EP1765904A1

EP1765904A1 - Functionalized, aqueous resins

Info

Publication number: EP1765904A1
Application number: EP05747885A
Authority: EP
Inventors: Werner Andrejewski; Patrick GLÖCKNER; Lutz Mindach
Original assignee: Degussa GmbH
Current assignee: Evonik Operations GmbH
Priority date: 2004-07-15
Filing date: 2005-05-23
Publication date: 2007-03-28
Also published as: BRPI0513339A; CA2573724A1; TNSN07008A1; MX2007000437A; DE102004034303A1; WO2006005644A1; RU2007105542A; CN1918206A

Abstract

Disclosed are aqueous, functionalized resin dispersions obtained by reacting or proportionately reacting A) hydroxy group-containing ketone resins, ketone/aldehyde resins, urea/aldehyde resins, or the hydrogenated resultant products thereof, B) at least one modified isocyanate and/or polyisocyanate which comprises at least one free NCO group and is obtained by reacting at least one isocyanate and/or polyisocyanate with compounds containing at least one hydrophilic group and/or a potentially hydrophilic group in addition to being provided with at least one function that is reactive towards isocyanate groups, and C) at least one compound which is provided with a function reactive to isocyanate groups and contains additional functional groups, whereupon the optionally neutralized resin is mixed with water. Also disclosed is a method for producing said aqueous, functionalized resin dispersions.

Description

Functionalized, aqueous resins

The present invention relates to functionalized, aqueous ketone, ketone / aldehyde or urea / aldehyde resin dispersions and to a process for their preparation.

The condensation to form ketone, ketone / aldehyde and urea-aldehyde resins is known (Ullrnann's Encyclopedia of Industrial Chemistry, VCH Verlagsgesellschaft mbH Weinheim 1993, Vol. 23, pp. 99-105). Such resins are generally water-insoluble.

In DE-OS 25 42 090 sulfo groups carrying water-soluble compounds are described, which are available deviating from the process of the invention in a common condensation reaction of cycloalkanone, formaldehyde and alkali metal bisulfite.

In DE-OS 31 44 673 water-soluble condensation products are listed, which are also obtained by joint reaction of ketones, aldehydes and acid groups introducing compounds. Examples of the latter are sulfites, amidosulfonic acid, aminoacetic acid and phosphorous acid salts.

According to DE-OS 25 42 090 and DE-OS 31 44 673, products containing electrolyte (eg Na ions) are obtained. Such resins, however, deteriorate inter alia the corrosion protection of coating systems.

EP 0 617 103 A1 describes the reaction of polyisocyanates (a) and dihydroxy compounds (b) having a molecular weight of 500 to 5,000 which do not convert groups which can be converted into ionic groups (for example carboxylic acid groups), but other functional groups such as or ether groups (see page 3, lines 17-21). The polyurethane thus obtained is still with a compound (c) which contains in addition to NCO-reactive groups nor a group which can be converted into an ionic group, and optionally with diols or polyols (d) having a molecular weight of 60 to 500, which no further functional Wear groups (see page 4, lines 5 to 15), implemented. Subsequently, this reaction product is reacted with a condensation resin and brought into the water. The the The present invention underlying resins are not mentioned.

DE-OS 2408 865 describes melamine-formaldehyde-polyurethane resins which are water-dilutable or water-dispersible. The base of the polyurethane resin is based on alkyd resin based polycondensation products (see page 2, first paragraph). Alkyd resins are made from carboxylic acids, unsaturated fatty acids, diols and polyols.

DE-OS 34 06 473 and DE-OS 34 06 474 and EP-AO 154 835 describe processes for the preparation of stable aqueous dispersions of urea-ηldehyd resins or ketone / (aldehyde) resins, after which the resin melt or its highly concentrated solution in the presence of organic protective colloids optionally dispersed in water with the addition of emulsifiers. A disadvantage of these processes is the fact that the organic protective colloids and emulsifiers interfere with the application of the aqueous ketone / (aldehyde) or urea / aldehyde resins in the coating sector. The hydrophilic protective colloids and optionally emulsifiers remain in the coating and make them sensitive to moisture. The coating swells when exposed to moisture, loses its hardness and loses its anti-corrosion effect.

Water-dispersible condensation products are described in EP 0 838 486 A1, EP 0 838 485, EP 0498 301, DE 25 42090, DE 31 44 673 and EP 0 154 835. The targeted introduction of tailor-made compounds for further functionalization is not the subject of these applications.

The object of the invention was to develop functionalized ketone, ketone / aldehyde or urea / aldehyde resin dispersions and a process for their preparation. The resin dispersions should be stable to hydrolysis or storage and should not have the disadvantages described above.

The task underlying the invention is surprisingly achieved according to the claims by reacting hydroxygrappenhaltige ketone, ketone / aldehyde, urea / aldehyde resins or their hydrogenated derivatives with hydrophilic modified (poly) isocyanates and, in addition, functional groups will be incorporated into the polymer.

After neutralization and addition of water, the ketone-, ketone-aldehyde-, urea-acid-aldehyde resins of the invention thus modified give stable aqueous solutions, dilutions and dispersions.

The aqueous systems according to the invention are completely resistant to hydrolysis in comparison with the systems already known from the prior art and contain no interfering additives, for example. B. in the form of emulsifiers, protective colloids or electrolytes.

The present invention relates to aqueous resin dispersions, and a process for their preparation obtainable by reaction or proportionate reaction of

A) hydroxyl-containing ketone, ketone / aldehyde, urea-aldehyde resins or their hydrogenated derivatives and

B) at least one modified isocyanate and / or polyisocyanate having at least one free NCO group, obtainable by reacting at least one isocyanate and / or polyisocyanate with compounds which, in addition to the hydrophilic or potentially hydrophilic group at least one isocyanate-reactive

Have function and possess at least one hydrophilic group and / or a potentially hydrophilic group,

C) and at least one compound which has an isocyanate-reactive function and additional functional groups,

and subsequent mixing of the optionally neutralized resin with water.

Suitable as component A) are all resins which are listed in DE-OS 102004005 208.5 and DE-OS 10 2004 005 204.7. Preference is given to hydroxyl-containing ketone

Aldehyde resins, urea-aldehyde resins, phenol-aldehyde resins and their hydrogenated derivatives. The hydrophilic modification of B) is carried out by reacting a (poly) isocyanate and / or mixtures of different (poly) isocyanates with compounds having (in addition to the hydrophilic or potentially hydrophilic group) at least one isocyanate-reactive function, eg. For example, OH, NH, and having at least one hydrophilic group and / or a potentially hydrophilic group, ie, the hydrophilic after neutralization Examples of such compounds for hydrophilic modification of the polyisocyanates are aminocarboxylic acids, hydroxysulfonic acids, aminosulfonic acids and hydroxycarboxylic acids.

The hydrophilic modification can also be done with already neutralized compounds.

Hydroxycarboxylic acids such as dimethylolpropionic acid, dimethylolbutyric acid, bis (hydroxyphenyl) valeric acid and / or hydroxypivalic acid are particularly preferred because they are neutralized with volatile bases such. B. amines, strong hydrophilic effect, after evaporation of the volatile base, however, this effect decreases greatly, so that z. B. Coatings do not soften when exposed to moisture or start off white.

Dimethylolpropionic acid and 2 - [(2-aminoethyl) amino] -ethanesulfonic acid are also particularly preferred because they are capable of hydrophilically modifying (potentially) two hydrophobic polyisocyanates.

Suitable polyisocyanates for the preparation of B) are preferably di- to tetrafunctional polyisocyanates having a below 800 g / mol lying Poppy with aliphatic, (cyclo) aliphatic and / or cycloaliphatic bound isocyanate groups, such as are commonly used in the field of polyurethane coatings, as well as mixtures of these: 1-isocyanato-3,3,5-trimethyl-5-isocyanatomethylcyclohexane (isophorone diisocyanate; IPDI), trimethylhexamethylene diisocyanate (TMDI), 1,6-diisocyanatohexane (HDI), bis (4-isocyanatohexyl) -methane (Hi ₂ MDI), and Other polyisocyanates which are listed in DE-OS 24 56469, p. 5 and 6. Ebenfells suitable are oligomers obtainable from the monomeric polyisocyanates, whose recovery corresponds to the prior art and, for example, in the Journal of Practical Chemistry 336 (1994), 185-200 and Farb und Lack 100, 5 (1994), 330-335 and the literature cited therein. These are polyisocyanates with biuret, uretdione or isocyanurate structure, the latter obtainable by cyclotrimerization of the monomers. Also suitable are polyisocyanates as products of polyhydric alcohols and / or amines with monomeric isocyanates, such as. B. the product of trimethylolpropane and isophorone diisocyanate.

In addition, non-ionic hydrophilization may e.g. via polyethers, e.g. can be reacted with the above polyisocyanates and component A).

Particular preference is given to a hydrophilically modified polyisocyanate (B) of dimethylolpropionic acid and / or 2 - [(2-aminoethyl) amino] ethanesulfonic acid or derivatives thereof and IPDI and / or Hi ₂ MDI and / or HDI in a molar ratio of 1: 2.

The introduction of the functional components (C) can be carried out by reacting a (poly) isocyanate and / or mixtures of different (poly) isocyanates with compounds having at least one isocyanate-reactive function, for. B. OH, NH and with at least one further functional group in the way that at least one NCO function is maintained and subsequent reaction with A) before or after reaction with B). However, the preparation of the component C) can also be carried out in-situ during the pre-adduct preparation. As component C) it is possible in principle to use aliphatic or aromatic alcohols and / or amines or aromatic heteroaromatic ring systems which have a further functionality in addition to the NCO-reactive group. Preferred examples of such compounds are dimethylaminopropylatnine, diethanolamine, pyrrolidone and / or hydroxypivalic acid. The introduction of unsaturated groups, as described in DE-OS 103 38 560, DE-OS 103 38 562, DE-OS 10 2004 005 208.5, DE-OS 102004005 207.7, is not the subject of the present invention.

The reaction of A) with B) and / or C) can be carried out in bulk or preferably in the presence of a suitable auxiliary solvent. Preferred solids contents are 50 to 95% by mass, particularly preferably 60 to 80% by mass, when using an auxiliary solvent. Suitable Hüfslösemittel are either preferred those which have a boiling point below 100 ⁰ C at 1013 hPa and can be removed by distillation from the final aqueous system again completely to a residual content of 0, mass% and re-use, such as acetone, methyl ethyl ketone or tetrahydrofuran , or possibly higher boiling, which remain in the aqueous system, such as butyl glycol, butyl diglycol or N-methylpyrrolidone. The below 100 ° C boiling auxiliary solvents are therefore preferred because they allow the production of purely aqueous, solvent-free and therefore environmentally friendly dispersions. The use of the higher-boiling solvents - possibly also proportionally - or solvent mixtures having a boiling point above 100 ° C is technically possible, but not preferred and not sought. An advantage of the method according to the invention lies precisely in the fact that it is possible completely to dispense with organic solvents in the finished aqueous resin dispersion and still obtain solids-rich, stable dispersions.

In a preferred embodiment 1), as component C), e.g. an adduct of 1 mol of diisocyanate and 1 mol of a functional NCO-reactive component optionally prepared using a suitable solvent and a suitable catalyst.

As component B), e.g. an adduct of 2 moles of diisocyanate and 1 mole of dimethylolpropionic acid and / or 2 - [(2-aminoethyl) amino] ethanesulfonic acid or derivatives thereof are optionally prepared using a suitable solvent and a suitable catalyst.

The separately prepared products are added to a solution or melt of the hydroxyl-containing ketone, ketone-aldehyde, urea-aldehyde or their hydrogenated secondary products (A) and reacted.

It has proved to be advantageous to react 1 mol of component A, based on M _n , with from 0.1 to 10 mol, in particular from 0.25 to 5 mol, of component C).

It has proved to be advantageous, 1 mol of the reaction product of component A and C. - With respect to M _n - with 0.1 to 1.0 mol, preferably 0.3 to 0.75 mol to bring the component B to the reaction.

Depending on the reactivity of the components to each other, the temperature of the reaction is selected. There have in all reaction steps, temperatures from 30 to 245 ⁰ C, preferably between 50 and 140 ° C proved.

If necessary, it is possible first to neutralize with a suitable neutralizing agent and then to disperse the neutralized reaction product in water. Alternatively, it may be dispersed directly in a water / neutralizer mixture.

If desired, the solvent optionally present can be separated off after the reaction has ended, in which case a solution is usually obtained until the dispersion of the product according to the invention is obtained.

In a preferred embodiment 2) can be used as component B) z. For example, an adduct of 2 moles of diisocyanate and 1 mole of dimethylolpropionic acid and / or 2 - [(2-aminoethyl) amino] ethanesulfonic acid or derivatives thereof are optionally prepared using a suitable solvent and a suitable catalyst.

The product is added to a solution or melt of the hydroxyl-containing ketone, ketone-aldehyde, urea-aldehyde or their hydrogenated secondary products (A) and the component C) and further polyisocyanate and reacted.

It has proved to be advantageous to react 1 mol of the reaction product of components A and C with respect to M _n with 0.1 to 1.0 mol, preferably 0.3 to 0.75 mol, with component B. Depending on the reactivity of the components to each other, the temperature of the reaction is selected. Temperatures between 30 and 245 ^° C., preferably between 50 and 140 ^° C., have proven successful in all reaction steps.

Optionally, a suitable catalyst for the preparation of the resins of the invention can be used. Suitable are all known in the literature compounds that accelerate an NH or OH-NCO reaction, such as. B. diazabicyclooctane (DABCO) or dibutyltin dilaurate (DBTL), titanic acid esters, bismuth salts.

When the hydrophilicizing agent forms a potentially hydrophilic group, e.g. As a carboxyl group or a tertiary amino group introduced into the polyisocyanate, it can be converted by subsequent neutralization in an ionic hydrophilic group.

The neutralization of the resins according to the invention according to the anionically modified

Embodiments 1) and 2) can be carried out with inorganic and organic bases, such as.

As ammonia or organic amines. Preference is given to using primary, secondary and tertiary amines, such as. Ethylamine, propylamine, dimethylamine, dibutylamine,

Cyclohexylamine, benzylamine, morpholine, piperidine and triethanolamine. Particular preference is given to volatile tertiary amines, in particular dimethylethanolamine, diethylethanolamine, 2-

Dimethylamino-2-methyl-1-propanol, triethylamine, tripropylamine and tributylamine.

The amount of neutralization depends on the content of potentially neutralisable groups in the hydrophilically modified polyisocyanate and is preferably 50 to 130% of the

Amount of neutralization necessary for stoichiometric neutralization. In case of cationically hydrophilized systems are neutralized in the same way with suitable acids, such as acetic acid, formic acid, benzoic acid or lactic acid.

Before adding water, the reaction product of A, B and C may optionally be combined with other non-hydrophilic resins or other water-soluble or water-dilutable components and then dispersed together. This measure makes it technically advantageous to achieve a high solids content of the dispersions of more than 35% by mass, preferably from 35 to 40% by mass, to about 50% by mass.

The resin dispersions of the invention have good storage stabilities and are suitable as resins or additional resins in BescMchtungsstoffen, ballpoint pen inks and inks, polishes, glazes, fillers, cosmetics and / or sealing and insulating materials. Also for use in adhesives, such. As for the bonding of textiles, leather, paper and similar materials, such resin dispersions are suitable.

Due to the usually very high softening point, coatings result with fast drying and thorough drying and good blocking resistance. The resin dispersions of the invention are at least 6 weeks at 50 ⁰ C sedimentation stable.

example

The invention will be illustrated by the following examples.

Example 1) 1) Preparation of the hydrophilically modified Polvisocvanats B \ an adduct O and its reaction with A)

To a mixture of 60 g of dimethylolpropionic acid (DMPS), 217 g of acetone and 0.3 g of a

10 wt% solution of dibutyltin dilaurate (DBTL) in acetone is added with stirring 201 g of isophorone diisocyanate so quickly that the exothermic reaction remains well manageable. The mixture is then stirred at 60 ° C until the DMPS completely dissolved and the NCO number of the solution has fallen below 8.4% NCO (determined according to DIN 53185).

To 45.6 g IPDI 17.4 g of pyrrolidone are added in a nitrogen atmosphere and stirred at 80 ⁰ C to an NCO content of 13.6%.

After cooling to room temperature, the two precursors are combined in a nitrogen atmosphere, with 544 g of a hydroxyl-containing ketone / aldehyde resin (OHZ 310 mg KOH / g, resin SK, Degussa AG), which is dissolved in 508 g of acetone, and with 1.24 g of a 10% DBTL solution in acetone. It is stirred at reflux temperature until an NCO content of less than 0.15% is reached.

2) dispersing the modified resin V)

250 g of the solution prepared under 1) are neutralized at room temperature with stirring by the addition of 6.8 g of triethylamine and by adding 457 g of deionized

Water dispersed with vigorous stirring. The auxiliary solvent acetone and proportional water are removed in vacuo, and it becomes a storage-stable, finely divided, slightly opalescent

Resin dispersion having a solids content of about 24.8% by mass, a pH of 8.0 and a viscosity of about 90 mPas.

Example 2.)

1) Preparation of the hydrophilically modified Polvisocvanats B), an adduct C) and its reaction with A)

253 g of isophorone diisocyanate are added with stirring to a mixture of 51 g of dimethylolpropionic acid (DMPS), 253 g of acetone and 0.3 g of a 10% by mass solution of dibutyltin dilaurate (DBTL) in acetone so quickly that the exothermic reaction is readily controllable remains. The mixture is then stirred at 60 ⁰ C until the DMPS completely dissolved and the NCO number of the solution has fallen below 11.8% NCO (determined according to DIN 53185). After cooling to room temperature in nitrogen atmosphere, the precursor with 480 g of a hydroxyl-containing ketone / Aldehydhatzes (OHZ 310 mg KOH / g, resin SK, Degussa AG), which is dissolved in 400 g of acetone, and with 0.5 g of a 10% DBTL solution in acetone The mixture is stirred at reflux temperature until an NCO content of less than 1.3% is reached. Then 38.3 g of diethanolamine dissolved in 31.2 g of acetone are added, and it is stirred to an NCO content below 0.15%.

2) dispersing the modified resin 1)

250 g of the solution prepared under 1) are neutralized at room temperature with stirring by adding 6.3 g of triethylamine and dispersed by introducing 335 g of deionized water with vigorous stirring. The auxiliary solvent acetone and proportional water are removed in vacuo, and there is a storage-stable, finely divided, slightly opalescent resin dispersion having a solids content of about 29.5% by mass, a pH of 8.6 and a viscosity of about 520 mPas received.

Claims

claims:

1. Aqueous, functionalized resin dispersions obtainable by reaction or proportionate reaction of

A) hydroxyl-containing ketone, ketone / aldehyde, urea / aldehyde resins or their hydrogenated derivatives and

B) at least one modified isocyanate and / or polyisocyanate having at least one free NCO group, obtainable by reacting at least one isocyanate and / or polyisocyanate with compounds which have at least one isocyanate-reactive function in addition to the hydrophilic or potentially hydrophilic group and at least one hydrophilic Have a group and / or a potentially hydrophilic group,

C) and at least one compound which has an isocyanate-reactive function and has additional functional groups,

and then mixing the resin or the neutralized resin with water.

2. resin dispersions according to claim 1, characterized in that are used as component C) compounds having at least one isocyanate-reactive function and at least one further functional group.

3. resin dispersions according to claim 1, characterized in that as component C) alcohols and / or amines having in addition to the NCO-reactive group has a further functionality can be used.

4. Haizdispersionen according to claim 1, characterized in that are used as component C) Dimethylaπdnopropylamin, diethanolamine, pyrrolidone and / or hydroxypivalic.

5. Resin dispersions according to claim 1, characterized in that component C) is reacted with a (poly) isocyanate and / or mixtures of different (poly) isocyanates such that at least one NCO function is retained and subsequently with A) before, during or after reaction with B).

6. Resin dispersions according to one of the preceding claims, characterized in that component B) using tert. Aminoalcohols, aminocarboxylic acids,

Hydroxysulfonic acids, aminosulfonic acids or / and hydroxycarboxylic acids is produced.

7. Resin dispersions according to one of the preceding claims, characterized in that component B) is prepared using dimethylolpropionic acid and / or 2 - [(2-aminoethyl) amino] ethanesulfonic acid.

8. Resin dispersions according to one of the preceding claims, characterized in that for the preparation of B) di- to tetratunktionelle polyisocyanates are used with a below 800 g / mol lying poppy.

9. resin dispersions according to any one of the preceding claims, characterized in that for the preparation of B) polyisocyanates with aromatic, aliphatic and / or cycloaliphatic bound isocyanate groups or mixtures of these are used.

10. Resin dispersions according to one of the preceding claims, characterized in that l-isocyanato-3,3,5-trimethyl-5-isocyanatomethylcyclohexane (isophorone diisocyanate; IPDI), trimethylhexamethylene diisocyanate (TMDI), 1,6-diisocyanatohexane (HDI), bis (4 - Isocyanatohexyl) -methane (H _{] 2} MDI) can be used.

11. Resin dispersions according to one of the preceding claims, characterized in that are used for the preparation of B) polyisocyanates with biuret, uretdione or isocyanurate structure.

12. Resin dispersions according to one of the preceding claims, characterized in that for the preparation of B) polyisocyanates from the reaction of polyhydric alcohols and / or amines are used with monomeric isocyanates.

13. Resin dispersions according to one of the preceding claims, characterized in that for the preparation of B) dimethylolpropionic acid and isophorone diisocyanate (TPDI) in a molar ratio 1: 2 are used.

14. Resin dispersions according to one of the preceding claims, characterized in that the reaction of A) with B) and C) and the dispersion takes place in substance.

15. Resin dispersions according to one of the preceding claims, characterized in that the reaction of A) with B) and C) and the dispersion in the presence of a Auxiliary solvent takes place.

16. Resin dispersions according to one of the preceding claims, characterized in that the auxiliary solvent used has a boiling point below 100 ° C at 1013 hPa.

17. Resin dispersions according to one of the preceding claims, characterized in that the Hüfelösemittel used N-methylpyrrolidone, acetone or / and

Methyl ethyl ketone and / or tetrahydrofuran.

18. Resin dispersions according to one of the preceding claims, characterized in that the neutralization is carried out with inorganic or organic bases.

19. Resin dispersions according to one of the preceding claims, characterized in that are used for the neutralization of dimethylethanolamine and / or diethylethanolamine and / or 2-dimethylamino-2-methyl-l-propanol and / or triethylamine and / or ammonia.

20. Resin dispersions according to one of the preceding claims, characterized in that for neutralization 50 to 130% of the neutralization amount, which is necessary for a stoichiometric neutralization is used.

21. Resin dispersions according to one of the preceding claims, characterized in that before Wasserzugäbe one or more non-water-soluble or water-dilutable

Components are added.

22. A process for preparing aqueous, functionalized resin dispersions by reaction or proportionate reaction of

C) and at least one compound which have an isocyanate-reactive function and have additional functional groups,

and subsequent mixing of the optionally neutralized resin with water.