EP2414413A1

EP2414413A1 - Polyfunctional (meth)acrylic polymer, coating composition, process for producing a coating and coated article

Info

Publication number: EP2414413A1
Application number: EP10705894A
Authority: EP
Inventors: Bardo Schmitt; Wolfgang Klesse; Martina Ebert; Thorben SCHÜTZ; Mario Gomez Andreu
Original assignee: Evonik Roehm GmbH
Current assignee: Roehm GmbH Darmstadt
Priority date: 2009-03-30
Filing date: 2010-03-03
Publication date: 2012-02-08
Also published as: RU2011143584A; WO2010112290A1; US20120016071A1; JP5044726B2; DE102009001964A1; TW201105686A; KR20120027128A; CN102356102A; JP2012522080A

Abstract

The present invention relates to a (meth)acrylate polymer for production of a coating composition, wherein the (meth)acrylate polymer contains 0.5 to 20% by weight of units derived from (meth)acrylic monomers, which have at least one double bond in the alkyl radical and 8 to 40 carbon atoms, 0.1 to 60% by weight of units derived from monomers containing hydroxyl groups, said monomers having up to 9 carbon atoms, 0.1 to 95% by weight of units derived from (meth)acrylate having 1 to 12 carbon atoms in the alkyl radical, and 0.1 to 60% by weight of units derived from styrene monomers, based in each case on the weight of the (meth)acrylate polymer, and the (meth)acrylate polymer has a weight-average molecular weight in the range from 2000 to 60 000 g/mol. The present invention further relates to a coating composition and to a process for producing a coating. The present invention further relates to a coated article which comprises a coating obtainable by the process.

Description

Multifunctional (meth) acrylic polymer, coating composition, process for producing a coating and coated article

The present invention relates to a multifunctional (meth) acrylic polymer and a coating composition. In addition, the present invention is directed to a process for producing a coating carried out using this coating composition and a coated article obtainable by the present process.

Coating agents, in particular paints, have been produced synthetically for a long time. An important group of these agents is based on aqueous dispersions which often comprise (meth) acrylate polymers. For example, the document DE-A-41 05 134 describes aqueous dispersions which contain alkyl methacrylates as binders. Furthermore, such lacquers are known from US Pat. No. 5,750,751, EP-A-1 044 993 and WO 2006/013061. Moreover, in particular from the document DE-A-27 32 693 coating compositions based on solvents are known which can be crosslinked by polyisocyanates.

Furthermore, the document DE 30 27 308 describes coating compositions which are based on (meth) acrylates which can be crosslinked by oxidation. Furthermore, these polymers have units derived from hydroxyalkyl (meth) acrylates.

In addition to aqueous dispersions, reactive coatings form another group of known coating compositions. Such paints are known for example from EP-O 693 507.

The coating compositions set out above already show a good property spectrum. However, there is a continuing need to improve this property spectrum. For example, coatings made from some of the previously coating compositions were available, an insufficient for high demands hardness. If this is increased by increasing the degree of crosslinking, however, an increasing brittleness occurs. Furthermore, the resistance to chemicals, in particular to improve polar solvents.

In view of the prior art, it is an object of the present invention to provide polymers and coating compositions having excellent properties. These properties include in particular a high chemical resistance of the coatings obtainable from the coating compositions. Here, a high stability compared to many different solvents and to bases and acids should be achieved. In particular, a very good resistance to methyl ethyl ketone (MEK) should be given.

Furthermore, the hardness of the coatings obtainable from the coating compositions should be able to be varied over a wide range. In particular, particularly hard, scratch-resistant coatings should be obtainable from the polymers and coating compositions. Furthermore, coatings which are obtainable from the coating compositions or polymers according to the invention, based on the hardness, should have a relatively low brittleness.

Further, it was therefore an object of the present invention to provide a coating composition which has a particularly long shelf life and durability. Another object is to provide coating compositions that result in coatings with a high gloss. The coatings obtainable from the coating compositions should have a high weather resistance, in particular a high UV resistance.

Furthermore, the coating agents should show good processability over a wide range of temperature and humidity. In relation to the efficiency should the coating compositions show improved environmental compatibility. In particular, the smallest possible amounts of organic solvents should be released into the environment by evaporation.

Another object can be seen to provide coating compositions that can be obtained very inexpensively and on an industrial scale.

These and other objects which are not explicitly mentioned, but which can be readily deduced or developed from the contexts discussed hereinbelow, are achieved by a (meth) acrylate polymer for the production of a coating composition having all the features of patent claim 1. Expedient modifications The (meth) acrylate polymer according to the invention are protected in subclaims. With respect to a coating composition, a process for producing a coating and a coated article, claims 11, 16 and 18 provide a solution to the underlying objects.

The present invention accordingly provides a multifunctional (meth) acrylate polymer for the preparation of a coating composition, which is characterized in that the (meth) acrylate polymer contains 0.5 to 20% by weight of units derived from (meth) acrylic Are derived from monomers having in the alkyl radical at least one double bond and 8 to 40 carbon atoms, 0.1 to 60 wt .-% of units derived from hydroxyl-containing monomers having up to 9 carbon atoms, 0.1 to 95 Wt .-% of units derived from (meth) acrylates having 1 to 12 carbon atoms in the alkyl radical, and

0.1 to 60% by weight of units derived from styrene monomers, each based on the weight of the (meth) acrylate polymer, and the (meth) acrylate polymer has a weight average molecular weight in the range of 2000 to 60000 g / mol. Furthermore, the measures according to the invention make it possible, inter alia, to achieve the following advantages:

The coatings available from the polymers or coating compositions of the present invention show high chemical resistance. In this case, a high stability compared to many different solvents and to bases and acids can be achieved. In particular, a very good resistance to methyl ethyl ketone (MEK) is often given. Likewise, a very good resistance to water can be achieved. Therefore, these can

Coating compositions for the production of protective coatings (protective coatings) are used.

Further, the hardness of the coatings obtainable from the polymers or the coating compositions can be varied over a wide range. In particular, particularly hard, scratch-resistant coatings can be obtained.

Furthermore, coatings which are obtainable from the polymers or coating compositions according to the invention, based on the hardness and the chemical resistance, a relatively low brittleness.

Moreover, the polymers and coating compositions of the present invention have good processability over a wide range of temperature and humidity. In relation to performance, the coating compositions show improved environmental compatibility. Thus, extremely small amounts of organic solvents are released into the environment through evaporation. Here, the coating compositions may comprise a high solids content. In addition, coating compositions according to the invention lead to coatings with a high gloss. The coating compositions of the present invention exhibit particularly long shelf life and durability.

The coatings obtainable from the coating compositions show a high weather resistance, in particular a high UV resistance.

Furthermore, the coating compositions according to the invention are particularly cost-effective and industrially available.

The (meth) acrylate polymer according to the invention comprises from 0.5 to 20% by weight, preferably from 1 to 15% by weight, and very particularly preferably from 2 to 12% by weight, of units derived from (meth) acrylic monomers are derived, which have at least one double bond and 8 to 40 carbon atoms in the alkyl radical, based on the weight of the (meth) acrylate polymer.

The (meth) acrylate polymers can preferably be obtained by free-radical polymerization. Accordingly, the proportion by weight of the respective units comprising these polymers results from the proportions by weight of corresponding monomers used to prepare the polymers, since the proportion by weight of groups derived from initiators or molecular weight regulators can usually be neglected.

The term "multifunctional (meth) acrylate polymer" means that the polymer is supported both by atmospheric oxygen and by crosslinking agents that interfere with the

Hydroxy groups of the (meth) acrylate polymer can react, can be cured.

(Meth) acrylic monomers having at least one double bond and 8 to 40 carbon atoms in the alkyl group are esters or amides of (meth) acrylic acid, their alkyl group has at least one carbon-carbon double bond and 8 to 40 Having carbon atoms. The notation (meth) acrylic acid means methacrylic acid and acrylic acid and mixtures thereof. The alkyl or alcohol or amide radical may preferably have 10 to 30 and more preferably 12 to 20 carbon atoms, which radical may comprise heteroatoms, in particular oxygen, nitrogen or sulfur atoms. The alkyl group may have one, two, three or more carbon-carbon double bonds. The polymerization conditions in which the (meth) acrylate polymer is prepared are preferably chosen so that the largest possible proportion of the double bonds of the alkyl radical is maintained during the polymerization. This can be done, for example, by steric hindrance of the alcohol residue

Double bonds take place. Furthermore, at least a part, preferably all of the double bonds contained in the alkyl radical of the (meth) acrylic monomer, has a lower reactivity in a free-radical polymerization than a (meth) acrylic group, so that preferably no further (meth) acrylic groups in the alkyl radical are included.

The iodine number of the (meth) acrylic monomers to be used for the preparation of the (meth) acrylic polymers which have at least one double bond and 8 to 40 carbon atoms in the alkyl radical is preferably at least 50, more preferably at least 100, and most preferably at least 125 g of iodine / 100 g of (meth) acrylic monomer.

Such (meth) acrylic monomers generally correspond to the formula (I)

wherein the radical R is hydrogen or methyl, X is independently oxygen or a group of the formula NR ', wherein R' is hydrogen or a radical having 1 to 6

Is carbon atoms, and R ^{1 is} a linear or branched radical of 8 to 40, preferably 10 to 30 and particularly preferably 12 to 20 carbon atoms, which has at least one CC double bond.

(Meth) acrylic monomers which have at least one double bond and 8 to 40 carbon atoms in the alkyl radical can be obtained, for example, by esterification of (meth) acrylic acid, reaction of (meth) acryloyl halides or transesterification of (meth) acrylates with alcohols which are at least have a double bond and 8 to 40 carbon atoms. Accordingly, (meth) acrylamides can be obtained by reaction with an amine. These reactions are described, for example, in Ullmann's Encyclopedia of Industrial Chemistry 5th Edition on CD-ROM or F.-B. Chen, G. Bufkin, "Crosslinkable Emulsion Polymers by Autooxidation I", Journal of Applied Polymer Science, Vol. 30, 4571-4582 (1985).

Suitable alcohols include octenol, nonenol, decenol, undecenol, dodecenol, tridecenol, tetradecenol, pentadecenol, hexadecenol, heptadecenol, octadecenol, nonadecenol, icosenol, docosenol, octadiene-ol, nonanoedia-ol, deca- dien-ol, undecadiene-ol, dodecadiene-ol, trideca-dien-ol, tetradeca-dien-ol, pentadeca-dien-ol, hexadeca-dien-ol, heptadeca-dien-ol, octadeca-diene ol, Nonadeca-dien-ol, Ikosa-dien-ol and / or Docosa-dien-ol. These so-called fatty alcohols are sometimes commercially available or can be obtained from fatty acids, this reaction being carried out, for example, in F.-B. Chen, G. Bufkin, Journal of Applied Polymer Science, Vol. 30, 4571-4582 (1985).

The preferred (meth) acrylates obtainable by this process include, in particular, octadiene-yl (meth) acrylate, octadeca-diene-yl (meth) acrylate, octadecanetrienyl (meth) acrylate, Hexadecenyl (meth) acrylate, octadecenyl (meth) acrylate and hexadecadienyl (meth) acrylate.

In addition, (meth) acrylates which have at least one double bond and 8 to 40 carbon atoms in the alkyl radical can also be converted by reaction of unsaturated fatty acids with (meth) acrylates which have reactive groups in the alkyl radical, in particular alcohol radical. The reactive groups include in particular hydroxy groups and epoxy groups. Accordingly, for example, hydroxyalkyl (meth) acrylates such as 3-hydroxypropyl (meth) acrylate, 3,4-dihydroxybutyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2,5-dimethyl -1, 6-hexanediol (meth) acrylate, 1, 10-decanediol (meth) acrylate; or epoxy-containing (meth) acrylates, for example glycidyl (meth) acrylate can be used as starting materials for the preparation of the aforementioned (meth) acrylates.

Suitable fatty acids for reaction with the abovementioned (meth) acrylates are often commercially available and are obtained from natural sources. These include undecylenic acid, palmitoleic acid, oleic acid, elaidic acid, vaccenic acid, icosenoic acid, cetoleic acid, erucic acid, nervonic acid, linoleic acid, linolenic acid, arachidonic acid, timnodonic acid, clupanodonic acid and / or cervonic acid.

The preferred (meth) acrylates obtainable by this process include, in particular, (meth) acryloyloxy-2-hydroxypropyl linoleic acid ester, (meth) acryloyloxy-2-hydroxypropyl linolenic acid ester and (meth) acryloyloxy-2-hydroxypropyl oleic acid ester.

The reaction of the unsaturated fatty acids with (meth) acrylates which have reactive groups in the alkyl radical, in particular alcohol radical, is known per se and is described, for example, in DE-A-41 05 134, DE-A-25 13 516, DE-A-26 38 544 and US 5,750,751.

According to a preferred embodiment, (meth) acrylic monomers of the general formula (II)

wherein R is hydrogen or a methyl group, X ¹ and X ^{2 are} independently oxygen or a group of the formula NR ', wherein R' is hydrogen or a radical having 1 to 6 carbon atoms, with the proviso that at least one of the groups X ¹ and X ² a group of the formula NR ', where R' is hydrogen or a radical having 1 to 6 carbon atoms, Z is a linking group, and R ^{2 is} an unsaturated radical having 9 to 25 carbon atoms, are used.

Surprising advantages can furthermore be achieved by the use of a (meth) acrylic monomer of the general formula (III)

wherein R is hydrogen or a methyl group, X ^{1 is} oxygen or a group of formula NR ', wherein R' is hydrogen or a radical having 1 to 6 carbon atoms, Z is a linking group, R is hydrogen or a radical having 1 to 6 carbon atoms and R ^{2 is} an unsaturated Rest with 9 to 25 carbon atoms, achieve.

The term "radical having 1 to 6 carbon atoms" means a group having 1 to 6 carbon atoms and includes aromatic and heteroaromatic groups as well as alkyl, cycloalkyl, alkoxy, cycloalkoxy, alkenyl, alkanoyl, alkoxycarbonyl groups The groups mentioned may be branched or unbranched, and these groups may also have substituents, in particular halogen atoms or hydroxyl groups. The radicals R 'are preferably alkyl groups. The preferred alkyl groups include the methyl, ethyl, propyl, isopropyl, 1-butyl, 2-butyl, 2-methylpropyl or tert-butyl group.

The group Z preferably represents a linking group comprising 1 to 10, preferably 1 to 5 and most preferably 2 to 3 carbon atoms. These include in particular linear or branched, aliphatic or cycloaliphatic radicals, such as a methylene, ethylene, propylene, iso-propylene, n-butylene, iso-butylene, t-butylene or cyclohexylene group, wherein the Ethylene group is particularly preferred.

The group R ² in formula (II) represents an unsaturated radical having 9 to 25 carbon atoms. These groups include in particular alkenyl, cycloalkenyl, alkenoxy, cycloalkenoxy, alkenoyl and heteroalipatic groups. Furthermore, these groups may have substituents, in particular halogen atoms or hydroxyl groups. The preferred groups include in particular alkenyl groups, such as, for example, the nonenyl, decenyl, undecenyl, dodecenyl, tridecenyl, tetradecenyl, pentadecenyl, hexadecenyl, heptadecenyl, octadecenyl, nonadecenyl, eicosenyl, heneicosenyl, , Docosenyl, octadiene-yl, nonanediazyl, decadiene-yl, undecanediazyl, dodecadienyl, tridecadienyl, tetradecadienyl , Pentadeca-diene-yl, hexadecadienyl, heptadeca-diene-yl, octadeca-dien-yl, nonadeca-dien-yl, eicosa-dien-yl, heneicosa-diene-yl , Docosa-dien-yl, tricosa-dien-yl and / or heptadeca-triene-yl group.

The preferred (meth) acrylic monomers of the formula (II) or (III) include heptadecenyloyloxy-2-ethyl (meth) acrylamide, heptadecadienyloxy-2-ethyl (meth) acrylamide, heptadeca- trienyloxy-2-ethyl (meth) acrylamide, heptadecenyloyloxy-2-ethyl (meth) acrylamide, (meth) acryloyloxy-2-ethyl-palmitoleic acid amide, (meth) acryloyloxy-2-ethyl-oleic acid amide, (meth) acryloyloxy 2-ethyl-icosenoic acid amide, (meth) acryloyloxy-2-ethyl-cetolenic acid amide, (Meth) acryloyloxy-2-ethyl-erucic acid amide, (meth) acryloyloxy-2-ethyl-linoleic acid amide, (meth) acryloyloxy-2-ethyl-linolenic acid amide, (meth) acryloyloxy-2-propyl-palmitoleic acid anhydride, (meth) acryloyloxy-2 -propyl-oleic acid amide, (meth) acryloyloxy-2-propyl-icosenoic acid amide, (meth) acryloyloxy-2-propyl cetoleic acid amide, (meth) acryloyloxy-2-propyl-erucic acid amide, (meth) acryloyloxy-2-propyl-linoleic acid amide and ( meth) acryloyloxy-2-propyl-linolensäureamid.

The notation (meth) acryl stands for acrylic and methacrylic radicals, with methacrylic radicals being preferred. Particularly preferred monomers according to formula (II) or (III) are methacryloyloxy-2-ethyl-oleic acid amide, methacryloyloxy-2-ethyl-linolenic acid amide and / or methacryloyloxy-2-ethyl-linolenic acid amide.

The (meth) acrylic monomers of the formula (II) or (III) can be obtained in particular by multistage processes. In a first step, for example, one or more unsaturated fatty acids or fatty acid esters can be reacted with an amine, for example, ethylenediamine, ethanolamine, propylenediamine or propanolamine, to form an amide. In a second step, the hydroxy group or the amine group of the amide is reacted with a (meth) acrylate, for example methyl (meth) acrylate, to obtain the monomers of the formula (II) or (III). For the preparation of monomers in which X ^{1 is} a group of the formula NR ', wherein R' is hydrogen or a radical having 1 to 6 carbon atoms, and X ^{2 is} oxygen, correspondingly first an alkyl (meth) acrylate, for example methyl (meth ) acrylate, reacted with one of the abovementioned amines to give a (meth) acrylamide having a hydroxy group in the alkyl radical, which is subsequently reacted with an unsaturated fatty acid to give a (meth) acrylic monomer of the formula (II) or (III). Transesterification of alcohols with (meth) acrylates or the preparation of (meth) acrylic acid amides are inter alia in CN 1355161, DE 21 29 425 filed, DE 34 23 443 or EP-AO 534 666 set forth, wherein the reaction conditions described in these publications and the catalysts set forth therein, etc. for the purposes of disclosure in this application. be inserted fertil. Furthermore, these reactions are described in "Synthesis of Acrylic Esters by Transesterification", J. Haken, 1967.

In this case, intermediates obtained, for example carboxamides which have hydroxyl groups in the alkyl radical, can be purified. According to a particular embodiment of the present invention, intermediates obtained can be reacted without expensive purification to the (meth) acrylic monomers of formula (II) or (III).

Furthermore, the (meth) acrylic monomers having 8 to 40, preferably 10 to 30 and particularly preferably 12 to 20 carbon atoms and at least one double bond in the alkyl radical in particular include monomers of the general formula (IV)

wherein R is hydrogen or a methyl group, X is oxygen or a group of the formula NR ', wherein R' is hydrogen or a radical having 1 to 6 carbon atoms, R ^{3 is} an alkylene group having 1 to 22 carbon atoms, Y is oxygen, sulfur or a group of the formula NR ", where R" is hydrogen or a radical having 1 to 6 carbon atoms, and R ^{4 is} an unsaturated radical having at least 8 carbon atoms and at least two double bonds.

In formula (IV), the radical R ^{3 is} an alkylene group having 1 to 22 carbon atoms, preferably 1 to 10, more preferably 2 to 6 carbon atoms. The radical R ³ , according to a particular embodiment of the present invention, represents an alkylene group having 2 to 4, more preferably 2 carbon atoms. The alkylene groups having 1 to 22 carbon atoms include in particular the methylene, ethylene, propylene, iso-propylene, n-butylene, iso-butylene, t-butylene or cyclohexyl groups, with the ethylene group being particularly preferred. The radical R ⁴ comprises at least two CC double bonds which are not part of an aromatic system. Preferably, the radical R ^{4 represents} a group with exactly 8 carbon atoms, which has exactly two double bonds. The radical R ⁴ preferably represents a linear hydrocarbon radical which has no heteroatoms. According to a particular embodiment of the present invention, the radical R ⁴ in formula (IV) may comprise a terminal double bond. In a further variant of the present invention, the radical R ⁴ in formula (IV) can not comprise a terminal double bond. The double bonds contained in the radical R ⁴ may preferably be conjugated. According to a further preferred embodiment of the present invention, the double bonds contained in the radical R ⁴ are not conjugated. Preferred R ⁴ radicals having at least two double bonds include, among others, octa-2,7-dienyl group, octa-3,7-dienyl group, octa-4,7-dienyl group, octa-5,7-dienyl group, octa 2,4-dienyl group, octa-2,5-dienyl group, octa-2,6-dienyl group, octa-3,5-dienyl group, octa-3,6-dienyl group and octa-4,6-dienyl group.

The (meth) acrylic monomers of the general formula (IV) include, inter alia, 2 - [((2-E) octa-2,7-dienyl) methylamino] ethyl 2-methylprop-2-enoate, 2 - [( (2-Z) Octa-2,7-dienyl) methylamino] ethyl 2-methylprop-2-enoate, 2 - [((3-E) octa-3,7-dienyl) methylamino] ethyl-2-methylpropyl 2-enoate, 2 - [((4-Z) octa-4,7-dienyl) methylamino] ethyl 2-methylprop-2-enoate, 2 - [(octa-2,6-dienyl) methylamino] ethyl-2 -methylprop-2-enoate, 2 - [(octa-2,4-dienyl) methylamino] ethyl-2-methylprop-2-enoate, 2 - [(octa-3,5-dienyl) methylamino] ethyl-2-methylprop -2-enoate, 2 - [((2-E) octa-2,7-dienyl) methylamino] ethyl (meth) acrylamide, 2 - [((2-Z) octa-2,7-dienyl) methylamino] ethyl (meth) acrylamide, 2 - [((3-E) octa-3,7-dienyl) methylamino] ethyl (meth) acrylamide, 2 - [((4-Z) octa-4,7-dienyl) methylamino] ethyl (meth) acrylamide, 2 - [(octa-2,6-dienyl) methylamino] ethyl (meth) acrylamide, 2 - [(octa-2,4-dienyl) methylamino] ethyl (meth) acrylamide , 2 - [(octa-3,5-dienyl) methylamino] ethyl (meth) acrylamide, 2 - [((2-E) octa-2,7-dienyl) ethylamino] ethyl 2-methylprop-2-enoate, 2 - [((2-Z) octa-2,7-dienyl) ethylamino] ethyl 2-methylprop-2-enoate, 2 - [((3-E) octa-3,7-dienyl) ethylamino] ethyl-2-methylprop-2-enoate, 2 - [((4-Z) octa-4, 7-dienyl) ethylamino] ethyl 2-methylprop-2-enoate, 2 - [(octa-2,6-dienyl) ethylamino] ethyl 2-methylprop-2-enoate, 2 - [(octa-2,4- dienyl) ethylamino] ethyl 2-methylprop-2-enoate, 2 - [(octa-3,5-dienyl) ethylamino] ethyl 2-methylprop-2-enoate, 2 - [((2-E) octa-2 , 7-dienyl) methylamino] ethyl-prop-2-enoate, 2 - [((2-Z) octa-2,7-dienyl) -methylannino] ethyl-prop-2-enoate, 2 - [((3-E ) Octa-3,7-dienyl) methylamino] ethyl-prop-2-enoate, 2 - [((4-Z) octa-4,7-dienyl) -methylannino] ethyl-prop-2-enoate, 2 - [( Octa-2,6-dienyl) -methylannino] ethyl-prop-2-enoate, 2 - [(octa-2,4-dienyl) methylamino] ethyl-prop-2-enoate, 2 - [(octa-3,5- dienyl) methylannino] ethyl-prop-2-enoate, 2 - ((2-E) octa-2,7-dienyloxy) ethyl-2-methylprop-2-enoate, 2 - ((2-Z) octa-2, 7-dienyloxy) ethyl 2-methylprop-2-enoate, 2 - ((3-E) octa-3,7-dienyloxy) ethyl 2-methylprop-2-enoate, 2 - ((4-Z) octa-4,7-dienyloxy) ethyl 2-methylprop-2-enoate, 2- (octa-2,6-dienyloxy) ethyl-2-methylprop-2-enoate, 2- Octa-2,4-dienyloxy) ethyl 2-methylprop-2-enoate, 2- (octa-3,5-dienyloxy) ethyl-2-methylprop-2-enoate, 2 - ((2-E) octa-2 , 7-dienyloxy) ethyl-prop-2-enoate, 2 - ((2-Z) octa-2,7-dienyloxy) ethyl-prop-2-enoate, 2 - ((3-E) octa-3.7 -dienyloxy) ethyl-prop-2-enoate, 2 - ((4-Z) octa-4,7-dienyloxy) ethyl-prop-2-enoate, 2- (octa-2,6-dienyloxy) ethyl-propanol 2-enoate, 2- (octa-2,4-dienyloxy) ethyl-prop-2-enoate and 2- (octa-3,5-dienyloxy) ethyl-prop-2-enoate.

The (meth) acrylic monomers of the formula (IV) set out above can be obtained in particular by processes in which (meth) acrylic acid or a (meth) acrylate, in particular methyl (meth) acrylate or ethyl (meth) acrylate with an alcohol and / or an amine is reacted. These reactions have been previously stated.

The starting material to be reacted with the (meth) acrylic acid or the (meth) acrylate may advantageously correspond to the formula (V),

HX-R-YR ⁴ (V), wherein X is oxygen or a group of the formula NR ', wherein R' is hydrogen or a radical having 1 to 6 carbon atoms, R ^{3 is} an alkylene group having 1 to 22 carbon atoms, Y is oxygen, sulfur or a group of the formula NR ", where R "Represents hydrogen or a radical having 1 to 6 carbon atoms, and R ^{4 is} a at least double unsaturated radical having at least 8 carbon atoms.

With regard to the meaning of preferred radicals R ', R ", R ³ , Y and R ⁴ , reference is made to the description of the formula (IV).

The preferred starting materials of the formula (V) include (methyl (octa-2,7-dienyl) amino) ethanol, (ethyl (octa-2,7-dienyl) amino) ethanol, 2-octa-2,7-dienyloxyethanol, (methyl octa-2,7-dienyl) amino () ethylamine,

(Methyl (octa-3,7-dienyl) amino) ethanol, (ethyl (octa-3,7-dienyl) amino) ethanol, 2-octa-3,7-dienyloxyethanol, (methyl (octa-3,7-dienyl ) amino) ethylamine, (methyl (octa-4,7-dienyl) amino) ethanol, (ethyl (octa-4,7-dienyl) amino) ethanol, 2-octa-4,7-dienyloxyethanol, (methyl (octa 4,7-dienyl) amino) ethylamine, (methyl (octa-5,7-dienyl) amino) ethanol, (ethyl (octa-5,7-dienyl) amino) ethanol, 2-octa-5,7-dienyloxyethanol, (Methyl (octa-5,7-dienyl) amino) ethylamine, (methyl (octa-2,6-dienyl) amino) ethanol, (ethyl (octa-2,6-dienyl) amino) ethanol, 2-octa-2 , 6-dienyloxyethanol, (methyl (octa-2,6-dienyl) amino) ethylamine,

(Methyl (octa-2,5-dienyl) amino) ethanol, (ethyl (octa-2,5-dienyl) amino) ethanol, 2-octa-2,5-dienyloxyethanol, (methyl (octa-2,5-dienyl ) amino) ethylamine, (methyl (octa-2,4-dienyl) amino) ethanol, (ethyl (octa-2,4-dienyl) amino) ethanol, 2-octa-2,4-dienyloxyethanol, (methyl (octa) 2,4-dienyl) amino) ethylamine, (methyl (octa-3,6-dienyl) amino) ethanol, (ethyl (octa-3,6-dienyl) amino) ethanol, 2-octa-3,6-dienyloxyethanol, (Methyl (octa-3,6-dienyl) amino) ethylamine, (methyl (octa-3,5-dienyl) amino) ethanol, (ethyl (octa-3,5-dienyl) amino) ethanol, 2-octa-3 , 5-dienyloxyethanol, (methyl (octa-3,5-dienyl) amino) ethylamine, (Methyl (octa-4,6-dienyl) amino) ethanol, (ethyl (octa-4,6-dienyl) amino) ethanol, 2-octa-4,6-dienyloxyethanol and (methyl (octa-4,6-dienyl ) amino) ethylannin. The educts of the formula (V) can be used individually or as a mixture.

The educts according to formula (V) can be obtained inter alia by known methods of telomerization of 1,3-butadiene. Here, the term "telomerization" means the reaction of compounds with conjugated double bonds in the presence of nucleophiles The processes set forth in the publications WO 2004/002931, WO 03/031379 and WO 02/100803, in particular the catalysts used for the reaction and the reaction conditions, such as pressure and temperature, are included in the present application for purposes of disclosure.

Preferably, the telomerization of 1, 3-butadiene using metal compounds comprising metals of the 8th to 10th group of the Periodic Table of the Elements can be carried out as a catalyst, wherein palladium compounds, in particular Palladiumcarbenkomplexe, which are set forth in more detail in the above-mentioned documents, can be used with particular preference.

Particularly suitable nucleophiles are dialcohols such as ethylene glycol, 1,2-propanediol, 1,3-propanediol; Diamines such as ethylenediamine, N-methyl-ethylenediamine, N ₁ N'-dimethylethylenediamine or hexamethylenediamine; or aminoalkanols, such as aminoethanol, N-methylaminoethanol, N-ethylaminoethanol, aminopropanol, N-methylaminopropanol or N-ethylaminopropanol.

When using (meth) acrylic acid as the nucleophile, for example octadienyl (meth) acrylates can be obtained, which are particularly suitable as (meth) acrylic monomers having 8 to 40 carbon atoms. The temperature at which the telomerization reaction is carried out is between 10 and 180 ^° C., preferably between 30 and 120 ^° C., more preferably between 40 and 100 ^° C. The reaction pressure is 1 to 300 bar, preferably 1 to 120 bar, especially preferably 1 to 64 bar and most preferably 1 to 20 bar.

The preparation of isomers from compounds having an octa-2,7-dienyl group can be accomplished by isomerization of the double bonds contained in the compounds having an octa-2,7-dienyl group.

The above-mentioned (meth) acrylic monomers having at least one double bond and 8 to 40 carbon atoms in the alkyl group may be used singly or as a mixture of two or more monomers.

Furthermore, the (meth) acrylic polymer to be used according to the invention in the coating composition comprises units derived from hydroxyl-containing monomers having up to 9 carbon atoms.

Hydroxyl-containing monomers are compounds which have at least one hydroxyl group in addition to a carbon-carbon double bond. These compounds have preferably 3 to 9, particularly preferably 4 to 8 and very particularly preferably 5 to 7 carbon atoms. The carbon group of these compounds may be linear, branched or cyclic. Furthermore, these compounds may have aromatic or heteroaromatic groups. In addition to olefinic alcohols, such as allyl alcohol, these compounds include in particular unsaturated esters and ethers having a hydroxy group.

These preferably include (meth) acrylates having a hydroxy group in the alkyl radical, in particular

2-hydroxyethyl (meth) acrylate, preferably 2-hydroxyethyl methacrylate (HEMA), hydroxypropyl (meth) acrylate, for example 2-hydroxypropyl (meth) acrylate and Hydroxypropyl (meth) acrylate, preferably hydroxypropyl methacrylate (HPMA), hydroxybutyl (meth) acrylate, preferably hydroxybutyl methacrylate (HBMA), 3,4-dihydroxybutyl (meth) acrylate and glycerol mono (meth) acrylate.

The (meth) acrylate polymer comprises from 0.1 to 60% by weight, preferably from 5 to 55% by weight and more preferably from 10 to 40% by weight of units derived from hydroxyl-containing monomers.

Of particular interest here are in particular (meth) acrylate polymers which are characterized by a high weight ratio of units derived from hydroxyl-containing monomers to the units derived from (meth) acrylic monomers which in the alkyl radical are at least have a double bond and 8 to 40 carbon atoms. In a particular aspect, the weight ratio of units derived from hydroxy-containing monomers to units derived from (meth) acrylic monomers having at least one double bond and from 8 to 40 carbon atoms in the alkyl radical is preferably greater than 1, more preferably greater than 2. More preferably, the weight ratio of units derived from hydroxy-containing monomers to units derived from (meth) acrylic monomers having at least one double bond in the alkyl radical and 8 have up to 40 carbon atoms, in the range from 1: 1 to 5: 1, more preferably 2: 1 to 4: 1.

In addition to the (meth) acrylic monomers described above, which have at least one double bond and 8 to 40 carbon atoms in the alkyl radical, and the hydroxyl-containing monomers, (meth) acrylate polymers to be used according to the invention have from 0.1 to 95% by weight. Units derived from (meth) acrylates having 1 to 12 carbon atoms in the alkyl radical, which have no double bonds or hetero atoms in the alkyl radical. Here are (meth) acrylates having 1 to 10 carbon atoms in the alkyl group, which have no double bonds or heteroatoms in the alkyl radical, preferably.

The (meth) acrylates having 1 to 12 carbon atoms in the alkyl radical which have no double bonds or heteroatoms in the alkyl radical include, inter alia, (meth) acrylates having a linear or branched alkyl radical, such as, for example, methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, iso-propyl (meth) acrylate, n-butyl (meth) acrylate, iso-butyl (meth) acrylate, tert-butyl (meth) acrylate and pentyl (meth) acrylate, hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, heptyl (meth) acrylate, octyl (meth) acrylate, 3-isopropyl-propyl (meth) acrylate, nonyl (meth) acrylate, decyl (meth) acrylate, undecyl (meth ) acrylate, 5-methylundecyl (meth) acrylate, dodecyl (meth) acrylate; and

Cycloalkyl (meth) acrylates, such as cyclopentyl (meth) acrylate, cyclohexyl (meth) acrylate, cyclohexyl (meth) acrylates having at least one substituent on the ring, such as tert-butylcyclohexyl (meth) acrylate and trimethylcyclohexyl (meth) acrylate, norbornene nyl (meth) acrylate, methylnorbornyl (meth) acrylate and dimethylnorbornyl (meth) acrylate, bornyl (meth) acrylate, 1-adamantyl (meth) acrylate, 2-adamantyl (meth) acrylate, menthyl (meth) acrylate and isobornyl (meth) acrylate. The (meth) acrylates having 1 to 12 carbon atoms in the alkyl radical described above can be used individually or as a mixture.

Surprising advantages in particular (meth) acrylate polymers, preferably 5 wt .-% to 90 wt .-%, preferably 10 wt .-% to 70 wt .-% and most preferably 20 wt .-% to 60 wt. -% of units derived from (meth) acrylates having 1 to 12 carbon atoms in the alkyl radical which have no double bonds or heteroatoms in the alkyl radical, based on the weight of the (meth) acrylate polymer.

Also of particular interest are (meth) acrylate polymers which preferably comprise from 1 to 50% by weight, more preferably from 5 to 40% by weight, of units derived from cycloalkyl (meth) acrylates, in particular cyclohexyl methacrylate, cyclohexyl acrylate Cyclohexyl (meth) acrylates having at least one substituent on the ring, such as tert-butylcyclohexyl methacrylate and thmethylcyclohexyl (meth) acrylate, preferably 2,4,6-Thmethylcyclohexylmethacrylat, isobornyl acrylate and / or isobornyl methacrylate are derived.

According to a particular aspect of the present invention, the (meth) acrylates having 1 to 12 carbon atoms in the alkyl radical which do not have double bonds or heteroatoms in the alkyl radical set out above can be selected such that a (meth) acrylate polymer consisting of these (meth) acrylates having 1 to 12 carbon atoms in the alkyl radical having a glass transition temperature of at least 40 ⁰ C, preferably at least 50 ⁰ C and particularly preferably at least 60 ° C.

The glass transition temperature Tg of the polymer can be determined in a known manner by means of differential scanning calohmetry (DSC), in particular according to DIN EN ISO 11357. Preferably, the glass transition temperature can be determined as the center of the glass stage of the second heating curve at a heating rate of 10 ⁰ C per minute. Furthermore, the glass transition temperature Tg can also be calculated approximately in advance by means of the Fox equation. After Fox TG, Bull. Am. Physics Soc. 1, 3, page 123 (1956) applies:

1 = - XJ, - + - X -2 ₂ - + ... +. X "

Tg Tg ₁ Tg Tg _n ₂ wherein X _n is the mass fraction designated n (wt .-% / 100) of monomer n and Tg _{n is} the glass transition temperature in Kelvin of the homopolymer of the monomer. Further helpful information can be found by the person skilled in the art in Polymer Handbook 2 ^nd Edition, J. Wiley & Sons, New York (1975), which indicates Tg values for the most common homopolymers. According to this handbook, for example, poly (methyl methacrylate) has a glass transition temperature of 378 K, poly (butyl methacrylate) of 297 K, poly (isobornyl methacrylate) of 383 K, poly (isobornyl acrylate) of 367 K and poly (cyclohexyl methacrylate) of 356 K up. To determine the glass transition temperature, the polymer, which consists of (Meth) acrylates having 1 to 12 carbon atoms in the alkyl radical which have no double bonds or heteroatoms in the alkyl radical, a weight average molecular weight of at least 100,000 g / mol and a number average molecular weight of at least 80,000 g / mol.

The choice of the type and amount of the above-described (meth) acrylates having 1 to 12 carbon atoms in the alkyl radical which have no double bonds or heteroatoms in the alkyl radical can be selected via the formula of Fox et al. respectively.

Further, the (meth) acrylate polymer of the present invention comprises 0.1 to 60% by weight of units derived from styrene monomers based on the weight of the (meth) acrylate polymer.

Styrenic monomers are known in the art. These monomers include, for example, styrene, substituted styrenes having an alkyl substituent in the side chain, such as. As α-methyl styrene and α-ethyl styrene, substituted styrenes having an alkyl substituent on the ring, such as vinyl toluene and p-methyl styrene, halogenated styrenes, such as monochlorostyrenes, dichlorostyrenes, tribromostyrenes and tetrabromostyrenes.

According to a particular modification of the present invention, the

(Meth) acrylate polymer 1 to 55 wt .-%, more preferably 5 to 50 wt .-% and most preferably 10 to 40 wt .-% of units which styrenic, in particular of styrene, substituted styrenes with an alkyl substituent in the side chain, substituted styrenes with an alkyl substituent on the ring and / or halogenated styrenes, based on the total weight of the (meth) acrylate polymer.

In addition to the compulsory repeating units set forth above, the (meth) acrylate polymer may comprise units derived from comonomers. These comonomers differ from the units of the polyme- ren, but can be copolymerized with the monomers set forth above. Preferably, the (meth) acrylate polymer comprises at most 30% by weight, more preferably at most 15% by weight of units derived from comonomers.

A group of preferred comonomers have an acid group. Acid group-containing monomers are compounds which can preferably be radically copolymerized with the (meth) acrylic monomers set forth above. These include, for example, monomers having a sulfonic acid group, such as vinylsulfonic acid; Monomers having a phosphonic acid group, such as vinylphosphonic acid and unsaturated carboxylic acids, such as methacrylic acid, acrylic acid, fumaric acid and maleic acid. Particularly preferred are methacrylic acid and acrylic acid. The acid group-containing monomers can be used individually or as a mixture of two, three or more acid group-containing monomers.

Of particular interest are, in particular, (meth) acrylate polymers which contain 0 to 10% by weight, preferably 0.5 to 8% by weight and more preferably 1 to 5% by weight, of units derived from acid groups Monomers are derived, based on the total weight of the (meth) acrylate polymer.

Another class of comonomers are (meth) acrylates having at least 13 carbon atoms in the alkyl radical, which are derived from saturated alcohols, such as 2-methyldodecyl (meth) acrylate, tridecyl (meth) acrylate, 5-methyltridecyl (meth) acrylate, tetradecyl ( meth) acrylate, pentadecyl (meth) acrylate, hexadecyl (meth) acrylate, 2-methylhexadecyl (meth) acrylate, heptadecyl (meth) acrylate, 5-iso-propylheptadecyl (meth) acrylate, 4-tert-butyloctadecyl (meth) acrylate , 5-Ethyloctadecyl (meth) acrylate, 3-iso-propyloctadecyl (meth) acrylate, octadecyl (meth) acrylate, nonadecyl (meth) acrylate, eicosyl (meth) acrylate, cetyleicosyl (meth) acrylate, stearyleicosyl (meth) acrylate, docosyl (meth) acrylate and / or eicosyltetratriacontyl (meth) acrylate; Cycloalkyl (meth) acrylates, such as 2,4,5-tri-t-butyl-3-vinylcyclohexyl (meth) acrylate, 2,3,4,5-tetra-t-butylcyclohexyl (meth) acrylate; heterocyclic (meth) acrylates such as 2- (1-imidazolyl) ethyl (neth) acrylate, 2- (4-morpholinyl) ethyl (meth) acrylate, 1- (2-methacryloyloxyethyl) -2-pyrrolidone; Nitriles of (meth) acrylic acid and other nitrogen-containing methacrylates such as N- (methacryloyloxyethyl) diisobutylketimine, N- (methacryloyloxyethyl) dihexadecylketimine, methacryloylamidoacetonitrile, 2-methacryloyloxyethylmethylcyanamide, cyanomethylmethacrylate;

Aryl (meth) acrylates, such as benzyl (meth) acrylate or phenyl (meth) acrylate, wherein the aryl radicals may each be unsubstituted or substituted up to four times; polyalkoxylated derivatives of (meth) acrylic acid, in particular polypropylene glycol mono (meth) acrylate having 2 to 10, preferably 3 to 6 propylene oxide units, preferably polypropylene glycol monomethacrylate with about 5 propylene oxide units (PPM5), polyethylene glycol mono (meth) acrylate with 2 to 10, preferably 3 to 6 ethylene oxide units, preferably polyethylene glycol monomethacrylate with about 5 ethylene oxide units (PEM5), polybutylene glycol mono (meth) acrylate, polyethylene glycol polypropylene glycol mono (meth) acrylate; (Meth) acrylamides, in particular N-methylol (meth) acrylamide, N ₁ N- dimethylaminopropyl (meth) acrylamide, tert-butylaminoethyl methacrylate, methacrylamide and acrylamide; and

(Meth) acrylates derived from saturated fatty acids or fatty acid amides, such as (meth) acryloyloxy-2-hydroxypropyl-palmitic acid ester, (meth) acryloyloxy-2-hydroxypropyl-stearic acid ester and (meth) acryloyloxy-2-hydroxypropyl-laurin ester, pentadecyloyloxy- 2-ethyl (meth) acrylamide, heptadecyloyloxy-2-ethyl (meth) acrylamide, (meth) acryloyloxy-2-ethyl-lauric acid amide, (meth) acryloyloxy-2-ethyl-myristic acid amide, (meth) acryloyloxy-2-ethyl -palmitic acid amide, (meth) acryloyloxy-2-ethyl-stearic acid amide, (meth) acryloyloxy-2-propyl lauramide, (meth) acryloyloxy-2-propyl-myristic acid amide, (meth) acryloyloxy-2-propyl palmitic acid amide and (meth) acryloyloxy-2-propyl-stearic acid amide. The comonomers also include vinyl esters such as vinyl acetate, vinyl chloride, vinyl versatate, ethylene vinyl acetate, ethylene vinyl chloride;

Maleic acid derivatives, such as, for example, maleic anhydride, esters of maleic acid, for example dimethyl maleate, methylmaleic anhydride; and fumaric acid derivatives, such as dimethyl fumarate.

Heterocyclic vinyl compounds, such as 2-vinylpyridine, 3-vinylpyridine, 2-methyl-5-vinylpyridine, 3-ethyl-4-vinylpyridine, 2,3-dimethyl-5-vinylpyridine, vinylpyrimidine, vinylpiperidine, 9-vinylcarbazole, 3-vinylcarbazole, 4-vinylcarbazole, 1-vinylimidazole, 2-methyl-1-vinylimidazole, N-vinylpyrrolidone, 2-vinylpyrrolidone, N-vinylpyrrolidine, 3-vinylpyrrolidine, N-vinylcaprolactam, N-vinylbutyrolactam, vinyloxolane, vinylfuran, vinylthiophene, vinylthiolane, vinylthiazoles and hydrogenated vinylthiazoles, vinyloxazoles and hydrogenated vinyloxazoles; Maleimide, methylmaleimide; Vinyl and isoprenyl ethers; and

Vinyl halides such as vinyl chloride, vinyl fluoride, vinylidene chloride and vinylidene fluoride are further examples of comonomers.

Moreover, for producing the (meth) acrylate polymer, monomer mixtures having a very small proportion of (meth) acrylates having two or more carbon-carbon double bonds having a reactivity identical to a (meth) acrylate group are preferred exhibit. According to a particular modification of the present invention, the proportion of compounds having two or more (meth) acrylate groups is preferably at most 5 wt .-%, in particular at most 2 wt .-%, particularly preferably at most 1 wt .-%, particularly preferred at most 0.5% by weight and most preferably at most 0.1% by weight, based on the total weight of the monomers. The (meth) acrylate polymer according to the invention has a weight average molecular weight in the range from 2000 g / mol to 60000 g / mol, preferably in the range from 4000 g / mol to 40 000 g / mol and more preferably in the range from 5000 g / mol to 20000 g / mol. The number average molecular weight of preferred (meth) acrylate polymers is in the range of 1,000 to 50,000 g / mol, more preferably in the range of 1,500 to 10,000 g / mol. Also of particular interest are (meth) acrylate polymers which have a polydispersity index M _w / M _n in the range from 1 to 5, particularly preferably in the range from 1.5 to 3. The molecular weight can be determined by means of gel permeation chromatography (GPC) against a PMMA standard.

According to a particular aspect of the present invention, the (meth) acrylate polymer may have a molecular weight distribution having at least 2 peaks, as measured by gel permeation chromatography.

The glass transition temperature of the (meth) acrylate polymer is preferably in the range from 20 ^° C. to 90 ^° C., more preferably in the range from 25 to 85 ^° C. and most preferably in the range from 30 to 80 ^° C. The glass transition temperature can be determined by way of the art and the proportion of monomers used to prepare the (meth) acrylate polymer. In this case, the glass transition temperature Tg of the (meth) acrylic polymer can be determined in a known manner by means of differential scanning calorimetry (DSC), in particular according to DIN EN ISO 11357. Preferably, the glass transition temperature can be determined as the center of the glass stage of the second heating curve at a heating rate of 10 ⁰ C per minute. Furthermore, the glass transition temperature Tg can also be calculated approximately in advance by means of the previously described Fox equation.

The iodine number of preferred (meth) acrylate polymers is preferably in the range of 1 to 300 g of iodine per 100 g of polymer, preferably in the range of 2 to 250 g of iodine per 100 g of polymer, more preferably 5 to 100 g of iodine per 100 g of polymer and most preferably 10 to 50 g of iodine per 100 g of polymer, measured in accordance with DIN 53241 -1.

The hydroxyl number of the polymer may preferably be in the range of 3 to 300 mg KOH / g, more preferably 20 to 200 mg KOH / g, and most preferably in the range of 40 to 150 mg KOH / g. The hydroxyl number can be determined according to DIN EN ISO 4629.

The (meth) acrylate polymers to be used according to the invention can be prepared in particular by solution polymerizations, bulk polymerizations or

Emulsion polymerizations can be obtained, with surprising advantages can be achieved by a radical solution polymerization. These methods are set forth in Ullmanns Encyclopedia of Industhal Chemistry, Sixth Edition.

In addition to methods of classical radical polymerization and related methods of controlled radical polymerization, such as ATRP (= Atom Transfer Radical Polymerization), NMP (Nitroxide-mediated polymerization) or RAFT (= Reversible Addition Fragmentation Chain Transfer) can be used to prepare the polymers.

To carry out a customary free-radical polymerization, a polymerization initiator is used, it being possible in many cases in addition to use a molecular weight regulator.

Useful initiators include the azo initiators well known in the art, such as AIBN and 1,1-azobiscyclohexanecarbonitrile, and peroxy compounds such as methyl ethyl ketone peroxide, acetylacetone peroxide, dilauryl peroxide, tert-butyl per-2-ethylhexanoate, ketone peroxide, tert-butyl peroctoate , Methyl isobutyl ketone peroxide, cyclohexanone peroxide, dibenzoyl peroxide, tert-butyl peroxybenzoate, tert-butyl peroxyisopropyl carbonate, 2,5-bis (2-ethylhexanoylperoxy) -2,5-dimethylhexane, tert-butyl peroxy-2-ethylhexanoate, tert-butylperoxy-3,5,5-trin-ethylhexanoate, dicumyl peroxide, 1,1-bis (tert-butylperoxy) cyclohexane, 1,1-bis (tert-butylperoxy) 3,3,5-trimethylcyclohexane, cumyl hydroperoxide, tert-butyl hydroperoxide, bis (4-tert-butylcyclohexyl) peroxydicarbonate, mixtures of two or more of the abovementioned compounds with one another and mixtures of the abovementioned compounds with unspecified compounds which are also free radicals can form.

The initiators mentioned can be used both individually and in mixtures. They are preferably used in an amount of 0.05 to 10.0 wt .-%, particularly preferably 3 to 8 wt .-%, based on the total weight of the monomers. It is also preferable to carry out the polymerization with a mixture of different polymerization initiators having a different half-life.

The sulfur-free molecular weight regulators include, but are not limited to, dimeric α-methylstyrene (2,4-diphenyl-4-methyl-1-pentene), enol ethers of aliphatic and / or cycloaliphatic aldehydes, terpenes, β-terpinene, Terpinolene, 1,4-cyclohexadiene, 1,4-dihydronaphthalene, 1, 4,5,8-tetrahydronaphthalene, 2,5-dihydrofuran, 2,5-dimethylfuran and / or 3,6-dihydro-2H-pyran, is preferred dimeric α-methylstyrene.

The sulfur-containing molecular weight regulators used may preferably be mercapto compounds, dialkyl sulfides, dialkyl disulfides and / or diaryl sulfides. The following polymerization regulators are exemplified: di-n-butylsulfide, di-n-octylsulfide, diphenylsulfide, thiodiglycol, ethylthioethanol, diisopropyl disulfide, di-n-butyl disulfide, di-n-hexyl disulfide, diacetyl disulfide, diethanol sulfide, di-t-butyl trisulfide and dimethyl sulfoxide. Preferred compounds used as molecular weight regulators are mercapto compounds, dialkyl sulfides, dialkyl disulfides and / or diaryl sulfides. Examples of these compounds are ethyl thioglycolate, 2-ethylhexyl thioglycolate, cysteine, 2-mercaptoethanol, 1, 3-mercaptopropanol, 3-mercaptopropane-1, 2-diol, 1, 4-mercaptobutanol, mercaptoacetic acid, 3-mercaptopropionic acid, mercaptoboric acid. acid, thioglycerol, thioacetic acid, thiourea and alkylmercaptans such as n-butylmercaptan, n-hexylmercaptan or n-dodecylmercaptan. Particularly preferred (meth) acrylic polymerization regulators are mercapto alcohols and mercapto-carboxylic acids.

The molecular weight regulators are preferably used in amounts of 0.05 to 10, more preferably 0.1 to 5 wt .-% and most preferably in the range of 0.5 to 3, based on the monomers used in the polymerization. Of course, mixtures of polymerization regulators can also be used in the polymerization.

The polymerization can be carried out at atmospheric pressure, lower or higher pressure. The polymerization temperature is not critical. In general, however, it is in the range of -20 ° - 200 ⁰ C, preferably 50 ° - 150 ⁰ C and particularly preferably 80 ° - 130 ⁰ C.

The polymerization can be carried out with or without solvent. The term of the solvent is to be understood here broadly. The preferred solvents include in particular aromatic hydrocarbons, such as toluene, xylene; Esters, in particular acetates, preferably butyl acetate, ethyl acetate, propyl acetate; Ketones, preferably ethyl methyl ketone, acetone, methyl isobutyl ketone or cyclohexanone; Alcohols, especially isopropanol, n-butanol, isobutanol; Ethers, in particular glycolomethyl ether, glycol monoethyl ether, glycol monobutyl ether; Aliphatics, preferably pentane, hexane, cycloalkanes and substituted cycloalkanes, for example cyclohexane; Mixtures of aliphatics and / or aromatics, preferably naphtha; Gasoline, biodiesel; but also plasticizers such as low molecular weight polypropylene glycols or phthalates.

Of particular interest are, in particular, coating compositions which are preferably 40 to 80% by weight, more preferably 50 to 75% by weight, at least a (meth) acrylate polymer having units derived from (meth) acrylic monomers having at least one double bond and 8 to 40 carbon atoms in the alkyl radical.

The coating compositions or (meth) acrylate

In particular, polymers can be crosslinked by crosslinking agents that can react with the hydroxy groups of the polymer.

For example, the present polymers having hydroxy groups can be crosslinked with compounds having two or more N-methylolamide groups, such as polymers having repeating units derived from N-methylolmethacrylamide. Conventionally, temperatures of at least 100 ^° C., preferably at least, are used for crosslinking.

Furthermore, the polymers according to the invention can be crosslinked with hydroxyl groups with polyanhydrides, such as, for example, dianhydrides, in particular pyromellitic dianhydride, or polymers with two or more units derived from maleic anhydride. The crosslinking with polyanhydrides may preferably be at an elevated temperature, for example at least 100 ⁰ C., preferably at least 120 ° C.

Another class of crosslinking agents are melamine or urea derivatives. The crosslinking with melamine or urea derivatives may preferably be at an elevated temperature, for example at least 100 ⁰ C., preferably at least 120 ° C.

The preferred crosslinking agents include in particular polyisocyanates or compounds which release polyisocyanates. Polyisocyanates are compounds having at least 2 isocyanate groups. The polyisocyanates which can be used according to the invention may comprise any desired aromatic, aliphatic, cycloaliphatic and / or (cyclo) aliphatic polyisocyanates.

The preferred aromatic polyisocyanates include 1, 3 and

1, 4-phenylene diisocyanate, 1, 5-naphthylene diisocyanate, tolidine diisocyanate, 2,6-toluene diisocyanate, 2,4-toluene diisocyanate (2,4-TDI),

2,4'-diphenylmethane diisocyanate (2,4'-MDI), 4,4'-diphenylmethane diisocyanate, the mixtures of monomeric diphenylmethane diisocyanates (MDI) and oligomeric diphenylmethane diisocyanates (polymer-MDI), xylylene diisocyanate, tetramethylxylylene diisocyanate and triisocyanatotoluene.

Preferred aliphatic polyisocyanates have 3 to 16 carbon atoms, preferably 4 to 12 carbon atoms, in the linear or branched alkylene radical and suitable cycloaliphatic or (cyclo) aliphatic diisocyanates advantageously 4 to 18 carbon atoms, preferably 6 to 15 carbon atoms, in the cycloalkylene radical. Under (cyclo) aliphatic diisocyanates, the skilled worker understands at the same time cyclic and aliphatic bound NCO groups, as z. B. is the case with isophorone diisocyanate. In contrast, is meant by cycloaliphatic diisocyanates those which have only directly attached to the cycloaliphatic ring NCO groups, for. B. H ₁₂ MDI. Examples are cyclohexane diisocyanate, methylcyclohexane diisocyanate, ethylcyclohexane diisocyanate, propylcyclohexane diisocyanate, methyldiethylcyclohexane diisocyanate, propane diisocyanate, butane diisocyanate, pentane diisocyanate, hexane diisocyanate, heptane diisocyanate, octane diisocyanate, nonane diisocyanate, nonane triisocyanate, such as 4-isocyanatomethyl-1, 8-octane diisocyanate (TIN), decane and triisocyanate , Undecandric and triisocyanate, dodecanedi and triisocyanates.

Preference is given to isophorone diisocyanate (IPDI), hexamethylene diisocyanate (HDI), diisocyanatodicyclohexylmethane (H ₁₂ MDI), 2-methylpentane diisocyanate (MPDI), 2,2,4-thmethylhexamethylene diisocyanate / 2,4,4-thmethylhexamethylene diisocyanate (TMDI), norbornane diisocyanate (NBDI). Very particular preference is given to using IPDI, HDI, TMDI and H ₁₂ MDI, it also being possible to use the isocyanurates.

Also suitable are 4-methylcyclohexane-1, 3-diisocyanate, 2-butyl-2-ethylpentamethylene diisocyanate, 3 (4) isocyanatomethyl-1-methylcyclohexyl isocyanate, 2-isocyanatopropylcyclohexyl isocyanate, 2,4'-methylene-bis (cyclohexyl) diisocyanate, 1, 4-diisocyanato-4-methyl-pentane.

Preferred aliphatic, cycloaliphatic and araliphatic, d. H. Aryl-substituted aliphatic diisocyanates are described for example in Houben-Weyl, Methods of Organic Chemistry, Volume 14/2, pages 61-70 and in the article by W. Siefken, Justus Liebigs Annalen der Chemie 562, 75-136.

Of course, mixtures of the polyisocyanates can be used.

Furthermore, preference is given to using oligoisocyanates or polyisocyanates which are prepared from the abovementioned diisocyanates or polyisocyanates or mixtures thereof by linking by means of urethane, allophanate, urea, biuret, uretdione, amide, isocyanurate, carbodiimide, Uretonimine, oxadiazinetrione or Iminooxadiazindion structures produce. This preferred class of polyisocyanates can be prepared by dimerization, thimerization, allophanatization, biuretization and / or urethanization of simple diisocyanates compounds having more than two isocyanate groups per molecule, for example, the reaction products of these simple diisocyanates, such as. B. IPDI, TMDI, HDI and / or H ₁₂ MDI with polyhydric alcohols (eg., Glycerin, trimethylolpropane, pentaerythritol) or polyhydric polyamines, or the Triisocyanura- te by trimerization of simple diisocyanates, such as IPDI , HDI and H ₁₂ MDI.

Coating agents which preferably contain from 0.5 to 10% by weight, particularly preferably from 2 to 7% by weight, of crosslinking agent are therefore of particular interest. When polyisocyanates are used as crosslinking agents, the reaction of the (meth) acrylate polymers with the organic polyisocyanates can be carried out here with 0.5 to 1.1 NCO group per hydroxyl group, depending on the intended use of the reaction products. The reaction is preferably carried out in such a way that the amounts of the organic polyisocyanate, based on the total hydroxy content of the components present in the reaction mixture per hydroxyl group, are present in an amount of from 0.7 to 1.0 isocyanate groups.

The coating compositions of the invention do not require siccatives, but these may be included as an optional ingredient in the compositions. These include in particular organometallic compounds, for example metal soaps of transition metals, such as cobalt, manganese, lead, zirconium, iron, cerium; Alkali or alkaline earth metals, such as lithium, potassium and calcium. As an example, mention may be made of cobalt naphthalate and cobalt acetate. The siccatives can be used individually or as a mixture, with particular preference being given to mixtures containing cobalt, zirconium and lithium salts.

The proportion of siccatives in preferred coating compositions may preferably be in the range of greater than 0 to 5% by weight, more preferably in the range of greater than 0 to 3% by weight and most preferably in the range of greater than 0 to 0.1% by weight. %, based on the weight of the polymer.

In addition to the (meth) acrylate polymers of the invention, the coating compositions according to the invention may comprise solvents. Examples of preferred solvents have been previously set forth in the context of a radical polymerization, so that reference is hereby made. The proportion of solvent in preferred coating compositions can be in particular in the range from 0 to 60 Wt .-%, particularly preferably in the range of 5 to 40 wt .-%, based on the total weight of the coating composition.

The coating compositions according to the invention may also contain customary auxiliaries and additives such as rheology modifiers, defoamers, water scavengers (moisture-removing additives, orthoesters), deaerators, pigment wetting agents, dispersing additives, substrate wetting agents, lubricants and leveling additives, preferably each in an amount of 0 wt. -% to 3 wt .-%, based on the total formulation, may be included, as well as water repellents, plasticizers, thinners, in particular reactive diluents, UV stabilizers and adhesion promoters, each preferably in an amount of 0 wt .-% to 20 wt. -%, based on the total formulation may be included.

Furthermore, the coating compositions of the invention may contain conventional fillers and pigments, e.g. Talc, calcium carbonate, titanium dioxide, carbon black, etc. in an amount of up to 50% by weight of the total composition.

The coating compositions according to the invention are distinguished by an outstanding property spectrum, which in particular comprises excellent processability and excellent quality of the coating obtained. Preferred coating agents can be processed in a wide temperature window, which preferably has a width of at least 20 ^° C., in particular at least 30 ^° C., without impairing the quality of the coating, which is distinguished, in particular, by high solvent and water resistance , Accordingly, a preferred coating composition may be at a temperature of 15 ° C, 20 °, 30 ⁰ C or 40 ° C are processed without a substantial quality deterioration can be measured.

The dynamic viscosity of the coating agent is dependent on the solids content and the nature of the optionally usable solvent and can cover a wide range. So this can be more than 20,000 mPas at high polymer content. Expediently, a dynamic viscosity in the range from 10 to 10000 mPas, preferably 100 to 8000 mPas and very particularly preferably 1000 to 6000 mPas, measured according to DIN EN ISO 2555 at 25 ° C (Brookfield) is usually.

A surprisingly good processability, moreover, show coating compositions whose solids content is preferably at least 50% by weight, more preferably at least 60% by weight.

For a given solids content, the coating compositions of the invention can be processed over a much wider temperature range than previously known coating compositions. With comparable processing properties, the coating compositions of the invention are characterized by a surprisingly high solids content, so that the coating compositions of the invention are particularly environmentally friendly.

Furthermore, the present invention provides a process for producing a coating in which a coating composition according to the invention is applied to a substrate and cured.

The coating composition according to the invention can be applied by conventional application methods such as dipping, rolling, flooding, casting, in particular by brushing, rolling, spraying (high pressure, low pressure, airless or electrostatic (ESTA)). The curing of the coating agent is carried out by drying and by oxidative crosslinking by means of atmospheric oxygen. According to a particular aspect of the present invention, crosslinking with a crosslinking agent, in particular a polyisocyanate, can be carried out.

The substrates which can preferably be provided with a coating composition according to the invention include, in particular, metals, in particular iron and steel, zinc and galvanized steels, as well as plastics and concrete substrates. Moreover, the present invention provides coated articles obtainable by a method according to the invention. The coating of these objects is characterized by an excellent property spectrum.

Preferred coatings obtained from the coating compositions of the invention exhibit high mechanical resistance. The pendulum hardness is preferably at least 30 s, preferably at least 50 s and very particularly preferably at least 100 s, measured in accordance with DIN ISO 1522.

Furthermore, preferred coatings which are obtainable from the coating compositions of the invention have a surprisingly high adhesive strength, which can be determined in particular according to the cross-cut test. In particular, a classification of 0 to 1, particularly preferably 0, in accordance with the DIN EN ISO 2409 standard can be achieved.

The coatings obtainable from the coating compositions according to the invention generally exhibit high solvent resistance, with only small amounts in particular being dissolved out of the coating by solvents. Preferred coatings exhibit excellent resistance in particular to polar solvents, in particular alcohols, for example 2-propanol, or ketones, for example methyl ethyl ketone (MEK), nonpolar solvents, for example diesel fuel (alkanes). After an exposure of 15 minutes and subsequent drying (24 hours at room temperature), preferred coatings according to the present invention exhibit a pendulum hardness according to DIN ISO 1522 of at least 90 s, preferably 100 s. In addition, the coating compositions of the invention can be designed so that they show a high resistance to acids and bases. In addition, preferred coatings show a surprisingly good cupping. According to particular modifications of the present invention, coatings show a depression of at least 4.5 mm, more preferably at least 5 mm, measured according to DIN 53156 (Erichsen).

Hereinafter, the present invention will be explained with reference to examples and comparative examples, without thereby limiting it.

Preparation of a mixture of methacryloyloxy-2-ethyl-fatty acid amides (MUMA)

In a four-necked round bottom flask equipped with a saber stirrer with stirring sleeve and stirrer motor, nitrogen inlet, sump thermometer and a distillation bridge, 206.3 g (0.70 mol) of fatty acid methyl ester mixture, 42.8 g (0.70 mol) of ethanolamine and 0 , 27 g (0.26%) of LiOH presented. The fatty acid methyl ester mixture comprised 6% by weight of saturated C12 to C16 fatty acid methyl ester, 2.5% by weight of saturated C17 to C20 fatty acid methyl ester, 52% by weight of monounsaturated C18 fatty acid methyl ester, 1.5% by weight of monounsaturated C20 to C24 fatty acid methyl esters , 36% by weight of polyunsaturated C18 fatty acid methyl ester, 2% by weight of polyunsaturated C20 to C24 fatty acid methyl esters.

The reaction mixture was heated to 150 ⁰ C. Within 2 h, 19.5 ml of methanol were distilled off. The resulting reaction product contained 86.5% fatty acid ethanolamides. The resulting reaction mixture was further processed without purification.

After cooling, 1919 g (19.2 mol) of methyl methacrylate, 3.1 g of LiOH and an inhibitor mixture consisting of 500 ppm hydroquinone monomethyl ether and 500 ppm phenothiazine were added.

While stirring, the reaction apparatus was purged with nitrogen for 10 minutes. Thereafter, the reaction mixture was heated to boiling. The methyl methacrylate / methanol Azeotrope was separated and then the head temperature gradually increased to 100 ⁰ C. After completion of the reaction, the reaction mixture was cooled to about 70 ⁰ C and filtered.

Excess methyl methacrylate was separated on a rotary evaporator. It could be obtained 370 g of product.

example 1

In a reaction vessel, 50.01 g of solvent (Solvesso 100) were introduced and heated to 140 ° C. Oxygen in the reaction vessel was removed by introducing nitrogen. Subsequently, a reaction mixture comprising 15.33 g of di-tert-butyl peroxide (DTBP), 41.15 g of isobornyl methacrylate (IBOMA), 61. 73 hydroxyethyl methacrylate (HEMA), 20.58 g of ethylhexyl methacrylate (EHMA), 20.58 g Methacryloy- loxy-2-ethyl fatty acid amide (MUMA), 61, 73 g of styrene and 3.69 g of 2-mercaptoethanol were added over a period of 4 hours. Subsequently, the reaction was continued for 30 minutes with stirring. Thereafter, the mixture was cooled to 80 ⁰ C. To complete the reaction, a mixture comprising 0.21 g of di-tert-butyl peroxide (DTBP) and 15 g of solvent (Solvesso 100) was added, followed by stirring at 80 ° C. for a further 2 hours. The mixture was then further stirred for 30 minutes without heating.

The polymer content was adjusted to 65% by adding 46.16 g of n-butyl acetate.

The properties of the coating agent thus obtained were examined. For this purpose, a film having a thickness of about 50 microns was formed on an aluminum plate, wherein the polymer film by addition of polyisocyanate (hexamethylene diisocyanate, HDI 50/60 NCO / OH) and dibutyltin dilaurate (DBTL, 0.01 wt .-%, based on the Polymer weight) was crosslinked. The hardness or scratch resistance of the crosslinked polymer film was examined by determining the pendulum hardness. The chemical resistance was examined by treating the polymer film with methyl ethyl ketone. Subsequently, the pendulum hardness of the film was measured. The criterion used here is in particular a softening of the film by the treatment with the solvent. The brittleness of the film was examined by creep tests according to Erichsen. Furthermore, the adhesive strength of the coating was determined by a crosshatch test.

The results obtained are shown in Table 1.

Comparative Example 1

In a reaction vessel, 100.02 g solvent (Solvesso 100) were placed and heated to 140 ⁰ C. Oxygen in the reaction vessel was removed by introducing nitrogen. Subsequently, a reaction mixture comprising 30.66 g of di-tert-butyl peroxide (DTBP), 82.31 g of isobornyl methacrylate (IBOMA), 123.46 hydroxyethyl methacrylate (HEMA), 82.31 g of ethylhexyl methacrylate (EHMA), 123.46 g of styrene and 7.38 g of 2-mercaptoethanol were added over a period of 4 hours. Subsequently, the reaction was continued for 30 minutes with stirring. Thereafter, the mixture was cooled to 80 ⁰ C. To complete the reaction, a mixture comprising 0.42 g of di-tert-butyl peroxide (DTBP) and 10 g of solvent (Solvesso 100) was added, followed by stirring for a further 2 hours at 80 ° C. Subsequently, another 40 g of solvent (Solvesso 100) were added, with stirring for 30 minutes without heating.

The polymer content was adjusted to 65% by adding 92.31 g of n-butyl acetate.

From the obtained coating agent, a film was prepared according to the method set forth in Example 1. The properties of the coatings obtained were determined with the examination methods set out above, the results obtained are shown in Table 1. Table 1: Properties of the investigated coating compositions

The examples presented above show that the coatings consistently have a very good pendulum hardness, good adhesion and a relatively low brittleness (cupping test).

Surprisingly, the (meth) acrylate polymers according to the invention having a content of MUMA show a somewhat higher pendulum hardness, although the number of carbon atoms in the alkyl radical of the methacrylate is markedly greater than in EHMA. It is of particular interest that the brittleness decreases. Furthermore, the (meth) acrylate polymers containing MUMA show a significantly increased solvent resistance to polar solvents.

Claims

claims

1. (meth) acrylate polymer for preparing a coating composition, characterized in that the (meth) acrylate polymer 0.5 to 20 wt .-% of units derived from (meth) acrylic monomers which in the alkyl radical at least have a double bond and 8 to 40 carbon atoms,

0.1 to 60% by weight of units derived from hydroxyl-containing monomers having up to 9 carbon atoms, 0.1 to 95% by weight of units derived from (meth) acrylates having 1 to 12 carbon atoms are derived in the alkyl radical, and

0.1 to 60% by weight of units derived from styrene monomers, each based on the weight of the (meth) acrylate polymer, and the (meth) acrylate polymer has a weight average molecular weight in the range of 2000 to 60000 g / mol.

2. (meth) acrylate polymer according to claim 1, characterized in that the weight ratio of units derived from hydroxyl-containing monomers, to the units derived from (meth) acrylic monomers which in the alkyl radical at least one Have double bond and 8 to 40 carbon atoms, greater than 1.

3. (meth) acrylate polymer according to claim 1 or 2, characterized in that the (meth) acrylate polymer comprises units which are derived from (meth) acrylates having a hydroxy group in the alkyl radical, preferably from 2

Hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate and / or 3-hydroxypropyl (meth) acrylate.

4 (meth) acrylate polymer according to one of the preceding claims, characterized in that (meth) acrylate polymer 5 to 40 wt .-% of units derived from cycloalkyl (meth) acrylates.

5. Meth) acrylate polymer according to claim 4, characterized in that the (meth) acrylate polymer

Comprising units derived from cyclohexyl methacrylate and / or isobornyl methacrylate.

6. Meth) acrylate polymer according to one of the preceding claims, character- ized in that (meth) acrylate polymer has a glass transition temperature in the range of 20 to 90 ⁰ C.

7. Meth) acrylate polymer according to one of the preceding claims, characterized in that the (meth) acrylate polymer has a weight-average molecular weight in the range of 4000 g / mol to 40,000 g / mol.

8. Meth) acrylate polymer according to one of the preceding claims, characterized in that the (meth) acrylate polymer has a polydispersity index M _w / M _n in the range of 1 to 5.

9. Meth) acrylate polymer according to one of the preceding claims, characterized in that the (meth) acrylate polymer has an iodine value in the range of 5 to 100 g of iodine per 100 g of polymer.

10. Meth) acrylate polymer according to one of the preceding claims, characterized in that the (meth) acrylate polymer has a hydroxyl number in the range of 3 to 300 mg KOH / g.

11. Coating composition, characterized in that the coating composition comprises 40 to 80% by weight of at least one polymer according to claims 1 to 10.

12. A coating composition according to claim 11, characterized in that the solids content is at least 50 wt .-%.

13. Coating composition according to claim 11 or 12, characterized in that the coating composition comprises at least one crosslinking agent.

14. A coating composition according to claim 13, characterized in that the crosslinking agent comprises or releases a polyisocyanate.

A coating composition according to claim 13 or 14, characterized in that the coating composition comprises from 0.5 to 10% by weight of crosslinking agent.

16. A process for producing a coating, characterized in that a coating composition according to claim 14 or 15 is applied to a substrate and cured.

17. The method according to claim 16, characterized in that the substrate is made of metal.

18. A coated article obtainable by a process according to claim 16 or 17.