WO1998002478A2

WO1998002478A2 - Water-thinnable, single-component epoxy resin systems with latent hardening

Info

Publication number: WO1998002478A2
Application number: PCT/EP1997/003539
Authority: WO
Inventors: Uwe Neumann; Claus Godau; Theo Emig; Norbert Brunn
Original assignee: Vianova Resins Gmbh
Priority date: 1996-07-13
Filing date: 1997-07-04
Publication date: 1998-01-22
Also published as: WO1998002478A3; DE19628309A1

Abstract

Water-free, water-thinnable, single-component epoxy resin-hardener mixture, characterized by the use of an amine hardener whose amino groups are blocked by a reaction with a carbonyl compound, and are released by a reaction with water, thereupon triggering the hardening reaction.

Description

Water-dilutable, one-component epoxy resin systems with latent curing

Water-thinnable two-component ("2K") epoxy resin systems have become increasingly important among the cold-hardening "water-based paints" (ie paints that are water-thinnable and are solvent-free or only contain small amounts of solvents).

The properties of systems, such as good adhesion to a large number of substrates, excellent corrosion protection and excellent chemical resistance, are on a par with conventional (solvent-containing) epoxy systems.The disadvantage is the constraint of the two-component formulation, namely in epoxy resin and amine hardener, which is only immediately available mixed during processing, with the risk for the user not to maintain the optimal mixing ratio

Conventional systems are known from the prior art which consist of a combination of ketimines and epoxy resins, the latter either being in liquid form or as solid resins dissolved in solvent. The ketimines are cured by cleavage

Air humidity The disadvantages of such systems are obvious. The hardening takes place initially on the surface of the coating and continues to slow down towards the substrate. The surface hardening also prevents the subsequent diffusion of moisture into the interior of the coating, which means that curing is required in addition to the longer diffusion path - together there is insufficient networking with all its side effects, such as worse

Resistance to chemicals, insufficient corrosion protection and poor surface properties, such as gluing. White tarnishing and too little hardness No crosslinking takes place at all below a certain relative humidity. Such systems have been described, for example, in 1967 by Roy T Holm in Journal of Paint Technology, Vol 39, No 509, S 385 and the following patents US-A 3,442,856, US-A 3,919, 17, US-A

4, 148,950, US-A 4,391,958 and US-A 4,748,083 and WO-A 92/18575

The object of the present invention was therefore to develop a component, water-thinnable epoxy resin system, the curing of which does not depend on the air humidity, without the good properties of a two-component epoxy resin system, such as good ones Chemical resistance, high gloss, high final hardness, good scratch resistance, etc. to lose. The task was solved by combining a water-dilutable, liquid epoxy resin with ketone-blocked amines, so-called ketimines

The subject of this invention is therefore an anhydrous water-dilutable one-component

Epoxy resin-hardener mixture, characterized in that an amine hardener is used as the hardener, the amino groups of which are blocked by reaction with a carbonyl compound and are released when water is added and then trigger the hardening reaction.

When water is added, the ketimine is decomposed, the amine hardener is regenerated and is available for hardening. Since the system is water-emulsifiable, an aqueous binder is produced, the processing and properties of which are known to the user via the two-component, aqueous systems. This binder allows the consumer easier processing because the binder is already available in the correct ratio of hardener to epoxy resin. The hardening reaction is started with the addition of water. To achieve the optimal properties of the coating, only a minimum amount of water has to be added.

The epoxy resins can be in pure form or modified by suitable additives. Such additives are, for example, reactive diluents, ie substances which are mixed with

Epoxy resins lower their viscosity, but they are chemically incorporated into the crosslinked resin during the hardening process. Low molecular weight mono- or diepoxides are usually chosen as reactive diluents. Other modifiers are alcohols, preferably non-volatile alcohols such as 3-phenylpropanol, benzyl alcohol or phenylathanol. The epoxy resins can also be mixed with other resins, resins which do not contain any groups which are reactive towards epoxy groups being preferred. Suitable resins are therefore, for example, hydrocarbon resins such as cyclopentadiene resins or coumarone indene resins. The epoxy resin is preferably modified by adding or chemically incorporating emulsifiers in such a way that the epoxy resin-hardener mixture can be water-diluted. Preferred emulsified epoxy resins are therefore both externally emulsified and self-emulsified Third-party emulsified systems are well known as prior art (DE-A 27 26 269, EP-A 0 491 550, DE-A 41 37 590). For example, reactive A / F liquid resins (derived from mixtures of bisphenol A and bisphenol F ) used in combination with non-ionic emulsifiers

Suitable externally emulsified epoxy resins are obtained by adding proportions by mass (based on the mass of the epoxy resin) of 1 to 30% of at least one emulsifier, selected from reaction products of alkylated hydroxyaromatics with 2 to 20 carbon atoms in the alkyl group and at least one aromatically bound hydroxyl group, the aromatic molecular part thereof is selected from benzene and naphthalene bodies and from two or more

Benzene cores, which are linked via a single bond, an alkylene group with 1 to 5 carbon atoms, an ether, carbonyl, sulfone, thioather or carbonamide bridge, and cyclic alkylene oxides selected from ethylene and propylene oxide, with an aromatically bound hydroxyl group 2 to 80 mol of the alkylene oxide can be used individually or in a mixture. Combinations of the nonionic emulsifiers and epoxy resins described below can be used as externally emulsified epoxy resins for the systems described in this patent. In particular, for example, are suitable

Nonylphenol or octylphenol, in the (amount) ratio 1 4 to 1 ^* 50 reacted with oxirane - fatty alcohols, in the ratio 1 5 to 1 100 with oxirane

Fatty acid mono- or diathanolamides, reacted in a ratio of 1 2 to 1 20 with oxirane

Fatty acids, fatty acid mono- or diglycerides or sorbitan esters, in a ratio of 1 2 to

1 100 reacted with oxirane

Suitable fatty acids in the emulsifiers described above are all unbranched, saturated or mono- to tri-unsaturated alkane monocarboxylic acids with a terminal acid group and with 8 to 30 carbon atoms

Suitable fatty alcohols are those which arise from the fatty acids described above by reducing the acid group The emulsifiers described above are mixed individually or in a mixture with the epoxy resin, in a mass ratio of epoxy resin to emulsifier mixture of 99: 1 to 70: 30, preferably 98: 2 to 80: 20.

The suitable epoxy resins are preferably mono-, di- or polyglycidyl ethers or esters of the following alcohols, phenols or acids: 1-butanol, 2-ethylhexanol-1, fatty alcohols with 8 to 22 carbon atoms, 1, 4-butanediol, neo pentylglycol, 1,6-hexanediol and polypropylene glycol with a weight-average molar mass of 200 to 2,000 g / mol,

Phenol, cresol, resorcinol, 2,2-bis (4-hydroxyphenyl) propane, bis (hydroxyphenyl) methane, 4- (4-hydroxyphenyl) phenol, novolaks from phenol or cresol and formaldehyde with a weight-average molar mass M ,, from 200 to 2,000 g / mol and bis (4-hydroxyphenyl) sulfone,

branched monocarboxylic acids which are obtained from olefins by the Koch method and which are sold under the trade name © Versatic acids (Shell Chemicals).

The epoxy compounds described above can be used individually or as a mixture as an epoxy resin mixture.

Self-emulsifying liquid epoxy resins are those which are modified in a self-emulsifying manner by incorporating hydrophilic nonionic groups selected from polyoxyalkylene units with 2 to 4 carbon atoms in the alkylene group and a weight-average molar mass of 200 to 20,000 g mol. They can be made from an epoxy-functional emulsifier and an epoxy resin. The epoxy compounds described above, individually or in a mixture, are suitable as epoxy resin. The epoxy resin is mixed with the emulsifier in a mass ratio of 99: 1 to 70: 1, preferably 98: 1 to 80:20. The emulsifier can be prepared from the glycidyl ethers of the abovementioned alcohols and / or phenols and mono- or polyhydroxy polyethers. The following are possible: semi-etherified polyhydroxy-polyather (polyoxyalkylene glycols) obtained from the reaction of methanol, ethanol, isopropanol, 1-butanol, glycine, trimethylolpropane, pentaerythritol, on the one hand, and oxirane or else a mixture of oxirane and methyloxirane, on the other hand, with a weight-average molar mass M "of 200 to 20,000 g / mol as well as unsaturated polyhydroxy polyethers (polyoxyalkylene glycols), which result from the reaction of 1,2-ethylene glycol,

1,2-propylene glycol, water or aqueous acids or alkalis with oxirane or a mixture of oxirane and methyloxirane are accessible, with a weight average molar mass H _v of 200 to 20,000 g / mol.

In all cases, the polyoxyalkylene glycols preferably contain at least 20% by weight of oxyathylene groups, based on the mass of all polyoxyalkylene groups

The glycidyl ether is reacted with the polyoxyalkylene glycol using a suitable catalyst and a suitable process in the molar ratio of glycidyl ether to polyoxyalkylene glycol from 3.0 1.0 to 7.0 1.0. This process is described in detail in DE-A 43 10 198, EP-A 0 618 245, US-A 4,419,467 and EP-A 0 493 916.

Further self-emulsifying epoxy liquid resins are produced by reacting α-2-aminopropyl-ω-methyl-diathem of oxirane / methyloxirane polymers, which are sold, for example, under the trade name © Jeffamine by Huntsman Corporation Belgium NV (Belgium), and an excess of an epoxy compound, as described above, with at least two epoxy groups per molecule and an epoxy group content of 500 to 10,000 mmol / kg ("epoxide equivalent weight" = weight-average molar mass M _vv divided by the average number of epoxy groups per molecule of 100 up to 2,000 g mol) These resins are described for example in the patents US-A 5,025, 100 and EP-A 0 387 418 (there as a precursor)

The ketimines are preferably prepared from organic compounds with two or more primary amino groups and aliphatic linear, branched or cyclic carbonyl compounds, preferably ketones. A diamine or polyamine is reacted with at least one carboxyl compound in each case. The amine hardeners used to form Schiff's Bases are implemented are selected from aliphatic linear, branched and cyclic amines with at least two primary amino groups, primary polyoxyalkylene diamines with 2 to 4 carbon atoms in the alkylene group, wherein different alkylene groups can also be mixed; not, partially or fully hydrogenated condensation products of aniline or its derivatives toluidine and cresidine with formaldehyde, acetaldehyde or

Acetone, individually or as a mixture; as well as polyamidoamines with at least two terminal primary amino groups from aliphatic linear, branched and cyclic amines with at least two primary amino groups and dicarboxylic acids

Examples of suitable amines are: 2,2,4- and / or 2,4,4-trimethylhexamethylene diamine,

Neopentanediamine, 2-methyl-l, 5-pentanediamine, 1,3-diaminopentane, hexamethylene diamine and others, as well as cycloaliphatic amines such as 1,2- or 1,3-diaminocyclohexane, l, 4-diamino-3,6-diethylcyclohexane, l , 2-diamino-4-ethylcyclohexane, 1,4-diamino-3,6-diathylcyclohexane, 1-cyclohexyl-3,4-diaminocyclohexane, isophoronediamine and reaction products thereof, bis (4-aminocyclohexyl) methane and propane, 3, 3'-dimethyl-4,4'-diaminodicyclohexylmethane, 1, 3- and l, 4-bis (aminomethyl) cyclohexane, and 1,3- and l, 4-bis (aminomethyl) benzene

Oligomeric or polymeric amines are also suitable, for example bis-α, ω-2-aminopropyl ether from Oxiran / Methyloxiran-Poliymeren from Huntsman, which are sold under the trade name en ®Jeffamine, cyclic polyamines which partial hydrogenation of

Formaldehyde-aniline polycondensates are produced and sold under the name ®Ancamine 2168 by Anchor Chemical Limited, Manchester, UK, as well as polyamidoamines which are produced from the above-mentioned diamines and dicarboxylic acids selected from linear and branched aliphatic dicarboxylic acids with 4 to 40 Carbon atoms, phthalic acid, iso- and terephthalic acids and the isomeric 1,2-, 2,3-, 1, 4-, 1, 5-, 1, 8- and 2,6-naphthalenedicarboxylic acids. Examples of the aliphatic dicarboxylic acids are succinic acid, dodecenylsuccinic acid, adipic acid, 2,2,4-Trimethyladipinsaure, 2,4,4-glutaric acid, pimelic acid, suberic acid, azelaic acid, Suberinsaure, Seb acinsaure ^', dodecanedioic acid or so-called dimeric fatty acids, which are produced by dimerization from naturally occurring unsaturated fatty acids. Suitable polyamidoamines are also those at in which proportions of at least 5% of the diamines and dicarboxylic acids have been replaced by aminocarboxylic acids

The above carboxylic acids can be used individually or in a mixture. The amines mentioned can be used alone or as mixtures.

At least one carbonyl compound, preferably at least one ketone, is used in the conversion of the amine to the Schiff base. Examples of ketones with the above

Amines converted to ketimines are: acetone, butanone, 2-pentanone, 3-pentanone, 4-methyl-2-pentanone, cyclopentanone, cyclohexanone, 2-methylcyclohexanone, isopropylmethyl ketone, ethyl isopropyl ketone, 2-hexanone, 3-hexanone, 2-heptanone, 3-heptanone, 4-heptanone, 2-octanone, 3-octanone, 4-octanone, diisopropyl ketone, diisobutyl ketone, 5-ethyl nononanone-2, methyl isobutyl ketone and methyl isoamyl ketone.

The production of such ketimines has been known and described since Schiff (Ann. 1 1, p. 118 (1864)). More recent manufacturing regulations can be found in the above-mentioned patents and in US-A 4,391,958, DE-A 33 25 061, DE-A 34 44 1 10, EP-A 0 240 083, and in the publication by Yang, C -P , Lee, L.-T., Journal of Polymer Science, Part A, Vol. 28, p. 1861

- 1874. The essence of this reference can be summarized as follows: the amine is mixed with an excess of ketone and an acidic catalyst. With the removal of water, the mixture is heated under reflux at normal pressure until the theoretical amount of water has been discharged. Acidic catalysts used for this purpose are: organic mono-, di- and polycarboxylic acids with 1 to 40 carbon atoms, organic sulfonic and

Phosphonic acids and inorganic acids such as, for example, p-toluenesulfonic acid, naphthalenesulfonic acid, oxalic acid, boric acid, phosphoric acid, sulfuric acid, acetic acid, formic acid, propionic acid, citric acid, higher (also unsaturated) fatty acid, dimeric fatty acid, trifluorosulfonic acid in a mass of methanesulfonic acid, a methanesulfonic acid in a mass 0.001 to 5.0% based on the sum of the masses of amine and ketone The ratio of

The number of primary amino groups to ketone groups is from 1.0 to 1.0 to 1.0 to 5.0. A quantitative conversion of the amino groups to the corresponding Schiff base (ketimine), preferably at least 90% of the amino groups, particularly preferably at least 95%, is necessary because a residual portion of free amino groups react with the epoxy groups of the resin and lead to an inevitable increase in the viscosity of the binder Such a binder would not be stable in storage. The effective discharge of water and thus the

The conversion of the reaction depends on the solubility of the water in the refluxing ketone. Depending on the ketone, mass fractions of 1.0% (methyl isobutyl ketone) to 12% (butanone) water are dissolved in the refluxing ketone. We have found that when using aliphatic and / or aromatic hydrocarbons in a mixture with the amines and ketones, the water discharge takes place more thoroughly and also more quickly

As aliphatic and aromatic hydrocarbons, all hydrocarbons with a boiling temperature at normal pressure above 50 ° C and a melting temperature below 20 ° C, which form an azeotrope with water such as hexane, cyclohexane, petroleum ether, ligrom, toluene, xylene, ®Shellsol types (manufacturer Shell Chemicals), and ®Solvesso types

(Manufacturer Esso AG) (both are hydrocarbon distillation cuts that occur during the distillation of petroleum), as well as tetrahydronaphthane and decalin. The mass ratio of hydrocarbon (-gemιsch) to ketone is from 0, 1 to 1, 0 to 10 , 0 to 1.0

In addition to the formation of ketimine, aldol condensation also takes place in the presence of acidic catalysts, in which water is formed. Discharge of the theoretical amount of water can thus replace complete conversion to ketimine the reaction of ketimine formation, distilled out to take this into account. Then the entrainer and excess ketone are distilled off at normal pressure, followed by vacuum distillation at a maximum pressure of 1 to 8 kPa (10 to 80 mbar) and a temperature of 100 to 180 ° C a further option to block any remaining free amino groups, the reaction of the unreacted to ketimine amino groups with monofunctional reactive thinners at 80 to 120 ^C C, after distilling off the solvent Based on the origin - The amount of amine hydrogen (NH) present is exposed to up to 0.2 mol of epoxy the Reaktiwerdunner per 1, 0 mol Amm hydrogen Possible monofunctional reactive thinners. Butylglycidyl ether, phenyl glycidyl ether, cresyl glycidyl ether, monoglycidyl ether of fatty alcohols with 8 to 18 carbon atoms, 2-ethylhexyl glycidyl ether and glycidyl esters of so-called © Versatic acids, which are in the α-position to the carboxylic acid group of the highly branched aliphatic acids, for example, the aliphatic carboxylic acid from aliphatic shell monocarboxylic acids to be expelled.

The procedures described above can be followed individually or in combination with one another.

The ketimine is then ready to be mixed with the water-thinnable liquid resin.

The anhydrous but water-thinnable resins are mixed in a molar ratio of 0.8 to 1.2 mol epoxy groups to 1.0 mol amine hydrogen in the amine to be released. It has been shown that the storage stability of such mixtures can be significantly improved if an alcohol having 1 to 12 carbon atoms or a (poly) oxyalkylene glycol

Monoathers with 1 to 12 carbon atoms in the ether group and 2 to 4 carbon atoms in the oxyalkylene group and a degree of polymerization of 1 to 20, preferably 1 to 4, such as ethanol, isopropanol, 2-butanol, 1-methoxypropanol, benzyl alcohol, di- and triathylene glycol - Monomethylather, butoxyglycol and others admits The choice of these alcohols is determined by their solubility in water and their volatility.The alcohol is soluble in water in a mass fraction of up to 30% The maximum boiling temperature is 200 ° C at normal pressure The optimal mass fraction of alcohol can be up to 20% based on the sum of the masses of epoxy resin and ketimine

Immediately before the application, a (to decompose the ketimine or

A dimins) sufficient amount of water released from the amine hardener. Depending on the reactivity and the ambient temperature, the pot life is up to 24 hours, but at least 2 hours. The typical pot life of these systems is 4 to 12 hours. In addition, a further amount of water can be added, preferably in the mass ratio of water to resin-hardener mixture of 1 20 to 20.1, preferably 1.10 to 10 1, particularly preferably 1: 5 to

5: 1. However, it is also possible, especially on moist substrates and with thin layers, to apply the mixture to the substrate without the addition of water. However, this procedure is unfavorable for dry substrates and low air humidity

The water-thinnable, one-component liquid resin systems according to the invention are used above all as a colorless primer and as a coating agent for pigmented top coating in thin and thick coatings for smooth and porous substrates, in particular for mineral substrates, ie. on plaster, concrete, masonry, screed and in water-diluted form as impregnation for absorbent substrates. They are particularly suitable for fillers and mortar coverings on mineral substrates, for example as modifiers for mineral ones

Putty and screed (cement, anhydrite, magnesite screed) These liquid resin systems are also suitable for the production of coatings on wood, metal (iron and non-ferrous metal) and plastic surfaces

By adding suitable pigments, fillers and additives such as zinc phosphates,

Calcium metaborates and mica can be formulated to protect against corrosion for metallic substrates. For non-absorbent reason, the adhesion can be obtained by addition of ^'special adhesion promoters (promoters) such as silanes can be significantly improved, so that for example primers with excellent adhesion and additionally optionally corrosion protective properties can be formulated These primers can with most known 1K and 2K Deckbeschichtungsmittein be covered

If necessary, the customary thinners, pigments and

Fillers are added

For example, aliphatic alcohols with 1 to 10 carbon atoms such as ethanol, propanol, isopropanol, n-

Butanol, isobutanol, 2-butanol, methoxypropanol, ethoxypropanol, butoxypropanol, araliphatic alcohols such as phenoxyathanol, phenoxypropanol, 1-phenyl-ethanol, 2-phenyl-ethanol, 3-phenyl-propanol, benzyl alcohol and aliphatic diglycidyl ethers such as 1, 4- Butanediol diglycidyl ether, 1, 6-hexanediol diglycidyl ether and diglycidyl ether of polypropylene glycols Suitable pigments and fillers include Silicates such as talc, silicon dioxide in various forms (quartz sand, quartz powder), titanium dioxide, zinc sulfide pigments, gypsum, blanc fixe, iron oxide pigments such as iron oxide black and iron oxide yellow and chrome oxide green.Other suitable fillers are G! As (hollow) balls, plastic - and rubber granules, effect additives such as pearlescent pigments and colored plastic chips

The formulated systems can also be stabilized by adding so-called water catchers. This is understood to mean organic or inorganic substances that react with residual water in the formulation, but also as a preventive measure against contamination with water from the air before use, and remove the water required to split the ketimine from the mixture the nature of the matter that only those substances come into question which do not react with epoxy or ketimine groups

Of organic substances can come into question, for example, - monofunctional isocyanates such as phenyl isocyanate, toluyl isocyanate, 4-isopropyl phenyl isocyanate, 1-naphthyl isocyanate and Stearyhsocyanat easily verseilbare esters such as Kieselsaureester (AJkoxysilane) Oxalsauredialkylester, Brenztraubensaurealkylester, Glykolsaurealkylester, Glyoxalsaurealkylester and Lactic acid alkyl ester, the alkyl group each having 1 to 20 carbon atoms, preferably 1 to 10 carbon atoms

Examples of inorganic substances are silicates, such as (earth) alkali (alumo) silicates and layered silicates, diatomaceous earth, alkaline earth oxides, (earth) alkali sulfates and alums

The following examples are intended to illustrate the invention without restricting its selection

The specific epoxy group content SEC (amount of epoxy groups based on the

Mass of the solid) or its reciprocal (the so-called EV) is determined according to DIN 53 188; the amine number (mass of KOH in mg, which binds as much acid for neutralization as 1 g of the substance in question, based on the mass of the substance in g) according to DIN 16 945 and one Acid number (mass of KOH in mg required to neutralize 1 g of the substance concerned, based on the mass of the substance in g)

Parts or percentages are always parts by mass

EXAMPLES:

1 Emulsifiable liquid resins

1.1 Foreign emulsified, resin 1

A mixture of 910 g © Beckopox EP 1 16 (epoxy resin from Vianova Resins GmbH with a specific epoxy group content of 5560 mmol / kg (epoxy equivalent weight EV of 180 g mol) based on bisphenol A / F), 39 g ®Simulsol M 53 (with 50 mol of ethylene oxide ethoxylated stearic acid, manufacturer Seppic, France), 20 g ®Simulsol 1030 NP (with 10 mol ethylene oxide athoxylated nonylphenol, manufacturer Seppic, France) and 25 g © Octaox 4030 (with 40 mol ethylene oxide, ethoxylated octylphenol, manufacturer Seppic, France) ) are homogenized at 70 ° C

specific epoxy group content 5076 mmol / kg

(Epoxy equivalent 197 g / mol)

Viscosity 800 ιnPa-s / 25 ° C

1.2 Self-insertable, resin 2

A mixture of 70 g © Jeffamine M - 1000, an amino-terminated polyoxyethylene (propylene) monomethyl ether (Huntsman Coφoration Belgium NV) and 930 g © Beckopox EP 140 heated at 120 ° C until the calculated epoxy group content is reached (about four hours). The amine number and an apparent amine number (titration with and without tetrabutylammonium bromide) are measured. The samples are dissolved in glacial acetic acid / acetone (volume ratio 1: 1) and titrated with 0.1N perchloric acid, dissolved in glacial acetic acid. The specific epoxy group content SEC in mmol / kg or the "epoxy equivalent weight" (EV) in g / mol is found using the following formula:

SEC (AZ (ra- 1 AZ {ch → z / mg g mmol kg 0.0511

EV 56 110 mg g ^" - ^* g mol (AZ, (mi" CI, - AZ, l without ",

in which

AZ _(mi) means: amine number on titration with an excess of tetrabutylammonium bromide.

AZ _(without) means amine number for titration without tetrabutylammonium bromide

specific epoxy group content 5025 mmol / kg (epoxide equivalent weight 199 g / mol)

Viscosity ^* 7400 mPa-s / 25 ° C

1.3 Self-emulsifiable, resin 3

389 g of a diglycidyl ether of bisphenol A with a specific epoxide group content of 5405 mmol / kg (an EV value of 185 g / mol, © Beckopox EP 140 from Vianova Resins GmbH) are heated to 125 ° C. with 31 1 g of polyethylene glycol with an average molar mass of 2000 g / mol in a nitrogen atmosphere. While stirring well, 1.5 g of a BF ₃ amine complex are added as a catalyst (© Anchor 1040 from Anchor).

During four hours, the temperature is continuously increased to 150 ° C. The specific

Epoxy group content is now 2380 to 2410 mmol / kg (EV 415 to 420 g / mol). The mixture solidifies to a waxy, crystalline mass at room temperature

175 g of bisphenol F diglycidyl ether with a specific epoxide group content of 5710 to 6061 mmol / kg (EV 165 to 175, Epikote® 862, Shell Chemicals) and 325 g of bisphenol A diglycidyl ether (Beckopox® EP 140, Vianova Resins GmbH) homogenized at room temperature. 68.2 g of the abovementioned emulsifier (12% based on total mass) are added to the homogeneous mixture. The mixture is homogenized at 70 ° C. for two hours under nitrogen.

specific epoxy group content: 5128 mmol / kg

(Epoxy equivalent weight ^* 195 g / mol)

Viscosity: 4,800 mPa-s / 25 ° C

2 ketimines

2.1 Ketimine example 1

238 g ®Laromin C 260 (bis (4-amino-3-methyl-cyclohexyl) methane from BASF), 200 g

Xylene and 258 g of 3-pentanone are heated with 1.0 g of p-toluenesulfonic acid at atmospheric pressure with the removal of water. After the theoretically determined amount of water of reaction has been separated off, the solvent mixture is distilled first at atmospheric pressure and then under reduced pressure at 5 kPa (50 mbar) From then hold at 130 ° C and 5 kPa (50 mbar) for 60 minutes. Amine number 298 mg / g

Viscosity. 350 mPa s / 25 ° C specific amine hydrogen content 10.64 mmol / g

(N-H equivalent. 94 g / mol)

2.1 Ketimine example 2

284 g of PACM® (bis- (4-aminocyclohexyl) methane from Anchor), 284 g of cyclohexane and 284 g of butanone are heated with 1.6 g of boric acid at atmospheric pressure with the removal of water. After the theoretically determined amount of water of reaction has been separated off, the solvent mixture is distilled first at normal pressure, then at reduced pressure at 5 kPa (50 mbar). Then the mixture is held at 130 ° C. and 5 kPa (50 mbar) for 60 minutes. Then the boric acid is filtered off After cooling to 80 ° C., 15 g of cresyl glycidyl ether (specific epoxide group content 5525 mmol / kg, EV value 181 g / mol) are added. The temperature is increased to 120 ° C. and left for two hours

Amine number 353 mg / g

Viscosity. 1 250 mPa-s / 25 ° C specific amine hydrogen content 12.35 mmol / g

(N-H equivalent 81 g / mol)

2.1 Ketimine example 3

286 gl, 3-bis (aminomethyl) benzene and 571 g Pripol® 1009 (dimeric fatty acid from Unichema, acid number 206 mg / g, viscosity 7,500 mPa * s at 25 ° C) are gradually increased from room temperature in two hours Heated 165 ° C, water of reaction is distilled off Then this temperature is maintained for one hour, then heated to 200 ° C and held at this temperature for a further hour. Finally, the temperature is raised to 230 ° C and the amine number is maintained for 2 hours is then 151 mg / g and the acid number is 1.6 mg / g This polyamidoamine is then mixed with 374 g of 3-pentanone and 374 g of cyclohexane and heated at normal pressure with water being removed. After separating 105% of the theoretically determined amount of water of reaction, the solvent mixture is first distilled at normal pressure, then in vacuo at 5 kPa (50 mbar). After cooling to 80 ° C., 40 g of cresylglycidyl ether (specific epoxy group content 5464 mmol / kg; EV value

183 g / mol) added. The temperature is raised to 120 ° C and left for two hours.

Amine number: 120 mg / g

Viscosity: 21 Pa * s / 25 ° C specific amine hydrogen content 4.05 mmol / g

(N-H equivalent: 247 g / mol)

2.1 Ketimine example 4

1.70 g of isophoronediamine, 200 g of xylene and 258 g of 3-pentanone are heated with 1.0 g of p-toluenesulfonic acid at atmospheric pressure with the removal of water. After separating 105% of the theoretically determined amount of water of reaction, the mixture is first distilled at atmospheric pressure, then the solvent mixture at reduced pressure at 5 kPa (50 mbar). The mixture is then held at 130 ° C. and 5 kPa (50 mbar) for 60 minutes

Amine number: 370 mg / g

Viscosity: 250 mPa-s / 25 ° C specific amine hydrogen content 13.0 mmol / g (N-H equivalent 77 g / mol)

2.1 Ketimine example 5

216 g Ancamine® X 2168 (partially hydrogenated polymer from aniline and formaldehyde, amine number 480 mg / g, viscosity 50 Pa * s / 40 ° C, from Anchor), 240 g cyclohexane and 310 g 3-

Pentanone are heated with 2.5 g of acetic acid at normal pressure with the removal of water After the theoretically determined amount of water of reaction has been separated off, the solvent mixture is distilled off first under normal pressure, then under reduced pressure at 5 kPa (50 mbar). The mixture is then held at 130 ° C. and 5 kPa (50 mbar) for 60 minutes. After cooling to 80 ° C., 21.8 g of cresyl glycidyl ether (specific epoxy group content 5464 mmol / kg; EV value 183 g / mol) are added . The temperature is then raised to 120 ° C and left for two hours.

Amine number: 303 mg / g

Viscosity (80% in isopropanol) 12,500 mPa-s / 25 ° C specific amine hydrogen content 10.4 mmol / g

(N-H equivalent 96 g / mol)

3 Technical application test 3.1 Formulation

For a pre-call, the system is diluted with water without formulation and applied as a clear coat. A conventional, aqueous epoxy hardener, © Beckopox EH 623w, in the form of an 80% solution in water, which is used for two-component, aqueous systems, serves as a comparison

What stands out is the good water resistance. Remarkable is the rapid increase in pendulum hardness (according to Konig, DIN 53 157) compared to the two-component system (example 8).

The results of the test are summarized in the following table Table 1

oo

IP isopropanol

HV adherence loss, rating 0 best, 5 worst

Table 2

Recipe 1 serves as an example of a non-pigmented primer; recipe 2 applies to an example of a thick layer system (Table 2)

The formulated systems according to Table 1 were hardened without the addition of water. The addition of water additionally accelerated the reaction, so that films with a higher layer thickness were also dry and tack-free after one day. In the case of thin coatings, the addition of water was not absolutely necessary is supported, for example, by adding 50 parts of sand and 10 parts of water to 100 parts of formulation 2. This enables a thick-layered mortar to be produced that is dry and non-sticky in layers up to 1 mm after one day at room temperature

It is advantageous to use raw materials with a minimum of water (residual moisture). In order to stabilize the formulation, additional water scavengers are generally necessary.

By adding suitable catalysts, faster hardening systems are accessible. For example, tertiary amines such as benzyldimethylamine or acids such as salicylic acid and p-toluenesulfonic acid can be used

The above-mentioned recipes can be produced in different ways.For the unpigmented version of recipe 1, all recipe components with the exception of the ketimines can be mixed in a used production container. Depending on the water catcher, the addition of the ketimines takes a few minutes to several days until no free one More water is detected This process can be accelerated considerably by the addition of heat

Another possibility is the use of a vacuum dissolver for production. A water scavenger may also be necessary here, so that after mixing the recipe components with the exception of the ketimines as described above, depending on the water scavenger, the addition of the ketimines may take a few minutes to several days The production of pigmented versions such as formulation 2 can be carried out in the same way as for the unpigmented versions. The pigments and fillers are rubbed in the pure epoxy resin without the ketimines. Alternatively, a pigment paste can be used.

The products produced in this way should be filled with the exclusion of atmospheric moisture. Before closing the container, flushing with dry nitrogen or dry air is advantageous.

The application of the products mentioned can be by pouring, dipping or flooding or by

Use of conventional aids such as brushes, rollers, squeegees, spatulas, compressed air sprayers or airless sprayers. In general, the pigment and filler-containing formulations should be stirred before use. Water should be added while the agitator is running slowly and the material for at least be mixed well for three minutes.

Suitable substrates include wood, all mineral substrates, the known plastics, especially plastics based on polyaddition polymers and metals such as aluminum, aluminum and other light metal alloys, iron, galvanized iron, stainless steel and brass

The curing of the coatings can be waited for at room temperature or accelerated up to 150 ° C by additional heat. Another possibility of accelerating the hardening is the passage through steam-heated drying plants

Claims

claims

1 anhydrous, water-dilutable one-component epoxy resin-hardener mixture, characterized in that an amine hardener is used as the hardener, the amino groups of which are blocked by reaction with a carbonyl compound and are released when water is added and then trigger the hardening reaction

2. An anhydrous, water-dilutable one-component epoxy resin-hardener mixture according to claim 1, characterized in that the epoxy resin is modified by the addition of emulsifiers such that the epoxy resin-hardener mixture is water-thinnable

3. An anhydrous, water-dilutable one-component epoxy resin-hardener mixture according to claim 1, characterized in that the epoxy resin is modified by chemical incorporation of emulsifiers in the epoxy resin in such a way that the epoxy resin-hardener mixture is water-thinnable.

4. An anhydrous, water-dilutable one-component epoxy resin-hardener mixture according to claim 1, characterized in that an organic compound with two or more primary amino groups is used as the amine hardener

5 Water-free, water-dilutable one-component epoxy resin-hardener mixture

Claim 4, characterized in that the aminic hardener is converted into a Schiff base by reaction with at least one carbonyl compound

6. An anhydrous, water-dilutable one-component epoxy resin-hardener mixture according to claim 1, characterized in that at least 90% of the primary amino groups of the amine hardener have been converted into structures of Schiff bases.

7 anhydrous, water-dilutable one-component epoxy resin-hardener mixture according to claim 1, characterized in that the amine hardeners are selected from aliphatic linear, branched and cyclic amines with at least two primary amino groups, primary polyoxyalkylenediamines with 2 to 4 carbon atoms in the alkylene group, although different alkylene groups can also be mixed, non, partially or completely hydrogenated condensation products of aniline or its homologues toluidine and cresidine with formaldehyde, acetaldehyde or acetone, in each case individually or in a mixture, and also Polyamidoamines with at least two terminal primary amino groups from aliphatic linear, branched and cyclic amines with at least two primary amino groups and dicarboxylic acids

8 An anhydrous, water-dilutable one-component epoxy resin-hardener mixture according to claim 7, characterized in that the blocked amines used as hardeners are polyamidoamines in which proportions of at least 5% of the diamines and dicarboxylic acids are replaced by aminocarboxylic acids

9 Anhydrous, water-dilutable one-component epoxy resin-hardener mixture according to claim 7, characterized in that the used for the preparation of the polyamidoamines

Dicarboxylic acids are selected from linear and branched aliphatic dicarboxylic acids with 4 to 40 carbon atoms, phthalic acid, iso- and terephthalic acids and the isomers 1,2-, 2,3-, 1,4-, 1,5-, 1,8- and 2 , 6-Naphthalindιcarbonsauren

10 Water-free, water-dilutable one-component epoxy resin-hardener mixture

Claim 1, characterized in that the epoxy resins are modified in a self-emulsifying manner by incorporating hydrophilic nonionic groups selected from polyoxyalkylene units with 2 to 4 carbon atoms in the alkylene group, a weight-average molar mass of 200 to 20,000 g / mol

1 1 Anhydrous, water-dilutable one-component epoxy resin-hardener mixture according to claim 10, characterized in that the hydrophilic non-ionic groups have a mass fraction of at least 20% of building blocks derived from oxyethylene

12 Anhydrous, water-dilutable one-component epoxy resin-hardener mixture

Claim 10, characterized in that the hydrophilic nonionic groups have one Make up a mass fraction of 1 to 30% of the mass of the self-emulsifying modified epoxy resin

13. An anhydrous, water-dilutable one-component epoxy resin-hardener mixture according to claim 1, characterized in that the epoxy resins are externally emulsified by adding proportions by mass (based on the mass of the epoxy resin) of 1 to 30% of at least one emulsifier selected from reaction products of alkylated hydroxyaromatics with 2 to 20 carbon atoms in the alkyl group and at least one aromatically bound hydroxyl group, the aromatic molecular part of which is selected from benzene and naphthalene bodies and from two or more benzene bodies which have a single bond, an alkylene group with 1 to 5 Carbon atoms, an ether, carbonyl, sulfone, thioather or carbonamide bridges are linked, and cyclic alkylene oxides selected from ethylene and propylene oxide, 2 to 80 mol of the alkylene oxide being used individually or in each case on an aromatically bound hydroxyl group Mixture can be used

14. A method for curing a water-free one-component epoxy resin-hardener mixture according to claim 1, characterized in that a mass fraction of 0.5 to 30% of water, based on the mass of the epoxy resin-hardener mixture for the draw is added to the hardening reaction

15 Anhydrous, water-dilutable one-component epoxy resin-hardener mixture according to claim 1, characterized in that epoxy resin and hardener are present in such quantities that the molar ratio is 0.8 to 1.2 mol epoxy groups to 1.0 mol amine Is hydrogen in the amine to be released

16 anhydrous, water-dilutable one-component epoxy resin-hardener mixture according to claim 1, characterized in that a mass fraction of up to 20%, based on the sum of the masses of epoxy resin and hardener, of an alcohol having 1 to 12 carbon atoms or a ( Poly) oxyalkylene glycol monoather having 1 to 12 carbon atoms in the ether group and 2 to 4 carbon atoms in the oxyalkylene group and a degree of polymerization of 1 to 20 is added

17 coating composition containing an anhydrous, water-dilutable one-component epoxy resin-hardener mixture according to claim 1, water and optionally other conventional additives

18. Coating composition according to claim 17, characterized in that additionally inorganic water scavengers are used selected from silicates, such as (earth) alkali (alumo) silicates and layered silicates, diatomaceous earth, alkaline earth oxides, (earth) alkali sulfates and alum

19 coating agent according to claim 17, characterized in that additional organic water scavengers are used selected from monofunctional isocyanates, such as phenyl isocyanate, toluyl isocyanate, 4-isopropylphenyl isocyanate, 1-naphthyl isocyanate and stearyl isocyanate, easily saponifiable esters, such as silicic acid esters (alkoxysilanes), oxalic acid esters , Pyruvic acid alkyl esters, glycolic acid alkyl esters, glyoxalic acid alkyl esters and lactic acid alkyl esters

20 coatings on porous or smooth substrates, produced with a coating agent according to claim 17

21 spatula and mortar coating for mineral substrates, produced with a coating composition according to claim 17

22 corrosion protection coatings on ferrous and non-ferrous metals, produced with a coating agent according to claim 17

23 modifier for mineral fillers and screeds, selected from cement, anhydrite and magnesite screeds, produced with a coating composition according to claim 17