WO2014108436A1

WO2014108436A1 - Water-resistant binder based on calcium sulfate

Info

Publication number: WO2014108436A1
Application number: PCT/EP2014/050214
Authority: WO
Inventors: Stephan Auer; Martin SCHÖTTELDREIER; Wolfgang Hagen
Original assignee: Henkel Ag & Co. Kgaa
Priority date: 2013-01-08
Filing date: 2014-01-08
Publication date: 2014-07-17
Also published as: DE102013200122A1; EP2943445A1

Abstract

The invention relates to a binder composition comprising (a) calcium sulfate, (b) Portland cement, (c) calcium aluminate cement, (d) zeolite and/or metakaolin, the quantity of calcium sulfate contained in the composition being ≥ 50 parts by weight, in relation to a total quantity of 100 parts by weight, formed from the four components (a) calcium sulfate, (b) Portland cement, (c) calcium aluminate cement and (d) zeolite and/or metakaolin. The invention also relates to chemical construction products containing the binder composition and to a method for using said binder components and chemical construction products.

Description

Water-resistant binder based on calcium sulfate

The invention relates to binders, as well as construction chemical products. The invention particularly relates to binders comprising calcium sulfate, Portland cement,

Calcium aluminate cement, and zeolite and / or metakaolin included.

Calcium sulfate-containing binder compositions are known in the art. For example, European Patent Application EP 0 849 237 A1 describes compositions based on calcium sulfate hemihydrate, Portland cement and metakaolin. These are versatile, but for some applications still have no sufficient water resistance.

DE 10 2005 004 362 C5 discloses tile adhesive compositions with lightweight filler and process for their preparation. These are hydraulically setting systems which contain at least one hydraulically setting component, at least one light filler, at least one cellulose ether and at least one setting retarder in specific weight ratios. Furthermore, a number of additives may be included. A long list of suitable additives includes pozzolans such as metakaolin. The hydraulically setting component is Portland cement and / or high-alumina cement, which may additionally contain calcium sulfate and / or lime. Main component of the binder component is disclosed in all concrete

Recipes a cement or cement mixture. A disadvantage of cement-based systems is the high energy requirement in the production of cements. Such an energy-intensive process is not desirable for environmental reasons, especially with regard to the so-called C0 ₂ footprint.

EP 1 609 770 A2 describes hydraulically setting adhesive mortars comprising from 10 to 70% by weight of a hydraulic binder, from 1 to 70% by weight.

Additives based on pozzolanic and / or latent hydraulic additives, 10 to 80 wt .-% fillers, various additives and water. The hydraulic binder is preferably Portland cement and / or alumina cement. Only in addition, the addition of lime and / or gypsum is provided. Again, the major component of the binder component is in all Specifically disclosed formulations a cement or cement mixture. Gypsum is not used in it.

EP 1 274 664 B1 discloses non-blooming cement bodies and hydraulic binders for forming a non-corrosive cementitious body. The latter include an active silica source, a source of calcium aluminate, e.g. Calcium aluminate cement, a source of calcium silicate, e.g. Portland cement, and a source of sulfate, e.g. Calcium sulfate, in predetermined proportions. Based on the total amount of these components, the source of sulfate may be at most 45% by weight. All examples according to the invention contain cements as the main constituent. When anhydrite is used as a main component, the desired properties are not achieved (Comparative Examples 5 and 7).

The object of the present invention was to provide other water-resistant binders based on calcium sulfate, which meet in particular increased requirements for water resistance and in particular quickly set and fast drying and also characterized by the most favorable C0 ₂ -Fußabdruck.

This object is solved by the subject matter of the invention. This is a binder composition, in particular pulverulent composition comprising

(a) calcium sulphate,

(b) Portland cement,

(c) calcium aluminate cement,

(d) zeolite and / or metakaolin,

wherein calcium sulfate is contained in an amount of> 50 parts by weight based on a total amount of 100 parts by weight formed from the four components (a) calcium sulfate, (b) Portland cement, (c) calcium aluminate cement, (i.e. ) Zeolite and / or metakaolin.

This binder composition is advantageously characterized by the fact that it hardens under water uptake in air after addition of the necessary mixing water and is water-resistant after curing and leads to a very waterproof building material. Make-up water (also called addition water) refers to the water that must be introduced in the mixing and processing of the binder composition in order to make them processable and to start the setting process. The total amount of water in the

Mixture is composed of the amount that enters the mixture with the optional aggregate material (preferably sand, gravel) and the addition water. Addition water is only added in such an amount that the consistency required for processing is achieved. The amount of the addition water can be determined by a person skilled in the art easily by a few hand tests. In the case of factory-made construction mixed dry mortar, the quantity of mixing water is specified by the manufacturer on the respective accompanying technical documents.

The water resistance manifests itself in that the physical strength properties of the cured binder are maintained in contact with water. The long-term use characteristics are not in contact with water

impaired. The binder composition according to the invention is therefore also readily usable outdoors and withstands weathering. The standardized minimum requirements for construction chemicals containing the compositions of the invention are also met. For example, in the binder compositions of the invention

resulting tile adhesives meet the standardized minimum requirements according to DIN EN 12004: 2007 on the adhesion tensile strength values after dry storage (measured according to test method EN 1348: 2007, 8.2), after water storage (measured according to

Test method EN 1348: 2007, 8.3), after warm storage (measured according to

Test method EN 1348: 2007, 8.4) and after freeze-thaw storage (measured according to test method EN 1348: 2007, 8.5). This minimum requirement is> 0.5 N / mm ² adhesive tensile strength measured according to the 4 types of storage mentioned. Of the resulting binder compositions of the invention

Tile adhesives even fulfill the increased requirements of> 1.0 N / mm ² adhesive tensile strength, measured according to the four types of storage mentioned in said standard EN 12004: 2007. Tile adhesives fulfill the criteria of class "C2".

Furthermore, the tile adhesives resulting from the binder compositions according to the invention fulfill the requirement for fast hardening mortars of> 0.5 N / mm ² adhesive tensile strength (class "F") measured after 6 hours at the latest according to test methods EN 1348: 2007, 8.2. In addition, in addition to this good early strength further positive application properties of calcium sulfate, such as in particular easy processability and low shrinkage.

It has surprisingly been found that just the combination of calcium sulfate, Portland cement, Calciumaluminatzement (especially with an Al ₂ 0 ₃ content> 25 wt .-%), and as a fourth component zeolite and / or

Metakaolin leads to particularly good results, what application and

Material properties concerns.

An advantage of the invention is that the composition according to the invention cures very rapidly with water absorption and exhibits a high early strength. The water resistance of the resulting building material as well as its surface finish and resistance to extreme natural

Weather and temperature influences are excellent. The resulting

Building materials show excellent long-term stability.

A further advantage is that the composition according to the invention cures very quickly, even at low temperatures, with absorption of water. The

Hardening time at 5 ° C is surprisingly in comparison to the curing time at 23 ° C for a maximum of twice as long.

Yet another advantage is that the resulting waterproof building material shows at most a very low shrinkage, which is about 5 to 10 times lower than that of building materials based on pure Portland cement.

Yet another advantage is that the composition of the invention is much brighter in color impression than ordinary gray Portland cement. Should a darker color impression be sought, the e.g. easy to achieve by adding carbon black.

Another advantage is that the compositions according to the invention and the construction-chemical products containing them show excellent processability after mixing with the mixing water. In particular, products based on the binder composition of the present invention have significantly reduced dusting compared with the conventional products. According to the invention, construction-chemical products are understood as meaning compositions which, in addition to a binder composition, have at least 10 parts by weight, preferably at least 35 parts by weight, based in each case on the

Total weight of the construction chemical product, containing at least one aggregate. Suitable additives are mentioned below.

It is particularly advantageous, as already explained above with reference to the example of tile adhesive, that the compositions according to the invention also meet increased requirements for water resistance and, in particular, set particularly quickly and dry quickly.

The compositions of the invention are outstanding as

Binders in construction chemicals such as e.g. Tile adhesive, joint mortar, anchor mortar, plaster and masonry mortar, adhesive and reinforcing mortar for

External Thermal Insulation Composite Systems:

"ETICS"), screeds and self-leveling floor leveling compounds, and after adding appropriate aggregates, especially quartz sand, when mortaring, anchoring, paving, plastering or coating of interior or exterior surfaces, such as building walls or ceilings and repairing surfaces, eg filling of Cracks in walls or floors, as well as pour into molds.

Another advantage is that the use of hydrophobing agents, such as stearates of calcium or zinc, which impart hydrophobicity, can be dispensed with. Preferably, construction-chemical products according to the invention are free from hydrophobicizing agents.

The composition of the invention comprises as compelling constituents (a) calcium sulfate, (b) Portland cement, (c) calcium aluminate cement, in particular with an Al ₂ O ₃ content> 25 wt .-%, and as component (d) zeolite and / or metakaolin. It is especially in dry, powdered form.

The calcium sulfate is preferably selected from anhydrite, calcium sulfate hemihydrate and mixtures thereof.

CaS0 ₄ 2H ₂ 0 ^■ commonly known as gypsum. Dehydration of gypsum leads to calcium sulfate hemihydrate and anhydrite. The calcium sulfate hemihydrate is divided into alpha-calcium sulfate hemihydrate and beta-calcium sulfate hemihydrate. In this case, the alpha-calcium sulfate hemihydrate is preferred according to the invention. But also beta-calcium sulfate hemihydrate can be used successfully.

Alpha-calcium sulfate hemihydrate (α-CaSCyO.δH ₂ O) is known per se to the person skilled in the art and is commercially available. Various methods are available in the prior art which lead to alpha-calcium sulfate hemihydrate. These processes can be divided into dry and wet processes. The wet processes are based essentially on the production of alpha-calcium sulfate hemihydrate from an aqueous suspension. For example, alpha-calcium sulfate hemihydrate can be prepared by dehydrating gypsum in water at elevated temperatures, eg, 100 to 150 ° C, and under elevated pressure, or by conversion in an atmosphere of saturated steam under elevated pressure in a pressure vessel such as an autoclave become. For example, German Patent DE 3634204 C1 describes a process for the production of alpha-calcium sulfate hemihydrate. Corresponding drying methods are likewise known from the literature.

The alpha-calcium sulfate hemihydrate is used in particular in powder form. The average particle size d50 is preferably less than 100 μm, advantageously less than 60 μm, and in particular more than 0.5 μm and less than 50 μm, e.g. in the range of 5 μηη to 45 μηη, in particular in the range 15 to 40 μηη. In this case, "mean particle size d 50 = a μηη" means that 50% by weight of the particles of the considered good have a diameter greater than a μηη and 50% by mass have a smaller diameter than α μηη Principle of the analysis of the diffraction of incoherent light on

Particle current operating, sold by Retsch Technology Instrument Crystalsizer determined.

The values d10 and d90 indicate a particle size at which 10% by mass and 90% by mass of the particles are smaller than the specified value. These values are also determined with the Crystalisizer meter. The particle size d10 of the alpha-calcium sulfate hemihydrate is preferably below 20 μηη, it is advantageously 0.5 μηι to 15 μηι and in particular 0.5 μηι to 10 μηι, eg 2 to 8 μηι.

The particle size d90 of the alpha-calcium sulfate hemihydrate is preferably less than 100 μηι, it is advantageously 20 μηι to 90 μηι and in particular 30 μηι to 85 μηι, e.g. 40 to 80 μηι.

The use of alpha-calcium sulfate hemihydrate of the type described above leads to particularly good application and material properties, in particular with regard to water resistance, early strength, processability and the lowest possible shrinkage.

The beta-calcium sulfate hemihydrate is also used in particular in powder form. The mean particle size d50 is preferably less than 50 μm, advantageously less than 30 μm, and in particular more than 1 μm and less than 20 μm, e.g. in the range of 2 μηη to 15 μηη.

Anhydrite is known to those skilled in the art and is in its natural form as

Anhydrite-Il present in numerous deposits. These are calcium sulphate free of water of crystallization. Anhydrite is a sediment mineral that has so far been detected in over 1000 natural sites. For the purposes of the invention, the so-called anhydrite-II, also called crude anhydrite, .beta.-anhydrite and natural anhydrite is particularly preferred.

In addition to the natural occurrence of anhydrite can also be obtained in technical processes. In fact, it can be obtained by heating gypsum, CaS0 ₄ ^■ 2H ₂ 0. When gypsum is heated to 120 to about 180 ° C, the hemihydrate is initially formed. When heated to 180-240 ° C, the residual water of crystallization is expelled to a level of about 1%. This produces anhydrite III.

Further heating to 240 to 600 ° C leads to complete expulsion of the water of crystallization. It produces anhydrite II. Typical examples of technical formation temperatures are at 350 ° C or 400 ° C up to 800 ° C.

According to the invention, both anhydrite III, and anhydrite II, as well as their mixtures can be used. However, it corresponds to a preferred one

Embodiment to use anhydrite II, in particular in a particle size d50 from 3-40 μηη, in particular 5-30 μηι. Anhydrit II may be a natural product that has been treated, or made synthetically.

Anhydrite II from natural sources (natural anhydrite) is most preferred.

Anhydrite is used in particular in powder form. The mean particle size d50 is preferably less than 100 μm, advantageously less than 50 μm and in particular more than 3 μm and less than 40 μm. A particle size d50 of 5-30 μm is particularly preferred. In this case, "average particle size d50 = a μηη" means that 50% by weight of the particles of the considered good have a diameter greater than a μηη and 50% by mass have a smaller diameter than a μηη

Particle size is calculated after the o.g. Method determined.

The use of anhydrite, in particular natural anhydrite, of the type described above leads to particularly good application and material properties, in particular with regard to water resistance, early strength, processability and

lowest possible shrinkage.

According to the invention, it is particularly preferred if the calcium sulfate used is alpha-calcium sulfate hemihydrate or anhydrite. Very particular preference is given to using alpha-calcium sulfate hemihydrate. In particular, when using anhydrite, it is further preferred, the composition an additional

Add sulfate salt. Suitable additional sulfate salts and their preferred amounts are described below.

The calcium sulfate is in the binder composition of the invention preferably in an amount of 60 to 98 parts by weight, preferably 60 to 97.9 parts by weight, in particular 60 to 89 parts by weight, particularly preferably 60 to 75 parts by weight and most preferably 60 to 74 parts by weight, based on a total amount of 100 parts by weight, which is formed from the four components (a) calcium sulfate, (b) Portland cement, (c) calcium aluminate cement, (d) zeolite and / or metakaolin.

For the purposes of this invention, the term "Portland cement" generally stands for a cement which hardens underwater absorption especially in a conventional manner by heating a slurry of clay and calcium carbonate. The standard DIN EN 197-1: 201 1

distinguishes the following types of cement CEM I to CEM V, namely

CEM I Portland Cements,

CEM II Portland composite cements,

CEM III blast furnace cements,

CEM IV pozzolana cement,

CEM V composite cements.

In particular, these types of cement CEM I to CEM V of the standard DIN EN 197-1: 201 1 are encompassed by the term "Portland cement." The cement types that can be used each include Portland cement clinker Slate, limestone and other minor constituents The constituents of the cement types are defined by the standard DIN EN 197-1: 201 1. For example, the cement type CEM I has 95-100 mass% Portland cement clinker

Preferred types of cement within the meaning of the invention are the types CEM I to CEM V with a Portland cement clinker content> 40 mass%. Particularly preferred are the types CEM I and CEM II.

The grinding fineness of the usable Portland cement, expressed as Blaine value, is preferably> 2500 cm ² / g. The Blaine value is a standard measure of the degree of fine grinding of cement, preferably determinable according to EN 196-6. It is given as the laboratory specific Blaine device specific surface area (cm ² / g). The determination of the Blaine value is known in the art and described in detail in the literature, eg "The testing of the fineness of the Blaine device", Volume 7 of series of the cement industry, author: Fritz Gille, Bauverlag 1951.

The Portland cement is used in particular in powder form. The mean particle size d50 is preferably less than 50 μm, advantageously less than 30 μm and in particular between 0.5 μm and <25 μm. In this case, "mean particle size d 50 = a μηη" means that of the material under consideration 50% by weight of the particles have a diameter greater than a μηη and 50% by mass have a smaller diameter than a μηη The mean particle size is determined by the above-mentioned method certainly. The use of Portland cement of the type described above, in particular with regard to particle size d50 and Blaine value in turn leads to particularly good

Application and material properties, especially with regard to water resistance, early strength, processability and lowest possible shrinkage.

Calcium aluminate cement is known to the person skilled in the art. The calcium aluminate cement is, in particular, calcium aluminate cement with an Al ₂ O ₃ content> 25% by weight. Calcium aluminate cement for the purposes of this invention are in particular alumina cement, as well as calcium sulfoaluminate cement.

Alumina cement is known per se to the person skilled in the art. This may in particular consist of bauxite and limestone by sintering and melting, e.g. at approx. 1500-1600 ° C. Preferably usable alumina cement consists mainly of calcium aluminate with preferably> 25 wt .-%, in particular about 30-80 wt% alumina, preferably about 35-40 wt .-% calcium oxide, preferably about 0-15 wt .-% Iron (III) oxide and preferably about 0-8% by weight of silica.

As the main mineralogical phase, the preferably usable alumina cement contains the so-called monocalcium aluminate CaO-Al ₂ O ₃ (CA).

Preferably, for example, C ₄ AF (tetracalcium ferroaluminate), C ₁₂ A ₇ (Dodecacalcium hepta-aluminate), C ₂ AS (gehlenite), CT (CaO-Ti0 ₂ ), alpha - Al ₂ 0 ₃ and CaO ₂ Al ₂ 0 ₃ (CA 2) occur as secondary phases.

The preferred chemical composition of the alumina cement may be

for example, with the following main components:

Al ₂ O ₃ 35-80 wt.%,

CaO 20-45% by weight,

Si0 ₂ 0-15%, preferably 0, 1 - 10 wt .-%,

Fe ₂ 0 ₃ 0-15%, preferably 0, 1 - 20 wt .-%.

As further components, in particular MgO, Ti0 _2, K ₂ 0, Na ₂ 0 and S0 ₃ may be included, preferably in amounts <1 wt .-%.

An inventively preferably usable alumina cement contains in particular at least 35 wt .-% Al ₂ 0 ₃ and has as the main mineralogical phase CA.

(Monocalcium aluminate, CaOAl ₂ 0 ₃ ). As secondary phases, for example C ₁₂ A ₇ (12 CaO-7Al ₂ 0 ₃ ), C ₂ AS (2CaO-Al ₂ 0 ₃ -SiO ₂ ), C ₄ AF (tetracalcium ferroaluminate), CT (CaO-TiO ₂ ), alpha-Al ₂ 0 ₃ or CaO-2Al ₂ 0 ₃ (CA2) occur.

The grinding fineness of the alumina cement, expressed as Blaine value, is preferably> 2500 cm ² / g.

Calcium sulfoaluminate cement is known in the art. Calcium sulfoaluminate cement is characterized in particular by the fact that the so-called "small ^" compound, ie Yeelimite (4CaO-3Al ₂ 0 ₃ -S0 ₃ ; C4A3S), forms the main mineral phase.

The fineness of the calcium sulfoaluminate cement, expressed as Blaine value, is preferably> 4000 cm ² / g.

The preferred Al ₂ O ₃ content of the calcium sulfoaluminate cement is> 20% by weight, preferably greater than 25% by weight, for example in the range from 25 to 35% by weight or for example in the range from 40 to 50% by weight. -%.

The addition of the calcium aluminate cement improves the drying properties of the binder composition and construction chemical products based thereon. Studies of tile adhesives based on inventive binder compositions according to the so-called Darr test method prove that with increasing amount of calcium aluminate cement the drying process is accelerated and a lower residual water content can be achieved.

The Darr test method simulates the drying of a tile adhesive mortar under unfavorable drying conditions, i. under conditions that no

allow physical drying, as e.g. occur when laying tile on tile, both tiles have a water absorption of practically 0. To carry out the test, the tile adhesive to be examined is mixed with 25% by weight of water to give a processing-based consistency. From this, a disk-shaped mortar cake with a diameter of 100 mm and a thickness of 10 mm is then formed, which is immediately transferred into a water-vapor-tight HDPE bag. The bag is closed so that no water vapor can escape. Then the bags are stored at 23 ° C for a given period of time, for example 1, 3, 7 and 28 days. After reaching the respective

Storage time, the bag is opened and the cured mortar cake weighed and then dried in a ventilated oven at 40 ° C for 24 hours. After 24 h, the dried mortar cake is weighed again and calculated the weight difference in%. This difference corresponds to the free non-crystalline bound water.

Zeolites are also known per se to the person skilled in the art. These are crystalline aluminosilicates. Currently more than 150 natural and synthetic zeolites are known. According to the invention, both natural and synthetic zeolites can be used. Natural zeolites are preferred. These can be classified according to their crystal lattices into fiber zeolites (in particular comprising natrolite, laumontite, mordenite, thomsonite), zeolite zeolites (in particular comprising

Heulandite, stilbite, phillipsite, harmotom, yugawaralith) and cube zeolites

(in particular, including faujasite, gmelinite, chabazite, offretite, levyn). In the context of the invention, foliar zeolites of the heulandite group, in particular clinoptilolite, are particularly preferred.

The zeolite is used in particular in powder form. The average particle size d50 of the zeolite is preferably below 100 μm, advantageously below 50 μm and in particular above 0.5 μm and below 15 μm. In this case, "mean particle size d 50 = a μηη" means that of the material under consideration 50% by weight of the particles have a diameter greater than a μηη and 50% by mass have a smaller diameter than a μηη The mean particle size is determined by the above-mentioned method certainly.

The zeolite preferably contains natural zeolite in the binder compositions according to the invention, preferably zeolites of the heulandite group, in particular clinoptilolite, preferably zeolites, the average particle size d50 of the zeolite preferably being less than 100 μm,

advantageously less than 50 μηη and in particular more than 0.5 μηη and less than 15 μηη. This embodiment also leads to particularly good application and

Material properties, in particular with regard to water resistance,

Early strength, processability and lowest possible shrinkage.

Metakaolin is a product that results from the burning of kaolin and kaolinite clay. The pozzolanic activity is preferably such that the reactivity of the

Metakaolin with calcium hydroxide> 500 mg, preferably> 700 mg and

in particular> 1000 mg calcium hydroxide per g. The metakaolin can preferably by firing a kaolinite clay at a temperature of 450 to 900 ° C. The reactivity of a metakaolin with calcium hydroxide can be determined in particular by a method which is referred to in the field of concrete technology and in the literature as "chapelle test." In this regard and for the selection of particularly suitable metakaolines, reference is made to the already mentioned EP 0 849 237 A1 and also to the cited references to the pozzolanic reactivity of a metakaolin.

The metakaolin is used in particular in powder form. The mean particle size d50 is preferably below 20 μm, advantageously below 10 μm and in particular above 0.5 μm and below 5 μm. In this case, "mean particle size d 50 = a μηη" means that of the material under consideration 50% by weight of the particles have a diameter greater than a μηη and 50% by mass have a smaller diameter than a μηη The mean particle size is determined by the above-mentioned method certainly.

The present invention also enables the use of mixtures of metakaolin and zeolite (preferably natural zeolite, advantageously selected from foliar zeolites, preferably zeolites of the heulandite group, in particular clinoptilolite), e.g. in the mass ratio metakaolin to zeolite of 10: 1 to 1:10 or for example 5: 1 to 1: 5 or for example 2: 1 to 1: 2. Alternatively, either only metakaolin or only zeolite can be used.

The binder compositions according to the invention preferably comprise zeolite, preferably natural zeolite, advantageously selected from foliar zeolites, preferably zeolites of the heulandite group, in particular clinoptilolite, or a mixture of zeolite and metakaolin. If a mixture of zeolite and metakaolin is used, it is preferred that the mass ratio of metakaolin to zeolite is less than one.

The Portland cement is preferably contained in the binder composition of the present invention in a total amount of 1 to 45 parts by weight, preferably 5 to 30 parts by weight, especially 8 to 20 parts by weight, more preferably 10 to 20 parts by weight, and more particularly preferably 1 to 20 parts by weight, based on a total amount of 100 parts by weight, formed from the four components (a) calcium sulfate, (b) Portland cement, (c) calcium aluminate cement, (d) zeolite and / or metakaolin , Calcium aluminate cement, in particular alumina cement, is preferably present in the binder composition according to the invention in an amount of> 0.1 part by weight, preferably in an amount of from 1 to 45 parts by weight, more preferably 1 to 30 parts by weight, in particular 1, 5 to 20 parts by weight, more preferably 2 to 12 parts by weight and most preferably 5 to 12 parts by weight, based on a total amount of 100 parts by weight, formed from the four components (a) calcium sulfate , (b) Portland cement, (c) calcium aluminate cement, (d) zeolite and / or metakaolin.

Zeolite and / or metakaolin is preferably present in the binder composition according to the invention in a total amount of 1 to 30 parts by weight, preferably 5 to 25 parts by weight, in particular 8 to 20 parts by weight, particularly preferably 10 to 20 parts by weight , based on a total amount of 100 parts by weight, formed from the four components (a) calcium sulfate, (b) Portland cement, (c) calcium aluminate cement, (d) zeolite and / or metakaolin.

Accordingly, a binder composition comprising

(a) calcium sulfate in an amount of> 50 parts by weight,

(b) Portland cement in an amount of 1 to 45 parts by weight,

(c) calcium aluminate cement in an amount of 0.1 to 45 parts by weight,

(d) zeolite and / or metakaolin in an amount of from 1 to 30 parts by weight, based in each case on a total amount of 100 parts by weight, of the four components (a) calcium sulfate, (b) Portland cement, (c) Calcium aluminate cement, (d) zeolite and / or metakaolin, a preferred embodiment of the invention.

The composition of the invention can exclusively from the 4

Components (a) calcium sulfate, (b) Portland cement, (c) calcium aluminate cement, in particular alumina cement, (d) zeolite and / or metakaolin. However, it is also possible that the composition contains further additives.

The present invention also allows the use of mixtures of

Metakaolin and zeolite, eg in the mass ratio metakaolin to zeolite of 10: 1 to 1:10 or for example 2: 1 to 1: 5 or for example 1: 1 to 1: 2. A preferred composition according to the invention thus comprises calcium sulfate, Portland cement, calcium aluminate cement, in particular alumina cement, zeolite and metakaolin. This embodiment may also comprise further additives.

The composition according to the invention can, especially in the case where an anhydrite is used as CaSO ₄ , still contain additional sulfate salt, preferably alkali metal sulfate, in particular potassium sulfate, iron (II) sulfate, and / or aluminum sulfate, preferably in an amount of 0, 1 to 10 parts by weight, in particular 1 to 5 parts by weight, based on a total amount of 100 parts by weight, formed from the five components (a) calcium sulfate, (b) Portland cement, (c) calcium aluminate cement (in particular alumina cement ), (d) zeolite and / or metakaolin, (e) additional sulfate salt.

Preferably, the additional sulfate salt is selected from potassium sulfate, aluminum sulfate and mixtures thereof.

In addition to or instead of said additional sulfate salt, CaO may also be added as an additive, preferably in the amounts previously mentioned for the additional sulfate salt.

Since the binder compositions according to the invention, after addition of water, i. The "Anmachen", which initially form plastic mixtures, stone-harden in air and are water-resistant after curing, they can be used as binders in any construction chemical compositions, preferably containing conventional aggregate material, such as quartz sand and / or limestone sand, in particular The purpose is to join two objects together so that a water-tight bond between the objects can be obtained.The objects can be any known objects, such as bricks, blocks, mosaics, plates, insulation boards, natural stones, tiles, tiles, etc. Also, anchorages of pipes and metal elements are possible.

The binder composition according to the invention can in principle be used in all conventional construction chemical dry mortar products, such as e.g. Tile adhesive compositions, grout compositions,

Repair mortar compositions. The binder composition of the invention can also be used for the purpose of providing a water-resistant outer surface on an article. For this purpose, first a mixture of the inventive

Composition and water provided. The initially plastic mixture solidifies in the sequence to a water-resistant, hard building material, in which water is bound both chemically and adsorptively.

In this way, e.g. Also, an object such as a plasterboard or an object with a simulated stone effect are produced.

Thus, a composition of the invention which is added to water and which gives a hydrated building material composition which is water resistant after curing constitutes a preferred embodiment of the invention.

Another object of the invention is a hydrated building material composition,

full

(i) water and

(ii) a mixture of components (a) CaSO ₄ , (b) Portland cement, (c)

Calcium aluminate cement, in particular alumina cement, (d) zeolite and / or metakaolin,

preferably in the mass ratio (i) to (ii) of 0.2: 1 to 1: 1, in particular 0.35: 1 to 0.7: 1. This hydrated building material may also contain one or more additives that can be used in the preparation of cementitious compositions.

Additives may be added as part of the dry binder composition or building chemical composition or separately. Suitable, optionally usable additives are mentioned below.

Another object of the present invention is a construction chemical product, preferably selected from tile adhesive, grout, plaster, masonry mortar, screed mortar, repair mortar, anchor mortar, self-leveling floor leveling compound, adhesive and reinforcing mortar for external thermal insulation composite systems ("etics"), wall and floor leveling compounds, sealing slurries comprising from 1 to 90% by weight, preferably from 10 to 70% by weight, in particular 20-55% by weight of a binder composition according to the invention.

Another object of the invention is a method for using a composition according to the invention or a construction chemical product as described above as a binding material between at least two objects, comprising applying and hardening the water-made composition or the water-mixed construction chemical product to form a water-resistant Bond between the objects.

Another object of the invention is a method for using a composition according to the invention or a construction chemical product as described above, comprising applying and hardening the water-tipped composition or the tapped water-mixed product to form a water-resistant outer surface.

Suitable construction chemical products are particularly suitable as fine powders, which are then applied on site or at the specific site with water.

Construction chemical products according to the invention contain, in addition to the abovementioned binder according to the invention, at least one aggregate, in particular selected from quartz sand, limestone, limestone flour, thickener (for example based on layered silicates or starch ethers), water retention agents (e.g.

Cellulose ether), dispersion powder (eg EVA powder), hardening accelerator (eg alkali carbonates, alkali metal sulphates, calcium sulphate dihydrate), retarders, liquefiers and defoamers.

Construction chemical products according to the invention may also contain lightweight aggregates. These lightweight aggregates typically have densities of less than 2000 kg / m ³ , preferably less than 1500 kg / m ³ , very particularly preferably less than 1200 kg / m ³ or even less than 1000 kg / m ³ . Suitable for this purpose are, for example, hollow microspheres made of glass, ceramic or plastic, expanded glass, expanded mica, expanded perlite, expanded slate, expanded clay, hard coal fly ash, brick chippings, natural pumice, tuff, lava, granulated pumice and boiler sand. It can also be combined with each other two or more of these different lightweight aggregates become. The use of these lightweight aggregates is advantageous because this can reduce the specific weight of the overall formulation.

Construction chemical products according to the invention, in particular in the form of

powdery compositions, for example, the following

Contain ingredients, the following quantities are each based on the construction chemical products:

Binder according to the invention: from 10 to 80% by weight, preferably from 15 to 65% by weight, preferably from 20 to 55% by weight,

Optionally quartz sand and / or limestone sand: 0 to 70% by weight, preferably 1 to 65% by weight, in particular 10 to 60% by weight,

Optionally limestone flour: 0 to 75% by weight, preferably 1 to 65% by weight, in particular 10 to 60% by weight,

Optionally thickening agents, such as inorganic thickeners (e.g.

Silicic acid, layered silicates), organic thickeners (e.g., starch ethers), modified natural products (e.g., vegetable fibers), organic fully synthetic thickeners (e.g.

Polyvinyl alcohols, polyacrylamides): 0 to 3% by weight, in particular 0.2 to 1% by weight

%

Optionally water retention agents such as methylcellulose (e.g.

Methylhydroxyethylcellulose, methylhydroxypropylcellulose,

Ethylhydroxyethylcellulose, hydroxyethylcellulose): 0 to 3% by weight, in particular 0 to 1% by weight,

If appropriate, dispersion powder: 0 to 15% by weight, preferably 0.1 to 10% by weight, in particular 0.5 to 6% by weight,

If necessary (hardening) accelerator, such as potassium sulfate,

Aluminum sulfate, iron (II) sulfate, sodium carbonate: 0 to 3% by weight, in particular 0, 1 to 2% by weight,

Defoamers if necessary: 0 to 2% by weight, in particular 0.1 to 1% by weight,

Optionally lightweight aggregates: 0 to 50% by weight, preferably 2 to 45% by weight, in particular 3 to 40% by weight,

Optionally retarders, such as, for example, citric acid, tartaric acid, sodium gluconate: 0 to 3% by weight, in particular 0.01 to 0.5% by weight,

Optionally fibers which consist, for example, of glass and / or thermoplastic materials: 0 to 7% by weight, preferably 0 to 1 to 5% by weight,

Optionally dyes, for example pigments, such as iron oxides; eg 0.001 to 5% by weight, Optionally other inorganic particulate materials having pozzolanic properties, such as fine siliceous materials, fly ash, blast furnace slag, diatomaceous earth: 0 to 30% by weight, preferably 2 to 20% by weight, especially 5 to 15% by weight

Optionally flow-promoting agents (liquefiers), for example carboxylate-based polymers, polyacrylic acids and their salts, lignosulphonate salts and sulphonated melamine or naphthalene formaldehydes: 0 to 2% by weight, in particular 0.01 to 1% by weight,

If necessary, paraffin oils, white oil: 0 to 5% by weight, preferably 0.01 to 2% by weight.

A preferred tile adhesive comprises:

Alpha-calcium sulfate hemihydrate: 20 to 45% by weight,

Portland cement CEM I: 2 to 10% by weight,

Zeolite (preferably clinoptilolite) and / or metakaolin: 2 to 25% by weight,

Calcium aluminate cement (in particular alumina cement (with Al ₂ O ₃ about 70% by weight)): 1 to 5% by weight,

Quartz sand: 40 to 70% by weight,

Redispersible polymer powder (in particular vinyl acetate-ethylene copolymer-based): 0, 1 to 10% by weight,

Water-retaining agent: 0.1 to 1% by weight,

Retarder: 0.01 to 1% by weight.

A preferred grout comprises:

Alpha-calcium sulfate hemihydrate: 20 to 40% by weight,

Portland cement CEM I: 2 to 10% by weight,

Zeolite (preferably clinoptilolite) and / or metakaolin: 2 to 20% by weight,

Quartz sand: 40 to 70% by weight,

Limestone flour (d50 preferably 5 to 15 μηη): 0 to 20 wt .-%,

Redispersible polymer powder (in particular vinyl acetate-ethylene copolymer-based): 0, 1 to 5% by weight,

Water retention agent: 0.01 to 1 wt%,

Retarder: 0.01 to 1% by weight.

A preferred plaster and masonry mortar comprises:

Alpha-calcium sulfate hemihydrate: 10 to 30% by weight, Portland cement CEM I: 2 to 10% by weight,

Zeolite (preferably clinoptilolite) and / or metakaolin: 2 to 18% by weight,

Quartz sand: 50 to 85% by weight,

Water retention agent: 0.01 to 0.5% by weight,

Retarder: 0.01 to 0.5% by weight.

Such a plaster and masonry mortar is suitable for indoor and outdoor use, is water and weather resistant; It meets the minimum requirements of EN 998-1 (plaster mortar) and 998-2 (masonry mortar).

A preferred adhesive and reinforcing mortar for thermal insulation composite systems (ETICS) comprises:

Alpha-calcium sulfate hemihydrate: 15 to 30% by weight,

Portland cement CEM I: 2 to 10% by weight,

Zeolite (preferably clinoptilolite) and / or metakaolin: 2 to 15% by weight,

Quartz sand: 40 to 70% by weight,

Limestone flour (d50 preferably 5 to 15 μηη): 2 to 10 wt .-%,

Water-retaining agent: 0.1 to 1% by weight,

Fibers: 0 to 0.5% by weight,

Redispersible polymer powder (in particular vinyl acetate-ethylene copolymer-based): 0, 1 to 3% by weight,

Hydrophobing agent: 0 to 1% by weight,

Retarder: 0 to 0.8% by weight.

A preferred screed mortar, especially suitable for areas with

Moisture (e.g., bathrooms, basements) includes:

Alpha-calcium sulfate hemihydrate: 10 to 20% by weight,

Portland cement CEM I: 2 to 5% by weight,

Zeolite (preferably clinoptilolite) and / or metakaolin: 1 to 7% by weight,

Calcium aluminate cement (in particular alumina cement (preferably with Al 2 O ₃ about 40% by weight)): 1 to 5% by weight,

Quartz sand: 10 to 30% by weight,

Coarse quartz sand / gravel (grain size preferably 0.2-4 mm): 45 to 75% by weight, Liquefier: 0 to 0.3% by weight,

Retarder: 0 to 0.4% by weight.

Alternatively, based on the screed mortar, it is also possible to formulate a screed binder which is obtained by omitting the coarse quartz sand / gravel. In this case, the sand / gravel is then immediately on the construction site,

or, in the case of screeds from the truck mixer, added in the mixer.

A preferred self-leveling floor leveling compound comprises:

Alpha-calcium sulfate hemihydrate: 15 to 40% by weight,

Portland cement CEM I: 2 to 10% by weight,

Zeolite (preferably clinoptilolite) and / or metakaolin: 2 to 10% by weight,

Calcium aluminate cement (in particular alumina cement (preferably with Al 2 O ₃ about 40% by weight)): 1 to 7% by weight,

Limestone flour: 10 to 40% by weight,

Quartz sand: 30 to 70% by weight,

Liquefier: 0.01 to 2% by weight,

Water retention agent (in particular hydroxyethyl cellulose): 0.02 to 0.5% by weight,

Retarder: 0 to 1% by weight.

The building chemicals tile adhesive, grout, plaster and masonry mortar, adhesive and reinforcing mortar, screed, self-leveling floor leveling compound, meet each of the standardized minimum requirements for the respective products, sometimes even the increased requirements, namely:

- tile adhesive: increased requirement of class C2F according to EN 12004: 2007,

- grout: increased requirement of class CG2A according to EN 13888: 2009,

- masonry mortar: strength classes M1 to M10 according to EN 998-2: 2010,

- self-leveling floor leveling compound: strength classes> C25 F6 according to EN 13813: 2002,

- Adhesive and reinforcing mortar: fulfills the required adhesive tensile strength for

Substrate and insulating material, even after storage in accordance with ETAG 004,

EN13499.

- Screed: Strength classes> C25 F5 according to EN13813: 2002. Examples:

A) Binder compositions

By mixing the ingredients listed in Table 1, the comparative compositions V1 to V2 and the inventive compositions B1 to B6 were prepared.

Table 1 :

a-HH: a-CaSO ₄ .5 H ₂ O

CEM I 52.5 R: Portland cement

Secar 51: calcium aluminate cement

The binder compositions were further processed into mortar compositions (see B) below) and tile adhesives (see C) below) and tested for essential properties.

B) mortar compounds

The comparative compositions V1 to V2 and the invention

Compositions B1 to B6 were each mixed in a weight ratio of 1: 2 with quartz sand H33. This resulted in the comparative mortar masses VM1 to VM2 and the mortar masses BM1 to BM6 according to the invention.

These were each mixed with water in a weight ratio of 4: 1 (4 parts of composition per 1 part of water) and from the resulting processing finished mortar compounds as described in the standard EN 196-1 described prism-shaped specimens measuring 4 x 4 x 16 cm. The test specimens were disconnected after 24 h and examined for bending tensile strength and compressive strength. The determination of flexural tensile strength and compressive strength after water storage was carried out according to EN 196-1. For this purpose, the prisms were stored directly after demolding under water and bending tensile strength and compressive strength in each case after 6 days, 27 days and 55 days of storage in water, ie after a total storage time of 7 days, 28 days or 56 days determined. In addition, flexural strength and compressive strength after dry storage (7 days, 28 days and 56 days storage at 23 ° C and 50% relative humidity (RH)) were determined, measurements being performed according to EN 196-1. The results are summarized in Table 2, where all values are given in N / mm ² .

Table 2:

BZF: bending tensile strength

DF: compressive strength

^* : Test piece torn; no determination possible

It has been found that mortar compositions based on binder compositions according to the invention have good flexural tensile strengths after dry storage and Have compressive strengths. In water storage, flexural tensile strengths and compressive strengths are achieved, which are superior to those of mortar compositions whose binder is based purely on a-CaS0 ₄ .5 H ₂ 0, are superior. The mortar compositions according to the invention are therefore characterized by an increased long-term stability under moisture stress.

C) tile adhesive

The comparative composition V2 and the inventive compositions B1 to B6 were further processed into tile adhesives. For this purpose, in each case 46% by weight of a binder composition comprising 51.9% by weight of quartz sand having a grain size of 0.1-0.5 mm, 0.5% by weight of methylcellulose, 1.5% by weight of a redispersible polymer powder were applied Vinyl acetate / ethylene base and 0.1 wt .-% retarder (Ca salt of an N-polyoxymethylene amino acid) mixed together. This resulted in the comparison tile adhesive VF2 and the tile adhesives BF1 to BF6 according to the invention.

These were each mixed with water in a weight ratio of 3: 1 (3 parts of composition per 1 part of water) and the resulting ready-to-use tile adhesives were examined for their adhesion values.

Adhesive tensile strength values were determined according to test methods EN 1348: 2007, 8.2 after dry storage (measured after 28 days and 56 days), and according to

Test method EN 1348: 2007, 8.3 after water storage (measured after 28 days and 56 days, the storage being carried out first for 7 days at 23 ° C and 50% rh and then for 21 or 49 days under water).

The results are summarized in Table 3, where all values are given in N / mm ² . Table 3:

It can be seen that tile adhesives based on a binder mixture without the addition of zeolite and optionally metakaolin are clearly superior in terms of stability under the influence of moisture on the basis of the binder compositions according to the invention.

D) Influence of the amount of calcium aluminate cement on the drying properties of tile adhesives

By mixing the ingredients, a base composition of 35 parts by weight of a-CaS0 ₄ .5 H ₂ O, 6.4 parts by weight of CEM I 52.5 R (Portland cement), 4.6 parts by weight of metakaolin, 0 , 5 parts by weight of methylcellulose, 1, 5 parts by weight of a redispersible polymer powder based on vinyl acetate / ethylene and 0.1 parts by weight of retarder (Ca salt of an N-polyoxymethylene amino acid).

By mixing in each case 48.1% by weight of this base composition with increasing amounts of Secar 51 (calcium aluminate cement) (0, 1, 2, 3, 4, 5 or 6% by weight) and quartz sand having a grain size of 0.1 -0.5 mm in each case to 100% by weight missing amount, the tile adhesive VF3 (comparison) and BF7 to BF12 were obtained and determined their residual water content by the Darr test method.

For this purpose, the tile adhesives to be examined were each mixed with 25% by weight of water to give a processing consistency, from which disc-shaped mortar cakes with a diameter of 100 mm and a thickness of 10 mm were obtained formed, which were immediately transferred into each a water vapor-tight HDPE bag. The bags were sealed so that no water vapor could escape. After storage of the bags at 23 ° C for 1, 3, 7 or 28 days of each bag was opened and weighed the cured mortar cake and then dried in a ventilated oven at 40 ° C for 24 hours. After 24 hours, the dried mortar cake was weighed again and the weight difference in% was calculated. This difference corresponds to the residual water content, ie the free non-crystalline water.

The results are summarized in Table 4, with all values given in weight percent.

Table 4:

RWG: residual water content

The results show that the residual water content decreases with increasing amount of Caiciumaluminatzement in the tile adhesive, ie its drying properties are better. A significant jump is in increasing the amount of Caiciumaluminatzement of 2 wt .-% to 3 wt .-%, corresponding to 4.2 wt .-% to 6, 1 wt .-% based on the binder composition (o CaSCyO.5 H ₂ O, Portland cement, metakaolin and Caiciumaluminatzement) to determine.

Claims

claims

1. binder composition,

full

(a) calcium sulphate,

(b) Portland cement,

(c) calcium aluminate cement,

(d) zeolite and / or metakaolin,

2. Composition according to claim 1, characterized in that the

Calcium sulfate is selected from anhydrite, calcium sulfate hemihydrate and mixtures thereof.

3. The composition according to claim 1, characterized in that it is the calcium sulfate to alpha-calcium sulfate hemihydrate.

4. The composition according to claim 1, characterized in that it is anhydrite in the calcium sulfate and the composition contains an additional sulfate salt.

5. The composition according to at least one of claims 1 to 4, characterized in that the calcium sulfate in an amount of 60 to 98 parts by weight, preferably 60 to 97.9 parts by weight, in particular 60 to 89 parts by weight, more preferably 60 to 75 parts by weight and most preferably 60 to 74 parts by weight, based on a total amount of 100 parts by weight, which is formed from the four components (a) calcium sulfate, (b) Portland cement , (c) calcium aluminate cement, (d) zeolite and / or metakaolin.

6. The composition according to at least one of claims 1 to 5, characterized in that the Portland cement in a total amount of 1 to 45 parts by weight, preferably 5 to 30 parts by weight, in particular 8 to 20 parts by weight, particularly preferably 10 to 20 parts by weight and very particularly preferably 1 to 20 parts by weight, based on a total amount of 100 parts by weight, formed from the four components (a) calcium sulfate, (b) Portland cement, (c) calcium aluminate cement, (d) zeolite and / or metakaolin.

7. The composition according to at least one of claims 1 to 6, characterized in that zeolite and / or metakaolin in a total amount of 1 to 30 parts by weight, preferably 5 to 25 parts by weight, in particular 8 to 20 parts by weight , particularly preferably 10 to 20 parts by weight, based on a total amount of 100 parts by weight, formed from the four components (a) calcium sulfate, (b) Portland cement, (c) calcium aluminate cement, (d) zeolite and / or metakaolin.

8. The composition according to at least one of claims 1 to 7, characterized in that the calcium aluminate cement in an amount of> 0, 1 parts by weight, preferably in an amount of 1 to 45 parts by weight, more preferably 1 to 30 wt .- Parts, in particular 1, 5 to 20 parts by weight, more preferably 2 to 12 parts by weight and most preferably 5 to 12 parts by weight, based on a total amount of 100 parts by weight, formed of the four components (a) calcium sulfate, (b) Portland cement, (c) calcium aluminate cement, (d) zeolite and / or metakaolin.

9. The composition according to at least one of claims 1 to 8, characterized in that the Calciumaluminatzement is selected from

Alumina cement, calcium sulfoaluminate cement and mixtures thereof.

10. Construction product comprising 1 to 90 wt .-%, preferably 10-70 wt .-%, in particular 20-55 wt .-% of a binder composition according to at least one of claims 1 to 9.

1 1. construction product according to claim 10, characterized in that the construction chemical product is selected from tile adhesives, grout,

Plaster mortars, masonry mortars, screed mortars, repair mortars, anchor mortars, adhesive and reinforcing mortars for thermal insulation composite systems, self-leveling floor leveling compounds, wall and floor leveling compounds, and

Sealing slurries.

12. A method of using a water-treated composition according to any one of claims 1 to 9 or a mixed with water construction chemical A product according to any one of claims 10 to 11 as a binder between at least two articles comprising applying and hardening the

Composition or of the construction chemical product to form a water-resistant bond between the articles.

A method of using a water-borne composition according to any one of claims 1 to 9 or a water-borne chemical composition according to any one of claims 10 to 11 comprising applying and hardening the water-borne composition to form a water-resistant outer surface.