WO2010040612A1 - Phosphated polycondensation product, method for production and use thereof - Google Patents

Abstract

The invention relates to a phosphate polycondensation product which can be used as flow promoter for hydraulic binders and which contains a structural element (I) having an aromatic or heteroaromatic and one polyether side-chain, a phosphate structural element (II) having an aromatic or heteroaromatic and a structural element (III) having an aromatic or heteroaromatic, wherein structural element (II) and structural element (III) differ exclusively in that the OP(OH)2-group of structural element (II) is replaced by H in structural element (III) and structural element (III) is not the same as structural element (I).

Description

 Phosphated polycondensation product, process for its preparation and use

description

The present invention relates to a phosphated polycondensation product, a process for its preparation and the use as additives in a building material mixture.

It is known that aqueous slurries of powdered inorganic or organic substances, such as clays, silicate, chalk, carbon black, rock powder and hydraulic binders to improve their processability, d. H. Kneadability, spreadability, sprayability, pumpability or flowability, additives added in the form of dispersants. Such additives are able to prevent the formation of solid agglomerates, to disperse the particles already present and re-formed by hydration and thus to improve the processability. This effect is also exploited specifically in the production of building material mixtures containing hydraulic binders such as cement, lime, gypsum, hemihydrate or anhydrite.

In order to convert these building material mixtures on the basis of said binder into a ready-to-use, processable form, substantially more mixing water is generally required than would be necessary for the subsequent hydration or hardening process. The void fraction in the concrete body formed by the excess, later evaporating water leads to significantly worsened mechanical strength and resistance.

In order to reduce this excess amount of water at a given processing consistency and / or to improve processability at a given water / binder ratio, additives are used which are generally referred to as water reducers or flow agents. As such agents in particular polycondensation products and copolymers are used in practice.

In WO 2006/042709, polycondensation products based on an aromatic or heteroaromatic compound (A) having 5 to 10 C atoms or heteroatoms with at least one oxyethylene or oxypropylene radical and an aldehyde (C) are selected from the group formaldehyde Glyoxylic acid and benzaldehyde or mixtures thereof, which, compared to the conventionally used Poykondensationsprodukten cause improved liquefying action of inorganic binder suspensions and this effect over a longer In a particular embodiment, these may also be phosphated polycondensation products, but the phosphated monomers used are relatively expensive since they must be prepared and purified separately.

It is an object of the present invention to provide an economical dispersant, based on a phosphated polycondensation product, for hydraulic binders, which is particularly well suited as a superplasticizer / water reducer for concrete, and can be produced in a simple manner and at low cost.

The solution to this problem is a polycondensation product containing

(I) at least one structural unit having an aromatic or heteroaromatic and a polyether side chain, and

(II) at least one phosphated an aromatic or heteroaromatic containing structural unit and

at least one structural unit having an aromatic or heteroaromatic compound,

wherein structural unit (II) and structural unit (III) differ solely in that the OP (OH) 2 group of the structural unit (II) in structural unit (III) is replaced by H and structural unit (III) is not structural unit (I).

The structural units (I), (II) and (III) can be described in more detail by the following general formulas

(I)

mit

With

A is the same or different and is represented by a substituted or unsubstituted aromatic or heteroaromatic compound having 5 to 10 C atoms

With B is the same or different and represented by N, NH or O.

with n = 2 if B = N and n = 1 if B = NH or O

With

R ¹ and R ^{2 are} independently the same or different and represented by a branched or unbranched d- to Cio-alkyl radical, Cs to Cs-cycloalkyl radical, aryl radical, heteroaryl radical or H.

with a the same or different and represented by an integer from 1 to 300

where X is identical or different and represented by a branched or unbranched C 1 to C 10 -alkyl radical, C 8 to C 8 -cycloalkyl radical, aryl radical, heteroaryl radical or H

(Hl)

für (II) und (III) jeweils:

for (II) and (III) respectively:

With

D is identical or different and represented by a substituted or unsubstituted aromatic or heteroaromatic compound having 5 to 10 C atoms

With E is the same or different and represented by N, NH or O.

with m = 2 if E = N and m = 1 if E = NH or O

With

R ³ and R ⁴ are each independently the same or different and represented by a branched or unbranched C 1 to C 10 alkyl radical, C 8 to C 8 cycloalkyl radical, aryl radical, heteroaryl radical or H.

with b being the same or different and represented by an integer from 0 to 300

In a preferred embodiment, the polycondensation product contains a further structural unit (IV), which is represented by the following formula

mit

With

Y independently of one another, identical or different, and represented by (I), (II), or further constituents of the polycondensation product

With

R ^{5 is} identical or different and represented by H, CH 3, COOH or a substituted or unsubstituted aromatic or heteroaromatic compound having 5 to 10 C atoms

With

R ^{6 is} identical or different and represented by H, CH 3, COOH or a substituted or unsubstituted aromatic or heteroaromatic compound having 5 to 10 C atoms.

Here, R ⁵ and R ⁶ in structural unit (IV) independently of one another are preferably represented by H, COOH and / or methyl.

The molar ratio of the structural units (I), (II), (III) and (IV) of the phosphated polycondensation product according to the invention can be varied within wide limits. It has proved to be advantageous that the molar ratio of the structural units [(I) + (II) + (III)]: (IV) 1: 0.8 to 3, preferably 1: 0.9 to 2 and particularly preferably 1: 0.95 to 1.2.

The molar ratio of the structural units (I): [(II) + (III)] is normally from 1:10 to 10: 1, preferably from 1: 7 to 5: 1 and more preferably from 1: 5 to 3: 1.

In a preferred embodiment, the molar ratio of the structural units (II): (III) to 1: 0.005 to 1: 10, further 1: 0.01 to 1: 1, in particular 1: 0.01 to 1: 0.2, and especially preferably 1: 0.01 to 1: 0.1.

The groups A and D in the structural units (I), (II) and (III) of the polycondensation product are usually replaced by phenyl, 2-hydroxyphenyl, 3-hydroxyphenyl, 4-hydroxyphenyl, 2-methoxyphenyl, 3-methoxyphenyl, 4- Methoxyphenyl, naphthyl, 2-hydroxynaphthyl, 4-hydroxynaphthyl, 2-methoxynaphthyl, 4-methoxynaphthyl preferably represents phenyl, where A and D can be selected independently of one another and can each consist of a mixture of said compounds. Groups B and E are preferably independently represented by O.

The radicals R ¹ , R ² , R ³ and R ⁴ can be selected independently of one another and are preferably represented by H, methyl, ethyl or phenyl, more preferably by H or methyl and especially preferably by H.

A in structural unit (I) is preferably represented by an integer from 5 to 280, in particular from 10 to 160 and more preferably from 12 to 120, and b in structural unit (II) and (III) by an integer from 0 to 10, preferably 1 to 7 and more preferably 1 to 5. The respective radicals, whose length is defined by a or b, may in this case consist of uniform assemblies, but it may also be expedient that it is a mixture of different components. Furthermore, the radicals of the structural units (I) or (II) and (III) may each independently have the same chain length, wherein a and b are each represented by a number. However, it will generally be expedient that they are each mixtures with different chain lengths, so that the radicals of the structural units in the polycondensation product have a different value for a and independently for b.

Frequently, the phosphated polycondensation product according to the invention has a weight-average molecular weight of 4000 g / mol to 150,000 g / mol, preferably 10,000 to 100,000 g / mol and particularly preferably 20,000 to 75,000 g / mol.

As a rule, the phosphated polycondensation product according to the invention is present in aqueous solution containing 2 to 90% by weight of water and 98 to 10% by weight of dissolved water. compound mass, preferably 40 to 80% by weight of water and 60 to 20% by weight of dissolved dry matter, more preferably 45 to 75% by weight of water and 55 to 25% by weight of dissolved dry matter. The dry mass then essentially consists of the anhydrous phosphated polycondensation product, but it may also be advantageous to include further components such as defoamers and other auxiliaries.

In a particular embodiment, the present invention further provides that it is a sodium, potassium, ammonium and / or calcium salt and, preferably, a sodium and calcium salt, of the phosphated polycondensation product.

The present invention also relates to a process for preparing a phosphated polycondensation product, wherein it is to be regarded as essential to the invention that the polycondensation and the phosphating are carried out in a reaction mixture. By this is meant that the phosphated component formed in the reaction solution is neither purified nor isolated. The phosphating can be carried out before, during or after the polycondensation. It is considered preferable to carry out both the phosphating and the polycondensation in the same reaction vessel.

In a preferred embodiment, the reaction mixture contains at least

(Ia) a monomer having a polyether side chain and an aromatic or heteroaromatic radical,

(lilac) a monomer containing an aromatic or heteroaromatic compound, where (lilac) is partially phosphated during the reaction and the monomer (IIa) and / or in the polycondensation product form the structural unit (IIa),

(IVa) a monomer having an aldehyde group and a phosphating agent,

wherein structural unit (IIIa) is other than structural unit (Ia).

The monomers (Ia), (IIa), (IIIa) and (IVa) and in the polycondensation product the structural unit (IIa) are preferably represented by the following general formulas

(Ia)

With

A is the same or different and is represented by a substituted or unsubstituted aromatic or heteroaromatic compound having 5 to 10 C atoms

With

B is the same or different and represented by N, NH or O.

with n = 2 if B = N and n = 1 if B = NH or O

With

R ¹ and R ^{2 are} independently the same or different and represented by a branched or unbranched d- to Cio-alkyl radical, Cs to Cs-cycloalkyl radical, aryl radical, heteroaryl radical or H.

with a the same or different and represented by an integer from 1 to 300

where X is identical or different and represented by a branched or unbranched C 1 to C 10 -alkyl radical, C 8 to C 8 -cycloalkyl radical, aryl radical, heteroaryl radical or H

für (IIa) und (lila) jeweils:(purple)

for (IIa) and (lilac) respectively:

With

D is identical or different and represented by a substituted or unsubstituted aromatic or heteroaromatic compound having 5 to 10 C atoms

With

E is the same or different and represented by N, NH or O.

with m = 2 if E = N and m = 1 if E = NH or O

with R ³ and R ^{4 are} independently the same or different and represented by a branched or unbranched d- to Cio-alkyl radical, Cs to Cs-cycloalkyl radical, aryl radical, heteroaryl radical or H.

with b being the same or different and represented by an integer from 0 to 300

mit R⁷ gleich oder verschieden und repräsentiert durch H, CH3, COOH und/oder eine substituierte oder unsubstituierte aromatische oder heteroaromatische Verbindung mit 5 bis 10 C-Atomen(IVa) O

where R ^{7 is} identical or different and represented by H, CH 3, COOH and / or a substituted or unsubstituted aromatic or heteroaromatic compound having 5 to 10 C atoms

where R ^{8 is} identical or different and represented by H, CH 3, COOH and / or a substituted or unsubstituted aromatic or heteroaromatic compound having 5 to 10 C atoms.

Various variants of the reaction procedure are provided by the present invention. One possibility is that the monomer (IIIa) is first reacted with a phosphating agent and the resulting monomer (IIa) is polycondensed with the monomers (Ia), (IIIa) and (IVa). The monomer (purple) can in this case originate from an incomplete reaction in the phosphating reaction or be added to the reaction mixture in a targeted manner after the phosphating reaction.

However, it is also possible to subject the monomers (Ia), (IIIa) and (IVa) to a polycondensation and to react the resulting polycondensation product subsequently with a phosphating agent. In a further embodiment, the monomers (Ia), (IIIa) and (IVa) and the phosphating agent are reacted simultaneously.

In particular, polyphosphoric acid and / or phosphorus pentoxide have proven suitable as phosphating agents.

In general, the polycondensation is carried out in the presence of an acidic catalyst, which is preferably sulfuric acid, methanesulfonic acid, para-toluenesulfonic acid or mixtures thereof.

The polycondensation and the phosphating are advantageously carried out at a temperature between 20 and 140 ⁰ C and a pressure between 1 and 10 bar. In particular, a temperature range between 80 and 110 ⁰ C has proven to be expedient. Depending on the temperature, the chemical nature of the monomers used and the desired degree of crosslinking, the reaction time can be between 0.1 and 24 hours. When the desired degree of crosslinking has been achieved, which can be determined, for example, by measuring the viscosity of the reaction mixture, the reaction mixture is cooled.

According to a particular embodiment, after completion of the condensation and phosphation reaction, the reaction mixture is subjected to a thermal aftertreatment at a pH between 8 and 13 and a temperature between 60 and 130 ^° C. Due to the thermal aftertreatment, which advantageously takes between 5 minutes and 5 hours, it is possible to significantly lower the aldehyde content, in particular the formaldehyde content in the reaction solution.

In a further particular embodiment, the present invention provides that to reduce the aldehyde content, the reaction mixture after completion of the condensation and phosphating a vacuum post-treatment at pressures between 10 and 900 mbar subjects. Furthermore, however, other methods known to those skilled in the art for reducing the formaldehyde content can also be used. An example is the addition of small amounts of sodium bisulfite, ethylene urea and / or polyethyleneimine. The resulting phosphated polycondensation products can be used directly as flow aids. In order to obtain better storage stability and better product properties, it is advantageous to treat the reaction solutions with basic compounds. It is therefore to be regarded as preferred to react the reaction mixture after completion of the reaction with a basic sodium, potassium, ammonium or calcium compound. Sodium hydroxide, potassium hydroxide, ammonium hydroxide or calcium hydroxide have proved to be particularly useful, it being considered preferable to neutralize the reaction mixture. As salts of the phosphated polycondensation but also other alkali and alkaline earth metal salts and salts of organic amines in question.

Furthermore, however, the present invention also provides for the preparation of mixed salts of the phosphated polycondensation products. These can be conveniently prepared by reacting the polycondensation products with at least two basic compounds.

Thus, by a targeted selection of suitable alkali and / or alkaline earth metal hydroxides by neutralization, salts of the polycondensation products according to the invention can be prepared with which the duration of processability of aqueous suspensions of inorganic binders and especially of concrete can be influenced. While, in the case of the sodium salt, a reduction in processability over time is observed, in the case of the calcium salt of the identical polymer, a complete reversal of this behavior occurs, with initially less water reduction (low slump) occurring, which increases with time. As a result, sodium salts of the phosphated polycondensation products over time reduce the processability of the binder-containing composition, e.g. Concrete or mortar lead, while the corresponding calcium salts over time lead to improved processability. By suitable choice of the amount of sodium and calcium salts of the phosphated polycondensation products used, it is thus possible to control the development over time of the processability of binders containing masses. Suitably, the corresponding phosphated polycondensation products, which consist of sodium and calcium salts, prepared by reaction with a mixture of basic calcium and sodium compounds, in particular calcium hydroxide and sodium hydroxide.

The catalyst used can also be separated in the context of the present invention. Appropriately, this can be done via the salt formed in the neutralization. When sulfuric acid is used as a catalyst and the reaction solution is treated with calcium hydroxide, the formed calcium sulfate can be easily separated by filtration, for example. Furthermore, by adjusting the pH of the reaction solution to 1, 0 to 4.0, in particular 1, 5 to 2.0, the phosphated polycondensation be separated by phase separation of the aqueous salt solution and separated. The phosphated polycondensation product can then be taken up in the desired amount of water.

For the separation of the catalyst, however, other methods known to those skilled in the art, such as dialysis, ultrafiltration or the use of an ion exchanger are also suitable.

Furthermore, the invention relates to a building material mixture comprising the phosphated polycondensation product according to the invention and a hydraulic binder and / or a latent hydraulic binder.

Typically, the hydraulic binder is present as cement, lime, gypsum, hemihydrate or anhydrite or as mixtures of these components, preferably as cement. The latent hydraulic binder is normally present as fly ash, trass or blast furnace slag.

Based on the weight of the inorganic binder, the phosphated polycondensation product in an amount of 0.01 to 10 wt .-%, in particular 0.05 to 5 wt .-%, is used.

Surprisingly, in the case of the phosphated polycondensation products according to the invention, it was possible to ascertain an improved activity, but at least a comparably good activity, compared to those polycondensation products known in the prior art.

In the case of the phosphated polycondensation products according to the invention, it has proven to be particularly advantageous that they can be prepared by a very cost-effective process, with no further purification of intermediates being necessary. In particular, in the method according to the invention, no waste materials must be disposed of. Thus, the claimed method also provides further progress in the state of the art from an environmental point of view. The resulting reaction mixture may, if appropriate after treatment with basic compounds, be supplied directly to the intended use as additive for building material mixtures. The underlying task is thus fully solved.

The present invention will be described in more detail below with reference to exemplary embodiments. It should be compared according to the invention phosphated polycondensation products (according to Preparation Examples 2 to 4) with polycondensation products, which are already successfully used in practice (according to Comparative Example 1) with respect to their performance.

Examples

Example 1 (comparative example)

A heatable reactor equipped with stirrer is charged with 600 parts of poly (ethylene oxide) monophenyl ether (average molecular weight 2000 g / mol), 58.9 parts of concentrated sulfuric acid, 39 parts of water, 194.4 parts of oligoethylene glycol monophenyl ether phosphoric acid ester (average molecular weight 324 g / mol) and 89.5 parts of 30% formaldehyde solution. The reaction mixture is heated with stirring for 4 hours at 1 10 ⁰ C. Then allowed to cool and neutralized with 50% sodium hydroxide solution to pH 7.

Example 2

A heatable reactor equipped with a stirrer is charged with 16 parts of polyphosphoric acid and heated to 105 ⁰ C. Within 15 minutes, 27.6 parts of phenoxyethanol are metered in with stirring. After 60 minutes, 400 parts of polyisocyanate

(ethylene oxide) monophenyl ether (average molecular weight 5000 g / mol), 31, 4 parts of concentrated methanesulfonic acid, 12.6 parts of paraformaldehyde and 20 parts of water. The reaction mixture is heated to 105 ^° C. with stirring for a further 6 hours. Then allowed to cool and neutralized with 50% sodium hydroxide solution to pH 7.

Example 3

And a heated reactor equipped with a stirrer is charged with 17.8 parts of polyphosphoric phoric acid and heated to 90 ⁰ C. Within 15 minutes, 30.7 parts of phenoxyethanol are added with stirring. After 60 minutes, 445 parts of poly (ethylene oxide) monophenyl ether (average molecular weight 5000 g / mol), 34.8 parts of concentrated methanesulfonic acid, 14.16 parts of paraformaldehyde and 23.2 parts of water are added. The reaction mixture is heated to 105 ^° C. with stirring for a further 6 hours. Then allowed to cool and neutralized with 50% sodium hydroxide solution to pH 7.

Example 4

A heatable reactor equipped with a stirrer is charged with 200 parts of polyethylene.

(ethylene oxide) monophenyl ether (average molecular weight 5000 g / mol), 1 1 parts of phenoxyethanol and 4.2 parts of paraformaldehyde filled. The reactor is heated to 90 ^° C. with stirring. 23.5 parts of methanesulfonic acid are added over a period of 30 min. After completion of the addition, the temperature is raised to 110 ° C and stirred for a further 6 hours at this temperature. Subsequently, 9.6 parts of poly phosphoric acid were added and stirred for 45 min at 80 ⁰ C. Then allowed to cool and neutralized with 50% sodium hydroxide solution to pH 7. Application test: Reduction of the water requirement of a mortar while maintaining the consistency.

Mixing process Mortar mixture:

600 g cement powder are dry homogenized and placed in a RILEM mixer. Then the amount of water required according to a W / Z value is added and mixed for 30 seconds at 140 rpm (step I). The addition of the sand mixture is then carried out while the mixer is running using a funnel and it is mixed for 30 s at 140 U / min (stage I). After a mixing break of 1.5 minutes, the edges of the mixer are cleaned and an appropriate amount of flow agent from Comparative Example 1 or Invention Examples 2, 3, and 4 is added. It is mixed for a further 60 s at 285 rpm (stage II) and then the flow rate (slump) determined by tapping on a tapping table with Hägermann cone 10 times (DIN EN 1015-3).

The dosage of the flow agent is kept constant and the water-cement ratio adjusted so that a slump of about 24 cm is obtained. A mortar based on Karlstadt CEM I 42.5 R and a sand-cement ratio of 2.2 is used. The sand consists of a mixture of 70% by weight of standard sand and 30% by weight of quartz sand.

The results of the application tests of the products obtained according to Examples 1 to 4 are shown in the following table:

Claims

claims 1) containing polycondensation product (I) at least one structural unit having an aromatic or heteroaromatic and a polyether side chain, and (II) at least one phosphated an aromatic or heteroaromatic containing structural unit and at least one structural unit having an aromatic or heteroaromatic compound, wherein structural unit (II) and structural unit (III) differ solely in that the OP (OH) 2 group of the structural unit (II) in structural unit (III) is replaced by H and structural unit (III) is not structural unit (I). 2) Polycondensation product according to claim 1, characterized in that the structural units (I), (II) and (III) are represented by the following general formulas (I)

With A is the same or different and represented by a substituted or unsubstituted aromatic or heteroaromatic compound having 5 to 10 C-atoms With B is the same or different and represented by N, NH or O. with n = 2 if B = N and n = 1 if B = NH or O With R ¹ and R ² independently of one another are identical or different and represented by a branched or unbranched C 1 - to C 10 -alkyl radical, C 5 - to C 8 -cycloalkyl radical, aryl radical, heteroaryl radical or H. with a the same or different and represented by an integer from 1 to 300 where X is identical or different and represented by a branched or unbranched C 1 to C 10 -alkyl radical, C 8 to C 8 -cycloalkyl radical, aryl radical, heteroaryl radical or H (II)

(IN)

for (II) and (III) respectively: With D is identical or different and represented by a substituted or unsubstituted aromatic or heteroaromatic compound having 5 to 10 C-atoms With E is the same or different and represented by N, NH or O. with m = 2 if E = N and m = 1 if E = NH or O With R ³ and R ⁴ independently of one another are identical or different and represented by a branched or unbranched C 1 - to C 10 -alkyl radical, C 5 - to C 8 -cycloalkyl radical, aryl radical, heteroaryl radical or H. with b being the same or different and represented by an integer from 0 to 300 3) Polycondensation product according to claim 1 or 2, characterized in that it contains a further structural unit (IV), which is represented by the following formula

With Y are independently the same or different and represented by (I), (II), (III) or further constituents of the polycondensation product With R ^{5 is} identical or different and represented by H, CH 3, COOH or a substituted or unsubstituted aromatic or heteroaromatic compound having 5 to 10 C atoms With R ^{6 is} identical or different and represented by H, CH 3, COOH or a substituted or unsubstituted aromatic or heteroaromatic compound having 5 to 10 C atoms. 4) Polycondensation product according to claim 3, characterized in that R ⁵ and R ⁶ in structural unit (IV) independently of one another identically or differently represented by H, COOH and / or methyl. 5) Polycondensation product according to one of claims 1 to 4, characterized in that the molar ratio of the structural units [(I) + (II) + (III)]: (IV) is 1: 0.8 to 3. 6) Polycondensation product according to one of claims 1 to 5, characterized in that the molar ratio of the structural units (I): [(II) + (III)] 1: 10 to 10: 1. 7) Polycondensation product according to one of claims 1 to 6, characterized in that the molar ratio of the structural units (II): (III) is 1: 0.005 to 1: 10. 8) A polycondensation product according to any one of claims 1 to 7, characterized in that the polycondensation product is in aqueous solution containing 2 to 90 wt .-% water and 98 to 10 wt .-% dissolved dry matter. 9) Process for the preparation of a phosphated polycondensation product, characterized in that the polycondensation and the phosphating are carried out in a reaction mixture. 10) Process according to claim 9, characterized in that a polycondensation product according to one of claims 1 to 8 is produced. 1 1) Process according to claims 9 or 10, characterized in that the reaction mixture at least (Ia) a monomer having a polyether side chain and an aromatic or heteroaromatic, (lilac) a monomer containing an aromatic or heteroaromatic compound, where (lilac) is partially phosphated during the reaction and the monomer (IIa) and / or in the polycondensation product form the structural unit (IIa), (IVa) a monomer having an aldehyde group and a phosphating agent contains, wherein structural unit (purple) is not the same structural unit (Ia). 12) Process according to claim 11, characterized in that the monomer (IIIa) is first reacted with a phosphating agent and the resulting monomer (IIa) is polycondensed with the monomers (Ia), (IIIa) and (IVa). 13) Process according to claim 11, characterized in that the monomers (Ia), (IIIa) and (IVa) are polycondensed and the resulting polycondensation product is subsequently reacted with a phosphating agent. 14) Process according to claim 11, characterized in that the monomers (Ia), (IIIa) and (IVa) and the phosphating agent are reacted simultaneously. 15) Use according to one of claims 1 to 8, as an additive for aqueous suspensions of hydraulic and / or latent hydraulic binders.