EP3684834A1

EP3684834A1 - Polyaspartic acid ester compositions which contain polyaspartic acid esters with primary amino groups and small amounts of fumaric acid dialkyl esters

Info

Publication number: EP3684834A1
Application number: EP18768894.0A
Authority: EP
Inventors: Dorota Greszta-Franz; Jan Weikard; Matthias Wintermantel; Robert Maleika; Thomas Klimmasch; Thomas SCHÜTTLER
Original assignee: Covestro Deutschland AG
Current assignee: Covestro Deutschland AG
Priority date: 2017-09-19
Filing date: 2018-09-14
Publication date: 2020-07-29
Also published as: JP7451398B2; KR20200056387A; CN111065668B; US20200216383A1; EP3456755A1; US11230522B2; JP2020534297A; CN111065668A; WO2019057626A1

Abstract

The present invention relates to polyaspartic acid ester compositions which contain polyaspartic acid esters with primary amino groups and small amounts of fumaric acid dialkyl esters, to a method for preparing same and the use thereof as a reactive component for polyisocyanates in two-component polyurethane systems.

Description

Polyaspartic acid ester compositions comprising polyaspartic acid esters with primary amino groups and small amounts of dialkyl fumarate

The present invention relates to polyaspraginate ester compositions comprising polyaspartic acid esters having primary amino groups and small amounts of dialkyl fumarates, a process for their preparation and their use as reactive components for polyisocyanates in two-component polyurethane systems.

Two-component (2K) coating compositions containing as binder a polyisocyanate component in combination with a reactive isocyanate-reactive component, in particular a polyhydroxyl component, have long been known. They are suitable for the production of high-quality coatings that can be adjusted to be hard, elastic, resistant to abrasion and solvents and, above all, to be weather-resistant.

Within this two-pack polyurethane coating technology, certain ester-containing secondary polyamines have recently become established which, in combination with lacquer polyisocyanates, are particularly suitable as binders in low-solids or high-solids coatings and enable rapid curing of the coatings at low temperatures , These secondary polyamines are the so-called polyaspartic esters, as described by way of example in EP0403921. Their use alone or in admixture with further components which are reactive toward isocyanate groups in 2K polyurethane coating compositions is described, for example, in EP0403921, EP0639628, EP0667362, EP0689881, US5214086, EP0699696, EP0596360, EP0893458, DE19701835 and US5243012.

The synthesis of the polyaspartic acid esters is known per se and takes place via an addition of primary polyamines to an activated carbon double bond vinylogous carbonyl compounds, as for example in Malein- or fumaric acid esters, which is adequately described in the literature (Weyl, Weber, Meth Chem., Vol. 11/1, 272 (1957), Usp. Khim., 1969, 38, 1933). In this reaction, a polyaspartic acid ester having primary amino groups may be by-produced if only one amino group of the polyamine has reacted with the double bond of the vinylogous carbonyl compounds. In the commercially available polyaspartic esters, maleic acid ester is used as the vinylogous carbonyl compound. During the preparation of a polyaspartic acid ester based on maleic acid ester, a retro-Michael addition may be another undesirable Side reaction occur in which is formed by elimination of the polyamine as a minor component Fumarsäuredialkylester. A typical production process of a polyaspartic acid ester therefore requires a storage time of 4-6 weeks after the majority of the starting materials have reacted with one another. During this time, the so-called maturation of the product, which manifests itself by stabilizing the viscosity occurs. Due to the fact that the turnover continues to increase within this time, the content of dialkyl fumarate also decreases. This storage over several weeks leads to significant logistics costs within the production. Although the product is shipped to the customer after storage, it still contains substantial amounts of dialkyl fumarate which can cause severe sensitization. Fumaric acid diethyl ester is classified, for example, as VOC (volatile organic compounds) and thus prevents the provision of VOC-free coatings. Another disadvantage caused by the presence of dialkyl fumarate is the lowering of the glass transition temperature of a paint film by its softening effect. Because of the above-described disadvantages of polyaspartic acid ester compositions and their preparation heretofore, there has long been a demand for low fumarate dialkyl ester polyaspartic acid ester compositions which can be prepared by a process which requires no or a reduced maturation time. There are theoretically two ways to change the process for the preparation of polyaspartic acid ester compositions, so that Polyasparaginsäureester- arise compositions that do not have the disadvantages mentioned above. The reaction time can be extended or the reaction temperature can be increased. The former leaves for economic reasons. An increase in the reaction temperature to eg 100 ° C or even to 80 ° C in turn leads to a dramatic yellowing of the product.

EP0816326 discloses a process for accelerating the addition of the polyamine to dialkyl maleate or reducing the fumaric acid dialkyl ester by the addition of a specific catalyst. Since, despite the use of a catalyst, the need for storage can not be prevented, this approach does not lead to the final satisfactory result. EP 1197507 describes the addition of thiol compounds as scavengers for dialkyl fumarates. Due to the fact that the thiol compounds are known to cause considerable odor nuisance, this solution can not be converted into practice. A theoretical possibility of distillative work-up is mentioned, for example, in EP0403921. It is a distillative removal of dialkyl fumarate within a process in which an excess of dialkyl maleate is used. This revelation gives no examples and no method for distillation. Since an excess of diethylmaleinate is used in this process, it is not to be expected that the worked-up product will have significant amounts of polyaspartic acid esters with primary amino groups. This method has not been successful because the excess amount of diethyl maleate used results in poor time-space yield and waste, which is economically unacceptable.

DE102006002153 likewise describes a product which is prepared using an excess of dialkyl maleate and subsequent removal by distillation of dialkyl fumarate. It is a diaspartic ester which is free of primary amino groups.

The preparation of amino-functional aspartic acid esters is known in principle. WO15130501 and WO15130502 disclose polyaspartic acid ester compositions which have between 15 and 30% aspartic acid ester with primary amino groups (measured as area% in the gas chromatogram). In both documents, however, no advantage due to an increased content of aspartic acid esters with primary amino groups is recognized and polyaspartic acid ester compositions with acceptable pot life could only be achieved by further reaction with preferably cycloaliphatic polyisocyanates. It is to be understood that the coating compositions thus prepared do not have a reduced content of diethyl fumarate due to the conventional production process.

In the context of the present invention, polyaspartic ester compositions may be produced which have a content of 1% to 20% of polyaspartic acid ester with primary amino groups (measured as area% in the gas chromatogram) and a reduced content of 0.01% by weight to 3% by weight. Having percent of Fumarsäuredialkylester while overcoming the known in the prior art disadvantages of Polyasparaginsäureester compositions. These compositions of the invention could be prepared by a process with and without a storage process. It has been found that thin film distillation of a non-ripened polyaspartic ester composition (ie, immediately after production) results in a product having levels of fumaric acid dialkyl ester below 1%. Since the reaction conversion at the time of the thin-film distillation is about 90%, the product contains a significantly increased proportion of polyaspartic acid ester with primary amino groups compared to the conventional polyaspartic acid ester composition. As expected, the high proportion of polyaspartic esters with primary amino groups could lead to a shorter pot life. Surprisingly, however, it was found that the pot life of the invention Polyaspartic ester compositions do not differ from the pot life of a conventionally prepared polyaspartic ester composition. Moreover, the polyaspartic ester compositions of the present invention have accelerated drying and improved condensed water resistance as further technical advantages. The process of thin film distillation can also be applied to ripened polyaspartic ester compositions. In this case, the advantage is not the lack of maturation, but the reduced amount of dialkyl fumarate and faster drying due to the increased proportion of polyaspartic acid ester with primary amino group.

The present invention relates to a composition comprising one or more polyaspartic esters of the general formula (I)

in which

X is an m-valent organic radical optionally containing one or more heteroatoms, as obtained by removal of the primary amino groups from a corresponding, (cyclo) aliphatically or araliphatically bonded primary amino groups containing polyamine in the molecular weight range 60 to 6000 g / mol can contain, and the other, opposite isocyanate-reactive and / or inert at temperatures up to 100 ° C functional groups,

R 1 and R 2 represent identical or different organic radicals, each having 1 to 18

Carbon atoms, m is an integer> 1,

and

one or more polyaspartic acid esters with primary amino group of the general formula (II)

in which

n stands for m-1,

X, radicals Rl and R2 have the abovementioned meanings, characterized in that the proportion of the compound of the general formula (II) from 1% to 20% of the GC surface (measured as area% in the gas chromatogram), corresponds to Sum of the GC surfaces of the two compounds of the general formula (I) and (II) is 100% and a proportion of Fumarsäuredialkylester of 0.01 to 3 wt. Percent is present.

The polyaspartic ester compositions according to the invention are preferred in which R 1 and R 2 are identical or different alkyl radicals each having 1 to 18 carbon atoms, preferably identical or different alkyl radicals having 1 to 8 carbon atoms and very particularly preferably each alkyl radicals such as methyl, ethyl, propyl -, iso-propyl, butyl or iso-butyl radicals. Most preferred is ethyl.

Polyaspartic acid ester compositions according to the invention are those in which X represents organic radicals obtained by removal of the primary amino groups from a corresponding (cyclo) aliphatically or araliphatically bonded primary amino-containing polyamine selected from the following group: all known polyamines primary amino groups corresponding to the general formula (III). Examples include the following compounds: ethylenediamine, 1,2-diaminopropane, 1,4-diaminobutane, 1,5-diaminopentane, 2,5-diamino-2,5-dimethylhexane, l, 5-diamino-2-methylpentane (Dytek ®A, Fa DuPont), 1,6-diaminohexane, 2,2,4- and / or 2,4,4-trimethyl-l, 6-diaminohexane, 1,11-diaminoundecane, 1,12-diaminododecane or triaminononane, Etheramine, such as 4,9-dioxadodecane-l, 12-diamine, 4,7,10-trioxatridecane- 1, 13 -diamine, or higher molecular weight polyether polyamines having aliphatically bonded, primary amino groups, as described for example under the name Jeffamine® of the Company Huntsman be distributed. It is also possible to use aliphatic polycyclic polyamines, such as tricyclodecanebismethylamine (TCD-diamine) or bis (aminomethyl) norbornane, amino-functional siloxanes, for example diaminopropylsiloxane G10 DAS (from Momentive), fatty-alkyl-based amines, for example Fentamine from Solvay, dimer fatty acid diamines such as Priamine Fa. Croda. Preferred polyaspartic acid ester compositions according to the invention are those in which X represents organic radicals obtained by removal of the primary amino groups from one of the polyamines of the general formula (III) in which m = 2 and X is a cyclic hydrocarbon radical containing at least one cyclic carbon ring stands. Examples of particularly preferably usable diamines are l-amino-3,3,5-trimethyl-5-aminomethylcyclohexane (IPDA), 2,4- and / or 2,6-hexahydrotoluylenediamine (H6-TDA), isopropyl-2,4 diaminocyclohexane, and / or isopropyl-2,6-diaminocyclohexane, 1,3-bis (aminomethyl) -cyclohexane, 2,4'-, and / or 4,4'-diamino-dicyclohexylmethane, 3,3'-dimethyne 4,4'-diamino-dicyclohexylmethane (Laromin® C 260, BASF AG), the isomeric, having a methyl group as a core substituent diaminodicyclohexylmethane (= C-monomethyl-diaminodicyclohexylmethane), 3 (4) -aminomethyl-l-methylcyclohexylamin (AMCA ) and araliphatic diamines, such as l, 3-bis (aminomethyl) benzene or m-xylylenediamine.

Likewise preferred are the polyaspartic ester compositions of the invention in which X represents organic radicals obtained by removal of the primary amino groups from one of the polyamines of the general formula (III) selected from the group consisting of polyether polyamines having aliphatically bonded primary amino groups, 1,2 Diaminopropane, 1,4-diaminobutane, 1,6-diaminohexane, 1, 5-diamino-2-methylpentane, 2.5 diamino-2,5-dimethylhexane, 2,2,4- and / or 2,4,4- Trimethyl-l, 6-diaminohexane, 1,11-diaminounodecane, 1,12-diaminododecane, 1-amino-3,3,5-trimethyl-5-aminomethylcyclohexane, 2,4- and / or 2,6-hexahydrotoluenediamine, 1 , 5-diaminopentane, 2,4'- and / or 4,4'-diamino-dicyclohexylmethane or 3,3'-dimethyl-4,4'-diamino-dicyclohexylmethane. Particularly preferred are 3,3'-dimethyl-4,4'-diamino-dicyclohexylmethane, 1,5-diaminopentane, 2,4'- and / or 4,4'-diaminodicyclohexylmethane, 1,5-diamino-2-methylpentane and very particular preference is given to the use of 2,4'- and / or 4,4'-diaminodicyclohexylmethane.

Particularly preferred polyaspartic acid ester compositions according to the invention are those in which X represents organic radicals obtained by removing the primary amino groups from one of the polyamines of general formula (III) selected from the group consisting of polyether polyamines having aliphatically bonded primary amino groups, 1,2 Diaminopropane, 1,4-diaminobutane, 1,5-diaminopentane, 1,6-diaminohexane, 1,5-diamino-2-methylpentane, 2,5-diamino-2,5-dimethylhexane, 2,2,4- and / or 2,4,4-trimethyl-l, 6-diaminohexane, 1,11-diaminounodecane, 1,12-diaminododecane, 1-amino-3,3,5-trimethyl-5-aminomethylcyclohexane, 2,4- and / or 2 , 6-hexahydrotoluenediamine, 2,4'- and / or 4,4'-diamino-dicyclohexylmethane or 3,3'-dimethyl-4,4'-diaminodicyclohexylmethane.

Very particular preference is given to the polyaspartic ester compositions according to the invention in which X represents organic radicals which are obtained by removal of the primary amino groups from one of the polyamines of the general formula (III) from the group: 3,3'-dimethyl-4,4-iaminodicyclohexylmefhan, 2,4'- and / or 4,4'-diaminodicyclohexylmethane, 1, 5-diamino-2-methylpentane.

Preferably, m is an integer> 1 and preferably 2.

The polyaspartic ester compositions according to the invention preferably contain from 1% to 20%, preferably from 4% to 20%, more preferably from 4% to 15%, of the GC surface area (measured as area% in the gas chromatogram) of the compound of the general formula (cf. II), wherein the sum of the GC surfaces of the two compounds of the general formula (I) and (II) is 100%.

Preference is given to the inventive polyaspartic ester compositions containing from 0.01 to 3% by weight, preferably from 0.01 to 1% by weight, particularly preferably from 0.01 to 0.1% by weight, of dialkyl fumarate.

Likewise preferred are the inventive polyaspartic ester compositions containing from 0.01 to 0.99 percent by weight of dialkyl fumarate.

A particularly preferred subject of the present invention is a composition comprising one or more polyaspartic esters of the general formula (I),

in which

X is an m-valent organic radical optionally containing one or more heteroatoms, as obtained by removal of primary amino groups from polyetherpolyamines having aliphatically bonded primary amino groups, 1,2-diaminopropane, 1,4-diaminobutane, 1,5-

Diaminopentane, 1,6-diaminohexane, l, 5-diamino-2-methylpentane, 2,5-diamino-2,5-dimethylhexane, 2,2,4- and / or 2,4,4-trimethyl-l, 6- diaminohexane, 1,11-diaminounodecane, 1,12-diaminododecane, 1-amino-3,3,5-trimethyl-5-aminomethylcyclohexane, 2,4- and / or 2,6-hexahydrotoluylenediamine, 2,4'- and / or or 4,4'-diamino-dicyclohexylmethane or 3,3'-dimethyl-4,4'-diaminodicyclohexylmethane is obtained,

R 1 and R 2 represent identical or different alkyl radicals each having 1 to 8 carbon atoms,

m stands for an integer> 1,

and one or more polyaspartic acid esters with primary amino group of the general formula (II),

in which

n stands for m-1,

X, radicals Rl and R2 have the abovementioned meanings, characterized in that the proportion of the compound of the general formula (II) of 4% to 20% of the GC surface area (measured as area% in the gas chromatogram), corresponds to Sum of the GC surfaces of the two compounds of the general formula (I) and (II) is 100% and a proportion of Fumarsäuredialkylester of 0.01 to 1 wt. Percent is present.

A very particularly preferred subject matter of the present invention is a composition comprising one or more polyaspartic esters of the general formula (I),

in which

X is an m-valent organic radical, as obtained by removal of primary amino groups from 3,3'-dimethyne

4,4'diaminodicyclohexylmethane, 2,4'- and / or 4,4'-

Diaminodicyclohexylmethane, l, 5-diamino-2-methylpentane can be obtained

R 1 and R 2 represent identical or different alkyl radicals selected from the group

Methyl, ethyl, propyl, iso-propyl, butyl or iso-butyl radicals, m is 2,

and

one or more polyaspartic acid esters with primary amino group of the general formula (II),

in which

n stands for m-1,

X, radicals Rl and R2 have the abovementioned meanings, characterized in that the proportion of the compound of the general formula (II) of 4% to 15% of the GC surface area (measured as area% in the gas chromatogram), corresponds to Sum of the GC surfaces of the two compounds of the general formula (I) and (II) is 100% and a proportion of Fumarsäuredialkylester 0.01 to 0.1 wt. Percent is present.

Another particularly preferred subject matter of the present invention is a composition comprising one or more polyaspartic esters of the general formula (I), in which

X is an m-valent organic radical, as can be obtained by removal of primary amino groups from 3,3'-dimethyl-4,4'diaminodicyclohexylmethane, 2,4'- and / or 4,4'-diaminodicyclohexylmethane .

R 1 and R 2 are ethyl radicals,

m stands for 2,

and

in which

n stands for m-1,

X, radicals Rl and R2 have the abovementioned meanings, characterized in that the proportion of the compound of the general formula (II) of 4% to 15% of the GC surface (measured as area% in the gas chromatogram), the proportion of the two Compounds of the general formula (I) and (II) corresponds, wherein the sum of the GC surfaces of the two compounds of the general formula (I) and (II) is 100% and a proportion of Fumarsäuredialkylester 0.01 to 0.1 percent by weight.

A further particularly preferred subject matter of the present invention is a composition comprising one or more polyaspartic esters of the general formula (I)

m

(I)

in which

X is an m-valent organic radical optionally containing one or more heteroatoms, as obtained by removal of the primary amino groups from a corresponding, (cyclo) aliphatically or araliphatically bonded primary amino groups containing polyamine in the molecular weight range 60 to 6000 g / mol can contain, and the other, opposite isocyanate-reactive and / or inert at temperatures up to 100 ° C functional groups, R 1 and R 2 represent identical or different organic radicals, each having 1 to 18

Carbon atoms, m is an integer> 1,

and

in which

n stands for m-1,

X, radicals Rl and R2 have the abovementioned meanings, characterized in that the proportion of the compound of the general formula (II) of 4% to 15% of the GC surface area (measured as area% in the gas chromatogram), corresponds to

Sum of the GC surfaces of the two compounds of the general formula (I) and (II) is 100% and a proportion of Fumarsäuredialkylester of 0.01 to 1 wt. Percent is present.

m

(I)

in which

X is an m-valent, optionally containing one or more heteroatoms organic radical, such as by removal of the primary amino groups from a corresponding, (cyclo) aliphatic or araliphatic bound primary amino groups containing polyamine the molecular weight range 60 to 6000 g / mol can be obtained, and the other, reactive to isocyanate groups and / or may contain at temperatures up to 100 ° C inert functional groups,

Carbon atoms, m is an integer> 1,

and

in which

n stands for m-1,

X, radicals Rl and R2 have the abovementioned meanings, characterized in that the proportion of the compound of the general formula (II) of 4% to 15% of the GC surface (measured as area% in the gas chromatogram), the proportion of the two Compounds of the general formula (I) and (II) corresponds, wherein the sum of the GC surfaces of the two compounds of the general formula (I) and (II) is 100% and a proportion of Fumarsäuredialkylester of 0.01 to 0.99 percent by weight.

Preference is given to polyaspartic acid ester compositions according to the invention which have a platinum cobalt color number <100, particularly preferably <50. The measurement of the platinum-cobalt color number is carried out in accordance with DIN EN ISO 6271: 2016-05.

The invention further provides a process for the preparation of the composition comprising one or more polyaspartic esters of the general formula (I)

in which

R 1 and R 2 represent identical or different organic radicals, preferably identical or different alkyl radicals each having 1 to 18 carbon atoms, and very particularly preferably identical or different alkyl radicals each having 1 to 8 carbon atoms, m is an integer> 1,

and

in which

n stands for m-1,

X, radicals R 1 and R 2 have the abovementioned meanings, prepared by reacting polyamines of the general formula (III),

(III)

where X and m have the abovementioned meaning, with compounds of the general formula (IV)

R1 OOC- C H = C H- COOR2

(IV),

where the radicals R 1 and R 2 have the abovementioned meaning, and a distillative removal of the unreacted fraction of the compound of the general formula (IV),

characterized in that the resulting polyaspartic ester composition comprises a proportion of the compound of the general formula (II) of from 1% to 20% of the GC surface (measured as area% in the gas chromatogram) equal to the proportion of both compounds of the general formula (I ) and (II), wherein the sum of the GC surfaces of the two compounds of the general formula (I) and (II) is 100% and contains a proportion of fumaric acid dialkyl ester of 0.01 to 3 wt. Percent.

Another preferred subject of the present invention is the process disclosed above for the preparation of the composition comprising one or more polyaspartic esters of the general formula (I) in which

X is an m-valent organic radical optionally containing one or more heteroatoms, as obtained by removal of primary amino groups from polyether polyamines having aliphatically bonded primary amino groups, 1,2-diaminopropane, 1,4-diaminobutane, 1,5-diaminopentane, 1 , 6-diaminohexane, 1, 5-diamino-2-methylpentane, 2.5 diamino-2,5-dimethylhexane, 2,2,4- and / or 2,4,4-trimethyl-1,6-diaminohexane, 1 , 11-diaminounodecane, 1,12-diaminododecane, 1-amino-3,3,5-trimethyl-5-aminomethylcyclohexane, 2,4- and / or 2,6-hexahydrotoluylenediamine, 2,4'- and / or 4, 4'-diamino-dicyclohexylmethane or 3,3'-dimethyl-4,4'-diaminodicyclohexylmethane is obtained,

R 1 and R 2 represent identical or different alkyl radicals each having 1 to 8 carbon atoms, m stands for an integer> 1,

and

in which

n stands for m-1,

X, radicals Rl and R2 have the abovementioned meanings, prepared by reacting polyamines of the general formula (III), wherein X and m have the abovementioned meaning, with compounds of the general formula (IV), wherein the radicals Rl and R2 have the abovementioned meaning, and a distillative removal of the unreacted portion of the compound of the general formula (IV), characterized in that the resulting polyaspartic ester composition has a proportion of the compound of the general formula (II) of 4% to 20% of GC surface area (measured as area% in the gas chromatogram), which corresponds to the proportion of the two compounds of the general formula (I) and (II), wherein the sum of the GC surfaces of the two compounds of the general formula (I) and (II) 100 % and contains a proportion of dialkyl fumarate of 0.01 to 1 wt. Percent.

X is an m-valent organic radical, as obtained by removal of primary amino groups from 3,3'-dimethyl-4,4'-diamino-dicyclohexylmethane, 2,4'- and / or 4,4'-diamino-dicyclohexylmethane, l, 5-diamino-2-methylpentane can be obtained, Rl and R2 are the same or different alkyl radicals selected from the group

Methyl, ethyl, propyl, iso-propyl, butyl or iso-butyl radicals, m is 2,

and

one or more polyaspartic acid esters with primary amino group of the general formula (II), in which

n stands for m-1,

X, radicals R 1 and R 2 have the abovementioned meanings, prepared by reacting polyamines of general formula (III), wherein X and m have the abovementioned meaning, with compounds of general formula (IV), wherein the radicals Rl and R2 have the abovementioned meaning, and a distillative removal of the unreacted A proportion of the compound of the general formula (IV), characterized in that the resulting polyaspartic ester composition has a proportion of the compound of the general formula (II) of 4% to 15% of the GC surface (measured as area% in the gas chromatogram) which corresponds to the proportion of the two compounds of the general formula (I) and (II), wherein the sum of the GC surfaces of the two compounds of the general formula (I) and (II) is 100% and a proportion of fumaric acid dialkyl 0.01 to 0.1 wt . Percent contains.

Another preferred subject matter of the invention is a process for the preparation of the composition comprising one or more polyaspartic esters of the general formula (I)

m

(I)

in which

R1 and R2 represent identical or different organic radicals, preferably identical or different alkyl radicals each having 1 to 18 carbon atoms, and very particularly preferably identical or different alkyl radicals each having 1 to 8

Carbon atoms, m stands for an integer> 1,

and

(II)

in which

n stands for m-1,

X, radicals R 1 and R 2 have the abovementioned meanings, prepared by reaction of polyamines of the general formula (III),

(III)

R1 OOC- C H = C H- COOR2

(IV),

wherein the radicals R 1 and R 2 have the abovementioned meaning, and a distillative removal of the unreacted fraction of the compound of the general formula (IV), characterized in that the resulting polyaspartic ester composition comprises a proportion of the compound of the general formula (II) from 4% to 15% of the GC surface area (measured as area% in the gas chromatogram), which corresponds to the proportion of both compounds of the general formula (I) and (II), the sum of the GC surfaces of the two compounds of the general formula ( I) and (II) is 100% and contains a proportion of dialkyl fumarate of 0.01 to 1 wt. Percent. Another preferred subject matter of the invention is a process for the preparation of the composition comprising one or more polyaspartic esters of the general formula (I)

m

(I)

in which

X is an m-valent organic radical optionally containing one or more heteroatoms, as obtained by removal of the primary amino groups from a corresponding, (cyclo) aliphatically or araliphatically bonded primary amino groups containing polyamine in the molecular weight range 60 to 6000 g / mol can contain, and the further, isocyanate-reactive and / or inert at temperatures up to 100 ° C functional groups,

and

n

(II)

in which

n stands for m-1,

(III),

R1 OOC- C H = C H- COOR2

(IV),

wherein the radicals Rl and R2 have the abovementioned meaning, and a distillative removal of the unreacted portion of the compound of the general formula (IV), characterized in that the resulting polyaspartic ester composition comprises a proportion of the compound of the general formula (II) of 4% to 15% of the GC surface area (measured as area% in the gas chromatogram), the sum of the GC surfaces of the two compounds of the general formula (I) and (II) being 100% and a fraction of fumaric acid dialkyl ester of 0.01 to 0.99 weight percent.

X is an m-valent organic radical, such as can be obtained by removal of primary amino groups from 2,4 and / or 4,4'-

Diaminodicyclohexylmethan can be obtained, Rl and R2 are ethyl radicals,

m stands for 2,

and

in which

n stands for m-1,

X, radicals Rl and R2 have the abovementioned meanings, prepared by reacting polyamines of the general formula (III), wherein X and m have the abovementioned meaning, with compounds of the general formula (IV), wherein the radicals Rl and R2 have the abovementioned meaning, and a distillative removal of the unreacted portion of the compound of general formula (IV), characterized in that the resulting polyaspartic ester composition has a proportion of the compound of general formula (II) of 4% to 15% of GC surface area (measured as area% in the gas chromatogram), where the sum of the GC surfaces of the two compounds of the general formula (I) and (II) is 100% and contains 0.01 to 0.1% by weight of a dialkyl fumarate ester ,

A further subject of the present invention is a composition comprising one or more polyaspartic esters of the general formula (I)

m

(I)

in which X is an m-valent organic radical optionally containing one or more heteroatoms, as obtained by removal of the primary amino groups from a corresponding, (cyclo) aliphatically or araliphatically bonded primary amino groups containing polyamine in the molecular weight range 60 to 6000 g / mol can contain, and the other, opposite isocyanate-reactive and / or inert at temperatures up to 100 ° C functional groups,

Carbon atoms, m is an integer> 1,

and

n

(II)

in which

n stands for m-1,

X, radicals Rl and R2 have the abovementioned meanings, characterized in that the proportion of the compound of general formula (II) of 1% to 20% of the GC surface (measured as area% in the gas chromatogram), the proportion of the two Compounds of the general formula (I) and (II) corresponds, wherein the sum of the GC surfaces of the two compounds of the general formula (I) and (II) is 100% and a proportion of Fumarsäuredialkylester of 0.01 to 3 wt. Percent is present.

Preference is given to the polyaspartic ester compositions according to the invention containing from 1% to 20%, preferably from 4% to 20%, more preferably from 4% to 15% of the GC surface area (measured as area% in the gas chromatogram) of the two compounds of the general formula Formula (I) and (II), wherein the sum of the GC surfaces of the two compounds of the general formula (I) and (II) is 100%. A particularly preferred and further subject matter of the present invention is a composition comprising one or more polyaspartic esters of the general formula

(I),

in which

m stands for an integer> 1,

and

one or more polyaspartic acid esters with primary amino group of the general formula

(II),

in which

n stands for m-1,

X, radicals Rl and R2 have the abovementioned meanings, characterized in that the proportion of the compound of the general formula (II) of 4% to 20% of the GC surface (measured as area% in the gas chromatogram), the proportion of the two Compounds of the general formula (I) and (II) corresponds, wherein the sum of the GC surfaces of the two compounds of the general formula (I) and (II) is 100% and a proportion of Fumarsäuredialkylester of 0.01 to 1 percent by weight.

A very particularly preferred and further subject of the present invention is a composition comprising one or more polyaspartic esters of the general formula (I),

in which

X is an m-valent organic radical as obtained by removal of primary amino groups from 3,3'-dimethyl 4,4'diaminodicyclohexylmethane, 2,4'- and / or 4,4'-

Diaminodicyclohexylmethane, l, 5-diamino-2-methylpentane can be obtained

Methyl, ethyl, propyl, iso-propyl, butyl or iso-butyl radicals, m is 2,

and

in which

n stands for m-1,

X, radicals Rl and R2 have the abovementioned meanings, characterized in that the proportion of the compound of the general formula (II) of 4% to 15% of the GC surface (measured as area% in the gas chromatogram), the proportion of the two

Compounds of the general formula (I) and (II) corresponds, wherein the sum of the GC surfaces of the two compounds of the general formula (I) and (II) is 100% and a proportion of Fumarsäuredialkylester 0.01 to 0.1 percent by weight. Another particularly preferred subject of the present invention is a composition containing one or more polyaspartic esters of the general formula

(I),

in which

R 1 and R 2 are ethyl radicals,

m stands for 2,

and

(II),

in which

n stands for m-1,

X, radicals R 1 and R 2 have the abovementioned meanings, characterized in that the proportion of the compound of the general formula (II) from 4% to 15% of the GC surface area (measured as area% in the gas chromatogram), the proportion of the two compounds of the general formula (I) and (II) , Wherein the sum of the GC surfaces of the two compounds of general formula (I) and (II) is 100% and a proportion of Fumarsäuredialkylester 0.01 to 0.1 wt. Percent is present.

in which

and

(Π)

in which

n stands for m-1,

(III)

R1 OOC- C H = C H- COOR2

(IV),

where the radicals R 1 and R 2 have the abovementioned meaning, characterized in that the resulting polyaspartic ester composition has a proportion of the compound of the general formula (II) of from 1% to 20% of the GC surface (measured as area% in the gas chromatogram ), which corresponds to the proportion of two compounds of general formula (I) and (II), wherein the sum of the GC surfaces of the two compounds of general formula (I) and (II) is 100% and a proportion of Fumarsäuredialkylester from 0.01 to 3 Contains weight percent.

X is an m-valent organic radical optionally containing one or more heteroatoms, as obtained by removal of primary amino groups from polyether polyamines having aliphatically bonded primary amino groups, 1,2-diaminopropane, 1,4-diaminobutane, 1,5-diaminopentane, 1 , 6-diaminohexane, 1, 5-diamino-2-methylpentane, 2.5 Diamino-2,5-dimethylhexane, 2,2,4- and / or 2,4,4-trimethyl-1,6-diaminohexane, 1,11-diaminounodecane, 1,12-diaminododecane, 1-amino-3,3 , 5-trimethyl-5-aminomethylcyclohexane, 2,4- and / or 2,6-hexahydrotoluylenediamine, 2,4'- and / or 4,4'-diamino-dicyclohexylmethane or 3,3'-dimethyl-4,4 ' diamino-dicyclohexylmethane is obtained

m stands for an integer> 1,

and

in which

n stands for m-1,

X, radicals Rl and R2 have the abovementioned meanings, prepared by reacting polyamines of the general formula (III), wherein X and m have the abovementioned meaning, with compounds of the general formula (IV), wherein the radicals Rl and R2 have the abovementioned meaning, characterized in that the resulting polyaspartic ester composition comprises a proportion of the compound of the general formula (II) of 4% to 20% of the GC surface (measured as area% in the gas chromatogram), the proportion of the two compounds corresponds to the general formula (I) and (II), wherein the sum of the GC surfaces of the two compounds of the general formula (I) and (II) is 100% and contains a proportion of Fumarsäuredialkylester from 0.01 to 1 wt. Percent.

Methyl, ethyl, propyl, iso-propyl, butyl or iso-butyl radicals, m is 2, and

n stands for m-1,

X, radicals Rl and R2 have the abovementioned meanings, prepared by reacting polyamines of the general formula (III), wherein X and m have the abovementioned meaning, with compounds of the general formula (IV), wherein the radicals Rl and R2 have the abovementioned meaning, characterized in that the resulting polyaspartic ester composition, a proportion of the compound of general formula (II) of 4% to 15% of the GC surface area (measured as area% in the gas chromatogram), the proportion of the two Compounds of the general formula (I) and (II) corresponds, wherein the sum of the GC surfaces of the two compounds of the general formula (I) and (II) is 100% and a proportion of Fumarsäuredialkylester 0.01 to 0.1 wt. Percent contains.

Diaminodicyclohexylmethane can be obtained

R 1 and R 2 are ethyl radicals,

m stands for 2,

and

in which

n stands for m-1,

X, radicals Rl and R2 have the abovementioned meanings, prepared by reacting polyamines of the general formula (III), wherein X and m have the abovementioned meaning, with compounds of the general formula (IV), wherein the radicals Rl and R2 have the abovementioned meaning, characterized in that the resulting polyaspartic acid ester composition has a proportion of the compound of the general formula (II) of 4% to 15% of the GC surface (measured as area% in the gas chromatogram), which corresponds to the proportion of the two compounds of the general formula (I) and (II), wherein the sum of the GC surfaces of the two compounds of the general formula (I) and (II) 100% and a proportion of Fumarsäuredialkylester 0.01 to 0.1 wt. Percent contains.

The process according to the invention preferably takes place for preparing the composition comprising polyaspartic esters of the general formula (I) and one or more polyaspartic esters having primary amino groups of the general formula (II) in two steps. In the first step, the compounds of the general formula (III) and (IV) at temperatures between 0 ° C and 100 ° C, preferably 20 to 80 ° C and particularly preferably 20 to 60 ° C, in a ratio of the equivalents of the primary amino groups the compounds of general formula (III) to the C = C double bond equivalents of the compounds of general formula (IV) of 1: 1.2 to 1.2: 1, but preferably 1: 1.05 to 1.05: 1 to a residual content of compounds of the general formula (IV) from 2 to 15 wt. Percent, preferably from 3 to 10 percent by weight reacted.

In the second step, the unreacted portion of the compounds of general formula (IV) is removed by distillation.

Suitable conditions during the distillation are a pressure range between 0.01 and 2 mbar and a temperature of the bottom effluent upon exit from the distillation apparatus <170 ° C and> the temperature, which results from the following formula (V):

T (sump drain) = 27 x ln (p) + 150 (V) where T (sump drain) for the temperature of the sump drain in ° C and

p for the pressure in the distillation apparatus in mbar

stand.

By maintaining this pressure range, it is ensured that, on the one hand, moderate temperatures in the bottom effluent suffice to deplete the dialkyl fumarates to the desired extent; on the other hand, the process remains applicable on an industrial scale. At lower pressure, the gas density is too low and the necessary apparatuses so large that the process is disadvantageous from an economic point of view.

Preferably, the temperature of the bottom effluent <170 ° C, but at least 20 K above the temperature, which results from the formula (V), more preferably it is between 20 K. and 40K above the temperature resulting from formula (V) but not above 170 ° C.

Compounds of the general formula (III) which are used in the process according to the invention are all known polyamines having primary amino groups which correspond to the general formula (III). The following compounds may be mentioned by way of example: ethylenediamine, 1,2-diaminopropane, 1,4-diaminobutane, 1,5-diaminopentane, 2,5-diamino-2,5-dimethylhexane, 1,5-diamino-2-methylpentane (Dytek ®A, Fa DuPont), 1,6-diaminohexane, 2,2,4- and / or 2,4,4-trimethyl-1,6-diaminohexane, 1,1-diaminoundecane, 1,2-diaminododecane or triaminononane , Etheramines, such as 4,9-dioxadodecane-l, 12-diamine, 4,7,10-trioxatridecane-l, 13-diamine, or higher molecular weight polyether polyamines having aliphatically bonded, primary amino groups, such as those marketed under the name Jeffamine® by Huntsman , Also useful are aliphatic polycyclic polyamines, such as tricyclodecanebismethylamine (TCD-diamine) or bis (aminomethyl) norbornanes, amino-functional siloxanes, e.g. Diaminopropylsiloxane G10 DAS (from Momentive), fatty alkyl based amines, e.g. Fentamine from Solvay, dimer fatty acid diamines such as priamines from Croda.

Polyamines of the general formula (III) are preferably used in the process according to the invention wherein m = 2 and X is a cyclic hydrocarbon radical having at least one cyclic carbon ring. Examples of particularly preferably usable diamines are l-amino-3,3,5-trimethyl-5-aminomethylcyclohexane (IPDA), 2,4- and / or 2,6-hexahydrotoluylenediamine (H6-TDA), isopropyl-2,4- diaminocyclohexane, and / or isopropyl-2,6-diaminocyclohexane, 1,3-bis (aminomethyl) cyclohexane, 2,4'- and / or 4,4'-diaminodicyclohexylmethane, 3,3'-dimethyl-4,4 'diamino-dicyclohexylmethane (Laromin® C 260, BASF AG), the isomeric diaminodicyclohexylmethane having a methyl group as a core substituent (= C-monomethyl-diaminodicyclohexylmethane), 3 (4) -

Aminomethyl-l-methylcyclohexylamine (AMCA) and araliphatic diamines, such as 1,3-bis (aminomethyl) benzene or m-xylylenediamine. Also preferred in the process according to the invention are polyamines of the general formula (III) used selected from the group: polyether polyamines having aliphatically bonded primary amino groups, 1,2-diaminopropane, 1,4-diaminobutane, 1,5-diaminopentane, 1,6-diaminohexane, l , 5-diamino-2-methylpentane, 2,5-diamino-2,5-dimethylhexane, 2,2,4- and / or 2,4,4-trimethyl-1,6-diaminohexane, 1,11-diaminounodecane, 1 , 12-diaminododecane, 1-amino-3,3,5-trimethyl-5-aminomethylcyclohexane, 2,4- and / or 2,6-hexahydrotoluenediamine, 2,4'- and / or 4,4'-diamino-dicyclohexylmethane or 3,3'-dimethyl-4,4'-diamino-dicyclohexylmethane. Particularly preferred are 3,3'-dimethyl-4,4'-diamino-dicyclohexylmethane, 2,4'- and / or 4,4'-diaminodicyclohexylmethane, 1,5-diamino-2-methylpentane and very particularly preferred is the use of 2,4- and / or 4,4'-diaminodicyclohexylmethane. Particularly preferred polyaspartic acid ester compositions according to the invention are those in which X represents organic radicals obtained by removing the primary amino groups from one of the polyamines of general formula (III) selected from the group consisting of polyether polyamines having aliphatically bonded primary amino groups, 1,2 Diaminopropane, 1,4-diaminobutane, 1,5-diaminopentane, 1,6-diaminohexane, 1,5-diamino-2-methylpentane, 2,5-diamino-2,5-dimethylhexane, 2,2,4- and / or 2,4,4-trimethyl-l, 6-diaminohexane, 1,11-diaminounodecane, 1,12-diaminododecane, 1-amino-3,3,5-trimethyl-5-aminomethylcyclohexane, 2,4- and / or 2 , 6-hexahydrotoluenediamine, 2,4'- and / or 4,4'-diamino-dicyclohexylmethane or 3,3'-dimethyl-4,4'-diaminodicyclohexylmethane.

Very particular preference is given to the polyaspartic ester compositions according to the invention in which X represents organic radicals which are obtained by removal of the primary amino groups from one of the polyamines of the general formula (III) selected from the group: 3,3'-dimethyl-4, 4'diaminodicyclohexylmethane, 2,4'- and / or 4,4'-diaminodicyclohexylmethane, 1, 5-diamino-2-methylpentane.

Preferred compounds of the general formula (IV) which are used in the process according to the invention are maleic or fumaric acid esters of the general formula (IV) in which R 1 and R 2 are identical or different organic radicals each having 1 to 18 carbon atoms. R 1 and R 2 independently of one another preferably represent linear or branched alkyl radicals having 1 to 8 carbon atoms. Examples of compounds of the general formula (IV) include the following compounds: dimethyl maleate, diethyl ester, di-n or isopropyl ester, di-n-butyl ester, di-2-ethylhexyl ester or the corresponding fumaric acid esters. Particularly preferred is diethyl maleate. The polyaspartic ester compositions according to the invention are valuable reaction partners for polyisocyanates in low-solvent or -free two-component polyurethane systems.

The invention thus also relates to the use of the polyaspartic ester compositions according to the invention as a reactive component in two-component polyurethane systems or for the preparation of prepolymers. The two-component (2K) polyurethane systems containing the polyaspartic ester compositions of the invention can then be used as coating agents for the production of coatings.

In addition to the components essential to the invention, the auxiliaries which are customary in coating technology, such as inorganic or organic pigments, other organic light stabilizers, radical scavengers, paint additives, such as dispersants, leveling agents, thickeners, defoaming agents and others, can be used in the coating compositions essential to the invention Auxiliaries, adhesives, fungicides, bactericides, stabilizers or inhibitors and catalysts can be used with.

The coating compositions according to the invention are preferably used in the fields of auto-painting, automotive refinish, large-vehicle painting, plastic painting, general industrial coating, floor coating and / or wood / furniture coating

Application.

Another object of the invention are therefore also coated substrates which are obtainable using the Polyasparaginsäureester compositions according to the invention.

Experimental part

Raw materials:

Vestamin PACM: a mixture of 2,4- and 4,4'-diaminodicyclohexylmethane, manufactured by Fa. Evonik

Desmodur N 3600: a low-viscosity HDI trimer with about 23% NCO and <0.25% free HDI, manufacturer Covestro

Desmodur N 3900: a low-viscosity HDI trimer with about 23.5% NCO and <0.25% free HDI, manufacturer Covestro

Byk 331: polyether modified polydimethylsiloxane surface additive, manufacturer BYK Tinuvin 292: a mixture of bis (l, 2,2,6,6-pentamethyl-4-piperidyl) sebacate and methyl l, 2,2,6,6-pentamethyl 4-piperidyl sebacate, a light stabilizer from BASF

Tinuvin 384-2: Benzenepropanoic acid, 3- (2H-benztriazol-2-yl) -5- (1, 1-dimethylethyl) -4-hydroxy, C7- 9-branched and linear alkyl ester, a light stabilizer from BASF methods:

Fumaric acid diethylester contents were determined quantitatively by GC method with an internal standard. A 6890 gas chromatograph from Agilent was used with a standard GC capillary (100% polysiloxane phase) and a FID detector. The temperature of the injector (Sphtausgang) was 180 ° C, as a carrier gas helium was used. The limit of quantification of this method was 300 ppm.

GC-MS measurements were performed on a 6890 Gas Chromatograph and Mass Spectrum detector 5973 from Agilent with standard electronization at 70eV, a standard GC capillary (100% polysiloxane phase) and split injection at 250 ° C Injector temperature performed. The% areas of the gas chromatograms were evaluated.

All viscosity measurements were carried out with a Physica MCR 51 Rheometer from Anton Paar Germany GmbH (DE) according to DIN EN ISO 3219: 1994-10.

The NCO contents were determined titrimetrically in accordance with DIN EN ISO 11909: 2007-05.

The Hazen color numbers were measured on a LICO 400 colorimeter from Hach Lange GmbH,

Düsseldorf, determined according to DIN EN ISO 6271: 2016-05.

The amine numbers were determined titrimetrically in accordance with EN ISO 9702: 1998 (perchlorate

Method) with the exception that the results were given as amine number. The amine number in mg KOH / g was calculated according to the following equation:

(a- b) x 5.61

Amine number = -

a: the consumption, in milliliters, of perchloric acid, c = 0.1 mol 1, in the main experiment;

b: the consumption, in milliliters, of perchloric acid, c = 0.1 mol / l, in the blank test; E: the weight, in grams.

The flow times were determined in accordance with DIN EN ISO 2431: 2012-03, with the exception that a DIN 4 flow cup was used. The pot life was defined as the time to double the flow time.

The determination of the drying was carried out according to DIN EN ISO 9117-5: 2012-11.

To determine the reactivity, the following gel time measurement method was developed: The starting materials (total amount 10 g) were weighed into a beaker and mixed for 15 seconds at 3000 rpm in a speed mixer. Then a bent paperclip or a disposable pipette was used and with a stopwatch the time was determined until the mixture pulls or sets threads.

Example 1 (comparative example)

Commercially available Polyasparagi the company. Covestro under the name Desmophen

NH 1420.

Characteristics:

Monoamines of the formula (II) (GC-MS): 4.0%

Fumaric acid diethyl ester (GC) 2.9% by weight

Viscosity 1220 mPas

Color number 27 APHA

Amine number 201 mg KOH / g

Example 2 (comparative example)

341.8 g of Vestamin PACM were initially charged at 23 ° C. under dry nitrogen with stirring. 839.4 g of diethyl maleate were added dropwise so that the temperature did not rise above 60 ° C. After completion of the addition, the temperature was adjusted to 45 ° C and the

Batch was stirred at 45 ° C for one hour. Subsequently, the batch was stored at 23 ° C for 8 weeks. The content of diethyl fumarate after storage was 0.04% by weight. This gave a bright product with the following characteristics:

Monoamines of the formula (II) (GC-MS): 65.8%

Fumaric acid diethyl ester (GC) 0.04% by weight

Viscosity 690 mPas

Color number 16 APHA

Amine number 293 mg KOH / g

Example 3 (comparative example)

341.8 g of Vestamin PACM were initially charged at 23 ° C. under dry nitrogen with stirring. To this, 1678.8 g of diethyl maleate were added dropwise so that the temperature did not exceed 60 ° C has risen. After the completion of the addition, the temperature was adjusted to 45 ° C, and the reaction was stirred at 45 ° C for one hour. Subsequently, the batch was stored at 23 ° C for 24 hours. The content of diethyl fumarate after storage was 11.5% by weight. Fumaric acid diethyl ester was then distilled off at 120 ° C and 0.2 mbar. This gave a bright product with the following characteristics:

Monoamines of the formula (II) (GC-MS): 25.4%

Fumaric acid diethyl ester (GC) 0.05% by weight

Viscosity 1330 mPas

Color number 8 APHA

Amine number 224 mg KOH / g

Example 4

341.8 g P Vestamin PACM were initially charged at 23 ° C. under dry nitrogen with stirring. To this, 1678.8 g of diethyl maleate were added dropwise so that the temperature did not rise above 60 ° C. After the completion of the addition, the temperature was adjusted to 45 ° C, and the reaction was stirred at 45 ° C for 2 hours. Subsequently, the batch was stored at 23 ° C for 7 weeks. The content of diethyl fumarate after storage was 2.7% by weight. Fumaric acid diethyl ester was then distilled off at 120 ° C and 0.2 mbar. This gave a bright product with the following characteristics:

Monoamines of the formula (II) (GC-MS): 5.3%

Fumaric acid diethyl ester (GC) 0.08 weight percent

Viscosity 1810 mPas

Color number 19 APHA

Amine number 203 mg KOH / g

Example 5

341.8 g of Vestamin PACM were initially charged at 23 ° C. under dry nitrogen with stirring. To this, 1678.8 g of diethyl maleate were added dropwise so that the temperature did not rise above 60 ° C. After the completion of the addition, the temperature was adjusted to 45 ° C, and the reaction was stirred at 45 ° C for two hours. Subsequently, the batch was stored at 23 ° C for 30 hours. The content of was 8.62 wt. Percent after storage. Fumaric acid diethyl ester was then distilled off at 120 ° C and 0.2 mbar. This gave a bright product with the following characteristics:

Monoamines of the formula (II) (GC-MS): 13.2%

Fumaric acid diethyl ester (GC) <0.03 weight percent

Viscosity 1650 mPas

Color number 5 APHA Amine number 213 mg KOH / g

Example 6

341.8 g of Vestamin PACM were initially charged at 23 ° C. under dry nitrogen with stirring. To this, 1678.8 g of diethyl maleate were added dropwise so that the temperature did not rise above 60 ° C. After the completion of the addition, the temperature was adjusted to 45 ° C, and the reaction was stirred at 45 ° C for one hour. Subsequently, the batch was stored at 23 ° C for 24 hours. The content of diethyl fumarate after storage was 8.85 percent by weight. Fumaric acid diethyl ester was then distilled off at 120 ° C and 0.2 mbar. This gave a bright product with the following characteristics:

Monoamines of the formula (II) (GC-MS): 14.1%

Fumaric acid diethyl ester (GC) 0.08 weight percent

Viscosity 1630 mPas

Color number 5 APHA

Amine number 214 mg KOH / g

Prior to performance testing, the reactivity of selected polyaspartic esters was determined by the gel time measurement method described above.

Table 1. Reactivity determination by gel time measurement method

Desmodur N Desmodur N Desmodur N Desmodur N Desmodur N

feedstock

3600 3600 3600 3600 3600

Weighing 4.18 4.88 4.22 4.18 4.18

Feed Example 1 Example 2 Example 3 Example 5 Example 6

Weighing 5.82 5.11 5.78 5.82 5.82

Time to:

the sample

37 minutes * 5 minutes 49 minutes 52 minutes

Threads pulls

the sample

65 min. * 7 min 88 min 92 min

is fixed

Sample gelled in Speedmixer From Table 1 it can be seen that the composition according to the invention comprising polyaspartic esters of Examples 5 and 6 despite a higher content Polyaspartic acid ester with primary amino groups show no shortened gel time compared to the commercially available product and are therefore suitable for paints.

Testing in paints

Polyaspartic acid ester compositions according to the invention from Examples 1 and 5 were tested in coating formulations.

Preparation of a master varnish

To the amount of component A given in Table 2, the additives and the amount of butyl acetate given in the table were added and stirred thoroughly.

Preparation of the hardener solution

To the amount of component B given in Table 2, the given amount of butyl acetate was added and stirred intimately.

Mixing of the base lacquer with the hardener and application:

The stock listed above and the hardener were each mixed together and stirred intimately. The mixtures were then each applied with an air gun to Coil Coat sheets precoated with black basecoat, flashed for 10 minutes at room temperature and then dried at room temperature and at 60 ° C. There were brilliant, high-gloss coatings with a layer thickness of 50 μηι obtained.

An overview of the determined coating properties of the coatings is shown in Table 3.

Table 2. Composition of masterbatches

Temperature: 24 ° C Example 7 Example 8 Example 9

According to the invention comparison

Humidity: 48%

Component A

Example 5 43.77

Example 4 45.25

Example 1 47.24

Byk 331 (10% in BA) 0.08 0.08 0.08

Tinuvin 292 (50% in BA) 0.16 0.17 0.16

Tinuvin 384 - 2 (50% in 0.33 0.33 0.33

BA) Butyl acetate 21.34 20.00 16.19

Component B

Desmodur N 3900 (100%) 29.75 29.42 30.65

Butyl acetate 1.57 1.75 2.35

Table 3. Coating properties of coating

Comparison of the coating properties given in Table 3 from the comparison coating (Example 9) with those of the coatings according to the invention (Examples 7 and 8) shows a faster drying with the same pot life of the coatings according to the invention.

Claims

claims

1. Composition comprising one or more polyaspartic esters of the general formula (I)

in which

Carbon atoms, m is an integer> 1,

and

(Π)

in which

n stands for m-1,

X, radicals R 1 and R 2 have the abovementioned meanings, characterized in that the proportion of the compound of the general formula (II) is from 4% to 15% of the GC surface (measured as area% in the gas chromatogram) corresponds, wherein the sum of the GC surfaces of the two compounds of the general formula (I) and (II) is 100% and a proportion of Fumarsäuredialkylester of 0.01 to 1 wt. Percent is present.

Process for the preparation of the composition comprising one or more polyaspartic esters of the general formula (I)

m

(I)

in which

and

in which n stands for m-1,

(HD,

R100C- C H = C H-COOR2

(IV),

wherein the radicals Rl and R2 have the abovementioned meaning, and a distillative removal of the unreacted portion of the compound of the general formula (IV), characterized in that the resulting polyaspartic ester composition comprises a proportion of the compound of the general formula (II) 4% to 15% of the GC surface (measured as area% in the gas chromatogram), wherein the sum of the GC surfaces of the two compounds of the general formula (I) and (II) is 100% and a proportion of Fumarsäuredialkylester from 0.01 to 1 percent by weight contains.

Use of the polyaspartic ester compositions according to claims 1 to 2 as a reactive component in two-component polyurethane systems or for the preparation of prepolymers.

Coated substrates obtainable using the polyaspartic ester compositions of claims 1 to 2.