EP1620513A2

EP1620513A2 - Autocatalyzed, thermosetting materials that are free from external catalysts and are based on condensates of epoxy-functional silanes, and use thereof for the production of thermosetting materials

Info

Publication number: EP1620513A2
Application number: EP04729104A
Authority: EP
Inventors: Elke Westhoff; Manuela Niemeier; Wilfried STÜBBE; Andreas Poppe
Original assignee: BASF Coatings GmbH
Current assignee: BASF Coatings GmbH
Priority date: 2003-05-08
Filing date: 2004-04-23
Publication date: 2006-02-01
Also published as: WO2004099322A3; US20070166550A1; US7501480B2; DE10320432A1; JP2006525388A; WO2004099322A2; JP4714141B2

Abstract

Disclosed are autocatalyzed, thermosetting materials that are free from external catalysts and contain condensates of silanes comprising hydrolyzable atoms and/or hydrolyzable groups and (i) non-hydrolyzable groups which comprise epoxide groups and are free from isocyanate adduct groups as well as non-hydrolyzable, epoxide group-free groups with (a) bivalent, bonding -NH-C(X)-X- and/or -X-(X)C-NH- urethane groups, (b) bivalent, bonding -HN-C(X)-NH- urea groups, and/or (c) monovalent, terminal Y-C(X)-NH- groups, wherein the variable X represents an oxygen atom or sulfur atom while the variable Y represents the radical of a blocking agent for isocyanate groups; or (ii) non-hydrolyzable groups with epoxide groups and groups (a), (b), and/or (c); or (iii) non-hydrolyzable groups with epoxide groups, which are free from isocyanate adduct groups, non-hydrolyzable, epoxide group-free groups with groups (a), (b), and/or (c), and non-hydrolyzable groups with epoxide groups and groups (a), (b), and/or (c). Also disclosed are a method for the production of the inventive autocatalyzed, thermosetting materials and the use thereof for producing thermosetting materials.

Description

Autocatalyzed, thermally curable compositions based on condensates epoxyfunctional Siiane free of external catalysts and their use for the production of thermally hardened compositions

Field of the Invention

The present invention relates to new, autocatalyzed, thermosetting compositions free from external catalysts based on condensates epoxyfunctional Siiane. In addition, the present invention relates to the use of the new, autocatalyzed, thermally curable compositions free from external catalysts, based on condensates epoxyfunctional Siiane, for the production of thermally hardened compositions, in particular coatings and paints, as well as moldings, in particular optical moldings, and self-supporting foils.

State of the art

Thermally curable compositions based on condensates epoxyfunctional Siiane, which do not contain urethane groups, are from the patent applications EP 1 179 575 A 2, WO 00/35599 A, WO 99/52964 A, WO 99/54412 A, DE 197 26 829 A 1 or DE 19540 623 A1. They are used in particular for the production of highly scratch-resistant coatings. It is essential that external catalysts or starters for the conversion of the epoxy groups (cf., for example, WO 99/52964 A, page 8, line 29, to page 9, line 20) must be added to these known thermally curable compositions so that the Cure masses at comparatively low temperatures of 100 to 160 ° C at a practical speed. However, the use of external catalysts has numerous disadvantages.

In this way, the processing time or pot life of the known thermally curable compositions is greatly reduced.

If they are to be used for the production of coatings with a layer thickness of more than 20 μm, such as is used, for example, in the clearcoats of original automotive coatings, they must be modified so that the resulting coatings do not

Show stress cracks. This is known to be done by the

Installation of flexibilizing, the tension-absorbing

Structural elements in the three-dimensional inorganic-organic hybrid networks. To achieve this, binders are added to the known, thermally curable compositions, which are usually present in aqueous-alcoholic media, which are stable in these media. These binders are preferably in the form of aqueous dispersions. However, these often show a strong interaction with the catalysts used, so that they cannot be used together. This eliminates numerous conceivable possibilities for advantageously modifying the known thermally curable compositions.

From the German patent application DE 199 108 876 A 1 thermally curable compositions based on condensates of silanes of the general formula i

X _m SiRι. _m Y _n (i)

known. In the general formula i, the variables X stand for hydrogen, halogen, alkoxy, acyloxy, alkylcarbonyl, alkoxycarbonyl, or -NR ' ₂ (R' = hydrogen and / or alkyl).

The variables R can be the same or different and represent alkyl, alkenyl, alkynyl, aryl, arylalkyl, alkylaryl, arylalkenyl, alkenylaryl, arylalkynyl or alkynylaryl, these radicals being represented by oxygen or sulfur atoms or the groups -NR'- or -N ( H) C (O) O- (urethane) can be interrupted and one or more substituents from the group of the halogens and the optionally substituted amino, amide, aldehyde, keto, alkylcarbonyl, carboxy, mercapto, Can carry cyano, hydroxy, alkoxy, alkoxycarbonyl, sulfonic acid, phosphoric acid, methacryloxy, epoxy or vinyl groups.

The variable Y stands for blocked isocyanate groups.

The indices m and n stand for integers from 1 to 3.

These obligatory Siiane can with the optional silanes of the general formula ii

X SiR ^ Zn (ii)

be co-condensed. In this general formula ii, the index n stands for an integer from 1 to 4. The variables X and R have the meaning given above. The variable Z stands for hydroxyl, amino, NH (CH ₂ ) 2NH ₂ or epoxy groups.

Accordingly, a myriad of compounds fall under the general formula i, which can also be combined with an equally large number of compounds of the general formula ii. Although the reaction product of 3-isocyanatopropyltriethoxysilane and glycidol is mentioned as an example of a silane ii in FIG. 6 of German patent application DE 199 10 876 A1, no information is given about the thermally curable compositions concerned or the compound in any form turned out to be particularly advantageous or at least used as an example.

In addition, it is essential for the known thermally curable compositions that they are crosslinked primarily via the blocked isocyanate groups. However, particularly high temperatures and long curing times must be used (cf. DE 199 10 876 A 1: Example 1, page 3, line 43: 180 ° C / 45 minutes; Example 2, page 4, line 32: 180 ° C / 30 minutes). However, these are conditions that are completely unsuitable for processes in economically important areas such as automotive OEM painting.

Object of the invention

The object of the present invention was to provide new thermally curable compositions based on condensates epoxyfunctional Siiane, which no longer have the disadvantages of the prior art, but which can also be cured rapidly at relatively low temperatures even without external catalysts or starters. In addition, these new thermally curable compositions should be able to be easily modified in such a way that they deliver thermally hardened compositions, in particular coatings and paints, as well as moldings, in particular optical moldings, and self-supporting foils, which are chemical-resistant, highly scratch-resistant, high-gloss, flexible, transparent and clear , the thermally hardened masses, in particular the coatings and the paints, in Dry layer thicknesses> 30 μm no longer show stress cracks and no delamination from the substrates and can therefore be used more widely than the previously known thermally curable compositions based on condensates epoxyfunctional Siiane. In particular, the new thermally hardened masses produced from the new thermally curable masses should have a high scratch resistance in conjunction with a high chemical resistance and should be suitable for the production of clearcoats for the automotive coating.

In addition, it was the object of the present invention to provide a new process for the preparation of thermally cured compositions from thermally curable compositions based on condensates epoxyfunctional Siiane, which can be carried out more easily than the processes for the preparation of the known thermally cured compositions and in particular without them Use of external catalysts and starters.

The solution according to the invention

Accordingly, the new, autocatalyzed, thermally curable compositions free from external catalysts have been found which contain at least one condensate of at least one epoxy-functional silane, selected from the group of Siiane, which have at least one hydrolyzable atom and / or a hydrolyzable group and

(i) at least one non-hydrolyzable, isocyanate adduct group-free group with at least one

Epoxy group and at least one non-hydrolyzable, epoxy group-free group with at least one group selected from the group consisting of (a) double-bonded, copper-bonding urethane groups -NH-C (X) -X- and -X- (X) C-NH-,

(b) double-bonded, copper-forming urea groups -HN-C (X) -NH- and (c) single-bonded, terminal groups Y-C (X) -NH-,

wherein the variable X represents an oxygen or sulfur atom and the variable Y represents the remainder of a blocking agent for isocyanate groups; or

(ii) at least one non-hydrolyzable group with at least one epoxy group and at least one group selected from the group consisting of groups (a), (b) and (c), or

(iii) at least one non-hydrolyzable, isocyanate adduct group-free group with at least one epoxy group, at least one non-hydrolyzable, epoxy group-free group with at least one group selected from the group consisting of groups (a), (b) and (c), and at least one, preferably one, non-hydrolyzable group with at least one epoxy group and at least one group selected from the group consisting of groups (a), (b) and (c),

contain.

In the following, the new, auto-catalyzed, thermally curable compositions free from external catalysts based on condensates epoxyfunctional Siiane are referred to as "compositions according to the invention". In addition, the new process for the production of thermally hardened masses from thermally hardenable masses based on condensates epoxyfunctional Siiane was found, in which at least one mass according to the invention is thermally hardened in the absence of external catalysts and which is referred to below as the “method according to the invention”.

The advantages of the invention

In view of the prior art, it was surprising and unforeseeable for the person skilled in the art that the object on which the present invention was based could be achieved with the aid of the compositions according to the invention and the method according to the invention.

In particular, it was surprising that the compositions according to the invention could be cured rapidly at comparatively low temperatures even without external catalysts or starters. The compositions according to the invention had a considerably longer pot life or processing time than the known thermally curable compositions, which considerably simplified their use in operational practice.

In addition, the compositions according to the invention could be modified without problems in such a way that they provided thermally cured compositions, in particular coatings and coatings, and also moldings, in particular optical moldings, and self-supporting films, which were chemical-resistant, highly scratch-resistant, high-gloss, flexible, transparent and clear, the thermally hardened compositions, in particular the coatings and the coatings, in dry layer thicknesses> 30 μm no longer showed any stress cracks and no delamination from the substrates and were therefore more widely applicable than the previously known thermally curable compositions based on condensates epoxy function studio Siiane. In particular, the compositions according to the invention are outstandingly suitable for the production of clearcoats for the automotive OEM coating.

It was also surprising that the process according to the invention was easier to carry out than the processes for producing the known thermally hardened compositions and, in particular, did not require the use of external catalysts and starters.

Detailed description of the invention

In the context of the present invention, “autocatalyzed” means that the thermal curing of the compositions according to the invention is catalyzed by starting products and / or intermediates which are formed in the thermal curing (cf. Römpp Online, Georg Thieme Verlag, Stuttgart, 2002, “Autocatalysis ").

In the context of the present invention, external catalysts or starters are understood to mean substances which usually catalyze the thermal curing of thermally curable compositions via epoxy groups. According to experts, such catalysts are fundamentally necessary to achieve practical results (cf. Johan Bieleman, "Lackadditive", Wiley-VCH, Weinheim, New York, 1998, "7.2.4 Epoxy Resin Systems", pages 263 to 269). Further examples of catalysts of this type, which are also used in thermally curable compositions based on condensates epoxyfunctional Siiane, are for example from the international patent application WO 99/52964 A, page 8, line 29, to page 9, line 20, or German patent application DE 197 26 829 A 1, column 3, line 65, to column 4, line 64, known. In the context of the present invention, “free from external catalysts” means that the compositions according to the invention do not contain any external catalysts or only those amounts thereof which do not shape the property profile of the compositions according to the invention, but at most have an insignificant effect.

In the context of the present invention means

"Isocyanate adduct group-free group" means that the group in question is free from adduct groups which result from reactions of isocyanate groups with isocyanate-reactive functional groups or compounds, such as urethane groups, urea groups or blocked isocyanate groups.

The compositions according to the invention contain at least one condensate of at least one epoxy-functional silane. As is known, condensates are formed by the hydrolysis and condensation of silanes containing hydrolyzable groups according to the so-called sol-gel process (cf. Römpp Online, Georg Thieme Verlag, Stuttgart, 2002, “Sol-gel process”).

According to the invention, the silane contains at least one hydrolyzable atom and / or at least one hydrolyzable group. It preferably contains at least two, in particular at least three, hydrolyzable atoms and / or at least two, in particular at least three, hydrolyzable groups.

In a first embodiment (i) according to the invention, the silane also contains mandatory at least one, in particular one, non-hydrolyzable, isocyanate adduct group-free group with at least one epoxy group and

- At least one, in particular one, non-hydrolyzable, epoxy group-free group with at least one, in particular one, group selected from the group consisting of

(a) double-bonded, copper-bonding urethane groups -NH-C (X) -X- and -X- (X) C-NH-,

(b) double-bonded, copper-forming urea groups -HN-C (X) -NH- and

(c) monovalent terminal groups Y-C (X) -NH-,

wherein the variable X stands for an oxygen or sulfur atom, in particular an oxygen atom, and the variable Y stands for the rest of a blocking agent for isocyanate groups.

In a second embodiment (ii) according to the invention, the silane also contains mandatory

at least one, in particular one, non-hydrolyzable group with at least one, in particular one, epoxy group and at least one, in particular one, group selected from the group consisting of groups (a), (b) and (c).

In a third embodiment (iii) according to the invention, the silane also contains mandatory at least one, in particular one, non-hydrolyzable, isocyanate adduct group-free group with at least one epoxy group,

- At least one, in particular one, non-hydrolyzable, epoxy group-free group with at least one, in particular one, group selected from the group consisting of groups (a), (b) and (c), and

- At least one, in particular one, non-hydrolyzable group with at least one epoxy group and at least one, in particular one, group selected from the group consisting of groups (a), (b) and (c).

In the case of the urethane group -NH-C (X) -X- the NH function within the group in question is oriented toward the silicon atom, in the case of the urethane group -X- (X) C-NH- this function is within the group in question Silicon atom facing away. The orientation results from the structure of the starting products and the manufacturing process used for the epoxy-functional Siiane of the embodiments (i) to (iii) according to the invention.

As hydrolyzable atoms, hydrolyzable groups, non-hydrolyzable, isocyanate adduct group-free groups with at least one epoxy group, non-hydrolyzable, epoxy group-free group with at least one group (a), (b) and / or (c) and non-hydrolyzable groups with at least one epoxy group and at least one Group (a), (b) and / or (c) are all atoms and groups which are customary and known in the field of silane chemistry and are described, for example, in patent applications EP 1 179 575 A 2, WO 00/35599 A, WO 99/52964, WO 99/54412 A, DE 197 26 829 _A. 1, DE 195 40 623 A 1 and DE 199 10 876 A 1 are described, as well as all blocked isocyanate groups (c), which are known to result from the reactions of isocyanate groups with blocking agents, as described, for example, in German patent application DE 199 14 896 A 1, column 12, Row 11 until column 13, row 2, is known.

The siiane of embodiment (ii) according to the invention are preferably used.

The silane from the group consisting of silanes of the general formulas la is preferred:

Z _m SiR _n R ¹ ₀ (la),.

where the indices and the variables of the formula la have the following meaning:

Z hydrolyzable, non-isocyanate-reactive atom and / or hydrolyzable, monovalent, non-isocyanate-reactive group;

R non-hydrolyzable, single-bonded organic group containing at least one epoxy group;

R ¹ non-hydrolyzable, single-bonded organic group, containing no epoxy group;

m 1, 2 or 3;

n 1, 2 or 3; and o 0, 1 or 2;

with the proviso that m + n + o = 4; and

from silanes of the general formulas Ib:

(Z _m R ¹ _o Si) _p R ² (Ib),

wherein the variables Z and R ¹ and the indices m and o have the meaning given above, the index p = at least 2 and the variable R ² denotes a non-hydrolyzable, multi-bonded organic group containing at least one epoxy group;

with the proviso that at least one group R and / or R ^{1 of} the general formula la and at least one group R1 and / or R2 of the general formula Ib at least one group selected from the group consisting of

(a) divalent verkupfenden urethane groups -NH-C (X) -X- and -X (X) ^C-NH-:

(b) double-bonded, copper-forming urea groups -HN-C (X) -NH- and

(c) monovalent terminal groups Y-C (X) -NH-,

wherein the variable X stands for an oxygen or sulfur atom, in particular an oxygen atom, and the variable Y stands for the rest of a blocking agent for isocyanate groups; contains;

selected. Examples of suitable blocking agents are the blocking agents known from US Pat. No. 4,444,954 A1:

(1) phenols such as phenol, cresol, xylenol, nitrophenol, chlorophenol, ethylphenol, t-butylphenol, hydroxybenzoic acid, esters of this acid or 2,5-di-tert-butyl-4-hydroxytoluene;

(2) lactams such as ε-caprolactam, δ-valerolactam, γ-butyrolactam or ß-propiolactam;

(3) active methylenic compounds such as diethyl malonate, dimethyl malonate, ethyl or methyl acetoacetate or acetylacetone;

(4) alcohols such as methanol, ethanol, n-propanol, isopropanol, n-

butanol; Isobutanol, t-butanol, n-amyl alcohol, t-amyl alcohol,

Lauryl alcohol, ethylene glycol monomethyl ether,

Ethylene glycol monoethyl ether, ethylene glycol monopropyl ether

R ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, propylene glycol monomethyl ether,

Methoxymethanol,. Glycolic acid, glycolic acid ester, lactic acid, lactic acid ester, methylolurea, methylolmelamine,

Diacetone alcohol, ethylene chlorohydrin, ethylene bromohydrin, 1,3-dichloro-2-propanol, 1,4-cyclohexyldimethanol or acetocyanhydrin;

(5) mercaptans such as butyl mercaptan, hexyl mercaptan, t-butyl mercaptan, t-dodecyl mercaptan, 2-mercaptobenzothiazole, thiophenol, methylthiophenol or ethylthiophenol; (6) acid amides such as acetoanilide, acetoanisidinamide, acrylamide, methacrylamide, acetic acid amide, stearic acid amide or benzamide;

(7) imides such as succinimide, phthalimide or maleimide;

(8) amines such as diphenylamine, phenylnaphthylamine, xylidine, N-phenylxylidine, carbazole, aniline, naphthylamine, butylamine, dibutylamine or butylphenylamine;

(9) imidazoles such as imidazole or 2-ethylimidazole;

(10) ureas, such as urea, thiourea, ethylene urea, ethylene thiourea or 1,3-diphenylurea;

(11) carbamates such as phenyl N-phenylcarbamate or 2-oxazolidone;

(12) imines such as ethyleneimine;

(13) oximes, such as acetone oxime, formal doxime, acetaldoxime, acetoxime, methyl ethyl ketoxime, diisobutyl ketoxime, diacetyl monoxime,

Benzophenone oxime or chlorohexanone oximes;

(14) Sulfuric acid salts such as sodium bisulfite or potassium bisulfite;

(15) hydroxamic acid esters such as benzyl methacrylohydroxamate or allyl methacrylohydroxamate; or

(16) substituted pyrazoles or triazoles; such as (17) Mixtures of these blocking agents, in particular dimethylpyrazole and triazoles, malonic esters and acetoacetic acid esters or dimethylpyrazole and succinimide.

In the general formulas Ia and Ib, the variable Z stands for a hydrolyzable, non-isocyanate-reactive atom and / or a hydrolyzable, monovalent, non-isocyanate-reactive group. The hydrolyzable atom Z is preferably selected from the group consisting of fluorine atoms, chlorine atoms and bromine atoms. The hydrolyzable, monovalent group Z is preferably selected from the group consisting of monovalent organic groups. The monovalent organic groups Z preferably consist of at least one, in particular one, monovalent organic radical which is selected from the group consisting of branched and unbranched, cyclic and non-cyclic alkyl, alkenyl and alkynyl and aryl groups and one Oxygen atom or sulfur atom or a carbonyl group or carboxyl group, in particular an oxygen atom, which links the monovalent organic radical to the silicon atom. Alkoxy groups having 1 to 4 carbon atoms in the alkyl radical, in particular methoxy, ethoxy, propoxy and butoxy groups, are particularly preferably used as hydrolyzable, monovalent, organic groups Z.

As far as the nomenclature of the organic groups Z (for example arylalkynyl) composed of at least two different radicals is concerned, the former radical (= aryl) denotes the radical which links to the silicon atom via the oxygen atoms, sulfur atoms, carbonyl groups or carboxyl groups, in particular the oxygen atoms is. In the general formula Ia, the variable R stands for a non-hydrolyzable, single-bonded organic group containing at least one, in particular a final, epoxy group. The non-hydrolyzable, monovalent organic group R, containing at least one epoxy group, is preferably selected from the group consisting of branched and unbranched alkyl, alkenyl, alkynyl, aryl, arylalkyl, alkylaryl, arylalkenyl, alkenylaryl, arylalkynyl or alkynylaryl groups, where the alkyl, alkenyl and alkynyl groups can also be cyclic. Alkyl groups and alkylcycloalkyl groups are particularly preferably used.

As far as the nomenclature of the organic groups R (for example arylalkynyl) composed of at least two different radicals is concerned, the former radical (= aryl) denotes the radical which is directly linked to the silicon atom.

In the general formula Ib, the variable R ^{2 stands} for a non-hydrolyzable, multi-bonded, in particular double-bonded, organic group containing at least one, in particular a final, epoxy group. The non-hydrolyzable, monovalent organic group R, containing at least one epoxy group, is preferably selected from the group consisting of branched and unbranched alkyl, alkenyl, alkynyl, aryl, arylalkyl, alkylaryl, arylalkenyl, alkenylaryl, arylalkynyl or alkynylaryl groups, where the alkyl, alkenyl and alkynyl groups can also be cyclic. Alkyl groups and alkylcycloalkyl groups are particularly preferably used. Regarding the nomenclature, reference is made to the explanations regarding group R.

In the general formulas Ia and Ib, the variable R ¹ denotes a non-hydrolyzable, single-bonded organic group which contains no epoxy groups. The groups R ¹ are preferably selected from the group consisting of branched and unbranched alkyl, alkenyl, alkynyl, aryl, arylalkyl, alkylaryl, arylalkenyl, alkenylaryl, arylalkynyl or alkynylaryl groups, the alkyl, alkenyl - And alkynyl groups can also be selected cyclically. Regarding the nomenclature, reference is made to the explanations regarding group R.

In the general formula, the index m stands for 1, 2 or 3, in particular 3, the index n for 1, 2 or 3, in particular 1, and the index o for 0, 1 or 2, in particular 0, with the proviso that m + n + o = 4.

At least one group R and / or R ¹ , in particular at least one group R, of the general formula Ia and at least one group R ¹ and / or R ² , in particular at least one group R ² , of the general formula Ib contains or contain at least one, in particular one of the groups (a), (b) and / or (c) described above.

The non-hydrolyzable organic groups R, R ¹ and R ² can still be substituted. It is important here that the substituents are inert in the sense that they do not interfere with the production of Siiane la and Ib, the sol-gel process or the crosslinking via the epoxy groups, in particular that they do not inhibit these reactions or start them prematurely or lead to unwanted by-products. Examples of suitable substituents are halogen atoms, in particular fluorine atoms, nitrile groups, alkoxy groups or alkoxycarbonyl groups. The groups R, R ¹ and R ² are preferably unsubstituted.

The non-hydrolyzable organic groups R, R ¹ and R ² can also contain divalent functional groups different from the groups (a), (b) and / or (c) described above. Here too is it is essential that these functional groups are inert in the sense that they are neither the sol-gel process nor cross-linking via the

Epoxy groups interfere, especially that they do not inhibit these reactions or start them prematurely or lead to undesirable by-products. Examples of suitable functional groups are

Ether, thioether, carboxylic acid ester, thiocarboxylic acid ester, carbonate,

Thiocarbonate, phosphoric acid ester, thiophosphoric acid ester,

Phosphonic acid ester, thiophosphonic acid ester, phosphite, thiophosphite

^" , Sulfonic acid ester, amide, amine, thioamide, phosphoric acid amide, thiophosphoric acid amide, phosphonic acid amide,

Thiophosphonic acid amide, sulfonic acid amide, imide, hydrazide, carbonyl,

Thiocarbonyl, sulfone or sulfoxide groups.

The Siiane of the general formula la or Ib can be prepared by a wide variety of organic and chemical processes. It is essential that manufacturing processes are used, by means of the groups (a), (b) and / or (c) described above into groups R and / or R ^{1 of} the formula or into groups R ¹ and / or R ² of Formula Ib will be introduced. This is preferably produced by reacting suitable starting products (A) which contain at least one, in particular one, free isocyanate group and suitable starting products (B) which contain at least one, in particular one, isocyanate-reactive functional group, in particular a hydroxyl group , The starting products (B) particularly preferably also comprise at least one epoxy group. The epoxy groups are mandatory in the starting products (B) if they are not already in the starting products (A).

The Siiane of the general formulas la and Ib are particularly preferred by the reaction of (A) silanes of the general formula II containing isocyanate groups:

(Z _m R ¹ ₀ Si) _p R ³ (II),

where the index m = 1, 2 or 3, in particular 3; the index o = 0, 1 or 2, in particular 0; the index p = 1, 2 or an integer> 2, in particular 1 or 2; the variable Z has the meaning given above and the variable R ³ for a non-hydrolyzable organic group containing at least one, preferably one, in particular one, free, isocyanate group, selected from the group consisting of branched and unbranched alkyl, alkenyl -, Alkynyl, aryl, arylalkyl, alkylaryl, arylalkenyl, alkenylaryl, arylalkynyl or alkynylaryl groups, where the alkyl, alkenyl and alkynyl groups can also be cyclic, but especially alkyl groups; and

(B) Compounds of the general formula I

(HO) _q R ⁴ (III),

wherein the index q = 1 or 2, in particular 1, and the variable R ⁴ for one, preferably at least one, preferably one, in particular a final epoxy group-containing organic group selected from the group consisting of branched and unbranched alkyl, Alkenyl, alkynyl, aryl, arylalkyl, alkylaryl, arylalkenyl, alkenylaryl, arylalkynyl or alkynylaryl groups, where the alkyl, alkenyl and alkynyl groups can also be cyclic, but especially alkyl groups. The groups R ³ and R ⁴ can contain the substituents and / or functional groups described above for the non-hydrolyzable organic groups R, R ¹ and R ² . With regard to the nomenclature of groups R ³ and R ⁴ , reference is made to the explanations relating to group R.

Examples of highly suitable starting products (A) are 3-isocyanatopropyltriethoxysilane and the reaction product of isophorone diisocyanate with bis (3-triethoxysilylpropyl) amine (Dynasilan® 1122 from Degussa) in a molar ratio of 1: 1.

An example of a suitable starting material (B) is glycidol.

Accordingly, the reaction product of glycidol with 3-isocyanatopropyltriethoxysilane and the reaction product of glycidol with the reaction product of isophorone diisocyanate with bis (3-triethoxysilylpropyl) amine (Dynasilan ® 1122 from Degussa) are particularly preferably used as Siiane in a molar ratio of 1: 1.

To produce a composition according to the invention, at least one, in particular one, of the Siiane la or Ib described above is hydrolyzed and condensed in a customary and known manner. The condensation is preferably carried out in an aqueous phase. The silane la or Ib can be metered into the aqueous phase or the aqueous phase can be metered into a liquid organic phase which contains the silane la or Ib or consists thereof. The silane la or Ib is preferably metered into the aqueous phase. The condensation is preferably carried out in the presence of an organic or inorganic, in particular an organic, acid. Acetic acid is preferably used. The reaction temperatures at which the condensation is carried out can vary widely; it is preferably carried out at a temperature of from -10 to + 50, preferably 0 to + 40 and in particular + 10 to + 30 ° C. It is advisable to allow the resulting reaction mixture to react for an hour to three days, in particular between 8 and 16 hours.

The content of the mass according to the invention in the silane la or Ib or its condensate can vary very widely and depends on its intended use and the viscosity which is advantageous for the application. The content is preferably 10 to 80, preferably 15 to 75, particularly preferably 20 to 70 and in particular 25 to 65% by weight, in each case based on the composition according to the invention.

The compositions according to the invention can contain at least one modifier. Examples of suitable modifying agents are additives such as are usually used in the field of coating materials, such as binders, crosslinking agents, pigments, radiation-curable substances, reactive diluents and additives (cf., for example, German patent application DE 199 30 665 A1, page 4, line 17 , to page 13, line 20). When selecting the modifying agents, care must be taken to ensure that they have no catalytic effect with regard to the crosslinking of the compositions according to the invention via the epoxy groups or that they contain no such constituents.

Examples of suitable modifiers are binders, especially in the form of their aqueous dispersions. Particularly suitable binders and aqueous dispersions and the processes for their preparation are known, for example, from German patent application DE 199 30 665 A1, page 3, lines 15 to 47, and page 4, line 17 to page 9, line 2. The content of the binders in the compositions according to the invention can vary very widely and depends on their intended use and on the hardness and scratch resistance required for this. The content is preferably 0.1 to 20, preferably 0.2 to 15, particularly preferably 0.3 to 12.5 and in particular 0.5 to 10% by weight, in each case based on the composition according to the invention.

The modifiers can be added before, during or after the condensation of the silane. They are preferably added to the relevant mass according to the invention after the condensation of the silane. Conventional and known mixing methods and devices, such as stirred kettles, dissolvers, Ultraturrax, in-line dissolvers, agitator mills or extruders, can be used.

The compositions of the invention are used to produce thermally cured compositions, in particular coatings, paints, moldings, in particular optical moldings, and self-supporting films. The coatings, paints and self-supporting foils serve in particular to protect surfaces of all types of substrates from damage by mechanical action, in particular to protect them from scratches, and / or to decorate them. The substrates are primarily all means of transportation, in particular muscle-powered means of transportation, such as bicycles or trolleys, aircraft, such as airplanes or zeppelins, floating bodies, such as ships or buoys, rail vehicles, and motor vehicles, such as motorcycles, buses, trucks or Cars, or parts thereof, structures, furniture, windows and doors, small industrial parts, coils, containers, packaging, white goods, foils, optical components, electrical components, mechanical components and hollow glass bodies. Further examples of uses and substrates are from the German patent application DE 198 16 136 A1, column 7, line 54, to column 8, line 58.

The compositions according to the invention are particularly preferably used for the production of highly scratch-resistant clearcoats in the context of automotive OEM (OEM) painting with multi-layer paint and / or effect paint. As is known, these particularly high-quality multi-layer coatings are produced by what are known as wet-on-wet processes, as are known, for example, from German patent application DE 199 30 665 A1, page 15, lines 15 to page 16, line 24.

For the production of the coatings and varnishes according to the invention, the compositions according to the invention are applied with the aid of the suitable processes known and customary for the respective intended use, such as Spraying, knife coating, brushing, pouring, dipping, watering, trickling or rolling. The substrate to be coated can rest as such, with the application device or system being moved. However, the substrate to be coated, in particular a coil, can also be moved, the application system being at rest relative to the substrate or being moved in a suitable manner.

For the production of the molded parts according to the invention, the compositions according to the invention are poured into suitable hollow molds and cured therein, after which they are separated from the hollow molds.

The usual and known methods such as casting or film blowing are used for the production of the films according to the invention. The compositions of the invention can be cured after a certain period of rest. It can have a duration of 30 seconds to 2 hours, preferably 1 minute to 1 hour and in particular 1 to 45 minutes. The rest period is used, for example, for the course and degassing of the paint layers or for the evaporation of volatile components. The rest period can be supported and / or shortened by the use of elevated temperatures up to 90 ° C and / or by a reduced air humidity <10 g water / kg air, in particular <5 g / kg air, provided that there is no damage or changes to the invention Crowds enter, such as early, complete networking.

The thermal hardening has no special features in terms of method, but is carried out according to the usual and known methods such as heating in a forced air oven or irradiation with IR lamps. The thermal hardening can also be carried out in stages. Another preferred curing method is near infrared curing (NIR radiation). A method is particularly preferably used in which the constituent water is rapidly removed from the wet layers. Suitable processes of this type are described, for example, by Roger Talbert in Industrial Paint & Powder, 04/01, pages 30 to 33, "Curing in Seconds with NIR", or in Galvanotechnik, Volume 90 (11), pages 3098 to 3100, "Lackiertechnik, NIR drying every second of liquid and powder coatings «.

The thermal curing is advantageously carried out at a temperature of 50 to 170, particularly preferably 60 to 165 and in particular 80 to 150 ° C. for a time of 1 minute to 2 hours, particularly preferably 2 minutes to 1 hour and in particular 3 to 30 minutes , Surprisingly, the thermal curing of the compositions according to the invention takes place quickly and easily without the use of external catalysts. The absence of external catalysts has the additional advantage that the resulting thermally cured compositions according to the invention do not contain any catalyst residues which lead to discoloration, odor problems and / or damage to substrates and / or individual or more layers of colored and / or multi-layer coatings could.

Examples and comparative tests

Production Example 1

The preparation of an epoxy-functional, urethane-containing silane of the general formula la

In a flask equipped with a reflux condenser and a stirrer, 24.737 g (0.1 mol) of 3-isocyanatopropyltriethoxysilane and 7.41 g (0.1 mol) of glycidol were combined under nitrogen and heated to 60 ° C. with stirring. The reaction was complete after 16 hours, which was demonstrated by the disappearance of the isocyanate band in the IR spectrum of the reaction mixture.

Preparation example 2

The preparation of an epoxy-functional, urethane-containing silane of the general formula Ib

In a flask equipped with a reflux condenser and a stirrer, 15.34 g of isophorone diisocyanate (0.069 mol) were placed under nitrogen. dissolved in 11.56 g of methyl ethyl ketone and cooled to 10 ° C. Then 29.38 g (0.069 mol) of bis (3-triethoxysilylpropyl) amine (Dynasilan © 1122 from Degussa) were slowly metered in with stirring. After the addition was complete, the reaction mixture was slowly warmed to room temperature. Then 5.27 (0.07 mol) glycidol was slowly added to the resulting mixture. The resulting reaction mixture was stirred under nitrogen at room temperature for 14 hours and at 60 ° C. for 10 hours, after which the reaction had ended (detection by the disappearance of the isocyanate band in the IR spectrum of the reaction mixture).

Preparation example 3

The preparation of a binder dispersion

609.2 parts by weight of deionized water were placed in a reaction vessel equipped with a stirrer, reflux condenser and two feed vessels and heated to 90.degree. Then two separate feeds were initially metered in parallel at 90 ° C. Feed 1 consisted of 46 parts by weight of potassium peroxodisulfate dissolved in 900 parts by weight of deionized water. Feed 2 consisted of 163.6 parts by weight of tertiary-butyl methacrylate, 16.1 parts by weight of methyl methacrylate, 270.7 parts by weight of hydroxypropyl methacrylate and 36.5 parts by weight of diphenylethylene. The feed rates were chosen such that feed 2 was completely metered in after 3 hours, while feed 1 was only metered in completely after 3.5 hours. After the feeds had ended, the reaction mixture was post-polymerized at 90 ° C. for 30 minutes. The resulting dispersion had a solids content of 26.1% by weight.

example 1 The production of a coating material based on the silane of the general formula la and a clearcoat therefrom

1.08 parts by weight of deionized water, 3.0 parts by weight of glacial acetic acid and 25 parts by weight of 0.1 N acetic acid were placed in a reaction vessel equipped with a dropping funnel and stirrer. 32.1 parts by weight of the silane from Preparation 1 were slowly added to the mixture while stirring. The resulting mixture was stirred at room temperature for 12 hours. The resulting coating material was knife-coated onto a glass sheet and the resulting layer was cured at 140 ° C. for 22 minutes.

The clearcoat obtained in this way had a dry layer thickness of 15 μm. It was free from stress cracks and other surface defects. It was also exceptionally scratch-resistant, which was confirmed by the steel wool scratch test (grade 1 - 2).

A hammer according to DIN 1041 (weight without handle: 800 g; handle length: 35 cm) was used to carry out the steel wool scratch test. The test panels were stored at room temperature for 24 hours prior to testing.

The flat side of the hammer was covered with a layer of steel wool and attached to the folded-up sides with tape. The hammer was placed on the clear coats at a right angle. The weight of the hammer was guided in a track over the surface of the clearcoat without being jammed and without additional physical strength. In each test, 10 double strokes were carried out by hand. The steel wool was replaced after each of these individual tests.

After the load, the test areas were cleaned of the steel wool residues with a soft cloth. The test areas were visually evaluated under artificial light and graded as follows:

Note damage pattern

1 not available

2 low

3 moderate

4 moderate to medium

5 strong

6 very strong

The evaluation was carried out immediately after the end of the test.

Example 2

The production of a coating material based on the silane of the general formula Ib and a clearcoat therefrom

0.5 part by weight of deionized water, 6.3 parts by weight of 0.1 N acetic acid and 0.75 part by weight of glacial acetic acid were placed in a reaction vessel equipped with a dropping funnel and stirrer. 14.5 parts by weight of the silane Ib from Preparation Example 2 were slowly added to the mixture with stirring. The cloudy reaction mixture thus obtained was stirred at room temperature for five hours. After only four hours the mixture began to clear up; after five hours it was completely transparent. The resulting coating material was knife-coated onto a glass sheet and the resulting layer was cured at 140 ° C. for 22 minutes.

The clearcoat had a dry film thickness of 20 μm. It was free from tension cracks and other surface defects. The scratch resistance was very good, which could be demonstrated by the Steinwölle scratch test; the grade was 2.

The so-called acid resistance was tested with the help of the BART.

The BART (BASF ACID RESISTANCE TEST) was used to determine the resistance of the clear coat to acids, alkalis and water drops. The clearcoat on a gradient oven was subjected to a further temperature load after baking for 30 min at 40 ° C. Previously, the test substances (sulfuric acid 10%, 36%; sulfuric acid 6%, hydrochloric acid 10%, sodium hydroxide solution 5%, VE (= fully desalinated or deionized) water 1, 2, 3 or 4 drops) applied with a pipette. Following exposure to the substances, they were removed under running water and the damage was assessed visually after 24 hours on a predefined scale:

Grading appearance

0 no defect

1 light marking

2 Marking / matting / no softening 3 MarkingΛ matting / color change / softening

4 cracks / beginning to etch through 5 clear coat removed

Each individual marking (spot) was evaluated and the result recorded in the form of a grade for each test substance:

Test substance grade

10% sulfuric acid 0

36% sulfuric acid 0

Hydrochloric acid 10% 1 Sulphurous acid 6% 0

Sodium hydroxide solution 5% 0

Demineralized water 0

The clearcoat therefore had very good acid resistance.

The chemical resistance of the clear coat was determined using the gradient oven test. For this purpose, the coating material was applied to a basecoat on a test panel and cured at 140 ° C. for 22 minutes. The resulting clearcoat was exposed to test substances and the temperatures at which the test substances began to damage the clearcoat were determined. The following results resulted:

Tree resin> 75 ° C

NaOH 50 ° C

Pancreatin 72 ° C

43 ° C deionized water> 75 ° C

Accordingly, the clear coat had one _. very good chemical resistance. Comparative experiments V 1 to V 3

The production of coating materials based on epoxy-functional silanes and clear coats from them

1.08 parts by weight of deionized water, 3.0 parts by weight of glacial acetic acid and 25 parts by weight of 0.1 N acetic acid were placed in three reaction vessels equipped with a dropping funnel and stirrer. The blends were slowly adding

Comparative experiment V 1 with 23.6 parts by weight of glycidyloxypropyltrimethoxysilane,

Comparative experiment V 2 with 27.8 parts by weight of glycidyloxypropyltriethoxysilane and

Comparative experiment V 3 with 28.8 parts by weight of 2- (3,4-epoxycyclohexyl) ethyltriethoxysilane

added and stirred for a further 12 hours at room temperature. The resulting coating materials were knife-coated on glass plates and the resulting layers were cured at 140 ° C. for 22 minutes.

The resulting clearcoats had a dry film thickness of 15 μm. However, their surfaces were soft and showed properties of an uncrosslinked or only slightly crosslinked film. Larger defects in the clearcoats could be created by just gently pressing with a fingernail. The scratch resistance of the clearcoats was poor (grade 6 in the steel wool scratch test). Comparative experiment V 4

The production of a coating material based on an epoxy-functional silane and a clear coat from it

10 parts by weight of glacial acetic acid and 15 parts by weight of 0.1 N acetic acid were placed in a reaction vessel equipped with a dropping funnel and stirrer. The mixture was slowly mixed with 52.48 parts by weight of 5,6-epoxyhexyltriethoxysilane and stirred for a further 12 hours at room temperature. The resulting coating material was knife-coated onto a glass sheet and the resulting layer was cured at 140 ° C. for 22 minutes.

The resulting clearcoat had a dry film thickness of 15 μm. However, their surface was soft and showed properties of a non-cross-linked or only slightly cross-linked film. Larger defects in the clearcoat could be created by simply pressing with a fingernail. The scratch resistance of the clearcoat was poor (grade 6 in the steel wool scratch test).

Example 3

The production of a coating material based on a condensate of a silane of the general formula Ia and a binder and a clearcoat therefrom

133 parts by weight of the coating material of preparation example 1 were added to 35 parts by weight of the binder dispersion of preparation example 3. The resulting coating material was left for 2 hours stirred at room temperature. It was completely stable in storage for 6 days; no increase in viscosity could be found during this time.

The coating material was knife-coated onto a glass sheet. The resulting layer was cured at 140 ° C for 22 minutes.

The resulting clear coat was high gloss (> 80 units at 20 °), clear and transparent. Their dry layer thickness was 40 μm. It was free from stress cracks and surface defects. The scratch resistance was excellent (grade 1 - 2 in the steel wool scratch test).

Comparative experiments V 5 and V 6

Production of coating materials based on condensates epoxy-functional Siiane and binders as well as clear coats from them

Example 3 was repeated, except that instead of the coating material of example 1

in comparison test V 5, the coating material of comparison test V 1 and

in comparative experiment V 6, the coating material of comparative experiment V 2

was used.

The resulting coating materials were knife-coated on glass plates and the resulting layers were cured at 140 ° C. for 22 minutes. The resulting clear coats had a dry film thickness of 40 μm. Their surfaces were soft and showed properties of a non-cross-linked or only slightly cross-linked film. Larger defects in the clearcoats could be created by just gently pressing with a fingernail. The scratch resistance of the clearcoats was poor (grade 6 in the steel wool scratch test).

Comparative experiment V 7

The production of a coating material based on the condensate of an epoxy-functional silane, a binder and an external catalyst

2.78 parts by weight of boehmite (Disperal® P 3 from Sasol Germany GmbH) were added to 25 parts by weight of 0.1 N acetic acid. The resulting mixture was stirred at room temperature until the boehmite was completely dissolved. The colloidal solution was then treated with ultrasound for 5 minutes.

27.8 parts by weight of glycidyloxypropyltriethoxysilane were added to the resulting homogeneous boehmite sol. The mixture thus obtained was stirred at room temperature for 12 hours.

133 parts by weight of this mixture were mixed with 35 parts by weight of the binder dispersion of preparation example 3. The resulting coating material was stirred at room temperature for 10 minutes. In this short time there was a drastic increase in viscosity. The coating material was completely gelled after only 2 to 4 hours. An application of the fresh coating material 10 minutes after its production on a glass board and curing the resulting layer for 22 minutes at 140 ° C provided a scratch-resistant, transparent clearcoat that had surface defects and specks.

Claims

claims

1. Autocatalyzed, thermally curable compositions free from external catalysts, comprising at least one condensate of at least one silane selected from the group of Siiane, comprising at least one hydrolyzable atom and / or a hydrolyzable group and

Epoxy group and at least one non-hydrolyzable, epoxy group-free group with at least one group selected from the group consisting of

(a) double-bonded, copper-bonding urethane groups -NH-

C (X) -X- and -X- (X) C-NH-,

(b) double-bonded, copper-forming urea groups -HN- C (X) -NH- and

(c) monovalent terminal groups Y-C (X) -NH-,

(iii) at least one non-hydrolyzable, isocyanate adduct group-free group with at least one Epoxy group, at least one non-hydrolyzable, epoxy group-free group with at least one group selected from the group consisting of groups (a), (b) and (c), and at least one non-hydrolyzable group with at least one epoxy group and at least one group, selected from the group consisting of groups (a), (b) and (c).

2. Thermally curable compositions according to claim 1, characterized in that the blocking agents from the group consisting of phenols, lactams, active methylene compounds, alcohols, mercaptans, acid amides, imides, amines, imidazoles, ureas, carbamates, imines, oximes, salts the sulfurous acid, hydroxamic acid esters, substituted pyrazoles and triazoles, and mixtures of these

Blocking agents can be selected.

3. Thermally curable compositions according to claim 1 or 2, characterized in that the silane from the group consisting of silanes of the general formulas la:

Z _m SiR „R ¹ ₀ (la),

where the indices and the variables of formula la are the following

Have meaning:

Z hydrolyzable, non-isocyanate-reactive atom and / or hydrolyzable, monovalent, non-isocyanate-reactive group; R non-hydrolyzable, single-bonded organic group containing at least one epoxy group;

R ¹ non-hydrolyzable, single-bonded organic group, containing no epoxy group;

m 1, 2 or 3;

n 1, 2 or 3; and

o 0, 1 or 2;

with the proviso that m + n + o = 4; and

from silanes of the general formula Ib:

(Z _m R ¹ ₀ Si) _p R ² (Ib),

with the proviso that at least one group R and / or R ^{1 of} the general formula la and at least one group R1 and / or R2 of the general formula Ib have at least one group selected from the group consisting of groups (a), (b ) and (c), contains; is selected.

4. Thermally curable compositions according to claim 3, characterized in that the indices m, n and o in the formula la have the following meaning: m = 3, n = 1 and o = 0; and the indices m, o and p in the general formula Ib have the following meaning: m = 3, o = 0 and p = 2.

5. Thermally curable compositions according to claim 3 or 4, characterized in that the hydrolyzable, non-isocyanate-reactive

Atom Z is selected from the group consisting of fluorine atoms, chlorine atoms and bromine atoms, and the hydrolyzable, monovalent, non-isocyanate-reactive group Z is selected from the group consisting of monovalent organic groups.

Thermally curable compositions according to claim 5, characterized in that the hydrolyzable, monovalent, non-isocyanate-reactive organic group Z is an alkoxy group having 1 to 4 carbon atoms in the alkyl radical.

7. Thermally curable compositions according to one of claims 3 to 6, characterized in that the non-hydrolyzable, single-bonded organic group R, containing at least one epoxy group, and the non-hydrolyzable, multi-bonded organic group R ² from the group consisting of alkyl, alkenyl -, alkynyl, aryl,

Arylalkyl, alkylaryl, arylalkenyl, alkenylaryl, arylalkynyl or alkynylaryl groups, where the alkyl, alkenyl and alkynyl groups can also be cyclic.

8. Thermally curable compositions according to claim 6, characterized in that the groups R and R ² from the group consisting of alkyl groups and alkylcycloalkyl groups.

9. Thermally curable compositions according to one of claims 3 to 8, characterized in that the groups R and R ² contain at least one terminal epoxy group.

10. Thermally curable compositions according to one of claims 3 to 9, characterized in that the groups R and R ² contain an epoxy group.

11. Thermally curable compositions according to one of claims 3 to 10, characterized in that the non-hydrolyzable, monovalent, organic group R ¹ , containing no epoxy group, from the group consisting of alkyl, alkenyl, alkynyl, aryl,

12. Thermally curable compositions according to one of claims 3 to 11, characterized in that the groups R and R ² contain at least one group selected from the group consisting of groups (a), (b) and (c).

13. Thermally curable compositions according to one of claims 1 to 12, characterized in that X = oxygen atom.

14. Thermally curable compositions according to one of claims 1 to 13, characterized in that they contain at least one modifier.

15. Thermally curable compositions according to claim 14, characterized in that the modifier is selected from the group of binders.

16. Use of the thermally curable compositions according to one of claims 1 to 15 for the production of thermally hardened compositions.

17. Use according to claim 16, characterized in that the thermally hardened masses coatings, paints,

Molded parts, in particular optical molded parts, and self-supporting films.

18. Use according to claim 17, characterized in that the coatings, lacquers and self-supporting foils

Protect surfaces of substrates from damage caused by mechanical action and / or for their decoration.

19. Use according to claim 18, characterized in that the substrates are means of transportation or parts thereof, structures, furniture, windows and doors, small industrial parts, coils, containers, packaging, white goods, foils, optical components, electrical components, mechanical components and hollow glass bodies.

20. A method for producing thermally hardened masses from thermally hardenable masses based on condensates epoxyfunctionelier Siiane, characterized in that at least one thermally hardenable mass according to one of the Claims 1 to 15 thermally cured in the absence of external catalysts.