WO2009047148A1 - Block copolymers comprising a polyalkylene oxide unit and at least one terminal polyalkyleneimine unit - Google Patents

Abstract

Block copolymers which comprise a straight-chain or branched polyalkylene oxide block and at least one terminal polyalkyleneimine block, a process for preparation thereof, the use thereof as adhesion promoters and hardeners, and modified block copolymers of the type mentioned, in which the polyalkyleneimine blocks have additional functional groups.

Description

 Block copolymers comprising a polyalkylene oxide unit and at least one terminal polyalkyleneimine unit

description

The invention relates to block copolymers which comprise a central, straight-chain or branched polyalkylene oxide block and at least one terminally arranged polyalkyleneimine blocks, a process for their preparation, their use as adhesion promoters and hardeners and modified block copolymers of the type mentioned, in which the polyalkyleneimine blocks have additional functional groups ,

It is known to alkoxylate polyethyleneimine with alkylene oxides. Here, block copolymers are obtained in which a central polyethyleneimine molecule is substituted with a plurality of terminal polyalkylene oxide side chains.

EP-A 0 541 018, EP-A 0 784 645 and WO 98/12235 disclose polyethylenimines which have been alkoxylated with ethylene oxide and / or propylene oxide and use for splitting emulsions. EP-A 221 774 and EP-A 222 557 disclose alkoxylated polyethyleneimines and their use for detergent and cleaner formulations.

It is furthermore known from DE 34 04 538 to react polyethyleneimine with bifunctional alkylating agents such as, for example, β, β-dichlorodiethyl ether, giving partially crosslinked polyethyleneimine.

Copolymers with an inverse structure to the described products, i. A single polyalkylene oxide block, which is connected to one or more terminal, unencealed Polyethyleniminblöcken, are not yet known.

The object of the invention was to provide novel block copolymers available.

Accordingly, block copolymers have been found which have exactly one, straight-chain or branched polyalkylene oxide block and at least one terminally arranged polyalkyleneimine block, the block copolymers having the general formula (I)

and the radicals R ¹ , R ² , X and n and m have the following meaning: n: a natural number of at least 1,

R ¹ : an n-valent hydrocarbon radical having n to 20 n carbon atoms,

R ² : independently of one another, an alkylene radical having 2 to 4 carbon atoms, m (n): a number of at least 1, where the sum m over all numbers m (n) of a block copolymer gives at least 2,

X: a polyalkyleneimine radical of the general formula (II)

where R ³ , R ⁴ , R ^{5 have} the following meaning:

R ³ : independently of one another 1, 2-alkylene radicals of the general formula -CH 2 -CH (R ⁶ ) -, where R ^{6 is} hydrogen or a C 1 - to C 4 -alkyl radical, R ⁴ : independently of one another a radical of the formula (III)

or a radical R ⁷ , where R ^{7 is} hydrogen or a C 1 to C 10 -alkyl radical,

R ⁵ : independently of one another are hydrogen or a radical of the formula (III),

where the indices x and y each have at least the value of 1, and the total number z of all alkyleneimine units of the formulas (II) and (III) present in the block copolymer is 2 n to 30,000.

In addition, a process for the preparation of such block copolymers by reacting polyetheramines with alkyleneimines and the use of such block copolymers as adhesion promoters, for coating surfaces, as curing aids or curing agents in epoxy resins have been found.

In a further embodiment of the invention, modified block copolymers have been found in which the terminal polyalkyleneimine blocks have additional functional groups. More specifically, the following is to be accomplished for the invention:

The block copolymers according to the invention comprise a central, straight-chain or branched polyalkylene oxide block and at least one terminally arranged polyalkyleneimine blocks. The structure can be represented in a general form with AX _n , where A represents the polyalkylene oxide block, X the polyalkyleneimine blocks and n their number. They may, for example, be linear block copolymers of the general formula AX or XAX, or branched block copolymers of the general formula AX3, AX ₄ or AX5. Depending on the nature of the block A, the block copolymers may, for example, have a star-shaped structure, an elongated shape or a comb-like structure.

The block copolymers according to the invention have the general formula (I)

on. Here, an n-valent hydrocarbon radical R ^{1 is} connected to n radicals of the general formula - (OR ² -) _m (n) -X, where n is a natural number of at least 1, in particular from 2 to 10, preferably from 2 to 6, more preferably 2 to 5 and most preferably 2 or 3 stands.

The n-valent hydrocarbon radical here has n to 20 n, preferably n to 10 n and particularly preferably n to 5 n carbon atoms. It may be a linear, branched or cyclic aliphatic and / or aromatic hydrocarbon radical, wherein a noncyclic radical must be naturally branched at n> 2.

Examples of monovalent radicals include alkyl radicals such as methyl, ethyl, propyl, butyl radicals or phenyl radicals as well as the saturated and mono- or polyunsaturated radicals of fatty alcohols. Examples of divalent radicals R ¹ include alkylene radicals such as

1,2-Ethylene, 1,2-propylene, 1,3-propylene, 1,2-butylene, 1,4-butylene, 1,6-hexylene or 1,8-octylene radicals, aromatic radicals such as 1, 2-, 1, 3 or 1, 4-phenylene or bisphenol A derived radicals - (CeI-U) -C (CHsMCeI-U) -. In a divalent radical R ¹ , in a preferred embodiment of the invention, the alkylene radical R ² and the radical R ^{1 may be} identical.

Examples of trivalent radicals include in particular radicals alkanetriyl radicals, for example those of the formulas (a) or (b).

wherein R ^{14 is} an alkyl group, preferably an ethyl group.

Examples of tetravalent radicals include in particular alkanetetryl radicals, for example those of the formulas (c) or (d).

The radicals R ¹ are connected to a total of m alkoxy units -OR ² -, with the proviso that no more than one alkoxy unit is connected to one carbon atom of the radical R ¹ . The radicals R ² are each independently alkylene radicals having 2 to 4 carbon atoms. Examples of such radicals include 1,2-ethylene, 1,2-propylene, 1,3-propylene, 1,2-butylene or 1,4-butylene radicals. Preferably, these are 1,2-ethylene and / or 1,2-propylene radicals, particularly preferably 1,2-propylene radicals, ie radicals of the general formula -CH 2 -CH (CH 3) -

The number m (n) indicates in each case the average number of alkylene oxide units per group (OR ² -) m (n) -X, where m (n) is at least 1 in each case and where the sum m is over all numbers m ( n) of a block copolymer, ie the total number of all alkylene oxide units (OR ² -) - of a block copolymer of the formula (I), at least 2. The numbers m (n) and m are, in a known manner, average values for the respective degree of alkoxylation.

The terminal group X is a polyalkyleneimine radical of the general formula (II)

Here, the radicals R ^{3 are} each independently 1, 2-alkylene radicals of the general formula -CH 2 -CH (R ⁶ ) -, wherein R ^{6 is} hydrogen or a C 1 -C ₄ -alkyl radical. R ⁶ is preferably hydrogen or methyl and particularly preferably hydrogen, ie R ³ is preferably a 1, 2-ethylene group. The radical R ⁴ here in each case represents a radical of the formula

or a radical R ⁷ , where R ^{7 is} hydrogen or a C 1 to C 10 alkyl radical. Preferably, R ^{7 is} hydrogen, ie preferably R ^{4 is} hydrogen or a radical of the formula

The radicals R ⁵ in the formulas (II) and (III) are each independently hydrogen or a radical of the formula (III). The radical X may therefore have branches and the radicals (III) may themselves be branched. As a rule, X is a branched radical, where it is generally at least 20% of all nitrogen atoms in the radical X that are tertiary nitrogen atoms, in other words, branching-containing nitrogen atoms.

The indices x and y in the formulas each have at least the value of 1. The total number z of all alkyleneimine units of the formulas (II) and (III) present in the block copolymer is 2 n to 30,000, preferably 3 n to 10,000, preferably 4 n to 5,000, particularly preferably 5 n to 1,000.

In the case of the block copolymers according to the invention, the total number m of the alkylene oxide units and the total number of alkyleneimine units z are preferably selected such that the ratio z / m> 1, ie the number of alkyleneimine units in the block copolymer is equal to or greater than the number of alkylene oxide units ( OR ² -) in the block copolymer.

In a first preferred embodiment of the invention, the block copolymers (I) are block copolymers of the general formula (Ia)

where R ^{1 is} a C ¹ to C 10 alkoxy radical, preferably a methyl or ethyl radical, and R ^{2 is} a 1, 2-propylene radical. The total number m (1) of the alkoxy units in this preferred embodiment is 2.5 to 80, preferably 2.5 to 40 and particularly preferably 2.5 to 10. The radicals X are composed of Ethylenimineinheiten, ie R ³ is 1,2-ethylene. The average number of ethylenimine units in the group X (in this case, identical to the total number z) is 5 to 50.

In a second preferred embodiment of the invention, the block copolymers (I) are block copolymers of the general formula (Ib)

wherein R ¹ and R ^{2 are} each 1, 2-propylene radicals. The total number m of the alkoxy units (ie the sum of m (1) and m (2)) in this preferred embodiment is 2.5 to 80, preferably 2.5 to 40 and particularly preferably 2.5 to 10. The radicals X are composed of Ethylenimineinheiten, ie R ³ is 1, 2-ethylene. The average number of ethylenimine units per group X (ie the sum of x and y)) is 5 to 50, and correspondingly in the block copolymer of the formula (Ib) the total number z of all ethyleneimine units is 10 to 100.

In a third preferred embodiment of the invention, the block copolymers (I) are block copolymers of the formula (Ic) or (Id).

The total number m of the alkoxy units (ie the sum of m (1), m (2) and m (3)) in this third preferred embodiment is 2.5 to 100, preferably 5 to 100. The radicals X are composed of ethyleneimine units, ie R ³ is 1,2-ethylene. The the average number of ethylenimine units per group X (ie, the sum of x and y)) is 5 to 50, and accordingly, in the block copolymer of the formulas (Ic) or (Id), a total of 15 to 150 ethyleneimine units are present.

The block copolymers according to the invention are starting from polyetheramines of the general formula (IV)

be prepared, wherein the radicals R ¹ , R ² , R ⁷ , m and n have the meaning defined above. Such polyetheramines can be prepared in a known manner by reacting mono-, di- or polyalcohols of the general formula R ¹ (OH) _n initially with alkylene oxides R ² O to give alkoxylated alcohols of the general formula (IVa)

implements. The terminal OH groups can then be converted by means of a reductive amination into amino groups. The preparation of polyetheramines of the formula (IV) is known in principle to the person skilled in the art, and such polyetheramines are also commercially available (for example from Huntsman, BASF.). In the above formula (IV), R ^{7 is} preferably hydrogen, ie the polyethermines have primary amino groups. However, it is also possible to use polyetheramines which have alkyl groups as R ⁷ .

In a second synthesis step, the polyetheramines (IV) are used with at least 2 n units of alkyleneimine, preferably ethyleneimine and / or propyleneimine, particularly preferably ethylenimine. As a result, the terminal amino groups are converted into polyalkyleneimino groups X. The polymerization of alkyleneimines, in particular ethyleneimine to polyalkyleneimines, is known in principle to a person skilled in the art. It is carried out under acid catalysis. For this one can provide for example the Polyethe- Ramin dissolved in water, addition of the acid, heat up to temperatures> 80 ⁰ C and then added dropwise the desired amount of an aqueous solution of the alkylene lenimins. In this case, the dropping speed should be so slow that added alkyleneimine can each react as completely as possible with the already existing amine functions in order to suppress the formation of polyethyleneimine as by-product as far as possible. For example, the endpoint of the response can be be determined by a Preußmann test. The resulting solution of the polymer can be used directly as such. It is of course possible to isolate the polymer therefrom as a solid or to purify the solution, for example by ultrafiltration.

The block copolymers according to the invention can be used, for example, as adhesion promoters, for coating surfaces, as wetting assistants or as curing agents for epoxy resins. In addition, block copolymers, which also substantially comprise polypropylene oxide or polybutylene oxide units, are amphiphilic molecules.

The polyalkyleneimine blocks of the block copolymers of the invention may be further modified by reacting the unmodified block copolymers with at least one functionalizing reagent which is capable of reacting with amino groups. This results in modified block copolymers, each having the same backbone as the block copolymers used as starting material, but in which the polyalkyleneimine block is modified with additional groups. The modified block copolymers thus have exactly one straight-chain or branched polyalkylene oxide block and at least one terminally arranged modified polyalkyleneimine block. By such a modification, the properties of the polyalkyleneimine blocks can be changed and thus adapted to the requirements of certain applications.

Suitable functionalizing reagents are in principle all those which can also be used for the modification of polyalkyleneimines, in particular polyethyleneimine.

The unmodified block copolymers can be reacted, for example, with conventional quaternization reagents. This results in modified block copolymers whose polyalkylene blocks have quaternary N atoms, ie have ionic character. Examples of quaternizing reagents include alkyl halides or arylalkyl halides such as methyl halides or benzyl halides, as well as other, especially strong methylating, reagents such as dimethyl sulfate.

Preference is given to modified block copolymers of the general formula (V)

die Reste R¹, R², m und n die oben definierte Bedeutung haben und X² für einen modifizierten Polyalkyleniminrest steht. Die modifizierten Reste X² können durch nachträgliche Funktionalisierung der Reste X eines Blockcopolymers (I) erhalten werden.

the radicals R ¹ , R ² , m and n have the meaning defined above and X ^{2 is} a modified polyalkyleneimine radical. The modified radicals X ² can be obtained by subsequent functionalization of the radicals X of a block copolymer (I).

The modified radicals X ² have the general formula (VI),

wherein R ^{3 has} the meaning defined above.

The radicals R ⁸ independently of one another represent hydrogen, C 1 - to C 1 -alkyl-, a group R ¹⁰ or a radical of the formula (VII)

and the radicals R ⁹ independently of one another hydrogen, a group R ¹⁰ or a radical of the formula (VII). In the formulas (VI) and (VII), x, y and the quantities z and z / m derived therefrom have the meaning defined above.

The modified groups X ² differ from the unmodified groups X in that, in the radical X, hydrogen atoms of the primary and secondary amino groups are replaced by radicals R ¹⁰ or by C 1 to C ¹⁰ alkyl groups.

According to the invention, at least one of the groups R ⁸ and / or R ⁹ occurring in a modified block copolymer (V) is a group R ¹⁰ . In general, the ratio of the number of substituents R ¹⁰ with respect to the total number of all substituents present R ⁸ and R ⁹ 1 to 99%, preferably 10 to 90% and particularly preferably 20 to 80%.

R ¹⁰ hereby stands for a group selected from a group of the general formula - (CH 2) -I-R ¹¹ , a group of the general formula -C (O) NH-R ¹⁴ or a group of a group of the general formula -C (O ) -R ¹⁴ . In the above formula, I is 1 or 2 and R ^{11 is} a functional group selected from the group consisting of -COOH, -PO 3 H 2, -SO 3 H, -OH or groups comprising at least one ether unit. The functional group R ¹¹ is thus bound via one or two methylene groups as spacers to the nitrogen atom. It may of course also be salts of the acid groups mentioned.

R ¹⁴ is an aliphatic and / or aromatic, preferably an aliphatic hydrocarbon radical having 1 to 10 C atoms.

In a particularly preferred embodiment of the invention, the functional groups R ¹⁰ are functional groups selected from the group VOn-CH ₂ COOH, -CH ₂ -CH ₂ -COOH, -CH ₂ -CH ₂ -PO ₃ H ₂ , -CH ₂ -CH ₂ -PO ₃ H ₂ or salts thereof or alkoxy groups of the general formula - (CH ₂ CH (R ¹² ) -O-) _Z -R ¹³ , where R ¹² independently of one another are hydrogen, C 1 to C ₄ alkyl or phenyl; R ¹³ is a hydrogen or a straight-chain or branched, aliphatic and / or aromatic hydrocarbon radical having 1 to 20 carbon atoms and z is a number from 1 to 500, preferably 2 to 250 and particularly preferably 5 to 150 acts.

The preferred modified block copolymers (V) are prepared in analogy to methods known in the field of polyethyleneimine chemistry. Alkoxy-modified block copolymers can be prepared, for example, by introducing the unmodified block copolymers and reacting with alkylene oxides. Corresponding procedures are disclosed, for example, by DE 22 27 546 or EP 784 645. Groups of the formulas -CH ₂ -CH ₂ -COOH, -CH ₂ -CH ₂ -PO ₃ H ₂ or -CH ₂ -CH ₂ -SO ₃ H can be introduced by reaction of the block copolymer with acrylic acid, vinylphosphonic acid or vinylsulfonic acid. For example, groups of the formula -CH ₂ -COOH can be obtained by reaction with chloroacetic acid, and groups -CH ₂ -PO ₃ H ₂ can be obtained by reacting with formaldehyde or derivatives thereof and phosphorous acid under acid catalysis. Details of this are, for example, in

WO 98/14621, page 10, line 42 to page 11, line 19, d- to Cio-alkyl groups can be obtained in a manner known in principle by reaction with alkyl halides.

Groups of the general formula -C (O) NH-R ¹⁴ can be prepared by reaction with isocyanates OCN-R ¹⁴ and groups of the general formula -C (O) -R ¹⁴ by reaction with corresponding carboxylic acids R ¹⁴ -COOH, or reactive Derivatives thereof, such as carboxylic acid or carboxylic acid halides obtained.

By modifying with groups R ¹⁰ , the properties of the radicals X ^{2 can be changed} in comparison to unmodified radicals. By a simple alkylation is For example, the radical X ^{2 is more} hydrophobic than X, while the introduction of acid groups reduces the basicity of the rest.

The modified block copolymers can also be used, for example, as adhesion promoters. Alkoxylated products are particularly suitable as emulsion breakers, for example for splitting crude oil-water emulsions.

The following examples are intended to explain the invention in more detail.

A) Preparation of the block copolymers of the invention

Used polyetheramines:

In the following synthesis instructions, all percentages are by weight. The complete ethyleneimine conversion was determined by Preußmann test (R. Preußmann, Arzneimittel-Forschung 1969, 19, 1059-1073.). The determination of the amine number was carried out by potentiometric titration according to DIN 53176.

Example 1 :

In a 1 L four-necked flask with dropping funnel, intensive stirrer and reflux condenser, 64.1 g of polyetheramine A1 are introduced, diluted with 50 g of deionized water and cooled to 0 ⁰ C. Then carefully add dropwise 54.8 g of sulfuric acid (25%). The original is heated to 95 ⁰ C. From an internal temperature of 60 ⁰ C are added dropwise within 1 h gradually 400 g Ethyleniminlösung (60% ethylenimine in water). The reaction is highly exothermic. The reaction is completed after a negative Preußmann test. The properties of the products obtained are summarized in Table 1. Example 2:

In a 1 L four-necked flask with dropping funnel, intensive stirrer and reflux condenser, 64.2 g of polyetheramine A1 are introduced, diluted with 50 g of deionized water and cooled to 0 ⁰ C. Then carefully add dropwise 54.8 g of sulfuric acid (25%). The original is heated to 95 ⁰ C. From an internal temperature of 60 ⁰ C are added dropwise within 1 h gradually 200 g Ethyleniminlösung (60% ethylenimine in water). The reaction is highly exothermic. The reaction is completed after a negative Preussmann test.

The properties of the products obtained are summarized in Table 1.

Example 3:

In a 1 L four-necked flask with dropping funnel, intensive stirrer and reflux condenser, 32.1 g of polyetheramine A1 are introduced, diluted with 25 g of deionized water and cooled to 0 ⁰ C. Then added dropwise cautiously 27.4 g of sulfuric acid (25%). The original is heated to 95 ⁰ C. From an internal temperature of 60 ⁰ C (60% ethyleneimine in water) are added dropwise within 1 h conces- gradually 400 g ethyleneimine. The reaction is highly exothermic. The reaction is completed after a negative Preußmann test. The properties of the products obtained are summarized in Table 1.

Example 4:

In a 1 L four-necked flask with dropping funnel, intensive stirrer and reflux condenser, 8 g polyetheramine A2 are introduced 81, diluted with 50 g of deionized water and cooled to 0 ⁰ C. Then carefully add dropwise 54.8 g of sulfuric acid (25%). The original is heated to 95 ⁰ C. From an internal temperature of 60 ⁰ C are added dropwise within 1 h gradually 400 g Ethyleniminlösung (60% ethylenimine in water). The reaction is highly exothermic. The reaction is completed after a negative Preußmann test. The properties of the products obtained are summarized in Table 1.

Example 5:

In a 1 L four-necked flask with dropping funnel, intensive stirrer and reflux condenser, 53.4 g of polyetheramine A2 are introduced, diluted with 40 g of deionized water and cooled to 0 ⁰ C. Then carefully added dropwise 35.8 g of sulfuric acid (25%). The original is heated to 95 ⁰ C. From an internal temperature of 60 ⁰ C (60% ethyleneimine in water) conces- within 1 h and after 400 g ethyleneimine drips. The reaction is highly exothermic. The reaction is completed after a negative Preußmann test. The properties of the products obtained are summarized in Table 1.

Table 1: Properties of the resulting block copolymers

B) Application tests

B1) Treatment of metal surfaces

Polyethyleneimine is used i.a. used as a bonding agent. For this purpose, it must be coatable on surfaces, in particular metal surfaces, in the thinnest possible layer (typically 0.5 to 1 μm).

General working instructions

Test panels made of structural steel St 1.0037 were used for the tests. The steel sheets were in an alkaline cleaning solution (Ridoline ^® C72, Fa. Henkel) immersed for 10-20 seconds, immediately rinsed with deionized water and then dried with nitrogen.

In each case, a 5% aqueous solution of the respective block copolymer or the samples used for comparison purposes was used. The aqueous solutions were each homogenized and filled into an immersion bath.

The test panels were immersed once in the immersion bath for 10 seconds, then dried at room temperature for 60 minutes and at 120 ^° C. for 60 minutes. The layer thickness was in each case about 0.5-1 μm. The coated test panels showed no changes in color and metallic gloss in comparison with the untreated test panel. The quality of the coating was further assessed according to two criteria.

To assess the completeness of the coating, the area coverage of the film was visually estimated (% area covered with respect to the total surface area of the metal).

Furthermore, the edge distance was determined. This size refers to the fact that the coating applied to a surface of a workpiece often does not extend to the edge of the workpiece, but a more or less large distance between the edge and the coating film remains. This distance is called the edge distance. That part of the workpiece remains uncovered is, for obvious reasons, highly undesirable. The effect is all the more significant, the smaller the amount applied or the layer thickness of the film used. To determine the edge distance, the distance of the polymer film on the sheet from the sheet edge was determined on a total of 20 measuring points, each 2 cm apart, and from this the mean value was calculated.

Commercially available polyethyleneimine at 800 g / mol and 25,000 g / mol and polypropylene glycol at 300 g / mol were used for comparison purposes.

The results of the coating experiments are summarized in Table 1.

Table 1: Test results, net behavior on steel sheets

The block copolymers of the present invention are good on steel surfaces and, in spite of the polypropylene glycol blocks, behave much like pure polyethyleneimines. With a pure polypropylene glycol, however, a very large edge distance and a significantly lower surface coverage was achieved. B2) Use as wetting aid

Wetting agents are substances that reduce the interfacial tension of water or other liquids to such an extent that these liquids can penetrate into porous bodies and wet them and displace them with displacement of the air. As wetting aids usually surfactants are used.

In the following experiments, the use of the block copolymers according to the invention as a wetting assistant for cement was investigated. When mixing cement, the fastest possible wetting of the cement with water is desired.

At the same time, it is undesirable that added wetting aids cause the cement paste to foam.

General test procedure:

In a test tube (diameter 1 cm) 44 g of cement (Portland cement PZ 35F) was filled (results in a filling height of 14 cm) and covered with 10 ml of a 0.1% solution of the substances to be tested in water. The time to complete uptake of the 10 ml in the cement layer was determined in each case. With a ruler, the penetration depth of the solution into the cement layer was measured as a function of time.

For comparison, demineralized water was used without the addition of auxiliaries and three different solutions of commercially available surfactants.

The results are summarized in Tables 2 and 3.

Table 2: Time to complete uptake of the 10 ml in the cement layer σ)

Table 3: Cement wetting test Surfactant 1: fatty alcohol alkoxylate Surfactant 2: ethoxylated C 13 oxo alcohol (8 ethoxy units)

B3) Determination of the foaming power

The determination of the foaming power was carried out according to the perforated disc impact method (DIN EN 12728).

The measure of foamability is the volume of foam produced under the conditions of this test specification.

Equipment: Measuring cylinder (1000 ml)

Perforated Discs - Foam Stamp (Perforated Disc Diameter: approx. 5.5 cm)

Execution:

A solution of 10 g / l of the substance to be tested in demineralized water is prepared and 200 ml of it filled into the measuring cylinder. The foam is produced by striking the foam stamp 30 times (each time). The foam volume is measured immediately after the end of the experiment and another 30 seconds after completion of the slide.

Evaluation:

1.) ml foam = [total volume (foam + solution)] - 200 ml (sample solution) 2.) foam volume based on the foam volume of a comparative solution:

V ₂ / Vr 100 = Vs

Vs = foam volume in%, based on the foam volume of the reference solution Vi = foam volume of the reference solution in ml V2 = foam volume of the sample solution in ml

For comparison purposes, 3 commercial surfactants were used, as well as a mixture of a block copolymer of the invention and a surfactant used.

The test results are summarized in Table 4.

Table 4: Test results foaming behavior

Evaluation of the test series B2 and B3:

All polymers and surfactant surfactants are significantly faster in the initial time of <30 seconds than water alone. The polymers show better penetration over the entire time corridor. The 10 ml solution is taken up faster in the polymers according to Examples 1, 2, 4 and 5.

The foaming experiments show that the block copolymers of the invention do not foam, in contrast to surfactants. Unwanted foaming of cement mixtures is thus avoided. But they are not foam suppressants, as can be seen in the mixture of surfactant and block copolymer.

Claims

claims Block copolymers comprising polyalkyleneimine and polyalkylene oxide units, characterized in that they are exactly one straight-chain or branched polyalkylene oxide block and at least one terminally arranged polyalkyleneimine block, the block copolymers having the general formula (I)

and the radicals R ¹ , R ² , X and n and m have the following meaning: n: a natural number of at least 1, R ¹ : an n-valent hydrocarbon radical having n to 20 n carbon atoms, R ² : independently of one another an alkylene radical having 2 to 4 carbon atoms, m (n): a number of at least 1, where the sum m over all numbers m (n) of a block copolymer gives at least 2, X: a polyalkylenimine radical of the general formula (II )

where R ³ , R ⁴ , R ^{5 have} the following meaning: R ³ : independently 1, 2-alkylene radicals of the general formula -CH ₂ -CH (R ⁶ ) -, where R ^{6 is} hydrogen or a C 1 to C ₄ alkyl radical, R ⁴ : independently of one another a radical of the formula

or a radical R ⁷ , where R ^{7 is} hydrogen or a C 1 to C 10 -alkyl radical, R ⁵ : independently of one another are hydrogen or a radical of the formula (III), where the indices x and y each have at least the value of 1, and the total number z of all alkyleneimine units of the formulas (II) and (III) present in the block copolymer is 2 n to 30,000. 2. Block copolymers according to claim 1, with the proviso that the ratio z / m> 1. 3. Block copolymers according to claim 1 or 2, characterized in that R ³ is a 1, 2-ethylene radical -CH 2 -CH 2 - acts. 4. Block copolymers according to one of claims 1 to 3, characterized in that n is 2 to 6. 5. Block copolymers according to one of claims 1 to 4, characterized in that R ^{4 is} H or a radical of formula (III). 6. Block copolymer according to one of claims 1 to 5, characterized in that R ³ is a 1, 2-propylene radical -CH 2 -CH (CH 3) - is. 7. Block copolymers according to one of claims 1 to 6, characterized in that the sum of x and y is 5 to 100. 8. A process for the preparation of block copolymers according to one of claims 1 to 7, which comprises reacting a polyetheramine of the general formula (IV)

with at least 2n units of alkyleneimine, wherein the R ¹ , R ² , R ⁷ , m (n) and n each have the meaning defined above. 9. Use of block copolymers according to any one of claims 1 to 7 as a primer. 10. Use of block copolymers according to any one of claims 1 to 7 for coating surfaces. 1 1. Use of block copolymers according to any one of claims 1 to 7 as a curing agent in epoxy resins. 12. Use of block copolymers according to any one of claims 1 to 7 as wetting aids. 13. Modified block copolymers comprising modified polyalkyleneimine and polyalkylene oxide units, characterized in that it is exactly one straight-chain or branched polyalkylene oxide block and at least one terminally arranged modified polyalkyleneimine block obtainable by reacting unmodified block copolymers according to one of claims 1 to 7 with at least one functionalizing reagent , which is capable of reacting with amino groups. 14. Modified block copolymers according to claim 13, characterized in that the functionalizing reagent is a quaternizing reagent, and the polyalkyleneimine units are completely or partially quaternized. 15. Block copolymers according to claim 13, characterized in that the block copolymers have the general formula (V)

exhibit, where R ¹ , R ² , m (n) and n have the meaning defined above, and an X ² is a modified polyalkylenimine radical of the general formula (VI)

where R ^{3 has} the meaning defined above and R ⁸ and R ^{9 have} the following meanings: R ⁸ : independently of one another hydrogen, C 1 - to C 1 -alkyl-, a group R ¹⁰ or a radical of the formula (VII)

R ⁹ : independently of one another hydrogen, a group R ¹⁰ or a radical of the formula (VII), R ¹⁰ : a group selected from the group of • a group of the general formula - (CH 2) -I-R ¹¹ , where I is 1 or 2 and R ^{11 is} a functional group selected from the group of -COOH, -PO 3 H 2, -SO 3 H or in each case their salts, OH or at least one ether unit comprising groups, A group of the general formula -C (O) NH-R ¹⁴ , where R ¹⁴ is an aliphatic and / or aromatic hydrocarbon radical having 1 to 10 C atoms, or A group of the general formula -C (O) -R ¹⁴ , where x and y are as defined above, with the proviso that at least one of the groups R ⁸ and / or R ⁹ occurring in a modified block copolymer (V) is a group R ¹⁰ . 16. Modified block copolymers according to claim 15, characterized in that the functional groups R ¹⁰ are functional groups selected from the group of -CH ₂ -COOH, -CH ₂ -CH ₂ -COOH, -CH ₂ -CH ₂ -PO ₃ H ₂ , - CH ₂ -CH ₂ -POsH ₂ -bzw. Salts thereof - or alkoxy groups of the general formula - (CH ₂ CH (R ¹² ) -O-) _Z -R ¹³ , wherein R ^{12 is} independently hydrogen, C 1 to C ₄ alkyl or phenyl and in R ¹³ is a hydrogen or a straight-chain or branched, aliphatic and / or aromatic hydrocarbon radical having 1 to 20 carbon atoms. 17. Modified block copolymers according to claim 15 or 16, characterized in that the ratio of the number of substituents R ¹⁰ with respect to the total number of all substituents present R ⁸ and R ^{9 is} 10 to 90%.