present invention are encompassed by the scope of the present invention both individually and in all possible combinations with each other.

[0107] As indicated above, in one embodiment, the present invention relates to a pyrrolidone-containing polymer (PP) comprising at least one unit of the general formula (I) to (III)

[0108]

[0109]

[0110] wherein R is independently hydrogen, C1-C4-alkyl, or two groups R are linked to each other to form a six-membered ring;

[0111] X is -O- or -NR;

[0112] A is independently selected from C1-C 20 -alkanediyl, C3-C 20 -cycloalkanediyl and C6-C 20 - a group consisting of an arylene group,

[0113] Among them, C1-C 20 -alkanediyl is optionally interrupted by one or more non-adjacent oxygen atoms, sulfur atoms or functional groups -NR-, -CO-, -CO-O-, -CO-NR-, -SO- or -SO2-, in which the nitrogen atom is optionally protonated or quaternized,

[0114] Among them, C1-C 20-alkanediyl and the C3-C 20 -cycloalkanediyl optionally carries at least one selected from C(=O)R 2 and SO3H, where

[0115] R 2 Selected from Cl, Br and OR 3 The group consisting of

[0116] R 3 Choose from H, C1-C 10 -alkyl, C3-C 10 -cycloalkyl and C2-C 15 -alkenyl group,

[0117] Among them, C6-C 20 -arylene is optionally inserted with oxygen, sulfur, -NR-, -SO- or -SO2- and is optionally substituted with -COOH or -SO3H or a mixture of these groups;

[0118] Z is a group of formula (IV)

[0119]

[0120] Where B is C1-C 20 -alkanediyl, C6-C 20 -cycloalkanediyl or a mixture of such groups, the C1-C 20 -alkanediyl optionally interrupted by one or more non-adjacent oxygen atoms, sulfur atoms or functional groups -NR-, -CO-, -CO-O-, -CO-NR-, -SO- or -SO2-, and optionally carrying an additional functional group -COOH or -SO3H, in which the nitrogen atom of the functional group -NR- is optionally protonated or quaternized

[0121] Or Z is a mixture of a group of formula (IV) and a group A;

[0122] Use as spray-drying aid for aqueous polymer dispersions. In this respect, the present invention also relates to the use of the pyrrolidone-containing polymer (PP) as a spray-drying aid for aqueous polymer dispersions.

[0123] In the following, preferred embodiments of polymers and uses thereof relevant to all aspects of the invention are described in more detail. It should be understood that each preferred embodiment is intended to be covered both individually and in combination with any one or more of the other preferred embodiments.

[0124] In the context of the present invention, "pyrrolidone-containing polymer (PP)" means that the polymer contains pyrrolidone groups, preferably pyrrolidone groups as part of the polymer backbone (in contrast to pyrrolidone groups that are only side groups). The polymer may be a pyrrolidone-containing copolymer. In various embodiments, the term as used herein therefore excludes polymers in which pyrrolidone groups are side groups, such as PVP. In various embodiments, the polymer of the present invention is therefore not PVP. Pyrrolidone groups as part of the backbone may mean that they are divalent repeating units of the polymer backbone structure. In general, pyrrolidone groups are known to those skilled in the art. Pyrrolidone groups are groups derived from pyrrolidone, formed by removing at least one hydrogen atom from any one of the ring atoms to generate free radicals. Divalent groups are explicitly covered by the term.

[0125] The pyrrolidone-containing polymers (PP) of the present invention are superior to known PVP polymers because they are more biodegradable and can be produced from renewable raw materials such as itaconic acid and amino acids, especially lysine. In addition, they are readily soluble in water and aqueous solutions with high polymer concentrations are readily available. Another advantage is that the polymers of the present invention can be synthesized as a melt or solid and do not have to be reacted in solution. It has further been found that the claimed pyrrolidone-containing polymers (PP) are less viscous, less hygroscopic and more stable on storage than conventional PVP polymers.

[0126] As used herein, "spray drying aids" refer to compounds that protect another compound or composition of spray drying from adverse effects that may occur when drying and being exposed to high temperatures and high pressures typical for commercial spray drying processes. Such adverse effects include, but are not limited to, irreversible aggregation and / or film formation of spray-dried compounds or compositions, which may damage their subsequent uses and / or applications, such as redispersion in liquid media. Spray drying aids achieve this by forming a protective shell or matrix that coats or embeds the spray-dried compound / composition during the spray drying process. Therefore, spray drying aids are functionally different from compounds used to dissolve or serve as protective colloids, because the latter are used to improve solubility or dispersibility in liquids (usually aqueous media), while the former need to withstand conditions during spray drying and be able to protect other compounds from the adverse effects of spray drying, such as by forming a protective shell around them or forming a protective matrix in which they are embedded. It is important to note that spray drying aids therefore work in a different manner from solubilizers or protective colloids, which are generally not suitable for preventing the formation of irreversible, insoluble and / or non-dispersible aggregates when drying. In order to avoid incorporation of polymers used as spray-drying aids into the polymer of the aqueous polymer dispersion to be spray-dried, which could impair their functionality, they are generally not present during the formation of the polymer to be spray-dried, but are added to the product polymer or to a composition containing the product polymer (such as the aqueous polymer dispersion referred to herein).

[0127] In a preferred embodiment, the pyrrolidone-containing polymer (PP) comprises at least one unit of the general formula (I) to (II)

[0128]

[0129] wherein R is independently hydrogen or C1-C2-alkyl;

[0130] X is -NR;

[0131] A is independently selected from C1-C 20 -alkanediyl group, the C1-C 20 -alkanediyl optionally carries at least one selected from C(=O)R 2 and SO3H, where

[0132] R 2 Selected from Cl, Br and OR 3 The group consisting of

[0133] R 3 Choose from H, C1-C 10 -alkyl, C3-C 10 -cycloalkyl and C2-C15 A group consisting of alkenyl groups;

[0134] Z is a group of formula (IV)

[0135]

[0136] Where B is C1-C 20 -alkylene, the C1-C 20 The -alkylene radical optionally carries an additional functional group -COOH or -SO3H, or Z is a mixture of a radical of the formula (IV) and a radical A.

[0137] Preferably, A is C1-C 20 -alkanediyl, more preferably C1-C 15 -alkanediyl, and especially C 1-10 -alkanediyl. In some embodiments, A is C1-alkanediyl, C2-alkanediyl, C3-alkanediyl, C4-alkanediyl, C5-alkanediyl or C6-alkanediyl, preferably C5-alkanediyl. The alkanediyl may preferably be linear and saturated. In various embodiments, it preferably carries a functional C(=O)R 2 group, optionally on a terminal carbon atom, such as a C1 carbon atom. In such embodiments, R 2 The group is preferably OR 3 , R 3 Preferably H.

[0138] Preferably, B is C1-C 15 -alkanediyl, more preferably C1-C 10 -alkanediyl, and especially C 1-8 -alkanediyl. In some embodiments, B is C1-alkanediyl, C2-alkanediyl, C3-alkanediyl, C4-alkanediyl, C5-alkanediyl or C6-alkanediyl, preferably C5-alkanediyl. The alkanediyl may preferably be straight chain and saturated. In various embodiments, it preferably carries a functional group -COOH, optionally on a terminal carbon atom, such as a C1 carbon atom.

[0139] In a preferred embodiment, the pyrrolidone-containing polymer (PP) is obtainable by polymerization of a reaction mixture (rM1), wherein the reaction mixture (rM1) comprises at least the following components:

[0140] (A) at least one itaconic acid derivative, preferably wherein component (A) is selected from the group consisting of itaconic acid, itaconic anhydride, itaconic esters and itaconic acid halides, and

[0141] (B) at least one diamine, preferably wherein the diamine is selected from the group consisting of ethylenediamine, 1,3-diaminopropane, 1,4-diaminobutane, 1,5-pentanediamine, 1,6-diaminohexane, 1,7-diaminoheptane, 1,8-diaminooctane and 1,9-diaminononane, more preferably selected from ethylenediamine and 1,5-pentanediamine.

[0142] In a preferred embodiment, the reaction mixture (rM1) comprises at least two diamines, preferably selected from the group consisting of ethylenediamine, 1,3-diaminopropane, 1,4-diaminobutane, 1,5-pentanediamine, 1,6-diaminohexane and 1,7-diaminoheptane, and in particular wherein the reaction mixture (rM1) comprises ethylenediamine and 1,5-pentanediamine.

[0143] Preferably, the reaction mixture (rM1) comprises component (A) and at least one diamine, preferably the sum of at least two diamines, in a molar ratio of 10:1 to 1:10, preferably 5:1 to 1:5, in particular 4:1 to 1:2 or 3:1 to 1:5.

[0144] In a preferred embodiment, the at least one itaconic acid derivative and the at least one diamine, preferably the sum of the at least two diamines, are present in the reaction mixture (rM1) in a molar ratio of 3:1 to 1:3, preferably 2:1 to 1:2, in particular 1.5:1 to 1:1.5.

[0145] In a preferred embodiment, the reaction mixture (rM1) comprises component (A) in a range of 35% to 99% by weight, preferably 40% to 90% by weight, more preferably 50% to 75% by weight, based on the sum of the weight percentages of component (A) and the at least one diamine, preferably based on the total weight of the reaction mixture (rM1), and the at least one diamine in a range of 1% to 65% by weight, preferably 10% to 60% by weight, more preferably 25% to 50% by weight.

[0146] Unless otherwise stated, all weight percentages of component (A) and of the at least one amine and optionally contained solvent (S) such as water are based on the composition of the reaction mixture (rM1) before the start of polymerization of the reaction mixture (rM1).

[0147] In this connection, the pyrrolidone-containing polymer (PP) preferably has a weight-average molecular weight (Mw; determined by gel permeation chromatography (GPC) with a 0.05 M aqueous ammonium formate / methanol mixture = 80:20 (volume parts) as eluent) of 500 to 100,000 g / mol, more preferably 1,000 to 10,000 g / mol, still more preferably 2,000 to 8,000 g / mol and in particular 3,000 to 6,000 g / mol. Preferably, the pyrrolidone-containing polymer (PP) has a number average molecular weight (Mn; determined by gel permeation chromatography (GPC) with a 0.05 M aqueous ammonium formate / methanol mixture = 80:20 (volume parts) as eluent) of 500 g / mol to 20,000 g / mol, more preferably 800 g / mol to 10,000 g / mol, still more preferably 1,000 g / mol to 8,000 g / mol and in particular 1,000 g / mol to 4,000 g / mol.

[0148] In this connection, the determination of the molecular weights (mass-average molar mass (Mw) and number-average molar mass (Mn)) of the polymers is generally carried out as outlined in more detail in the experimental part.

[0149] Preferably, the K value of the pyrrolidone-containing polymer (PP) (determined according to H. Fikentscher, Cellulose-Chemie 13, pp. 48-64 and 71-94 (1932)) is 5 to 35, more preferably 10 to 30, still more preferably 14 to 25 and in particular 15 to 22.

[0150] In a preferred embodiment, the reaction mixture (rM1) comprises water. The water comprising the reaction mixture (rM1) is stirred and heated under reflux, preferably for 0.2 to 5 hours, more preferably for 0.5 to 3 hours, and especially for 0.5 to 2 hours. After heating, water is preferably removed via distillation. The distillation can be carried out under normal pressure and by applying a vacuum.

[0151] In a preferred embodiment, the pyrrolidone-containing polymer (PP) is obtainable by polymerization of a reaction mixture (rM2), wherein the reaction mixture (rM2) comprises at least the following components:

[0152] (A) at least one itaconic acid derivative, preferably wherein component (A) is selected from the group consisting of itaconic acid, itaconic anhydride, itaconic esters and itaconic acid halides, and

[0153] (B) at least one amino acid of the general formula (1)

[0154] H2N-R1 -C(=O)-R 2 (1)

[0155] in

[0156] R 1 Selected from at least monosubstituted C2-C 20 Alkanediyl and at least monosubstituted C3-C 20 The group consisting of cycloalkanediyl, wherein the substituent is NH2;

[0157] R 2 Selected from Cl, Br and OR 3 The group consisting of

[0158] R 3 Choose from H, C1-C 10 Alkyl, C3-C 10 Cycloalkyl and C2-C 15 A group consisting of alkenyl.

[0159] Preferably,

[0160] R 1 Selected from at least monosubstituted C2-C 20 -alkanediyl group, wherein the substituent is NH2,

[0161] R 2 Selected from the group consisting of OH and Cl.

[0162] Particularly preferably,

[0163] R 1 Selected from C3-C 10 -alkanediyl, wherein the substituent is NH2, such as linear and saturated C4-alkanediyl, C5-alkanediyl or C6-alkanediyl, preferably C5-alkanediyl,

[0164] R 2 It's OH.

[0165] In a preferred embodiment, component (B) is selected from the group consisting of L-lysine, D-lysine and a racemic mixture of L-lysine and D-lysine. It is particularly preferred that component (B) is L-lysine.

[0166] In a preferred embodiment, the reaction mixture (rM2) comprises component (A) in a range of 0.5% to 70% by weight, preferably 5% to 70% by weight, more preferably 10% to 60% by weight and especially 20% to 50% by weight, based on the sum of the weight percentages of component (A) and the at least one component (B), preferably based on the total weight of the reaction mixture (rM2), and at least one component (B) in a range of 30% to 99.5% by weight, preferably 30% to 95% by weight, more preferably 40% to 90% by weight and especially 50% to 80% by weight.

[0167] In a preferred embodiment, the at least one itaconic acid derivative and the at least one amino acid of general formula (1) are present in the reaction mixture (rM2) in a molar ratio of 10:1 to 1:10, preferably 6:1 to 1:5 or 5:1 to 1:5, and in particular 4:1 to 1:2 or 3:1 to 1:5 or 3:1 to 1:2.

[0168] Preference is therefore given to pyrrolidone-containing polymers (PP) in which the molar ratio of component (A) to component (B) in the reaction mixture (rM2) is in the range from 3:1 to 1:2.

[0169] Furthermore, preference is given to pyrrolidone-containing polymers (PP) in which the molar ratio of component (A) to component (B) in the reaction mixture (rM2) is in the range from 3:1 to 1:10.

[0170] In this connection, the pyrrolidone-containing polymer (PP) preferably has a weight-average molecular weight (Mw; determined by gel permeation chromatography (GPC) with a 0.05 M aqueous ammonium formate / methanol mixture = 80:20 (volume parts) as eluent) of 500 g / mol to 100,000 g / mol, more preferably 1,000 g / mol to 5,0000 g / mol, still more preferably 1,000 g / mol to 10,000 g / mol and in particular 1,500 g / mol to 8,000 g / mol. Preferably, the pyrrolidone-containing polymer (PP) has a number average molecular weight (Mn; determined by gel permeation chromatography (GPC), as described above for Mw) of 500 to 20,000 g / mol, more preferably 500 to 10,000 g / mol, still more preferably 500 to 8,000 g / mol, and in particular 1,000 to 6,000 g / mol. Preferably, the pyrrolidone-containing polymer (PP) has a polydispersity (PD) in the range of 1.1 to 5, more preferably in the range of 1.1 to 4, and most preferably in the range of 1.1 to 3. The polydispersity (PD) is the ratio of the weight average molecular weight (Mw) to the number average molecular weight (Mn) of the pyrrolidone-containing polymer (PP). Preferably, the pyrrolidone-containing polymer (PP) has an amino value of 20 mg KOH / g to 500 mg KOH / g, more preferably 50 KOH / g to 450 KOH / g, and in particular 150 KOH / g to 400 KOH / g, determined by titration. Suitable titration methods are known to the skilled person and are described in further detail in the examples.

[0171] Unless otherwise stated, all weight % of components (A) and (B) and optionally component (C) are based on the total weight of the composition of the reaction mixture (rM2) before the start of the polymerization reaction.

[0172] As used in the context of the present invention, the phrase "the composition of the reaction mixture (rM2) before the start of polymerization" refers to the composition of the reaction mixture (rM2) before the components (A) and (B) and optionally the component (C) present in the reaction mixture (rM2) start to react with each other, i.e. before the start of polymerization and any reaction products are formed. The components (A) and (B) and optionally the component (C) present in the reaction mixture (rM2) are still in their unreacted form at this point in time. It should be understood that during the polymerization of the components (A) and (B) and optionally the component (C), these components react at least partially with each other, so that the ratios of these components to each other change.

[0173] As described above for the wt. % this "molar ratio" also relates to the molar ratio of component (A) to component (B) before the start of the polymerization reaction and thus before components (A) and (B) have reacted with one another.

[0174] The reaction mixture (rM2) may also comprise at least one catalyst as component (C).

[0175] As used in the context of the present invention, "at least one catalyst" refers to one catalyst as well as a mixture of two or more catalysts.

[0176] The terms "component (C)" and "at least one catalyst" are used synonymously within the context of the present invention and thus have the same meaning.

[0177] Suitable component (C) is a catalyst which catalyzes the reaction between component (A) and component (B). Examples of suitable catalysts are phosphoric acid, alkali metal dihydrogenphosphates, alkali metal hypophosphites, alkali metal hydrogensulfates, tin octoate, titanium (IV) butoxide and bismuth-2,2-diphenylundecanoate.

[0178] Therefore, preferably the reaction mixture (rM2) additionally comprises component (C), ie at least one catalyst selected from the group consisting of phosphoric acid, alkali metal dihydrogenphosphates, alkali metal hypophosphites, alkali metal hydrogensulfates, tin octoate, titanium(IV) butoxide and bismuth-2,2-diphenylundecanoate.

[0179] Titanium (IV) butoxide is also called Ti(OBu)4.

[0180] Alkali metal hypophosphites are preferred as component (C). Suitable alkali metal hypophosphites are known to those skilled in the art and are, for example but not limited to, selected from the group consisting of lithium hypophosphite, sodium hypophosphite and potassium hypophosphite. Sodium hypophosphite is particularly preferred as component (C).

[0181] For example, based on the sum of the weight percentages of components (A), (B) and (C), preferably based on the total weight of the reaction mixture (rM2), the reaction mixture (rM2) contains component (C) in an amount in the range of 0.1 wt % to 5 wt %, preferably in an amount in the range of 0.1 wt % to 3 wt %, particularly preferably in an amount in the range of 0.1 wt % to 2 wt %.

[0182] It will be apparent to the skilled person that the weight percentages (wt %) of components (A) and (B) and optionally component (C) generally add up to 100 wt %.

[0183] The polymerization of the reaction mixture (rM2) can be carried out in the presence of at least one solvent (S).

[0184] As used in the context of the present invention, "at least one solvent (S)" includes the use of one solvent (S) as well as a mixture of two or more solvents (S).

[0185] Suitable solvents (S) are known to those skilled in the art and are preferably solvents (S) that are inert to the components contained in the reaction mixture (rM2). Preferably, the at least one solvent (S) is selected from the group consisting of water, DMSO (dimethyl sulfoxide), NMP (N-methylpyrrolidone), butyl acetate, methyl ethyl ketone and mixtures thereof. Preferably, the at least one solvent (S) is water.

[0186] In various embodiments, the polymerization of the reaction mixture (rM2) is carried out at a temperature in the range of 50°C to 300°C, preferably in the range of 70°C to 250°C and particularly preferably in the range of 90°C to 240°C.

[0187] The polymerization can be carried out as a one-step process or as a multistep process. These processes are known to the person skilled in the art and are described in more detail below with regard to the process for producing the pyrrolidone-containing polymer (PP).

[0188] During the polymerization, components (A) and (B) undergo a polycondensation reaction to form the pyrrolidone-containing polymer (PP).

[0189] In a preferred embodiment, the pyrrolidone-containing polymer (PP) is biodegradable. Preferably, the pyrrolidone-containing polymer (PP) has a biodegradability of more than 20%, more preferably more than 30%, still more preferably more than 40%, and in particular more than 45% after 28 days (determined according to OECD 301F). It is also preferred that the pyrrolidone-containing polymer (PP) has a biodegradability of 20% to 100%, more preferably 30% to 99%, still more preferably 40% to 99% or 40% to 90% after 28 days (determined according to OECD 301F).

[0190] Preferably, the pyrrolidone-containing polymer (PP) comprises at least one unit of the general formula (A)

[0191]

[0192] in

[0193] R 4 Selected from at least monosubstituted C2-C 20 -alkanediyl and C3-C 20 -cycloalkanediyl, wherein at least one substituent is C(=O)R 2 ,in

[0194] R 2Selected from Cl, Br and OR 3 The group consisting of

[0195] R 3 Choose from H, C1-C 10 -alkyl, C3-C 10 -cycloalkyl and C2-C 15 -alkenyl group.

[0196] R 4 Preferably selected from at least monosubstituted C2-C 20 -alkanediyl, wherein at least one substituent is C(=O)R 2 ,in

[0197] R 2 Selected from the group consisting of OH and Cl.

[0198] R 4 Most preferably selected from the group consisting of monosubstituted C3-C 10 -alkanediyl group, wherein the substituent is C(=O)OH. In the above embodiment, R 4 Preferably it is C4-alkanediyl, C5-alkanediyl or C6-alkanediyl, preferably linear and saturated, most preferably linear and saturated C5-alkanediyl.

[0199] In a preferred embodiment, the aqueous polymer dispersion comprises a (co)polymer selected from the group consisting of acrylate polymers, acrylic acid-styrene copolymers, styrene-butadiene-based copolymers, vinyl acetate polymers and ethylene-vinyl acetate copolymers, preferably a (co)polymer selected from the group consisting of acrylic acid-styrene copolymers, styrene-butadiene-based copolymers and ethylene-vinyl acetate copolymers, more preferably an acrylic acid-styrene copolymer.

[0200] The (co)polymers of the aqueous polymer dispersions are preferably composed of ethylenically unsaturated compounds in polymerized form. The preparation of these polyaddition compounds is usually carried out by metal complex-catalyzed, anion-catalyzed, cation-catalyzed and particularly preferably free-radical-catalyzed polymerization of ethylenically unsaturated compounds, as is familiar to the person skilled in the art.

[0201] The free-radically catalyzed polymerization of ethylenically unsaturated compounds is generally known to the person skilled in the art and is carried out in particular by free-radically bulk, emulsion, solution, precipitation or suspension polymerization processes, particular preference being given to free-radically initiated aqueous emulsion polymerization.

[0202] The free-radical initiated emulsion polymerization of ethylenically unsaturated compounds (monomers) in aqueous medium is known [cf. Emulsion polymerization in Encyclopedia of Polymer Science and Engineering, Vol. 8, p. 659 ff. (1987); DC Blackley, in High Polymer Latices, Vol. 1, p. 35 ff. (1966); H. Warson, The Applications of Synthetic Resin Emulsions, Chapter 5, p. 246 ff. (1972); D. Diederich, Chemie in unserer Zeit, 24, pp. 135 to 142 (1990); Emulsion Polymerisation, Interscience Publishers, New York (1965); DE-A 40 03 422 and Dispersionen synthetischer Hochpolymerer, F. Springer-Verlag, Berlin (1969)]. Free-radical initiated aqueous emulsion polymerization is usually carried out by dispersing the monomers (usually with the use of dispersants such as emulsifiers and / or protective colloids) in an aqueous medium and polymerizing them with the aid of at least one water-soluble free-radical polymerization initiator. Usually, the residual content of unreacted monomers in the aqueous polymer dispersion obtained is reduced by chemical and / or physical aftertreatment, the polymer solids content is set to the desired value by dilution or concentration, or other conventional additives such as foam or viscosity-modifying additives are added to the aqueous polymer dispersion.

[0203] Possible monomers are, in particular, monomers which can be free-radically polymerized in a simple manner, for example ethylene, vinylaromatic monomers such as styrene, α-methylstyrene or o-chlorostyrene, vinyl acetate, acrylic acid, esters of acrylic acid and methacrylic acid with alkanols, the alkanols generally having 1 to 12, preferably 1 to 8 and in particular 1 to 4 carbon atoms, in particular methyl, ethyl, n-butyl, isobutyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl (for example hydroxyethyl methacrylate)), esters of acrylic acid and methacrylic acid with alkanes, the alkanes generally having 1 to 12, preferably 1 to 10 and in particular 1 to 8 carbon atoms (for example ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, 2-propylheptyl acrylate) and 1,3-butadiene. When preparing the polymer dispersion, the monomers mentioned usually form the main monomers, which total a proportion of ≥50% by weight, preferably ≥80% by weight and particularly preferably ≥90% by weight, based on the amount of all ethylenically unsaturated compounds used to prepare the polymer dispersion (total amount of monomers). In general, these monomers have only moderate to low solubility in water under standard conditions [20° C., 1 atm (=1.013 bar absolute pressure)].

[0204] In a preferred embodiment, the aqueous polymer dispersion comprises an acrylic acid-styrene copolymer. Suitably, the acrylic acid-styrene copolymer is obtainable by free radical polymerization of styrene and / or methylstyrene, especially styrene, with an acrylate selected from the group consisting of methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, hydroxyethyl methacrylate, 2-propylheptyl acrylate and mixtures thereof, especially selected from the group consisting of 2-ethylhexyl acrylate, hydroxyethyl methacrylate, butyl acrylate and mixtures thereof. In this connection, it is understood that methylstyrene generally refers to α-methylstyrene, β-methylstyrene, 2-methylstyrene, 3-methylstyrene and 4-methylstyrene, preferably to α-methylstyrene.

[0205] Preferably, the acrylic acid-styrene copolymer is obtainable by free radical polymerization of 15% to 50% by weight, more preferably 20% to 45% by weight, and especially 25% to 40% by weight of styrene and / or methylstyrene and 50% to 85% by weight, more preferably 55% to 80% by weight, and especially 60% to 75% by weight of at least one acrylic acid ester. In this connection, it is preferred that styrene is polymerized with at least one acrylic acid ester selected from the group consisting of methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, hydroxyethyl methacrylate, 2-propylheptyl acrylate and mixtures thereof, especially selected from the group consisting of 2-ethylhexyl acrylate, hydroxyethyl methacrylate, butyl acrylate and mixtures thereof.

[0206] In a preferred embodiment, the aqueous polymer dispersion comprises a styrene-butadiene based copolymer.

[0207] In a preferred embodiment, the aqueous polymer dispersion comprises a vinyl acetate polymer.

[0208] In a preferred embodiment, the aqueous polymer dispersion comprises a terpolymer. Suitable terpolymers are addition products of vinyl acetate, ethylene and vinyl esters. Preferably, the vinyl ester is a vinyl ester of a carboxylic acid having 1 to 15 carbon atoms. Preferred are vinyl acetate, vinyl propionate, vinyl butyrate, vinyl 2-ethylhexanoate, vinyl laurate, 1-methylvinyl acetate, vinyl pivalate and vinyl esters of α-branched monocarboxylic acids having 9 to 11 carbon atoms, examples of which are sold under the trade name VeoVa. TM 9 or VeoVa TM 10. Vinyl acetate is particularly preferred.

[0209] In a preferred embodiment, the aqueous polymer dispersion has a solid polymer content of 20% to 70% by weight, more preferably 25% to 72% by weight, even more preferably 30% to 65% by weight, in particular 50% to 62% by weight or 45% to 55% by weight or 52% to 62% by weight, determined to DIN EN ISO 3251, based on the total weight of the aqueous polymer dispersion.

[0210] In a preferred embodiment, the pH of the aqueous polymer dispersion is from 6 to 10, preferably from 7 to 9, in particular from 7 to 8.

[0211] In a preferred embodiment, the Tg (glass transition temperature) of the (co)polymer of the aqueous polymer dispersion is from -60°C to 35°C, preferably from -50°C to 25°C, more preferably from -40°C to 20°C, in particular from -30°C to 10°C or from -25°C to 0°C or from -5°C to 20°C, the Tg being calculated using the Fox equation. According to Fox (cf. TG Fox, Bull. Am. Phys. Soc. (Ser II) 1, 123,

[1956] and Ullmanns der technischen Chemie, Weinheim (1980), S. 17, 18), the following equation is a suitable approximation for the Tg of polymer dispersions:

[0212]

[0213] Where X 1 , X 2. …, X n is the mass fraction 1, 2, ..., n and Tg 1 , Tg 2 ,…,Tg n is the glass transition temperature in Kelvin of the homopolymer of each monomer 1, 2, ..., n. The respective Tg is known, for example, from Ullmann's Encyclopedia of Industrial Chemistry, VCH, Weinheim, Vol. A 21 (1992), p. 169 and from J. Brandrup, EH Immergut, Polymer Handbook 3rd edition, J. Wiley, New York 1989.

[0214] In a preferred embodiment, the (co)polymer has a minimum film forming temperature (MFFT; determined according to DIN ISO 2115) of -20 to 20°C, preferably -15 to 15°C, more preferably -10 to 10°C, in particular -5 to 5°C.

[0215] In a preferred embodiment, the (co)polymer of the aqueous polymer dispersion has an average particle size (D50 value) of the polymer particles as measured by dynamic light scattering (e.g. determined according to ISO 22412:2008) of 50 nm to 1000 nm, preferably 100 nm to 900 nm, more preferably 150 nm to 750 nm or 700 nm to 900 nm.

[0216] The aqueous polymer dispersion may additionally comprise at least one surface-active compound. The surface-active compound is used to stabilize the aqueous dispersion of the polymer by keeping the polymer particles dispersed. The surface-active compound may be an emulsifier, a protective colloid or a mixture of the two. The emulsifier and the protective colloid are usually different from each other in their weight-average molar mass Mw. Emulsifiers usually have a weight-average molar mass Mw lower than 2000, while the weight-average molar mass Mw of protective colloids can be up to 50 000, especially higher than 2000 to up to 50000. Typically, based on the total amount of polymer in the aqueous polymer dispersion, the amount of the surface-active compound is in the range of 0.1 wt % to 10 wt %, especially in the range of 0.5 wt % to 5 wt %.

[0217] Preferably, the surface-active compound comprises one or more emulsifiers. Emulsifiers are nonionic, anionic or cationic. In the case of using emulsifier mixtures, their compatibility must be ensured, which can be evaluated by preliminary tests if in doubt. Usually, anionic emulsifiers are compatible with another anionic emulsifier or a nonionic emulsifier. Similarly, cationic emulsifiers are usually compatible with another cationic emulsifier or a nonionic emulsifier. Preferably, the emulsifier is an anionic emulsifier, a combination of two or more anionic emulsifiers or a combination of at least one anionic emulsifier and at least one nonionic emulsifier. Nonionic emulsifiers are, for example, ethoxylated C8-C8 emulsifiers with a degree of ethoxylation of 3 to 50 (=ethylene oxide units [EO]: 3-50). 36 Fatty alcohols and ethoxylated mono-C4-C 12 Alkylphenol, di-C4-C 12 Alkylphenol and tri-C4-C 12 Examples of conventional nonionic emulsifiers are Eumulgin B grade (cetyl alcohol / stearyl alcohol ethoxylates, RTM BASF), Dehydol LS grade (fatty alcohol ethoxylates, EO units: 1-10, RTM BASF), Lutensol A grade (C 12 C 14 - Fatty alcohol ethoxylate, EO units: 3-8, RTM BASF), Lutensol AO grade (C 13 C 15 -oxo alcohol ethoxylates, EO units: 3-30), Lutensol AT grade (C 16 C 18 - fatty alcohol ethoxylates, EO units: 11-80), Lutensol ON grades (C10-oxo alcohol ethoxylates, EO units: 3-11) and Lutensol TO grades (C 13-oxo alcohol ethoxylate, EO units: 3-20). Here and hereinafter, the phrase "EO unit" means the average number of ethylene oxide repeating units in the emulsifier. Anionic emulsifiers include, for example, alkali metal salts of dialkyl esters of sulfosuccinic acid, C8-C 12 Alkali metal and ammonium salts of alkyl sulfates, C 12 -C 18 Alkali metal and ammonium salts of alkylsulfonic acids, C9-C 18 Alkali metal and ammonium salts of alkylarylsulfonic acids, ethoxylated C 12 -C 18 Sulfate monoesters of alkanols (EO units: 4-30) or ethoxylated (C4-C 12 Alkali metal salts and ammonium salts of sulfuric acid monoesters of (alkyl) phenol (EO units: 3-50).

[0218] Other suitable anionic emulsifiers include, but are not limited to, fatty alcohol phosphates, alkylphenol phosphates, alkyl polyglycol ether phosphates, alkyl polyoxyalkylene phosphates and fatty alcohol ether phosphates and their salts, especially their alkali metal salts and ammonium salts, particularly preferably alkali metal salts such as sodium salts.

[0219] A comprehensive description of suitable emulsifiers can be found in Houben-Weyl, Methoden der organischen Chemie, Volume XIV / 1, Makromolekulare Stoffe, Georg-Thieme-Verlag, Stuttgart, 1961, pages 192 to 208.

[0220] Similar to the aforementioned emulsifiers, suitable protective colloids may be nonionic, anionic or cationic. Examples of protective colloids are poly(vinyl alcohol), poly(alkylene glycol), poly(acrylic acid) and its alkali metal salts, poly(methacrylic acid) and its alkali metal salts and gelatin derivatives. Anionic protective colloids may also be copolymers containing an appropriate amount of at least one anionic monomer in polymerized form, such as acrylic acid, methacrylic acid, maleic acid, 2-acrylamido-2-methylpropanesulfonic acid, p-vinylphenylsulfonic acid or their salt forms, preferably their alkali metal salts. Examples of cationic protective colloids are homopolymers and copolymers containing sufficient amounts of cationic monomers, especially monoethylenically unsaturated monomers having one or more N-protonated or N-alkylated amino groups.

[0221] Protective colloids differ from polymers dispersed in aqueous polymer dispersions in that they are water-soluble or water-dispersible. The term "water-soluble or water-dispersible" is understood to mean that the corresponding protective colloid can be dissolved or dispersed in deionized water at 20° C. and 1013 mbar in an amount of at least 10 g / L of polymer, preferably such that the resulting aqueous solution has no measurable particles or has particles with a size of at most 20 nm as determined by dynamic light scattering according to DIN 22412:2008.

[0222] A comprehensive description of suitable protective colloids can be found in Houben-Weyl, Methoden der organischen Chemie, Volume XIV / 1, Makromolekulare Stoffe, Georg-Thieme-Verlag, Stuttgart, 1961, pages 411 to 420.

[0223] As indicated above, the present invention further relates in a second aspect to a method of making a redispersible dispersion powder (RDP), the method comprising the steps of:

[0224] i) a pyrrolidone-containing polymer (PP) comprising at least one unit of the general formula (I) to (III)

[0225]

[0226] wherein R is independently hydrogen, C1-C4-alkyl, or two groups R are linked to each other to form a six-membered ring;

[0227] X is -O- or -NR;

[0228] A is independently selected from C1-C 20 -alkanediyl, C3-C 20 -cycloalkanediyl and C6-C 20 - a group consisting of an arylene group,

[0229] Among them, C1-C 20 -alkanediyl is optionally interrupted by one or more non-adjacent oxygen atoms, sulfur atoms or functional groups -NR-, -CO-, -CO-O-, -CO-NR-, -SO- or -SO2-, in which the nitrogen atom is optionally protonated or quaternized,

[0230] Among them, C1-C 20 -alkanediyl and the C3-C 20 -cycloalkanediyl optionally carries at least one selected from C(=O)R 2 and SO3H, where

[0231] R 2Selected from Cl, Br and OR 3 The group consisting of

[0232] R 3 Choose from H, C1-C 10 Alkyl, C3-C 10 Cycloalkyl and C2-C 15 The group consisting of alkenyl groups,

[0233] Among them, C6-C 20 -arylene is optionally inserted with oxygen, sulfur, -NR-, -SO- or -SO2- and is optionally substituted with -COOH or -SO3H or a mixture of these groups;

[0234] Z is a group of formula (IV)

[0235]

[0236] Where B is C1-C 20 -alkanediyl, C6-C 20 -cycloalkanediyl or a mixture of such groups, the C1-C 20 -alkanediyl optionally interrupted by one or more non-adjacent oxygen atoms, sulfur atoms or functional groups -NR-, -CO-, -CO-O-, -CO-NR-, -SO- or -SO2-, and optionally carrying an additional functional group -COOH or -SO3H, in which the nitrogen atom of the functional group -NR- is optionally protonated or quaternized

[0237] Or Z is a mixture of a group of formula (IV) and a group A

[0238] mixing with an aqueous polymer dispersion, the aqueous polymer dispersion preferably comprising a (co)polymer selected from the group consisting of acrylate polymers, acrylic acid-styrene copolymers, styrene-butadiene based copolymers, vinyl acetate polymers and ethylene-vinyl acetate copolymers;

[0239] ii) spray drying the mixture obtained in step i).

[0240] Preferred embodiments (e.g. with regard to the pyrrolidone-containing polymer (PP), the aqueous polymer dispersion and the amounts of the ingredients) have already been disclosed above with respect to the pyrrolidone-containing polymer (PP) and its use as a spray drying aid and apply analogously to the process for producing an RDP. This applies in particular to the preferred definitions of A and B. Particularly preferred embodiments of the process are disclosed (again) below.

[0241] In a preferred embodiment, the pyrrolidone-containing polymer (PP) is obtainable by polymerization of a reaction mixture (rM1), wherein the reaction mixture (rM1) comprises at least the following components:

[0242] (A) at least one itaconic acid derivative, preferably wherein component (A) is selected from the group consisting of itaconic acid, itaconic anhydride, itaconic esters and itaconic acid halides, and

[0243] (B) at least one diamine, preferably wherein the diamine is selected from the group consisting of ethylenediamine, 1,3-diaminopropane, 1,4-diaminobutane, 1,5-pentanediamine, 1,6-diaminohexane, 1,7-diaminoheptane, 1,8-diaminooctane and 1,9-diaminononane, more preferably selected from ethylenediamine and 1,5-pentanediamine.

[0244] In a preferred embodiment, the reaction mixture (rM1) comprises at least two diamines, preferably selected from the group consisting of ethylenediamine, 1,3-diaminopropane, 1,4-diaminobutane, 1,5-pentanediamine, 1,6-diaminohexane and 1,7-diaminoheptane, and in particular wherein the reaction mixture (rM1) comprises ethylenediamine and 1,5-pentanediamine.

[0245] In a preferred embodiment, the pyrrolidone-containing polymer (PP) is obtainable by polymerization of a reaction mixture (rM2), wherein the reaction mixture (rM2) comprises at least the following components:

[0246] (A) at least one itaconic acid derivative, preferably wherein component (A) is selected from the group consisting of itaconic acid, itaconic anhydride, itaconic esters and itaconic acid halides, and

[0247] (B) at least one amino acid of the general formula (1)

[0248] H2N-R 1 -C(=O)-R 2 (1)

[0249] in

[0250] R 1 Selected from at least monosubstituted C2-C 20 -alkanediyl and at least monosubstituted C3-C 20 - the group consisting of cycloalkanediyl, wherein the substituent is NH2, such as linear and saturated C4-alkanediyl, C5-alkanediyl or C6-alkanediyl, preferably C5-alkanediyl;

[0251] R 2 Selected from Cl, Br and OR 3 The group consisting of

[0252] R 3 Choose from H, C1-C 10 Alkyl, C3-C 10 Cycloalkyl and C2-C15 The group consisting of alkenyl groups, preferably wherein component (B) is selected from the group consisting of L-lysine, D-lysine and a racemic mixture of L-lysine and D-lysine.

[0253] In a preferred embodiment, in step i), the pyrrolidone-containing polymer (PP) is mixed with the aqueous polymer dispersion in an amount of 4 to 20% by weight, preferably 5 to 15% by weight, in particular 6 to 12% by weight, based on the solids content of the aqueous polymer dispersion.

[0254] In step ii) any suitable apparatus may be used.

[0255] In a preferred embodiment, the aqueous dispersion is sprayed through a two-fluid nozzle.

[0256] In a preferred embodiment, the inlet temperature of the dryer gas is from 100 to 200°C, preferably from 105 to 190°C, more preferably from 110 to 180°C, especially from 115 to 160°C.

[0257] In a preferred embodiment, the outlet temperature of the dryer gas is from 40 to 90°C, preferably from 45 to 85°C, more preferably from 50 to 80°C, especially from 55 to 75°C.

[0258] As indicated above, the present invention further relates in a third aspect to a redispersible dispersion powder (RDP) obtained by the method for making a redispersible dispersion powder (RDP) as outlined above.

[0259] Preferred embodiments (e.g. regarding pyrrolidone-containing polymers (PP), aqueous polymer dispersions, ingredient amounts and methods for making RDP) have been disclosed above with respect to pyrrolidone-containing polymers (PP) and their use as spray drying aids and methods for making RDP, and also apply analogously to RDP.

[0260] As indicated above, the present invention further relates in a fourth aspect to a redispersible dispersion powder (RDP) comprising a (co)polymer and a pyrrolidone-containing polymer (PP), the (co)polymer being selected from the group consisting of acrylate polymers, acrylic acid-styrene copolymers, styrene-butadiene-based copolymers, vinyl acetate polymers and ethylene-vinyl acetate copolymers, and the pyrrolidone-containing polymer (PP) comprising at least one unit of the general formula (I) to (III)

[0261]

[0262] wherein R is independently hydrogen, C1-C4-alkyl, or two groups R are linked to each other to form a six-membered ring;

[0263] X is -O- or -NR;

[0264] A is independently selected from C1-C 20 -alkanediyl, C3-C 20 -cycloalkanediyl and C6-C 20 - a group consisting of an arylene group,

[0265] Among them, C1-C 20 -alkanediyl is optionally interrupted by one or more non-adjacent oxygen atoms, sulfur atoms or functional groups -NR-, -CO-, -CO-O-, -CO-NR-, -SO- or -SO2-, in which the nitrogen atom is optionally protonated or quaternized,

[0266] Among them, C1-C 20 -alkanediyl and the C3-C 20 -cycloalkanediyl optionally carries at least one selected from C(=O)R 2 and SO3H, where

[0267] R 2 Selected from Cl, Br and OR 3 The group consisting of

[0268] R 3 Choose from H, C1-C 10 Alkyl, C3-C 10 Cycloalkyl and C2-C 15 The group consisting of alkenyl groups,

[0269] Among them, C6-C 20 -arylene is optionally inserted with oxygen, sulfur, -NR-, -SO- or -SO2- and is optionally substituted with -COOH or -SO3H or a mixture of these groups;

[0270] Z is a group of formula (IV)

[0271]

[0272] Where B is C1-C 20 -alkanediyl, C6-C 20 -cycloalkanediyl or a mixture of such groups, the C1-C 20-alkanediyl optionally interrupted by one or more non-adjacent oxygen atoms, sulfur atoms or functional groups -NR-, -CO-, -CO-O-, -CO-NR-, -SO- or -SO2-, and optionally carrying an additional functional group -COOH or -SO3H, in which the nitrogen atom of the functional group -NR- is optionally protonated or quaternized

[0273] Alternatively, Z is a mixture of a group of formula (IV) and a group A.

[0274] In a preferred embodiment, the pyrrolidone-containing polymer (PP) is obtainable by polymerization of a reaction mixture (rM1), wherein the reaction mixture (rM1) comprises at least the following components:

[0275] (A) at least one itaconic acid derivative, preferably wherein component (A) is selected from the group consisting of itaconic acid, itaconic anhydride, itaconic esters and itaconic acid halides, and

[0276] (B) at least one diamine, preferably wherein the diamine is selected from the group consisting of ethylenediamine, 1,3-diaminopropane, 1,4-diaminobutane, 1,5-pentanediamine, 1,6-diaminohexane, 1,7-diaminoheptane, 1,8-diaminooctane and 1,9-diaminononane, more preferably selected from ethylenediamine and 1,5-pentanediamine.

[0277] In a preferred embodiment, the reaction mixture (rM1) comprises at least two diamines, preferably selected from the group consisting of ethylenediamine, 1,3-diaminopropane, 1,4-diaminobutane, 1,5-pentanediamine, 1,6-diaminohexane and 1,7-diaminoheptane, and in particular wherein the reaction mixture (rM1) comprises ethylenediamine and 1,5-pentanediamine.

[0278] In a preferred embodiment, the pyrrolidone-containing polymer (PP) is obtainable by polymerization of a reaction mixture (rM2), wherein the reaction mixture (rM2) comprises at least the following components:

[0279] (A) at least one itaconic acid derivative, preferably wherein component (A) is selected from the group consisting of itaconic acid, itaconic anhydride, itaconic esters and itaconic acid halides, and

[0280] (B) at least one amino acid of the general formula (1)

[0281] H2N-R 1 -C(=O)-R 2 (1)

[0282] in

[0283] R 1 Selected from at least monosubstituted C2-C 20-alkanediyl and at least monosubstituted C3-C 20 - the group consisting of cycloalkanediyl, wherein the substituent is NH2, such as linear and saturated C4-alkanediyl, C5-alkanediyl or C6-alkanediyl, preferably C5-alkanediyl;

[0284] R 2 Selected from Cl, Br and OR 3 The group consisting of

[0285] R 3 Choose from H, C1-C 10 Alkyl, C3-C 10 Cycloalkyl and C2-C 15 The group consisting of alkenyl groups, preferably wherein component (B) is selected from the group consisting of L-lysine, D-lysine and a racemic mixture of L-lysine and D-lysine.

[0286] As indicated above, the present invention further relates in a fifth aspect to a method of making a powder paint or coating, the method comprising blending the redispersible dispersion powder (RDP) as outlined above with a pigment.

[0287] Preferred embodiments (e.g. with regard to the pyrrolidone-containing polymer (PP), the aqueous polymer dispersion and the amounts of the ingredients) have been outlined above in the use of the pyrrolidone-containing polymer (PP) as a spray drying aid and in the process for producing RDP and will also apply to powder coatings or coatings. Particularly preferred embodiments are mentioned below.

[0288] In a preferred embodiment, the powder coating comprises at least one inorganic pigment and / or at least one organic pigment. These may be selected from those disclosed below.

[0289] Preferably, the powder coating comprises an inorganic white pigment, more preferably selected from the group consisting of titanium dioxide, preferably in rutile form, barium sulfate, zinc oxide, zinc sulfide, basic lead carbonate, antimony trioxide and lithopone (zinc sulfide and barium sulfate), or an inorganic colored pigment, more preferably selected from the group consisting of iron oxide, carbon black, graphite, zinc yellow, zinc green, ultramarine, manganese black, antimony black, manganese violet, Prussian blue and Paris green, in particular titanium dioxide.

[0290] Preferably, the powder coating comprises organic pigments. Suitable organic color pigments are, for example, sepia, gamboge, Cassel brown, toluidine red, para red, Hansa yellow, indigo, azo dyes, anthraquinones and indigoid dyes as well as dioxazines, quinacridones, phthalocyanines, isoindolinones and metal complex pigments. Also useful are BASF SE's Brands, e.g. yellow, Brown and In a preferred embodiment, the powder coating comprises an organic pigment, wherein the organic pigment is in the form of hollow organic particles and / or is based on a polymer comprising a nonionic ethylenically unsaturated monomer, preferably wherein the nonionic ethylenically unsaturated monomer is selected from the group consisting of styrene, acrylonitrile, methacrylamide, methyl methacrylate, ethyl acrylate, ethyl methacrylate, butyl acrylate, butyl methacrylate, 2-ethylhexyl acrylate, 2-ethylhexyl methacrylate or mixtures thereof.

[0291] The coatings or coatings of the invention are produced in a known manner by blending the components in a conventional mixer. A tried and tested procedure is to first prepare an aqueous paste or dispersion from pigment, water and optional auxiliaries and then mix the polymer binder (i.e., an aqueous dispersion of a polymer, usually) with the pigment paste and the pigment dispersion, respectively.

[0292] The coatings or coatings of the invention can be applied to the substrate in a customary manner, for example by brushing, spraying, dipping, rolling or knife coating.

[0293] In a preferred embodiment, the method comprises

[0294] a) 8 to 20% by weight of at least one pigment and

[0295] b) 10 to 19 wt. % of at least one redispersible dispersion powder (RDP), the at least one redispersible dispersion powder (RDP) comprising

[0296] i) at least one (co)polymer selected from the group consisting of acrylate polymers, acrylic acid-styrene copolymers, styrene-butadiene based copolymers, vinyl acetate polymers and ethylene-vinyl acetate copolymers, preferably acrylic acid-styrene copolymers, and

[0297] ii) at least one pyrrolidone-containing polymer (PP),

[0298] c) 55% to 78% by weight of at least one filler,

[0299] d) 0.2% to 2% by weight of at least one dispersant,

[0300] d) 0.5 to 2% by weight of at least one thickener and

[0301] e) 0.5 wt % to 2 wt % of at least one defoaming agent blended,

[0302] Each is based on the total dry weight of the powder coating.

[0303] The powder coating obtained via the process described above is particularly suitable as an interior coating.

[0304] In a preferred embodiment, the method comprises

[0305] a) 21 to 30% by weight of at least one pigment,

[0306] b) 15 to 25 wt. % of at least one redispersible dispersion powder (RDP), the at least one redispersible dispersion powder (RDP) comprising

[0307] i) at least one (co)polymer selected from the group consisting of acrylate polymers, acrylic acid-styrene copolymers, styrene-butadiene based copolymers, vinyl acetate polymers and ethylene-vinyl acetate copolymers, preferably acrylic acid-styrene copolymers, and

[0308] ii) at least one pyrrolidone-containing polymer (PP),

[0309] c) 40% to 54% by weight of at least one filler,

[0310] d) 0.2% to 2% by weight of at least one dispersant,

[0311] d) 0.5 to 2% by weight of at least one thickener and

[0312] e) 0.5 wt % to 2 wt % of at least one defoaming agent blended,

[0313] Each is based on the total dry weight of the powder coating.

[0314] The powder coating obtained via the process described above is particularly suitable as an exterior coating.

[0315] In a preferred embodiment, the method comprises

[0316] b) 2 to 30% by weight of at least one pigment and

[0317] b) 10% to 25% by weight of at least one redispersible dispersion powder (RDP), the at least one redispersible dispersion powder (RDP) comprising

[0318] i) at least one (co)polymer selected from the group consisting of acrylate polymers, acrylic acid-styrene copolymers, styrene-butadiene based copolymers, vinyl acetate polymers and ethylene-vinyl acetate copolymers, preferably acrylic acid-styrene copolymers, and

[0319] ii) at least one pyrrolidone-containing polymer (PP),

[0320] c) 40% to 78% by weight of at least one filler,

[0321] d) 0.2% to 2% by weight of at least one dispersant,

[0322] d) 0.5 to 2% by weight of at least one thickener and

[0323] e) 0.5 wt % to 2 wt % of at least one defoaming agent blended,

[0324] Each is based on the total dry weight of the coating.

[0325] Suitable fillers include, for example, matting agents, which significantly reduce the gloss in the desired manner. Matting agents are usually transparent and can be both organic and inorganic. Inorganic fillers based on silica are most suitable and are widely commercially available. Examples are WR Grace & Company's Brands and Evonik Industries AG. Brand. Organic matting agents such as Brand and The brand is obtained from BYK-Chemie GmbH and is marketed under the name Deuteron The brand is available from Deuteron GmbH. Fillers suitable for emulsion paints also include aluminosilicates such as feldspar; silicates such as kaolin, talc, mica, magnesite; alkaline earth metal carbonates such as calcium carbonate (for example in the form of calcite or chalk), magnesium carbonate, dolomite; alkaline earth metal sulfates such as calcium sulfate; silicon dioxide, etc. Finely divided fillers are naturally preferred in the paint. Fillers can be used as individual components. However, in practice, filler mixtures have been found to be particularly advantageous, examples being calcium carbonate / kaolin and calcium carbonate / talc. Gloss paints usually include only minimal amounts of very finely divided fillers or are completely free of fillers.

[0326] Finely divided fillers may also be used to enhance opacity and / or conserve white pigment. Blends of fillers and color pigments are preferably used to control opacity and chroma (color intensity) of hue / color.

[0327] In a preferred embodiment, the at least one filler is selected from the group consisting of calcium carbonate, precipitated calcium carbonate, talc, mica, silica, aluminum silicate, nepheline syenite, clay, calcined clay, feldspar and mixtures thereof.

[0328] Suitable dispersants are, for example, alkali metal and ammonium salts of sodium polyphosphate, potassium polyphosphate, ammonium polyphosphate, (meth) acrylic acid copolymers or maleic anhydride copolymers, polyphosphonates (such as sodium 1-hydroxyethane-1,1-diphosphonate) and naphthalenesulfonates, especially their sodium salts. In a preferred embodiment, the at least one dispersant is a sodium salt of a carboxylic acid copolymer in water or a copolymer of maleic acid and an olefin as a sodium salt, preferably a sodium salt of a carboxylic acid copolymer in water. The dispersant may be present in the powder coating in an amount of 0.1% to 2% by weight, preferably 0.2% to 1% by weight, based on the total amount of the formulation. Preferably, the amount is adjusted according to the filler used.

[0329] Suitable defoamers are, for example, hydrophobic materials such as silicones, polysiloxanes, mineral oils, vegetable oils and white oils, which are often provided in powder form in combination with surface-active substances (eg FoamStar PB 2922) and usually bound to a carrier substance such as silicon dioxide (eg Agitan P 804).

[0330] In a preferred embodiment, the at least one defoaming agent is a modified polysiloxane.

[0331] Useful thickeners include, for example, associative thickeners, such as polyurethane thickeners. The amount of thickener is preferably less than 2.5% by weight, more preferably less than 1.5% by weight of thickener, based on the coating solids content. Further guidance on wood coating formulations is described in detail in "Water based acrylates for decorative coatings", ISBN 3-87870-726-6, by authors M. Schwartz and R. Baumstark. Other suitable thickeners include, for example, acrylic thickeners, cellulose ethers, chemically modified cellulose derivatives (cellulose products - hydroxyethyl cellulose (HEC), carboxymethyl cellulose (CMC), hydroxypropyl methylcellulose, methylcellulose, hydroxypropyl cellulose, ethyl hydroxyethyl cellulose and other chemically substituted cellulose macromolecules), hydrophobically modified polyethers (HMPE), gums, sugars, polysaccharides and polyvinyl alcohol.

[0332] In a preferred embodiment, the at least one thickener is hydroxyethylcellulose (HEC), preferably having a weight average molecular weight (Mw; determined by gel permeation chromatography (GPC) with a 0.05 M aqueous ammonium formate / methanol mixture = 80:20 (volume parts) as eluent) of 1,000 to 100,000 g / mol, more preferably 5,000 to 60,000 g / mol, still more preferably 10,000 to 50,000 g / mol, and especially 15,000 to 25,000 g / mol.

[0333] Film formers may be further blended into the powder coating. Suitable film forming aids include, for example, but not limited to, and glycol ethers and esters, such as, for example, those from BASF SE under the trade name and and from Dow Chemicals under the trade name Commercially available glycol ethers and esters. The amount is preferably <10% by weight and more preferably <5% by weight, based on the total formulation. It is also possible to formulate completely without solvents and / or film formers.

[0334] A wetting agent may further be included and blended. Suitable wetting agents include, for example, nonionic surfactants, such as nonionic ethoxylated fatty alcohol-based surfactants or nonionic propoxylated fatty alcohol-based surfactants (e.g., Lumiten N-OG). The wetting agent may be present in the powder coating in an amount of 0.1 wt % to 2 wt %, preferably 0.2 wt % to 1 wt %, based on the total amount of the formulation. Preferably, the amount is adjusted according to the filler used.

[0335] Further information on coating formulations can be found in the following references: the textbook “Additives for Waterborne Coatings” by Wernfried Heilen et al.; Vincentz-Verlag 2021; 978-3-7486-0486-0 (ISBN) and Waterbased Acrylates for Decorative Coatings from Manfred Schwartz, Roland Baumstark; Vincentz Press, 2001, Chapter 2).

[0336] As indicated above, the present invention further relates in a sixth aspect to a method of making a construction material composition, the method comprising blending the redispersible dispersion powder (RDP) as outlined above with cement.

[0337] All preferred embodiments disclosed above in relation to other aspects of the invention apply analogously to this particular aspect.

[0338] As used herein, the term "cement" encompasses concrete and mortar.

[0339] The term "concrete" refers to a mortar to which coarse particles, i.e. particles with a diameter greater than 5 mm, are added. The term "mortar" or "mortar" refers to a cement paste to which fine particles, i.e. particles with a diameter between 150 pm and 5 mm (e.g. sand), and optionally very fine particles are added. Mortar is a sufficiently low viscosity mixture for filling voids or gaps. The viscosity of the mortar is high enough to support not only the weight of the mortar itself, but also the weight of the masonry placed on it. The term "cement paste" refers to an inorganic binder composition mixed with water.

[0340] Aggregates in the present invention can be, for example, silica, quartz, sand, crushed marble, glass spheres, granite, limestone, sandstone, calcite, marble, serpentine, travertine, dolomite, feldspar, gneiss, alluvial sand, any other durable aggregates and mixtures thereof. Aggregates are also often referred to as fillers and do not act, in particular, as binders.

[0341] Suitable inorganic binders are selected from the group consisting of hydraulic binders, latent hydraulic binders, binders based on calcium sulfate and mixtures thereof.

[0342] As indicated above, the present invention further relates in a seventh aspect to a pyrrolidone-containing polymer (PP) obtainable by polymerization of a reaction mixture (rM2), wherein the reaction mixture (rM2) comprises at least the following components:

[0343] (A) at least one itaconic acid derivative, and

[0344] (B) at least one amino acid of the general formula (1)

[0345] H2N-R 1 -C(=O)-R 2 (1)

[0346] in

[0347] R 1 Selected from at least monosubstituted C2-C 20 -alkanediyl and at least monosubstituted C3-C 20 -Cycloalkane

[0348] The group consisting of two radicals, wherein the substituent is NH2;

[0349] R 2 Selected from Cl, Br and OR 3 The group consisting of

[0350] R 3 Choose from H, C1-C 10 -alkyl, C3-C 10 -cycloalkyl and C2-C 15-alkenyl group.

[0351] In various embodiments, R 1 It is a straight-chain and saturated monosubstituted C3-C6 alkanediyl, especially C4-alkanediyl, C5-alkanediyl or C6-alkanediyl, preferably C5-alkanediyl, wherein the NH2 substituent is located on the most distal carbon atom. Preferably, the amino acid is D-lysine or L-lysine, more preferably L-lysine.

[0352] Preferred embodiments (e.g. with respect to component (A) and component (B)) have already been disclosed above with respect to the pyrrolidone-containing polymer (PP) and its use as a spray drying aid and in the process for producing RDP and apply analogously to the pyrrolidone-containing polymer (PP). Particularly preferred embodiments are mentioned below.

[0353] For example, based on the sum of the weight percentages of components (A) and (B), the reaction mixture (rM2) comprises component (A) in a range of 0.5 wt % to 70 wt % and component (B) in a range of 30 wt % to 99.5 wt %. In a preferred embodiment, based on the total weight of the reaction mixture (rM2), the reaction mixture (rM2) comprises component (A) in a range of 0.5 wt % to 70 wt % and component (B) in a range of 30 wt % to 99.5 wt %.

[0354] Based on the sum of the weight percentages of components (A) and (B), preferably based on the total weight of the reaction mixture (rM2), the reaction mixture (rM2) preferably contains component (A) in the range of 5 wt % to 70 wt % and component (B) in the range of 30 wt % to 95 wt %.

[0355] Based on the sum of the weight percentages of components (A) and (B), preferably based on the total weight of the reaction mixture (rM2), it is particularly preferred that the reaction mixture (rM2) contains component (A) in a range of 10% to 60% by weight and component (B) in a range of 40% to 90% by weight.

[0356] Unless otherwise stated, all weight percentages of components (A) and (B) and optionally of component (C) are based on the composition of the reaction mixture (rM2) before the start of polymerization of the reaction mixture (rM2).

[0357] The molar ratio of component (A) to component (B) in the reaction mixture (rM2) is, for example, in the range of 10:1 to 1:10.

[0358] Preferably, the molar ratio of component (A) to component (B) in the reaction mixture (rM2) is in the range of 6:1 to 1:5.

[0359] Most preferably, the molar ratio of component (A) to component (B) in the reaction mixture (rM2) is in the range of 3:1 to 1:2.

[0360] Therefore, most preferred are pyrrolidone-containing polymers (PP) wherein the molar ratio of component (A) to component (B) in the reaction mixture (rM2) is in the range from 3:1 to 1:2.

[0361] Furthermore, preference is given to pyrrolidone-containing polymers (PP) in which the molar ratio of component (A) to component (B) in the reaction mixture (rM2) is in the range from 3:1 to 1:10.

[0362] As described above for the weight percentages, this molar ratio also relates to the molar ratio of component (A) to component (B) before the start of polymerization, ie before components (A) and (B) have reacted with each other.

[0363] The reaction mixture (rM2) may further comprise component (C), ie at least one catalyst.

[0364] Suitable components (C) have been described above.

[0365] Preferably, the reaction mixture (rM2) further comprises component (C), ie at least one catalyst selected from the group consisting of phosphoric acid, alkali metal dihydrogenphosphates, alkali metal hypophosphites, alkali metal hydrogensulfates, tin octoate, titanium(IV) butoxide and bismuth-2,2-diphenylundecanoate.

[0366] Alkali metal hypophosphites are preferred as component (C), and suitable alkali metal hypophosphites are described herein above. Sodium hypophosphite is particularly preferred as component (C).

[0367] For example, based on the sum of the weight percentages of components (A), (B) and (C), preferably based on the total weight of the reaction mixture (rM2), the reaction mixture (rM2) contains component (C) in a range of 0.1 wt % to 5 wt %, preferably in a range of 0.1 wt % to 3 wt %, and particularly preferably in a range of 0.1 wt % to 2 wt %.

[0368] It will be appreciated by those skilled in the art that the weight percentages of components (A) and (B) and optional component (C) generally add up to 100 weight percent.

[0369] The polymerization of the reaction mixture (rM2) can be carried out in the presence of at least one solvent (S).

[0370] Suitable solvents (S) are known to the person skilled in the art and have been described above. Preferably, the at least one solvent (S) is water.

[0371] Component (A) is at least one itaconic acid derivative. Therefore, within the context of the present invention, "itaconic acid derivative" comprises itaconic acid as well as itaconic acid derivatives according to the ordinary meaning of itaconic acid derivatives. Therefore, suitable itaconic acid derivatives are known to those skilled in the art.

[0372] Suitable itaconic acid derivatives are therefore, for example, itaconic acid, itaconic anhydride, itaconic esters and itaconic acid halides.

[0373] Preferably, component (A) is selected from the group consisting of itaconic acid, itaconic anhydride, itaconic esters and itaconic acid halides.

[0374] Itaconic acid is also known as 2-methylenebutanedioic acid, 2-methylenesuccinic acid or 1-propylene-2,3-dicarboxylic acid. Itaconic acid has the CAS number 97-65-4.

[0375] Itaconic anhydride is also known as 2-methylenesuccinic anhydride or itaconic anhydride. Itaconic anhydride has the CAS number 2170-03-8.

[0376] Suitable itaconates are the reaction products of itaconic acid and alkyl alcohols. Preferred alkyl alcohols are methanol, ethanol, propanol and butanol. Preferred itaconates are dimethyl itaconate and diethyl itaconate.

[0377] Preferred itaconyl halides are itaconyl chloride and itaconyl bromide, with itaconyl chloride being particularly preferred.

[0378] Therefore, component (A) is preferably selected from the group consisting of itaconic acid, itaconic anhydride, dimethyl itaconate, diethyl itaconate and itaconic acid chloride. Itaconic acid is particularly preferred as component (A).

[0379] Component (B) is at least one amino acid of the general formula (1)

[0380] H2N-R 1 -C(=O)-R 2 (1)

[0381] in

[0382] R 1 Selected from at least monosubstituted C2-C 20 -alkanediyl and at least monosubstituted C3-C 20 -cycloalkanediyl group, wherein the substituent is NH2;

[0383] R 2 Selected from Cl, Br and OR 3 The group consisting of

[0384] R 3 Choose from H, C1-C 10-alkyl, C3-C 10 -cycloalkyl and C2-C 15 -alkenyl group.

[0385] Preferably,

[0386] R 1 Selected from at least monosubstituted C2-C 20 -alkanediyl group, wherein the substituent is NH2,

[0387] R 2 Selected from the group consisting of OH and Cl.

[0388] Particularly preferably,

[0389] R 1 Selected from C3-C 10 - the group consisting of alkanediyl, wherein the substituent is NH2, especially straight-chain and saturated C4-alkanediyl, C5-alkanediyl or C6-alkanediyl, preferably C5-alkanediyl, wherein the NH2 substituent is located on the most distal carbon atom;

[0390] R 2 It's OH.

[0391] In a preferred embodiment, component (B) is selected from the group consisting of L-lysine, D-lysine and a racemic mixture of L-lysine and D-lysine.

[0392] For example, as described above for R of the general formula (1) 1 The “C2-C 20 "C2-C-alkanediyl" in the context of the present invention means a hydrocarbon having 2 to 20 carbon atoms and two free valencies. It is thus a diradical having 2 to 20 carbon atoms. 20 "-alkanediyl" encompasses straight-chain and branched, saturated and unsaturated hydrocarbons having 2 to 20 carbon atoms and two free valences. Saturated hydrocarbons are preferred. C2-C 20 Examples of -alkanediyl include, but are not limited to, ethylene (ethane-1,2-diyl, dimethylene), propane-1,3-diyl (trimethylene), propylene (propane-1,2-diyl), butane-1,4-diyl (tetramethylene), and n-pentane-1,5-diyl. In some embodiments, straight chain moieties may be preferred. Corresponding observations also apply to "C3-C 10 -alkanediyl".

[0393] For example, as described above for R of the general formula (1) 1 The “C3-C 20"C3-Cycloalkanediyl" in the context of the present invention means a cyclic hydrocarbon having 3 to 20 carbon atoms and two free valencies. It is thus a diradical having 3 to 20 carbon atoms. 20 "Cycloalkanediyl" encompasses cyclic hydrocarbons as well as hydrocarbons having a cyclic fraction and a linear fraction, the linear fraction having 3 to 20 carbon atoms and two free valences. 20 Examples of -cycloalkanediyl include, but are not limited to, cyclopropanediyl, cyclobutanediyl, cyclopentanediyl, cyclohexanediyl, cycloheptanediyl, cyclooctanediyl, and cyclodecanediyl.

[0394] In the context of the present invention, as for example above for R of the general formula (1) 3 The “C1-C 10 "-alkyl" means a hydrocarbon group having 1 to 10 carbon atoms. The alkyl group may be linear or branched. Examples of such alkyl groups include, but are not limited to, methyl, ethyl, n-propyl, isopropyl, butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl and octyl.

[0395] In the context of the present invention, as for example above for R of the general formula (1) 3 The “C3-C 10 "C3-Cycloalkyl" means a cyclic hydrocarbon group having 3 to 10 carbon atoms. 10 "-Cycloalkyl" also encompasses hydrocarbons having a cyclic fraction and a linear fraction having 3 to 10 carbon atoms and one free valence. Examples of such cycloalkyl groups include, but are not limited to, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl and cyclodecyl.

[0396] In the context of the present invention, as for example above for R of the general formula (1) 3 The “C2-C 15 "-alkenyl" means an unsaturated hydrocarbon group having at least one C-C double bond and 2 to 15 carbon atoms. Such C2-C 15 Examples of -alkenyl groups include, but are not limited to, ethenyl, propenyl, butenyl, pentenyl, and hexenyl.

[0397] The pyrrolidone-containing polymer (PP) can be obtained by polymerization of the reaction mixture (rM2). For example, the polymerization of the reaction mixture (rM2) is carried out at a temperature in the range of 50° C. to 300° C., preferably in the range of 70° C. to 250° C. and particularly preferably in the range of 90° C. to 240° C.

[0398] The polymerization can be carried out as a one-step process or as a multistep process. These processes are known to the person skilled in the art and are described in more detail below with regard to the process for producing the pyrrolidone-containing polymer (PP).

[0399] During the polymerization, components (A) and (B) undergo a polycondensation reaction to form the pyrrolidone-containing polymer (PP).

[0400] Within the context of the present invention, "pyrrolidone-containing polymer (PP)" means that the polymer comprises pyrrolidone groups, typically and preferably as part of its main chain (and not as side groups). Therefore, within the context of the present invention, the pyrrolidone-containing polymer (PP) is also referred to as "pyrrolidone-containing polymer (PP)". Therefore, the terms "pyrrolidone-containing polymer (PP)" and "pyrrolidone-containing polymer (PP)" are used synonymously throughout the present invention and have the same meaning.

[0401] The pyrrolidone-containing polymer (PP) according to the invention comprises units derived from components (A) and (B).

[0402] Thus, the pyrrolidone-containing polymer (PP) may comprise units resulting from the reaction of component (A) with component (B).The pyrrolidone-containing polymer (PP) may also comprise units resulting from the reaction of two components (B).

[0403] The pyrrolidone-containing polymer (PP) may be linear or branched. In particular, the pyrrolidone-containing polymer (PP) may be branched if it comprises units resulting from the reaction of two components (B).

[0404] In a preferred embodiment, the pyrrolidone-containing polymer (PP) comprises at least one unit of the general formula (A)

[0405]

[0406] in

[0407] R 4 Selected from at least monosubstituted C2-C 20 Alkanediyl and C3-C 20 The group consisting of cycloalkanediyl, wherein at least one substituent is C(=O)R 2 ,in

[0408] R 2 Selected from Cl, Br and OR 3 The group consisting of

[0409] R 3 Choose from H, C1-C 10 Alkyl, C3-C 10 Cycloalkyl and C2-C 15 A group consisting of alkenyl.

[0410] R 4Preferably selected from at least monosubstituted C2-C 20 -alkanediyl, wherein at least one substituent is C(=O)R 2 ,in

[0411] R 2 Selected from the group consisting of OH and Cl.

[0412] R 4 Most preferably selected from the group consisting of monosubstituted C3-C 10 -alkanediyl, wherein the substituent is C(=O)OH. In such embodiments, R 4 It may be a linear or saturated monosubstituted C3-C6-alkanediyl group, in particular a C4-alkanediyl group, a C5-alkanediyl group or a C6-alkanediyl group, preferably a C5-alkanediyl group.

[0413] The weight average molecular weight (M w ) is, for example, in the range of 500 g / mol to 100,000 g / mol, preferably 1,000 g / mol to 50,000 g / mol, and particularly preferably 1,000 g / mol to 10,000 g / mol, determined by gel permeation chromatography (GPC) with 0.1% (w / w) trifluoroacetic acid, 0.1 M NaCl in distilled water as solvent.

[0414] The number average molecular weight (M n ) is preferably in the range of 500 g / mol to 20,000 g / mol, particularly preferably in the range of 500 g / mol to 10,000 g / mol, and most preferably in the range of 500 g / mol to 5,000 g / mol, determined by size exclusion chromatography (SEC) using as solvent: water / methanol (80 / 20)+0.01 mol / l phosphate buffer pH=7.4.

[0415] The polydispersity (PD) of the pyrrolidone-containing polymer (PP) is typically in the range of 1.1 to 5, preferably in the range of 1.1 to 4, and most preferably in the range of 1.1 to 3. The polydispersity (PD) is the weight average molecular weight (M) of the pyrrolidone-containing polymer (PP). w ) and number average molecular weight (M n ) between them.

[0416] The amino value of the pyrrolidone-containing polymer (PP) of the present invention is, for example, in the range of 20 mg KOH / g to 500 mg KOH / g, preferably in the range of 50 mg KOH / g to 450 mg KOH / g, and most preferably in the range of 75 mg KOH / g to 400 mg KOH / g, determined by titration. Suitable titrations are known to the skilled person and are described in further detail in the examples of the present invention.

[0417] As mentioned above, the present invention relates in an eighth aspect to a method for producing a pyrrolidone-containing polymer (PP), wherein the method comprises the polymerization of a reaction mixture (rM2), wherein the reaction mixture (rM2) comprises at least the following components:

[0418] (A) at least one itaconic acid derivative, and

[0419] (B) at least one amino acid of the general formula (1)

[0420] H2N-R 1 -C(=O)-R 2 (1)

[0421] in

[0422] R 1 Selected from at least monosubstituted C2-C 20 Alkanediyl and at least monosubstituted C3-C 20 The group consisting of cycloalkanediyl, wherein the substituent is NH2;

[0423] R 2 Selected from Cl, Br and OR 3 The group consisting of

[0424] R 3 Choose from H, C1-C 10 Alkyl, C3-C 10 Cycloalkyl and C2-C 15 A group consisting of alkenyl.

[0425] The preferred embodiments are the same as those disclosed above in relation to other aspects of the invention. Particularly preferred embodiments are disclosed in the following.

[0426] In a preferred embodiment, the reaction mixture (rM2) further comprises component (C), namely at least one catalyst selected from the group consisting of phosphoric acid, alkali metal dihydrogenphosphates, alkali metal hypophosphites, alkali metal hydrogensulfates, tin octoate, titanium(IV) butoxide and bismuth-2,2-diphenylundecanoate.

[0427] The polymerization of the reaction mixture (rM2) can be carried out by any method known to the person skilled in the art. Preferably, the polymerization of the reaction mixture (rM2) can be carried out in the presence of at least one solvent (S).

[0428] Suitable solvents (S) are known to the person skilled in the art and have been described above. Preferably, the at least one solvent (S) is water.

[0429] Preferably, the polymerization of the reaction mixture (rM2) comprises the following steps:

[0430] a) heating the reaction mixture (rM2) to a first temperature (T1) in the presence of at least one solvent (S) to obtain a prepolymerization mixture (pM2) comprising a pyrrolidone-containing prepolymer and at least one solvent (S),

[0431] b) removing at least one solvent (S) from the prepolymerization mixture (pM2) obtained in step a) to obtain a solvent-free prepolymerization mixture (spM2), the solvent-free prepolymerization mixture (spM2) comprising a pyrrolidone-containing prepolymer,

[0432] c) heating the solvent-free prepolymerization mixture (spM2) obtained in step b) to a second temperature (T2) higher than the first temperature (T1) to obtain a pyrrolidone-containing polymer (PP).

[0433] The heating of the reaction mixture (rM2) in step a) can be carried out by any method known to those skilled in the art. The reaction mixture (rM2) can be stirred during heating. Preferably, step a) is carried out under an inert gas. Suitable inert gases for step a) are known to those skilled in the art, and are, for example, nitrogen and / or argon.

[0434] For example, in step a), based on the sum of the weight percentages of the reaction mixture (rM2) and at least one solvent (S), 20 wt % to 100 wt % of the reaction mixture (rM2) is heated in the presence of at least one solvent (S). Preferably, in step a), based on the sum of the weight percentages of the reaction mixture (rM2) and at least one solvent (S), 20 wt % to 99 wt % of the reaction mixture (rM2) is heated in the presence of at least one solvent (S).

[0435] Therefore, in one embodiment of the present invention, no solvent (S) is present in step a). The polymerization of the reaction mixture (rM2) then comprises the following steps:

[0436] a1) heating the reaction mixture (rM2) to a first temperature (T1) to obtain a prepolymerization mixture (pM2) comprising a pyrrolidone-containing prepolymer,

[0437] c1) heating the prepolymer mixture (pM2) obtained in step a1) to a temperature above a first temperature

[0438] (T1) to a second temperature (T2) to obtain a pyrrolidone-containing polymer (PP).

[0439] The first temperature (T1) to which the reaction mixture (rM2) is heated in step a) and in step a1) is generally in the range of 50 to 150°C, preferably in the range of 90 to 120°C.

[0440] The reaction mixture (rM2) can then be maintained at the first temperature (T1). For example, the reaction mixture (rM2) can be maintained at the first temperature (T1) for 15 minutes to 24 hours, preferably 30 minutes to 15 hours.

[0441] At the first temperature (T1), the components contained in the reaction mixture (rM2), in particular components (A) and (B), react with each other to form oligomers containing pyrrolidone groups. This reaction is also referred to as prepolymerization of components (A) and (B).

[0442] In step a), a pyrrolidone-containing prepolymer is obtained.

[0443] In the context of the present invention, "pyrrolidone-containing prepolymer" means that the prepolymer contains pyrrolidone groups. Therefore, in the context of the present invention, the pyrrolidone-containing prepolymer is also referred to as "pyrrolidone-containing prepolymer". Therefore, the terms "pyrrolidone-containing prepolymer" and "pyrrolidone-containing prepolymer" are used synonymously throughout the present invention and have the same meaning.

[0444] At least one solvent (S) can be removed from the prepolymer mixture (pM2) in step b) by any method known to those skilled in the art. For example, at least one solvent (S) can be removed under reduced pressure and / or at a temperature higher than the first temperature (T1) and lower than the decomposition temperature of the pyrrolidone-containing prepolymer.

[0445] In step b), a solvent-free prepolymer mixture (spM2) is obtained. The solvent-free prepolymer mixture (spM2) generally contains less than 5% by weight, preferably less than 2% by weight, particularly preferably less than 1% by weight of at least one solvent (S), based on the total weight of the solvent-free prepolymer mixture (spM2).

[0446] The heating of the solvent-free prepolymer mixture (spM2) in step c) can be carried out by any method known to those skilled in the art. The solvent-free prepolymer mixture (spM2) can be stirred during heating. Preferably, step c) is carried out under an inert gas. Suitable inert gases are known to those skilled in the art. Suitable inert gases are, for example, nitrogen and / or argon.

[0447] Preferably, step c) is performed at a pressure in the range of 5 mbar to 50 bar, preferably in the range of 10 mbar to 5 bar, most preferably in the range of 10 mbar to 2 bar.

[0448] The second temperature (T2) to which the solvent-free prepolymerization mixture (spM2) is heated in step c) is higher than the first temperature (T1) to which the reaction mixture (rM2) is heated in step a). For example, the second temperature T2 is in the range of 100°C to 300°C, preferably in the range of 120°C to 250°C.

[0449] The solvent-free prepolymerization mixture (spM2) can then be maintained at a second temperature (T2). For example, the solvent-free prepolymerization mixture (spM2) can be maintained at the second temperature (T2) for 15 minutes to 10 hours, preferably 15 minutes to 5 hours.

[0450] During the heating in step c), the solvent-free prepolymerization mixture (spM2) polymerizes to obtain the pyrrolidone-containing polymer (PP).

[0451] For step c1), the embodiments and preferences described for step c) apply analogously.

[0452] After step c) or step c1), step d) may be performed. Step d) may, for example, be selected from the group comprising a hydrophobizing step, an alkoxylating step and a quaternizing step.

[0453] Therefore, these steps are known to those skilled in the art.

[0454] In the hydrophobization step, the pyrrolidone-containing polymer (PP) is reacted with a hydrophobic compound, so that a pyrrolidone-containing polymer (PP) which is less hydrophilic or even hydrophobic than before the reaction is obtained.

[0455] Suitable compounds which can react with the pyrrolidone-containing polymer (PP) in the hydrophobization step are, for example, selected from the group consisting of fatty acids, activated fatty acids, polyisobutylene succinic anhydride and caprolactone. Suitable activated fatty acids are, for example, fatty acid anhydrides, fatty acid esters or fatty amines. These compounds are known to those skilled in the art.

[0456] In the alkoxylation step, an epoxy compound is reacted with the pyrrolidone-containing polymer (PP). Epoxy compounds are also referred to as alkylene oxides. Suitable alkylene oxides are, for example, ethylene oxide, propylene oxide and / or butylene oxide.

[0457] In the quaternization step, the nitrogen atoms of the pyrrolidone-containing polymer (PP) are reacted with a quaternizing agent to obtain quaternary ammonium cations in the pyrrolidone-containing polymer (PP). Suitable quaternizing agents are known to those skilled in the art and are, for example, selected from the group consisting of alkyl halides and dialkyl sulfates. Suitable alkyl halides are, for example, methyl chloride, ethyl chloride, methyl bromide, ethyl bromide and / or benzyl chloride. Suitable dialkyl sulfates are, for example, selected from the group consisting of dimethyl sulfate and diethyl sulfate. Organic acids such as lactic acid are also suitable as quaternizing agents.

[0458] In a preferred embodiment, the process further comprises at least one step selected from the group consisting of a hydrophobizing step, an alkoxylating step and a quaternizing step.

[0459] Example

[0460] The present invention is further illustrated in detail by the following non-limiting examples.

[0461] Materials and methods

[0462] Itaconic acid was purchased from Sigma-Aldrich (>99% purity).

[0463] L-Lysine (using ADM, 50% aqueous solution, if not otherwise stated, in spray drying aid 15 from Sigma-Aldrich, purity >98%)

[0464] Sodium hypophosphite monohydrate (Sigma Aldrich, >99% purity) was used as component (C)

[0465] Number average molecular weight (Mn) and weight average molecular weight (Mw) :

[0466] Spray Drying Aids 1 to 9 :

[0467] The weight average molecular weight (Mw) was determined by gel permeation chromatography (GPC) using a 0.05 M aqueous ammonium formate / methanol mixture = 80:20 (volume parts) as the eluent.

[0468] The number average molecular weight (Mn) was determined by gel permeation chromatography (GPC) using a 0.05 M aqueous ammonium formate / methanol mixture = 80:20 (volume parts) as the eluent.

[0469] The molecular weight (mass average molar mass (Mw) and number average molar mass (Mn)) of the polymer was determined as follows: a sample was prepared for the determination of the molar mass by dissolving the copolymer solution in a GPC eluent so that the polymer concentration in the GPC eluent was 0.5 wt %. Afterwards, the solution was filtered through a syringe filter with a polyethersulfone membrane and a pore size of 0.45 μm. The injection volume of the filtrate was 50 μL-100 μL. The average molecular weight was determined on a Waters GPC instrument with a model name of Alliance 2690 with a UV detector (Waters 2487) and an RI detector (Waters 2410). The following settings and conditions were used:

[0470] Column: Shodex SB-G guard column and Shodex OHpak SB of SB-800HQ series

[0471] 804HQ and 802.5HQ (PHM gel, 8×300 mm, pH 4.0 to 7.5)

[0472] Eluent: 0.05M aqueous ammonium formate / methanol mixture = 80:20 (volume fractions)

[0473] Flow rate: 0.5mL / min

[0474] Temperature: 50℃.

[0475] Injection: 50μL to 100μL

[0476] Detection: RI and UV

[0477] Depending on the nature of the copolymers, their molecular weights were determined relative to poly(ethylene glycol) and poly(ethylene oxide) or polyacrylic acid standards from PSS Polymer Standards Service GmbH. The molecular weight distribution curve of the polyacrylic acid standards was determined by light scattering.

[0478] Spray drying aid 10 to 14 :

[0479] Measured via size exclusion chromatography under the following conditions:

[0480] Solvent: water / methanol (80 / 20) + 0.01 mol / l phosphate buffer pH = 7.4

[0481] Flow rate: 0.8ml / min

[0482] Injection volume: 20 μl

[0483] Column material: Hydroxylated polymethacrylate (TSKgel G3000PWXL)

[0484] Calibration: Polyvinylpyrrolidone standards with molar masses ranging from 3500 g / mol to 710 000 g / mol (from Polymer American Standards, USA)

[0485] Spray Drying Aids 15 and 16 :

[0486] Gel permeation chromatography (GPC) was performed using a conventional GPC apparatus equipped with columns PL HFIP Gel (styrene divinylbenzene copolymer) (7.5×300 mm) and PL HFIPGel (SVD) (7.5×300 mm) and a refractive index (RI) detector. The columns were maintained at a temperature of 35° C. and the samples were eluted with hexafluoroisopropanol containing 0.05% potassium trifluoroacetate at a flow rate of 1 ml / min. For each analysis, 50 μl of a 1.5 mg / ml solution were injected. GPC calibration was performed using PMMA standards (800 g / mol-1 820000 g / mol) from PSS-PolymerStandards Service GmbH (Germany) of the inventors.

[0487] Amino value :

[0488] The amino value (unit: mg KOH / g), also referred to as the amino value, is determined by titration. A potentiometric titrator (potentiograph) equipped with a Dosimat with a 10 ml interchangeable burette and a combined glass-Ag / AgCl-electrode, for example a titration processor 726 model with a Dosimat 685 (Metrohm) is used. In a 100 ml beaker, about 0.1 g to 1.0 g of sample (the exact mass is selected according to the expected amine value) is mixed with 50 ml of glacial acetic acid to obtain a solution. The solution is titrated with 0.1 N trifluoromethanesulfonic acid (standard solution in glacial acetic acid, c(CF3SO3H)=0.1 mol / l) until a point of inflection of about 600 mV potential is reached. A blank value is determined using a solvent.

[0489] Calculation of amine value:

[0490]

[0491] in

[0492] Amine value: fraction of total amines calculated in mg KOH / g

[0493] VP: Consumption of standard solution until the inflection point [ml]

[0494] VB: Consumption of standard solution in blank value titration [ml]

[0495] t: titer of standard solution

[0496] c: concentration of standard solution [= 0.1 mol / l]

[0497] E: Weight of sample taken out [g]

[0498] 56.1 is the molar mass of KOH [g / mol]

[0499] For the Examples and Comparative Examples, the following starting materials were used:

[0500] Spray Drying Aids :

[0501] Spray drying additives 1 :

[0502] In a reaction vessel (four-necked flask) equipped with a reflux condenser, agitator, a thermometer, a dropping funnel and nitrogen bubbling, a solution of 520.4 g of itaconic acid, 123.6 g of ethylenediamine and 500 mL of water was stirred and refluxed for one hour. Then, 208.5 g of 1,5-pentanediamine was added. Water was removed by a distillation apparatus at normal pressure and later by applying a vacuum. In parallel, the reaction mixture was slowly heated to 180°C. Under a vacuum of <2 mbar, the reaction was continued until the agitator showed a torque of 20 Ncm. The K value of the polymer obtained was 20.6, and the molecular weight M W is ~5020g / mol and M N It is ~2350g / mol.

[0503] Spray drying additive 2 :

[0504] In a manner similar to the synthesis procedure described for spray drying aid 1, 339.9 g of itaconic acid and 133.5 g of 1,5-pentanediamine were used to synthesize spray drying aid 2. Afterwards, 39.5 g of ethylenediamine and 67.1 g of 1,5-pentanediamine were added. The same treatment as described for spray drying aid 1 was then carried out. The K value of the polymer obtained was 18.6 and the molecular weight M W is ~4690g / mol and M N It is ~2190g / mol.

[0505] Spray drying additives 3 :

[0506] In a manner similar to the synthesis procedure described for spray drying aid 1, spray drying aid 3 was synthesized using 390.3 g of itaconic acid and 92.0 g of ethylenediamine. Thereafter, 46.0 g of ethylenediamine and 78.2 g of 1,5-pentanediamine were added. The same treatment as described for spray drying aid 1 was then carried out. The K value of the polymer obtained was 16.5, and the molecular weight M Wis ~4360g / mol and M N It is ~2010g / mol.

[0507] Spray drying additives 4 :

[0508] 526.32g of 50% aqueous solution of L-Lysine (1.8mol) was placed in a 2L four-necked flask equipped with a stirrer, a condenser column, a thermometer and a nitrogen inlet. 117.09g of itaconic acid (0.9mol) was added to the L-Lysine solution. The mixture was heated to boiling point and kept under reflux for 10 hours under stirring and an inert atmosphere (N2 flow). Then, the temperature of the external heat source was raised according to the following curve: at 150°C for 1 hour, at 160°C for 1 hour, at 170°C for 1 hour and at 180°C for 1 hour, while water was distilled off. The warm reaction melt was collected in an aluminum container. At room temperature, a solid material was obtained. The amino value of the polymer obtained was 308mg KOH / g. The molecular weight M of the polymer was 2.377 W / m3. W is ~2410g / mol and M N It is ~2175g / mol.

[0509] (Reference) Spray Drying Aid 5 :

[0510] Commercially available polyacrylamide (PAM; catalog number 22581) in water, manufactured by Polysciences Inc. The polymer has a solids content of 50 wt% and a molecular weight M of -10,000 g / mol. W .

[0511] (Reference) Spray Drying Aid 6 :

[0512] In a reaction vessel equipped with a reflux condenser, a stirrer, a thermometer, a dropping funnel and a nitrogen sparge, an initial charge of 280 g of water and 195 g of Na-2-acrylamido-2-methylpropanesulfonic acid (AMPS) was heated to 18° C. While stirring, 70 g of a 50% sodium hydroxide solution was added dropwise at 18° C. Subsequently, 68 g of acrylic acid, 2.8 g of 2,2'-azobis(2-methylpropionamidine) dihydrochloride (Wako V50) and 4 g of mercaptoethanol were metered over 10 minutes while stirring. The reaction solution was stirred at 70° C. to 80° C. for 1.5 hours and then cooled to room temperature. The resulting product was a solids content of 48.1% by weight, a pH of 0.8 and a molecular weight of M W It is a transparent polymer solution of about 8400 g / mol.

[0513] (Reference) Spray Drying Aid 7 :

[0514] In a reaction vessel equipped with a reflux condenser, a stirrer, a thermometer, a dropping funnel and a nitrogen sparge, an initial charge of 350 g of water and 313 g of Na-2-acrylamido-2-methylpropanesulfonic acid (AMPS) was heated to 18° C. While stirring, 112 g of a 50% sodium hydroxide solution was added dropwise at 18° C. Subsequently, 27 g of acrylic acid, 2.8 g of 2,2'-azobis(2-methylpropionamidine) dihydrochloride (Wako V50) and 6 g of mercaptoethanol were metered over 14 minutes while stirring. The reaction solution was stirred at 70° C. to 80° C. for 1.5 hours and then cooled to room temperature. The resulting product was a solids content of 48.5% by weight, a pH of 0.8 and a molecular weight of M W It is a transparent polymer solution of about 7400 g / mol.

[0515] (Reference) Spray drying aid 8: 4-88

[0516] Commercially available partially saponified polyvinyl alcohol (PVOH) is a solid 86.7 mol% to 88.7 mol% hydrolysis degree, 97.5% ± 2.5% non-volatile fraction (measured after drying for 3 hours at 105°C according to DIN 53189 / JIS K 6726), and has a viscosity of 3.5 mPa*s to 4.5 MPa*s as a 4% aqueous solution at 20°C (according to DIN 53015 / JIS K6726). This polymer is manufactured by Kuraray and is available under the trade name 4-88 obtained.

[0517] (Reference) Spray Drying Aid 9 :

[0518] A polyacid based on the monomers methacrylic acid and 2-methyl-2-propene-1-sulfonic acid. The polyacid has a molecular weight M of ∼1400 g / mol. W And synthesized as described in US2020 / 0207671 A1, page 10, paragraphs 0234 to 0235.

[0519] Spray drying aid 10 :

[0520] 380.10g of 50% aqueous solution (1.3mol) of L-Lysine is placed in a 2L four-necked flask equipped with a stirrer, a condensation column, a thermometer and a nitrogen inlet. 169.10g of itaconic acid (1.3mol) and 5.9g of sodium hypophosphite monohydrate are added to the L-Lysine solution. The mixture is heated to boiling point and kept under reflux for 10h (hours) under stirring and an inert atmosphere (N2 flow). Then the temperature of the external heat source is increased according to the following curve: 150°C for 3 hours, 160°C for 2 hours, and water is distilled off at the same time. The pressure is then reduced to 600 millibars, while the external heat source is increased to 180°C. The reaction is continued for about 1 hour under vacuum (600 millibars). The warm reaction melt is collected in an aluminum container. At room temperature (20°C), a solid material is obtained. The polymer obtained had an amino value of 122 mg KOH / g, a molecular weight Mn of -3290 g / mol, a Mw of -4350 g / mol, and a PD of -1.3.

[0521] Spray drying additives11 :

[0522] 380.10g of 50% aqueous solution of L-Lysine (1.3mol) was placed in a 2L four-necked flask equipped with a stirrer, a condensation column, a thermometer and a nitrogen inlet. 169.10g of itaconic acid (1.3mol) was added to the L-Lysine solution. The mixture was heated to boiling point and kept under reflux for 10 hours under stirring and an inert atmosphere (N2 flow). Then, the temperature of the external heat source was raised according to the following curve: 150°C for 1 hour, 160°C for 2 hours, and water was distilled off at the same time. The pressure was then reduced to 600 mbar, while the external heat source was raised to 180°C. The reaction was continued for about 20 minutes under vacuum (600 mbar). The warm reaction melt was collected in an aluminum container. At room temperature (20°C), a solid material was obtained. The amino value of the polymer obtained was 132mgKOH / g, the molecular weight Mn was ~3020g / mol, the Mw was ~3840g / mol, and the PD was ~1.3.

[0523] Spray drying aid 12 :

[0524] 526.32g of 50% aqueous solution of L-Lysine (1.8mol) was placed in a 2L four-necked flask equipped with a stirrer, a condensing column, a thermometer and a nitrogen inlet. 117.09g of itaconic acid (0.9mol) was added to the L-Lysine solution. The mixture was heated to boiling point and kept under reflux for 10 hours under stirring and an inert atmosphere (N2 flow). Then, the temperature of the external heat source was raised according to the following curve: at 150°C for 1 hour, at 160°C for 1 hour, at 170°C for 1 hour and at 180°C for 1 hour, while distilling out water. The warm reaction melt was collected in an aluminum container. At room temperature (20°C), a solid material was obtained. The amino value of the polymer obtained was 373mg KOH / g, the molecular weight Mn was ~2020g / mol, the Mw was ~2260g / mol, and the PD was ~1.1.

[0525] Spray drying aid 13 :

[0526] 380.10g of 50% aqueous solution (1.3mol) of L-Lysine is placed in a 2L four-necked flask equipped with agitator, condenser column, thermometer and nitrogen inlet. 169.10g of itaconic acid (1.3mol) is added to the L-Lysine solution. The mixture is heated to boiling point and kept under reflux for 10 hours under stirring and inert atmosphere (N2 flow). Then, the temperature of the external heat source is raised according to the following curve: at 150°C for 1 hour, at 160°C for 4 hours, at 170°C for 1 hour, while distilling out water. The pressure is then reduced to 430 millibars, while the external heat source is raised to 180°C. Continue the reaction for about 40 minutes under vacuum (430 millibars). The warm reaction melt is collected in an aluminum container. At room temperature (20°C), a solid material is obtained. The polymer obtained had an amino value of 101 mg KOH / g, a molecular weight Mn of ˜3820 g / mol, a Mw of ˜5520 g / mol, and a PD of ˜1.4.

[0527] Spray drying additive 14 :

[0528] 380.10g of 50% aqueous solution (1.3mol) of L-Lysine is placed in a 2L four-necked flask equipped with a stirrer, a condensing column, a thermometer and a nitrogen inlet. 169.10g of itaconic acid (1.3mol) and 5.49g of sodium hypophosphite are added to the L-Lysine solution. The mixture is heated to boiling point and kept under reflux for 10 hours under stirring and an inert atmosphere (N2 flow). Then, the temperature of the external heat source is raised according to the following curve: 150°C for 1 hour, 160°C for 4 hours, 170°C for 30 minutes, while distilling out water. The pressure is then reduced to 430 millibars, while the external heat source is raised to 180°C. Continue the reaction for about one hour under vacuum (430 millibars). The warm reaction melt is collected in an aluminum container. At room temperature (20°C), a solid material is obtained. The polymer obtained had an amino value of 75 mg KOH / g, a molecular weight Mn of -4740 g / mol, a Mw of -8060 g / mol, and a PD of -1.7.

[0529] Spray drying aid 15 :

[0530] 52.04 g of itaconic acid, 58.48 g of L-lysine and 50 g of water were placed in a 500 mL four-necked flask equipped with a stirrer, a condensation column, a thermometer and a nitrogen inlet. The mixture was heated to 130° C. and water was distilled off within 40 minutes. The temperature was then raised to 160° C. and condensed for a further 15 minutes. The molecular weight Mn of the polymer obtained was ˜904 g / mol, Mw was ˜1190 g / mol, and PD was ˜1.31.

[0531] Spray drying additive 16 :

[0532] 52.04 g of itaconic acid, 40.8 g of 1,5-pentamethylenediamine and 50 g of water were placed in a 500 mL four-necked flask equipped with a stirrer, a condensation column, a thermometer and a nitrogen inlet. The mixture was heated to 130° C. and water was distilled off within 40 minutes. The temperature was then raised to 160° C. and condensed for a further 15 minutes. The molecular weight Mn of the polymer obtained was ˜1030 g / mol, Mw was ˜1480 g / mol, and PD was ˜1.43.

[0533] Aqueous dispersion

[0534] Dispersion 1 :

[0535] The dispersion was synthesized according to styrene-acrylate as described in US 2020 / 0207671 A1: Dispersion 1 on page 9. The polymer obtained had a solids content of 55% by weight, a glass transition temperature of −15° C. and a particle size of about 600 nm.

[0536] Dispersion 2 :

[0537] This dispersion is based on the same composition as Dispersion 1 and additionally contains 3 parts per hundred monomer (pphm) of M W The obtained polymer has a solid content of 54.6% by weight, a glass transition temperature of -15°C, and a particle size of about 730 nm.

[0538] Dispersion 3 :

[0539] The dispersion was synthesized according to a styrene-acrylate dispersion prepared by emulsion polymerization as described in WO 2013 / 117465 A1: Example "Polymeric Dispersion D" on pages 19-20. The dispersion had a solids content of 57% by weight, a glass transition temperature of -13°C and a particle size of 230 nm.

[0540] Dispersion 4 :

[0541] The dispersion is based on styrene-acrylate. The solids content of the polymer is 60% by weight, the glass transition temperature is -8°C to -10°C, and the particle size is about 550nm. The dispersion contains 68.5pphm n-butyl acrylate, 28.5pphm styrene and 3pphm acrylic acid. The dispersion is stabilized by 2 wt% emulsifier (fatty alcohol (C12-C14) ether sulfate with a degree of ethoxylation of ~30 EO units).

[0542] Dispersion 5 :

[0543] The solid content of the aqueous styrene-butadiene latex dispersion was 51 wt%, the glass transition temperature was 18°C, and the pH was ~8. The average particle size of the polymer particles as measured by dynamic light scattering (D50 value) was 185 nm, and the dispersion was stabilized by an emulsifier. The dispersion contained 66.0 pphm styrene, 32.0 pphm butadiene, and 2.1 pphm acrylonitrile.

[0544] Dispersion 6 :

[0545] Aqueous dispersion commercially available from Wacker 550ED. The dispersion is based on a copolymer of vinyl acetate and ethylene and is stabilized by polyvinyl alcohol as a protective colloid. The solids content of the dispersion is 53% by weight. The minimum film forming temperature (MFFT) of the polymer is ~0°C and the primary particle size is 900 nm.

[0546] Spray drying of dispersions

[0547] A) Preparation of Spray Drying Feed :

[0548] To prepare the dispersion to be spray dried, the selected aqueous polymer dispersion (as described above) and the selected spray drying aid (selected from spray drying aids No. 1 to No. 9 as described above) are mixed while stirring. The amount of spray drying aid used is shown in Table 1.

[0549] The concentration of the dispersion to be dried was adjusted using additional water to 44% by weight, relative to the solids content in the spray feed.

[0550] B) Spray Drying of Dispersions :

[0551] Spray drying was carried out by a commercially available laboratory-scale spray dryer (Niro atomizer from Niro) using nitrogen as drying gas. The aqueous dispersion to be dried was sprayed through a two-fluid nozzle. The inlet temperature of the drying gas was 130° C. to 140° C. Its outlet temperature was 60° C. to 70° C. The first antiblocking agent (1% by weight of hydrophobic silica powder based on the total amount of all components of the final product) was fed into the drying chamber through a further nozzle.

[0552] After the powder obtained is taken out from the spray dryer, it is mixed with 5-11 wt% (based on the total amount of all components of the final product) of a second antiblocking agent selected from commercially available antiblocking agents, namely talc.

[0553] Determination of the redispersibility of RDP :

[0554] Compositions consisting of dispersions containing the spray drying aids (SDAs) specified in Table 1 were used to produce films and their redispersion was tested. To this end, liquid dispersions (5 g solid) in 10 mL-15 mL water were mixed with the described amounts of the respective SDA and dried at room temperature for two days. Approximately 0.5 g of film was placed in 10 mL of distilled water while stirring (200 rpm) at room temperature. Upon rapid redispersion within a few minutes, it was found that these dispersions also had excellent spray drying capabilities and redispersible powders (RDPs) were obtained.

[0555] The redispersion assessment is as follows:

[0556] Complete redispersion within a few minutes: Very good

[0557] Almost complete redispersion within a few minutes: Good

[0558] Incomplete redispersion (partial film still evident): Moderate

[0559] Most of the film is insoluble or not redispersed: Poor

[0560] Table 1. Redispersibility of different combinations of dispersions and SDA as films and as RDP

[0561]

[0562]

[0563] *sc=solid content

[0564] **nd = not determined

[0565] Application Testing

[0566] The influence of redispersible powders on wet scrub resistance in coating formulations was investigated according to EN 13300. Therefore, a dry formulation was produced according to Table 2 and mixed with 365.00 parts by weight of deionized water.

[0567] Table 2: Coating formulation (dry)

[0568] Function / Components Weight <![CDATA[Basic thickener, HEC, M W 20000]]> 4.00 Dispersant (sodium salt of carboxylic acid copolymer in water; Dispex CX 4320) 3.00 Defoaming agent (modified polysiloxane) 4.00 Rutile; Titanium dioxide 60.00 Filler, fine aluminum silicate 20.00 Filler, precipitated calcium carbonate PCC 50.00 Flaky filler, talc 90.00 Filler, calcite 2μm 80.00 Filler, calcite 5μm 230.00 Dispersion powder 94.00(latex content)

[0569] If the dispersant has been co-spray dried with the dispersion, the dispersant has been removed from the formulation.

[0570] Several combinations were investigated for wet scrub resistance according to EN 13300. The lower the abrasion after 200 cycles, the better the coating formulation. The aqueous dispersion used for RDP shows the lowest abrasion, since there is no additional water-soluble polymer (SDA) that has no function for the coating system.

[0571] Table 3: Wet Scrub Resistance of Formulations Containing RDP .

[0572] Example combination Dispersion SDA Scrub [μm]*** Test 1 1 1 1 29 Test 2 2 1 2 45 Test 3 3 1 3 46 Reference Test 4 24 1 9 71

[0573] ***After 200 cycles

[0574] In the case of polyacid-based SDAs (spray drying aids 9), the resulting RDP is acidic and must be neutralized in the coating, as described in DE 19601699 A1. Neutralization is also required for construction material formulations. In addition, the wet scrub resistance is poor compared to the polymers of the invention. If the polycarboxylic acid is neutralized before spray drying the dispersion, the resulting dispersion powder is poorly redispersible, as described in WO 2018 / 224519.

[0575] Biodegradability according to OECD 301F

[0576] Spray drying additives 4 :

[0577] According to OECD 301F, the test polymer (Spray Drying Aid 4) was incubated with wastewater treatment sludge. A manometric respirometer ( The bottle head) tracks the amount of oxygen consumed by the microorganisms during biodegradation. Based on the oxygen uptake, the extent of biodegradation can be calculated:

[0578] Example 3: 55%-60% after 28 days ( Figure 1 )

[0579] Spray drying aid 12 :

[0580] According to OECD 301F, the test polymer (Spray Drying Aid 12) was incubated with wastewater treatment sludge. A manometric respirometer ( The bottle head) tracks the amount of oxygen consumed by the microorganisms during biodegradation. Based on the oxygen uptake, the extent of biodegradation can be calculated:

[0581] Spray drying aid 12: 55%-60% after 28 days

[0582] Biodegradability according to OECD 301B

[0583] Spray drying aid 15 vs. spray drying aid 16 :

[0584] According to OECD 301B, the test polymer (Spray Drying Aid 15) was incubated with wastewater treatment sludge. The amount of CO2 produced during biodegradation was followed. Based on the CO2 release, the degree of biodegradation can be calculated.

[0585] Spray drying aid 15: 30%-40% after 28 days

[0586] Spray drying aid 16: <10% after 28 days.

Claims

1. A pyrrolidone-containing polymer (PP), the pyrrolidone-containing polymer (PP) comprising at least one (monomer) unit of the general formula (I) to (III) wherein R is independently hydrogen, C1-C4-alkyl, or two groups R are linked to each other to form a six-membered ring; X is -O- or -NR; A is independently selected from C1-C 20 -alkanediyl, C3-C 20 -cycloalkanediyl and C6-C 20 - a group consisting of an arylene group, Wherein the C1-C 20 -alkanediyl is optionally interrupted by one or more non-adjacent oxygen atoms, sulfur atoms or functional groups -NR-, -CO-, -CO-O-, -CO-NR-, -SO- or -SO2-, in which the nitrogen atom is optionally protonated or quaternized, Wherein the C1-C 20 -alkanediyl and the C3-C 20 -cycloalkanediyl optionally carries at least one selected from C(=O)R 2 and SO3H, where R 2 Selected from Cl, Br and OR 3 The group consisting of R 3 Choose from H, C1-C 10 -alkyl, C3-C 10 -cycloalkyl and C2-C 15 -alkenyl group, Wherein the C6-C 20 -arylene is optionally inserted with oxygen, sulfur, -NR-, -SO- or -SO2- and is optionally substituted with -COOH or -SO3H or a mixture of these groups; Z is a group of formula (IV) Where B is C1-C 20 -alkanediyl, C6-C 20 -cycloalkanediyl or a mixture of such groups, wherein the C1-C 20 -alkanediyl optionally interrupted by one or more non-adjacent oxygen atoms, sulfur atoms or functional groups -NR-, -CO-, -CO-O-, -CO-NR-, -SO- or -SO2-, and optionally carrying an additional functional group -COOH or -SO3H, in which the nitrogen atom is optionally protonated or quaternized Or Z is a mixture of a group of formula (IV) and a group A; Used as a spray drying aid for aqueous polymer dispersions.

2. The pyrrolidone-containing polymer (PP) according to claim 1, wherein the pyrrolidone-containing polymer (PP) comprises at least one unit of the general formula (I) to (II) wherein R is independently hydrogen or C1-C2-alkyl; X is -NR; A is independently selected from C1-C 20 -alkanediyl group, the C1-C 20 -alkanediyl optionally carries at least one selected from C(=O)R 2 and SO3H, where R 2 Selected from Cl, Br and OR 3 The group consisting of R 3 Choose from H, C1-C 10 -alkyl, C3-C 10 -cycloalkyl and C2-C 15 A group consisting of alkenyl groups; Z is a group of formula (IV) Where B is C1-C 20 -alkylene, the C1-C 20 The -alkylene radical optionally carries an additional functional group -COOH or -SO3H, or Z is a mixture of a radical of the formula (IV) and a radical A.

3. The pyrrolidone-containing polymer (PP) according to claim 1 or 2, wherein (1) A is C1-alkanediyl, C2-alkanediyl, C3-alkanediyl, C4-alkanediyl, C5-alkanediyl or C6-alkanediyl, preferably C5-alkanediyl, wherein the alkanediyl is preferably linear and saturated; or (2) B is C1-alkanediyl, C2-alkanediyl, C3-alkanediyl, C4-alkanediyl, C5-alkanediyl or C6-alkanediyl, preferably C5-alkanediyl, wherein the alkanediyl is preferably linear and saturated.

4. The pyrrolidone-containing polymer (PP) according to claim 3 (1), wherein the alkanediyl group optionally carries a functional C(═O)R 2 A group wherein the R 2 The group is preferably OR 3 , where R 3 Preferably H, or a pyrrolidone-containing polymer (PP) according to claim 3(2), wherein the alkanediyl group optionally carries a functional COOH group on the terminal carbon atom.

5. The pyrrolidone-containing polymer (PP) according to any one of claims 1 to 4, wherein the pyrrolidone-containing polymer (PP) is obtainable by polymerization of a reaction mixture (rM1), wherein the reaction mixture (rM1) comprises at least the following components: (A) at least one itaconic acid derivative, preferably wherein component (A) is selected from the group consisting of itaconic acid, itaconic anhydride, itaconic esters and itaconic acid halides, and (B) at least one diamine, preferably wherein the diamine is selected from the group consisting of ethylenediamine, 1,3-diaminopropane, 1,4-diaminobutane, 1,5-pentanediamine, 1,6-diaminohexane, 1,7-diaminoheptane, 1,8-diaminooctane and 1,9-diaminononane, more preferably from ethylenediamine and 1,5-pentanediamine.

6. The pyrrolidone-containing polymer (PP) according to claim 5, wherein the reaction mixture (rM1) comprises at least two diamines, preferably selected from the group consisting of ethylenediamine, 1,3-diaminopropane, 1,4-diaminobutane, 1,5-pentanediamine, 1,6-diaminohexane and 1,7-diaminoheptane, and in particular wherein the reaction mixture (rM1) comprises ethylenediamine and 1,5-pentanediamine.

7. The pyrrolidone-containing polymer (PP) according to claim 5 or 6, wherein the at least one itaconic acid derivative and the at least one diamine, preferably the sum of the at least two diamines, are present in the reaction mixture (rM1) in a molar ratio of 3:1 to 1:3, preferably 2:1 to 1:2, in particular 1.5:1 to 1:1.

5.

8. The pyrrolidone-containing polymer (PP) according to any one of claims 1 to 4, wherein the pyrrolidone-containing polymer (PP) is obtainable by polymerization of a reaction mixture (rM2), wherein the reaction mixture (rM2) comprises at least the following components: (A) at least one itaconic acid derivative, preferably wherein component (A) is selected from the group consisting of itaconic acid, itaconic anhydride, itaconic esters and itaconic acid halides, and (B) at least one amino acid of the general formula (1) H2N-R 1 -C(=O)-R 2 (1) in R 1 Selected from at least monosubstituted C2-C 20 Alkanediyl and at least monosubstituted C3-C 20 The group consisting of cycloalkanediyl, wherein the substituent is NH2; R 2 Selected from Cl, Br and OR 3 The group consisting of R 3 Choose from H, C1-C 10 Alkyl, C3-C 10 Cycloalkyl and C2-C 15 The group consisting of alkenyl groups, preferably wherein component (B) is selected from the group consisting of L-lysine, D-lysine and a racemic mixture of L-lysine and D-lysine.

9. The pyrrolidone-containing polymer (PP) according to claim 8, wherein the at least one itaconic acid derivative and the at least one amino acid of the general formula (1) are present in the reaction mixture (rM2) in a molar ratio of 10:1 to 1:10, preferably 5:1 to 1:5, in particular 4:1 to 1:2 or 3:1 to 1:

5. 10 . Use of a pyrrolidone-containing polymer (PP) according to claim 1 as a spray-drying aid for aqueous polymer dispersions.

11. The use according to claim 10, wherein the aqueous polymer dispersion comprises a (co)polymer selected from the group consisting of acrylate polymers, acrylic acid-styrene copolymers, copolymers based on styrene-butadiene, vinyl acetate polymers and ethylene-vinyl acetate copolymers, preferably a (co)polymer selected from the group consisting of acrylic acid-styrene copolymers, copolymers based on styrene-butadiene and ethylene-vinyl acetate copolymers, more preferably an acrylic acid-styrene copolymer.

12. The use according to claim 11, wherein the (co)polymer of the aqueous polymer dispersion has a Tg of -60°C to 35°C, preferably -50°C to 25°C, more preferably -30°C to 10°C, the Tg being calculated using the Fox equation, and / or The average particle size (D50 value) of the polymer particles as measured by dynamic light scattering is from 50 nm to 1000 nm, preferably from 100 nm to 900 nm, more preferably from 150 nm to 750 nm.

13. A method for producing a redispersible dispersion powder (RDP), the method comprising the steps of: i) a pyrrolidone-containing polymer (PP) comprising at least one unit of the general formula (I) to (III) wherein R is independently hydrogen, C1-C4-alkyl, or two groups R are linked to each other to form a six-membered ring; X is -O- or -NR; A is independently selected from C1-C 20 -alkanediyl, C3-C 20 -cycloalkanediyl and C6-C 20 - a group consisting of an arylene group, Wherein the C1-C 20 -alkanediyl is optionally interrupted by one or more non-adjacent oxygen atoms, sulfur atoms or functional groups -NR-, -CO-, -CO-O-, -CO-NR-, -SO- or -SO2-, in which the nitrogen atom is optionally protonated or quaternized, Wherein the C1-C 20 -alkanediyl and the C3-C 20 -cycloalkanediyl optionally carries at least one selected from C(=O)R 2 and SO3H, where R 2 Selected from Cl, Br and OR 3 The group consisting of R 3 Choose from H, C1-C 10 Alkyl, C3-C 10 Cycloalkyl and C2-C 15 The group consisting of alkenyl groups, Wherein the C6-C 20 -arylene is optionally inserted with oxygen, sulfur, -NR-, -SO- or -SO2- and is optionally substituted with -COOH or -SO3H or a mixture of these groups; Z is a group of formula (IV) Where B is C1-C 20 -alkanediyl, C6-C 20 -cycloalkanediyl or a mixture of such groups, wherein the C1-C 20 -alkanediyl optionally interrupted by one or more non-adjacent oxygen atoms, sulfur atoms or functional groups -NR-, -CO-, -CO-O-, -CO-NR-, -SO- or -SO2-, and optionally carrying an additional functional group -COOH or -SO3H, in which the nitrogen atom is optionally protonated or quaternized Or Z is a mixture of a group of formula (IV) and a group A mixing with an aqueous polymer dispersion, the aqueous polymer dispersion preferably comprising a (co)polymer selected from the group consisting of acrylate polymers, acrylic acid-styrene copolymers, styrene-butadiene based copolymers, vinyl acetate polymers and ethylene-vinyl acetate copolymers; ii) spray drying the mixture obtained in step i).

14. The process according to claim 13, wherein in step i), the pyrrolidone-containing polymer (PP) is mixed with the aqueous polymer dispersion in an amount of 4 to 20% by weight, preferably 5 to 15% by weight, in particular 6 to 12% by weight, based on the solids content of the aqueous polymer dispersion.

15. A redispersible dispersion powder (RDP) obtained by the method according to claim 13 or 14.

16. A redispersible dispersion powder (RDP), comprising a (co)polymer and a pyrrolidone-containing polymer (PP), wherein the (co)polymer is selected from the group consisting of acrylate polymers, acrylic acid-styrene copolymers, styrene-butadiene-based copolymers, vinyl acetate polymers and ethylene-vinyl acetate copolymers, and the pyrrolidone-containing polymer (PP) comprises at least one unit of the general formula (I) to (III) wherein R is independently hydrogen, C1-C4-alkyl, or two groups R are linked to each other to form a six-membered ring; X is -O- or -NR; A is independently selected from C1-C 20 -alkanediyl, C3-C 20 -cycloalkanediyl and C6-C 20 - a group consisting of an arylene group, Wherein the C1-C 20 -alkanediyl is optionally interrupted by one or more non-adjacent oxygen atoms, sulfur atoms or functional groups -NR-, -CO-, -CO-O-, -CO-NR-, -SO- or -SO2-, in which the nitrogen atom is optionally protonated or quaternized, Wherein the C1-C 20 -alkanediyl and the C3-C 20 -cycloalkanediyl optionally carries at least one selected from C(=O)R 2 and SO3H, where R 2 Selected from Cl, Br and OR 3 The group consisting of R 3 Choose from H, C1-C 10 Alkyl, C3-C 10 Cycloalkyl and C2-C 15 The group consisting of alkenyl groups, Wherein the C6-C 20 -arylene is optionally inserted with oxygen, sulfur, -NR-, -SO- or -SO2- and is optionally substituted with -COOH or -SO3H or a mixture of these groups; Z is a group of formula (IV) Where B is C1-C 20 -alkanediyl, C6-C 20 -cycloalkanediyl or a mixture of such groups, wherein the C1-C 20 -alkanediyl optionally interrupted by one or more non-adjacent oxygen atoms, sulfur atoms or functional groups -NR-, -CO-, -CO-O-, -CO-NR-, -SO- or -SO2-, and optionally carrying an additional functional group -COOH or -SO3H, in which the nitrogen atom is optionally protonated or quaternized Alternatively, Z is a mixture of a group of formula (IV) and a group A.

17. A method of making a powder paint or coating, the method comprising blending a redispersible dispersion powder (RDP) according to claim 15 or 16 with a pigment.

18. A method of making a construction material composition, the method comprising blending the redispersible dispersion powder (RDP) according to claim 15 or 16 with cement.

19. A pyrrolidone-containing polymer (PP), which is obtainable by polymerization of a reaction mixture (rM2), wherein the reaction mixture (rM2) comprises at least the following components: (A) at least one itaconic acid derivative, and (B) at least one amino acid of the general formula (1) H2N-R 1 -C(=O)-R 2 (1) in R 1 Selected from at least monosubstituted C2-C 20 -alkanediyl and at least monosubstituted C3-C 20 - the group consisting of cycloalkanediyl, wherein the substituent is NH2; R 2 Selected from Cl, Br and OR 3 The group consisting of R 3 Choose from H, C1-C 10 -alkyl, C3-C 10 -cycloalkyl and C2-C 15 -alkenyl group.

20. The pyrrolidone-containing polymer (PP) according to claim 19, wherein component (A) is selected from the group consisting of itaconic acid, itaconic anhydride, itaconic esters and itaconic acid halides.

21. The pyrrolidone-containing polymer (PP) according to claim 19 or 20, wherein component (B) is selected from the group consisting of L-lysine, D-lysine and a racemic mixture of L-lysine and D-lysine.

22. The pyrrolidone-containing polymer (PP) according to any one of claims 19 to 21, wherein the pyrrolidone-containing polymer (PP) comprises at least one unit of the general formula (A) in R 4 Selected from at least monosubstituted C2-C 20 Alkanediyl and C3-C 20 The group consisting of cycloalkanediyl, wherein at least one substituent is C(=O)R 2 ,in R 2 Selected from Cl, Br and OR 3 The group consisting of R 3 Choose from H, C1-C 10 Alkyl, C3-C 10 Cycloalkyl and C2-C 15 A group consisting of alkenyl.

23. The pyrrolidone-containing polymer (PP) according to any one of claims 19 to 22, wherein the molar ratio of component (A) to component (B) in the reaction mixture (rM2) is in the range of 3:1 to 1:

10.

24. The pyrrolidone-containing polymer (PP) according to any one of claims 19 to 23, wherein the reaction mixture (rM2) comprises in the range of 0.5 wt.-% to 70 wt.-% of component (A) and in the range of 30 wt.-% to 99.5 wt.-% of component (B), based on the total weight of the reaction mixture (rM2).

25. The pyrrolidone-containing polymer (PP) according to any one of claims 19 to 24, wherein the reaction mixture (rM2) further comprises component (C), i.e. at least one catalyst selected from the group consisting of phosphoric acid, alkali metal dihydrogen phosphates, alkali metal hypophosphites, alkali metal hydrogen sulfates, tin octoate, titanium (IV) butoxide and bismuth 2,2-diphenyl undecanoate.

26. A method for producing a pyrrolidone-containing polymer (PP), wherein the method comprises the polymerization of a reaction mixture (rM2), wherein the reaction mixture (rM2) comprises at least the following components: (A) at least one itaconic acid derivative, and (B) at least one amino acid of the general formula (1) H2N-R 1 -C(=O)-R 2 (1) in R 1 Selected from at least monosubstituted C2-C 20 Alkanediyl and at least monosubstituted C3-C 20 The group consisting of cycloalkanediyl, wherein the substituent is NH2, preferably a linear and saturated monosubstituted C3-C6 alkanediyl, more preferably C4, C5 or C6, most preferably C5-alkanediyl, wherein the NH2 substituent is optionally located on the most distal carbon atom; R 2 Selected from Cl, Br and OR 3 The group consisting of R 3 Choose from H, C1-C 10 Alkyl, C3-C 10 Cycloalkyl and C2-C 15 A group consisting of alkenyl.

27. The method according to claim 26, wherein the reaction mixture (rM2) further comprises component (C), namely at least one catalyst selected from the group consisting of phosphoric acid, alkali metal dihydrogen phosphates, alkali metal hypophosphites, alkali metal hydrogen sulfates, tin octoate, titanium (IV) butoxide and bismuth 2,2-diphenyl undecanoate.

28. The method according to claim 26 or 27, wherein the polymerization of the reaction mixture (rM2) comprises the following steps: a) heating the reaction mixture (rM2) to a first temperature (T1) in the presence of at least one solvent (S) to obtain a prepolymerization mixture (pM2) comprising a pyrrolidone-containing prepolymer and the at least one solvent (S), b) removing said at least one solvent (S) from said prepolymerization mixture (pM2) obtained in step a) to obtain a solvent-free prepolymerization mixture (spM2), said solvent-free prepolymerization mixture (spM2) comprising said pyrrolidone-containing prepolymer, c) heating the solvent-free prepolymerization mixture (spM2) obtained in step b) to a second temperature (T2) higher than the first temperature (T1) to obtain the pyrrolidone-containing polymer (PP).

29. The method according to any one of claims 26 to 28, wherein the method further comprises at least one step selected from the group consisting of a hydrophobizing step, an alkoxylating step and a quaternizing step.

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