HK1125961B - Preparation containing organosilicium compound and its use - Google Patents

Description

Mixtures containing organosilicon compounds and their use

Technical Field

The invention relates to the use of mixtures based on at least one water-soluble organic polymer and an organosilicon compound for protecting substrates against corrosion, to mixtures based on at least one water-soluble organic polymer and an organosilicon compound, and to a method for producing said mixtures.

Background

In chemistry, corrosion refers to a chemical reaction of a material with its surrounding substances, wherein a measurable change is produced in the material. Typically, the material is a metal. The term may also be used for other materials such as glass, cement, mortar and other inorganic building materials. In addition, there are various types of corrosion, for example oxygen corrosion, which forms oxide layers such as rust, hydrogen corrosion, also known as acid corrosion, hydrogen embrittlement, glass corrosion, in which the surface of glass cups and other glass articles is structurally altered and no longer removable opalescent cloudiness can be recognized visually, and bacterial anaerobic corrosion.

To suppress these phenomena, a large number of various corrosion inhibitors are available, which are particularly recommended for protecting steel in concrete materials. Some are also powdered and can be added in this form or in solution.

Aromatic sulfonic acid compounds and their metal salts are described, for example, in EP1176125A1 for use in concrete and in particular in repair mortars.

GB1153178 describes compositions of water-soluble chromates, nitrates or nitrites with salts selected from aromatic or heterocyclic amines, which are used as corrosion inhibitors in concrete materials. The disadvantage is, in particular, that, when the chloride content in the concrete is high, relatively high amounts of nitrites or nitrates have to be incorporated to increase the efficiency. Further, it is also disadvantageous that the active ingredient is gradually consumed by the decomposition reaction.

In addition, JP6345512 describes the use of metal powders such as Zn, Al, Mg as corrosion inhibitors in concrete or polymer modified concrete.

All these products, although suitable as corrosion inhibitors for protecting steel in concrete materials, have no or no substantial effect on the water repellency of these building materials.

To meet this requirement, US20040103814a1 uses a mixture of a hydrophobizing agent, one or more alkanolamines and optionally a corrosion inhibitor, wherein special requirements are made of the hydrophobizing agent. However, this system is liquid and therefore cannot be added to a dry mortar mixture in powder form. In addition, it is also necessary to add hydrophobicizing agents and corrosion inhibitors, which exert two effects in the mortar.

Silanes and siloxanes have been known for decades as hydrophobizing agents. They are generally available only as liquids and applied to the cured concrete as a treatment. Since these agents are applied primarily by spraying, a plurality of application steps are usually additionally required in order to achieve the desired product consumption, i.e. the desired degree of application. This is not only very time consuming but also depends to a large extent on weather conditions, for example it cannot be rain or wind gusts. In order to be able to apply larger quantities, so-called "pastes" have also been developed. In general, however, they lead to a deterioration in the penetration of the material into the substrate, which is a negative effect particularly on high-density substrates such as concrete. In addition, for higher oligomeric materials, discoloration of the substrate surface or at least an undesirable glossy or oily appearance, which is caused by the inability of the higher oligomers to penetrate into the substrate, can also occur.

In addition, in the protection of concrete, in particular for reinforced concrete and for reinforcing steel reinforcements, it is also required that the frozen salt or chloride-containing marine environment is not only hydrophobicized, since the corrosive metals in the building are rather detrimental to the load-bearing capacity of the building.

EP1205481a2 discloses mixtures of n-propyl ethoxysiloxanes and emulsions thereof for impregnating inorganic substrate surfaces. These mixtures are applied to the cured surface in liquid form, and multiple applications are often necessary or at least beneficial.

EP1308428a2 describes the use of liquid silanes or silane formulations as corrosion inhibitors, in which they are essentially applied to the surface of a cured substrate. There is no description of silanes and silane preparations in powder form.

EP0913370a1 discloses a method for producing homogeneous and hydrophobic concrete, the so-called hydrophobicizing of materials, in which the absorption of NaCl solution can also be significantly reduced. To this end, an aqueous emulsion containing hydrolyzable organosilicon compounds is added thereto, and the emulsion contains at least one alkoxysilane and optionally an organosilicon compound as surfactant. The system is liquid and cannot be converted without difficulty into powder form, which increases its difficulty of storage and transport, especially at temperatures below freezing. In addition, it is also not possible to produce dry mortars and/or powdered compounds for the preparation of concrete containing these systems.

EP0228657a2 teaches, inter alia, water-free powders which are redispersible in water or soluble in water, are based on at least one organosilicon compound and are used as additives in mortars, hydraulic binders, clays or colored coatings, in water-soluble form for hydrophobicizing bulk materials or as binders for fine-grained inorganic or organic materials. There is no mention of the use of such powders for hydrophobicizing and/or protecting cement systems, in particular metals coated with inorganic building materials, against corrosion. In addition, these powders cannot be prepared without problems, which increases the difficulty of their production, storage and use.

EP0811584a1 describes cementitious materials in powder form which comprise a granulated hydrophobicizing additive and which contain 5 to 15% by weight of an organopolysiloxane component, 10 to 40% by weight of a water-soluble or water-dispersible binder and 50 to 80% by weight of carrier particles. The cementitious material acts as a hydrophobic material. There is no mention that these products are useful for protection against corrosion. Furthermore, it is disadvantageous that organopolysiloxanes which are primarily responsible for the hydrophobic effect can be present in the additive only in small amounts. Accordingly, the amount must also be correspondingly large, which in turn leads to disadvantageous effects due to other constituents, such as cement and carrier particles.

Unfortunately, all these measures are not sufficient for building modification and maintenance and therefore do not meet the high demands. In particular, the surface treatment or hydrophobization of stone or building materials with the formulations and measures known hitherto cannot be sufficiently effective for reducing the corrosion of materials, in particular steel reinforcement. In addition to stress cracking, it is known that, above all, the building material is cracked or embrittled, in particular due to environmental and climatic influences, as a result of which substances penetrating into the building body can further damage the building.

The object of the present invention is therefore to provide a material for protecting materials against corrosion, which can be added to dry preparations, in particular in powder form, but can also be used in liquid preparations. The key point is that the powder is easy to prepare and stable to store. If added to a dry formulation, they should wet well and the material should disperse, redisperse or dissolve well to ensure rapid and optimal distribution. The key point is also that the material should be able to fully perform its function in a matrix stirred with water. In addition, it should be nontoxic and not interact with the hydraulic binding constituents or only to a small extent, so that problems such as delayed binding of the inorganic binding constituents do not occur.

Disclosure of Invention

This complex task can surprisingly be solved by protecting the substrate from corrosion by using:

a mixture which can be dispersed, redispersed or dissolved in water (also referred to below simply as powder) based on at least one organic polymer dissolved in water and at least one organosilicon compound,

or a composition comprising at least one water-soluble organic polymer, at least one organosilicon compound and water. According to the invention, this object is advantageously achieved according to the measures described in the claims.

The invention therefore consists in protecting a substrate against corrosion using at least one dispersible, redispersible or water-soluble mixture based on at least:

(i) at least one organic polymer soluble in water, and

(ii) at least one organic silicon compound,

wherein the organosilicon compound is selected from the group consisting of organofunctional silanes, polysilanes, silane esters, siloxanes, silicones, and/or silicates.

The mixtures according to the invention or the mixtures used according to the invention are preferably based on at least one component (i) from the series of substances mentioned by way of example only, selected from polyvinyl acetate, polyvinyl alcohol, polyvinylpyrrolidone, starch derivatives, polyacrylates, polymethyl acrylates, polymaleates, cellulose ethers soluble in water, polyethylene oxides soluble in water, proteins soluble in water. However, it is also possible to use other water-soluble polymers as component (i). Here and below, the respective disclosure in the present application with regard to component (i) can also be listed in component (iii) and vice versa, respectively.

A large number of organosilicon compounds can be used as component (ii), where "organofunctional" is synonymous with "organic" in the context of the present invention, i.e. means that the silicon compounds have at least one substituent having at least one carbon atom. Preferred organosilicon compounds are selected from the group consisting of organofunctional silanes, polysilanes, silane esters, siloxanes, silicones and/or silicates. In particular, the organosilicon compounds can be used as individual components, as a mixture of at least two organofunctional silanes, as a mixture of at least two organofunctional siloxanes or as a mixture of, for example, at least one organofunctional silane and at least one organofunctional siloxane. The respective disclosure of component (ii) here and in the following application is also included in component (iv), and vice versa accordingly.

It is generally preferred, but not necessary, that the organosilicon compounds be present in liquid form and that the boiling point of the organosilicon compounds used at atmospheric pressure not be too low, preferably about 100 ℃ or higher. They may be soluble, insoluble or only partially soluble in water. Compounds which have no OR only limited water solubility, for example of the formula Si (OR')₄Of the formula R₃Si(SiR₂)_nSiR₃And wherein n-0 to 500 and preferably n-0 to 8Polysilanes of the formula or the general formula R_cH_dSi(OR’)_e(OH)_fO_{(4-c-d-e-f)/2}And wherein c is 0 to 3, d is 0 to 2, e is 0 to 3, f is 0 to 3 and the sum of c + d + e + f is at most 3.5, or mixtures thereof, wherein each R' independently represents an alkyl or alkoxyalkylene group having 1 to 4C atoms and is preferably methyl or ethyl, the radicals R are identical or different and are branched or unbranched alkyl groups having 1 to 22C atoms, cycloalkyl groups having 3 to 10C atoms, alkylene groups having 2 to 4C atoms, aryl, aralkyl, alkaryl groups having 6 to 18C atoms, and wherein said group R may also be substituted by halogens such as F OR Cl, by ether, thioether, ester, amide, nitrile, hydroxyl, amine, carboxyl, sulfonic, epoxy, carboxylic anhydride and carbonyl groups, and in the case of polysilanes R may also represent OR'.

Preferred organosilicon compounds of (ii) are in particular those of the general formula (R ') Si (OR')_xO_yAnd wherein 0< x <2, 0.5< y < 1.5, preferably 1.0< x <2.0 and 0.5< y ≦ 1.0 and with the proviso that (2y + x) ≦ 3, wherein the radicals R "are identical or different and R" is a linear, branched or cyclic alkyl radical having 1 to 18C atoms, furthermore the radicals R '"are identical or different and R'" represents hydrogen or a linear or branched alkyl radical having 1 to 4C atoms, preferably H, methyl, ethyl, propyl.

Furthermore, the organosilicon compounds (ii) are preferably tetraalkoxysilanes, alkyltrialkoxysilanes, dialkyldialkoxysilanes, where the alkyl group can be a linear and/or branched C₁-to C₂₀Alkyl, and as alkoxy there may be straight-chain and/or branched C₁To C₁₀Alkoxy, and as the latter preferably methoxy, ethoxy and/or isopropoxy are used. In addition, if an alkyl group is not used, a copolymerizable alkylene group such as vinyl, allyl and/or (meth) acryloyl may also be used.

Non-limiting examples of preferred organosilicon compounds within the scope of the present invention are organofunctional silanes or siloxanes selected from the following series:

alkoxysilanes such as hydrogentrimethoxysilane, hydrogentriethoxysilane, tetramethoxysilicon, tetraethoxysilicon,

alkylsilanes such as methyltrimethoxysilane, methyltriethoxysilane, methyltripropoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, n-and isopropyltrimethoxysilane, n-and isopropyltriethoxysilane, n-and isobutyltrimethoxysilane, n-and isobutyltriethoxysilane, n-and isopentyltrimethoxysilane, n-and isopentyltriethoxysilane, n-and isohexyltrimethoxysilane, n-and isooctyltrimethoxysilane, n-and isooctyltriethoxysilane, hexadecyltrimethoxysilane, hexadecyltriethoxysilane, octadecyltrimethoxysilane, octadecyltriethoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, n-and isobutylmethyldimethoxysilane, n-and isobutylmethyldiethoxysilane, cyclohexylmethyldimethoxysilane, diisopropyldimethoxysilane, diisobutyldimethoxysilane and isobutylisopropyldimethoxysilane,

vinylsilanes, such as vinyltrimethoxysilane, vinyltriethoxysilane, vinylmethyldialkoxysilane and vinyltris- (2-methoxyethoxysilane),

aminoalkoxysilanes, e.g. 1-aminomethyltrimethoxysilane, 1-aminomethyltriethoxysilane, 2-aminoethyltrimethoxysilane, 2-aminoethyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-aminoisobutyltrimethoxysilane, 3-aminoisobutyltriethoxysilane, N- (N-butyl) -3-aminopropyltrimethoxysilane, 3-aminopropylmethyldiethoxysilane, 3-uretyl-propyltrimethoxysilane, 3-uretyl-propyltriethoxysilane, N-aminoethyl-3-aminopropyltrimethoxysilane, N-aminoethyl-3-aminopropyltriethoxysilane, N-aminoethyltrimethoxysilane, Triamino-functional propyltrimethoxysilyl and 3- (4, 5-dihydroimidazolyl) propyltriethoxysilane,

glycidyl ether or glycidyl alkyl functionalized alkoxysilanes such as 3-glycidoxypropyltrimethoxysilane and 3-glycidoxypropyltriethoxysilane,

chloro-and fluoroalkyl-functional alkoxysilanes, such as tridecafluorooctyltriethoxysilane and tridecafluorooctyltrimethoxysilane, 3-chloropropyltriethoxysilane,

acryloyl-or methacryloyl-functional alkoxysilanes, such as acryloyloxypropyltrimethoxysilane, acryloyloxypropyltriethoxysilane, 3-methacryloyloxypropyltrimethoxysilane, 3-methacryloyloxypropyltriethoxysilane, 3-methacryloyloxyisobutyltrimethoxysilane, 3-methacryloyloxyisobutyltriethoxysilane, 3-methacryloyloxy-2-methylpropyltrimethoxysilane and 3-methacryloyloxy-2-methylpropyltriethoxysilane,

mercapto-functional alkoxysilanes such as 3-mercaptopropyltrimethoxysilane and 3-mercaptopropyltriethoxysilane,

sulfane-or polysulfane-functionalized alkoxysilanes, such as bis- (triethoxysilylpropyl) -tetrasulfane, bis- (trimethoxysilylpropyl) -tetrasulfane, bis- (triethoxysilylpropyl) -disulfane, bis- (trimethoxysilylpropyl) -disulfane, bis- (triethoxysilylpropyl) -sulfane, bis- (trimethoxysilylpropyl) -sulfane, bis- (triethoxysilylpropyl) -pentasulfane and bis- (trimethoxysilylpropyl) -pentasulfane,

wherein the corresponding oligomer formed by hydrolysis in the aforementioned monomeric organosilane may be present in a concentration of 0.001 to 5% relative to the composition,

other organosilicon compounds, e.g. beta-nitrilotriethoxymethylSilanes, aryl silanes, in particular phenyltriethoxysilane, but also dipropyldiethoxysilane, triphenylsilanol and their preferably liquid condensation products, silanes containing quaternary ammonium groups, in particular amino-functional silanes or siloxanes, carboxylic acid-and carboxylic acid anhydride-functional silanes, disilanes, such as dimethyltetraalkoxysilane, tetramethyldialkoxydisilane, trimethyltrialkoxydisilane or their (co) condensates, which are usually obtained from the corresponding chlorides. Preference is also given to methylhydrogenpolysiloxanes terminated by trimethylsilyloxy groups, mixed polymers which are terminated by trimethylsilyloxy groups and which consist of dimethylsiloxane units and methylhydrogensiloxane units and dimethylpolysiloxanes which each have a hydroxyl group bonded to Si in the terminal units, and also organofunctional siloxanes, such as vinyl-functional siloxanes, alkyl-functional siloxanes, vinyl/alkyl-functional siloxanes (cocondensates), methacryloyl-functional siloxanes, amino-functional siloxanes, aminoalkyl/alkyl-functional siloxanes, aminoalkyl/fluoroalkyl-functional siloxanes or corresponding cocondensates and condensates, for example but not exclusively from EP0590270A, EP0716127A, EP0716128A, EP0748357A, EP0760372A, EP0814110A, EP0879842A, EP0846715, EP0930342A, EP1101787A, EP1205481A, EP1304345A, EP 11028, Those of WO06/081891, WO06/081892, WO06/010666, DE19823390A, DE19834990A, DE19849308A, DE19904132A, DE19908636A and DE10056344A, or oligomeric silicates, for exampleOr those disclosed in DE2744726C and DE2809871C, including hydrogenated cyclosiloxanes, e.g. the so-called D of low degree of polymerization n-2 to 20, in particular n-4 to 6_nAnd (D) a compound of (H).

However, the organosilicon compounds can also be prepared, for example, by the methods described in Noll, Chemie und Technologie der Silicone, second edition, 1968, Weinheim und Houben-Weyl, method der organischen Chemie, volume E20, pages 1782 and 2219, Georg Thieme Verlag, Stuttgart, 1987.

According to the invention, the mixtures according to the invention can be added in a simple and economical manner during the production of inorganic building materials. In particular, the mixtures or powders according to the invention can preferably be added or mixed in at the point of the formulation of the building materials from the individual components or additives or of ready-to-use building material mixtures, that is to say directly at the point of the subsequent processing of the building materials to be processed, or in the preparation of ready-to-use powdered building material mixtures, for example concrete, mortar or mortar mixtures, or in the preparation of ready-to-use powdered additives for use in building materials such as concrete, lime, sand or rheology assistants.

According to the invention, the mixtures according to the invention are used to protect substrates, in particular metals and/or natural and/or man-made inorganic building materials, against corrosion. Preferred metals are iron and iron alloys, in particular steel and aluminum alloys. Metals are typically encapsulated by inorganic building materials, such as steel reinforcements in concrete. Preferred building materials are mortar, concrete, mortar, joint compound, brick material, masonry, building stone, building elements and/or natural stone such as limestone sand.

The mixtures according to the invention are preferably used in and/or on inorganic building materials and are intended to be in contact with, wrap around or surround metals. Particularly preferred inorganic building materials are, for example, concrete, in particular reinforced concrete, expansive cement, gas-hardening cement, foamed cement, shaped building elements made of cement, mortar, joint material, building elements made of lime sand stone, clinker, brick, porous tile and tile, ceramic tile, natural stone, fiber cement, seamless floors, clay products, walls, facades, roofs and buildings, such as bridges, harbour buildings, residential buildings, factory buildings and public buildings, such as parking houses, railway stations or schools, but also shaped products, such as sleepers or L-stones.

Artificially manufactured inorganic building materials generally contain an inorganic binding agent which uses at least a) a hydraulic binding agent, in particular cement, b) a latent hydraulic binding agent, in particular acidic blast furnace slag, pozzolan and/or metakaolin, and/or c) a non-hydraulic binding agent which reacts under the influence of air and water, in particular calcium hydroxide and/or calcium oxide.

Preferred as hydraulic binders are cements, in particular portland cements, such as calcium sulfate in the form of alpha and/or beta hemihydrate and/or anhydrite, as described in EN196 CEM I, II, III, IV and V, and/or clay melt cements. As latent hydraulic binders, pozzolans, such as metakaolin, calcium metasilicate and/or vulcanized slag, vulcanized tuff, volcanic soil, fly ash, blast furnace slag and/or silica dust, which react hydraulically with a calcium source, such as calcium hydroxide and/or cement, can be used. As non-hydraulic binders which react under the influence of air and water, lime can be used in particular, in most cases in the form of calcium hydroxide and/or calcium oxide. Most preferably a pure portland cement based system or a mixture of portland cement, clay melt cement and calcium sulfate, in both systems optionally also a latent hydraulic and/or non-hydraulic binder can be added.

In general, cements or cement compositions that are capable of producing higher pH values with water are preferred. The function of which is that the organosilicon compound is capable of bonding to the metal having an oxidation passivation layer on its surface when in contact therewith.

Inorganic binders are generally mixed with some dopant, sometimes also referred to as filler. Typical dopants are quartziferous and/or carbonaceous sands and/or powders such as quartzite and/or limestone powder, carbonates, silicates, chalk, layered silicates and/or precipitated silicic acid. In addition, light fillers, such as glass microspheres, polymers such as polystyrene spheres, aluminosilicates, silicon oxide, aluminum silicon oxide, calcium silicate hydrate, aluminum silicate, magnesium silicate, aluminum silicate hydrate, calcium aluminum silicate, calcium silicate hydrate, silicon dioxide and/or aluminum-iron-magnesium silicate, can also be used, but clays such as bentonite can also be used, and the fillers and/or light fillers mentioned can also have natural or artificially generated colors.

If silane products which have a hydrophobicizing action are used as organosilicon compounds, the corrosion resistance of building materials and structures which have been modified in this way, in contrast to the corrosion protection measures customary in the market, with corresponding steel or metal reinforcing bars, can be significantly improved by the hydrophobicizing effect achieved.

It has also surprisingly been found that, in addition to the use according to the invention as corrosion inhibitor, the mixtures can also be used for the reinforcement of stone materials, and that the hydrophobic properties and effects are retained without impairment.

It is particularly surprising that, in addition to the hydrophobic and/or stone-reinforcing effect of the formulations containing organofunctional silanes and/or organofunctional siloxanes, when the aforementioned powders are used in repair materials or in materials for the manufacture of building stones, building parts or buildings, it is also advantageously possible to simultaneously obtain a corrosion-retarding effect, in particular with respect to corrosion of metals or of cement produced when in contact with water and salts. Thus, the use of the invention also preferably includes the simultaneous prevention of corrosion of metal and stone.

Furthermore, when the powders according to the invention are applied to these materials, good and particularly uniform reinforcing properties of the stone material can be established also in the building at a later date. The hydrophobic properties and effects can also be kept intact.

In addition, it is also preferred in the field of construction to use the powders or mixtures detailed above according to the invention for the preparation of inorganic materials suitable for repair purposes. By using this, the process of corrosion can also be slowed down significantly, at least in time.

The corrosion protection effect according to the invention is achieved when the corrosion rate is reduced by more than about 50%, preferably more than about 80%, in particular more than about 90%, compared to the unprotected material. For the case of steel reinforcement, the corrosion rate can be determined, for example, by the observed corrosion current relative to the corresponding unprotected concrete.

The amount of the mixture of the invention in the concrete may be up to about 5% by weight or more based on the solids content of the mixture and the cement content of the concrete, taking care to comply with possible specifications. The amount is preferably adjusted so that the optimum corrosion protection for the use according to the invention is obtained. Thus, higher amounts of organosilicon compound active ingredient can be used without substantial effect on other concrete properties, while also allowing for problem-free adherence to building codes.

The amount of the mixture according to the invention in the mortar is about 0.01 to about 10% by weight, based on the solids content of the mixture and the dry matter content of the mortar, and higher contents may also be used for special applications. Preferably, about 0.05 to about 5% by weight, in particular about 0.1 to 3% by weight, of the mixture is used.

The mixtures according to the invention, which surprisingly function well as corrosion inhibitors, are generally incorporated into hydraulic binders and can also be added together with other constituents in the production of mineral building materials.

The mixtures of the invention are generally present in powder form. They can therefore be processed in a particularly simple and economical manner to give the corresponding dry mortars, dry mortars and/or dry premixes for concretes, such as cements, in particular modified cements. This enables particularly good charging and a very homogeneous dispersion of the mixture in the subsequent building materials and thus also in the subsequently produced building stones, building components and correspondingly the buildings obtained therefrom. These dry mixtures can then be simply mixed in situ by adding a specific amount of water and then processed.

However, it is also possible to mix the mixtures according to the invention as separate components during the production of the building materials. In this embodiment, the building material components are preferably mixed or kneaded with the required amount of water, wherein the mixture is added directly before, during and/or after the addition of water. However, it is also possible to add the mixture first to the stirred water and in this way to the dry or already moist material in the mixer.

The mixtures can also be dissolved and are preferably applied in the form of low to high viscosity, i.e. pastes, as surface protection agents, for example by spraying, brushing, rolling or knife coating, onto the resulting building materials. In this case, the composition or preparation may be in excess of 50g/m²Preferably more than 100g/m²Particularly preferably more than 200g/m²Is applied to the surface of the substrate. In some cases, in particular when the desired amount of active ingredient cannot be applied in one process step because the substrate has only a low adsorption capacity, it is also possible to use multiple coating processes, the drying time of which is, for example, from 2 hours to about 2 days between the process steps. If the mixture is used in the form of a powder, it is preferred for such applications that the powder is pre-dispersed, redispersed or dissolved in water; however, other liquids that evaporate at ambient temperature may also be used for this purpose.

The invention also relates to a mixture which can be dispersed, redispersed or dissolved in water, based on:

(iii) at least one organic polymer soluble in water, and

(iv) at least one organosilicon compound containing at least one Si-O-Si and/or at least one Si-Si bond,

wherein the content of organic polymer (iii), based on organic polymer (iii) and organosilicon compound (iv) and the total amount, is between about 40 and about 80% by weight, preferably 40 to about 70% by weight, particularly preferably 45 to 60% by weight, and wherein the organosilicon compound having at least one Si-O-Si bond is based on an oligomer mixture of alkylalkoxysiloxanes which contains from 50 to 100% by weight of alkylalkoxysiloxanes and which has a degree of oligomerization of from 2 to 20, and the organosilicon compound having at least one Si-Si bond is a polysilane.

As the organic polymer of the component (iii), those disclosed above as the organic polymer of the component (i) or those based thereon can be preferably used.

It is likewise possible to use preferably those of component (ii) disclosed above as organosilicon compounds having at least one Si-O-Si bond of (iv), in particular organosiloxanes such as alkylalkoxysiloxanes or alkylalkoxysiloxane mixtures and/or oligomeric silicates. In addition, as the organosilicon compound of (iv) having at least one Si-Si bond, use may also be made of one or more polysilanes. Mixtures of different organosilicon compounds may also be used.

As the organosilicon compounds, use may preferably be made of those of the above-disclosed components (ii) or (iv), in particular of organosiloxanes such as alkylalkoxysiloxanes or alkylalkoxysiloxane mixtures, or as starting materials in the preparation of the mixtures or powders according to the invention.

Thus, for the mixtures of the invention and for the mixtures suitable for the application of the invention, it is generally preferred that the organosilicon compounds are liquid at room temperature and pressure. It is particularly preferred for the powders of the invention that the organosilicon compounds have a boiling point at atmospheric pressure of about 100 ℃ or more, preferably about 125 ℃ or more, particularly preferably about 150 ℃ or more.

If the organosilicon compound is a liquid at room temperature and pressure, it may be very low or very high depending on the viscosity of the compound. For the mixtures and applications of the invention, however, it is generally preferred to use organosilicon compounds of low viscosity. Preferably, it has a viscosity of about 1 to 1000mPas, more preferably about 2 to 200mPas, in particular about 3 to 50mPas, very particularly preferably about 3 to about 20 mPas. The viscosity is generally measured in accordance with DIN 53015.

Generally, oligomeric silanes or organosiloxanes such as alkylalkoxysiloxanes are characterized by their degree of oligomerization as well as by their structure. This is illustrated in more detail below by the example of n-propyl ethoxysiloxane and mixtures thereof. These organosilicon compounds can be illustrated in detail by the general formula:

the above formula represents a linear n-propyl ethoxysiloxane, and

the above formula represents a cyclic n-propyl ethoxysiloxane,

in the above formula, n represents the degree of oligomerization. That is, the degree of oligomerization reflects the number of Si units per molecule. For determining the degree of oligomerization, Gel Permeation Chromatography (GPC) and²⁹Si-NMR method. When an oligomer mixture is described herein at a level of 100% by weight, based on the well-defined oligomer, then this description takes into account the detection limit (about 1%) of the corresponding oligomer obtained heretofore in the described process. Oligomers having a branched structure but which are difficult to decompose may also be present.

In order to be able to describe said siloxanes in depth, the so-called M-, D-and T-structures are also considered in the present application. A glossary of siloxane structure nomenclature can be found in "The term silicone in Chemielexikon ".

In addition, it is also possible to add the organosiloxanes of components (ii) or (iv), in particular also as oligomeric mixtures of alkylalkoxysiloxanes of the general formula I,

(R”)Si(OR”’)_xO_y (I)

preference is given here to the radicals R "being identical or different and R" being a linear, branched or cyclic alkyl radical having 1 to 18C atoms, preferably methyl, ethyl, propyl, hexyl, octyl, hexadecyl, in particular n-propyl, the radicals R '"being identical or different and R'" representing hydrogen or a linear or branched alkyl radical having 1 to 4C atoms, preferably methyl, propyl, butyl, in particular ethyl, and 1.0< x <2.0 and 0.5< y ≦ 1.0, with the proviso that (2y + x) ≦ 3.

In the context of the present invention, it is particularly preferred to use mixtures of n-propylethoxysiloxanes according to components (ii) or (iv), for example

It is also preferred that the oligomer mixtures used according to the invention contain essentially from 70 to 100% by weight, preferably from about 80 to 99% by weight, particularly preferably from about 90 to 98% by weight, of alkylalkoxysiloxanes having a low degree of polymerization of from 2 to 20, more preferably from 2 to 10 and particularly preferably from 3 to 6. However, these oligomer mixtures may also contain the corresponding monomeric alkylalkoxysilanes.

In particular, the oligomer mixture of components (ii) or (iv) may contain alkylalkoxy siloxanes, in particular n-propylethoxysiloxanes, in amounts which are all made up to 100% by weight by further components, in particular further alkylalkoxy siloxanes, but may optionally also be made up to 5% by weight, preferably to 2% by weight, in particular to 1% by weight, of the balance up to the detection limit, of water and/or alcohol:

from 0 to 30% by weight, particularly preferably less than 10% by weight, very particularly preferably from 0.001 to less than 5% by weight, in particular from 0.01 to less than 1% by weight, of alkylalkoxysiloxanes having a degree of oligomerization n equal to 2 and having M₂In the structure of the utility model, the utility model has the advantages of simple structure,

8 to 40% by weight, particularly preferably 10 to 35% by weight, and very particularly preferably 15 to 30% by weight, of an alkylalkoxy siloxane having M₂D and/or D₃Structures which correspond to the molar mass of alkylalkoxysiloxanes having a degree of oligomerization n of 3,

from 20 to 60% by weight, particularly preferably from 25 to 55% by weight, very particularly preferably from 35 to 50% by weight, in particular from 30 to 45% by weight, of an alkylalkoxy siloxane having M₂D₂And/or M₃T and/or D₄Structures which correspond to the molar mass of alkylalkoxysiloxanes having a degree of oligomerization n of 4,

5 to 35% by weight, particularly preferably 8 to 30% by weight, very particularly preferably 15 to 25% by weight, in particular 10 to 24% by weight, of an alkylalkoxy siloxane having M₂D₃And/or M₃DT and/or D₅Structures, which correspond to the molar mass of alkylalkoxysiloxanes having a degree of oligomerization n of 5,

from 0.1 to 30% by weight, particularly preferably from 0.5 to 25% by weight, very particularly preferably from 5 to 20% by weight, of alkylalkoxy siloxanes having M₂D₄And/or M₃D₂T and/or M₄T₂And/or D₆Structures, wherein the structures are all in accordance with the molar mass of alkylalkoxysiloxanes having a degree of oligomerization n of 6.

Within the scope of component (ii) or (iv) of the present invention, oligomer mixtures containing mixtures of alkylalkoxysiloxanes can be prepared, for example, but not exclusively, according to the teaching of EP1205481a 2. In addition, a composition mentioned therein comprising the additives described therein may also be employed in the present invention. The disclosure of EP1205481a2 is also included within the full scope of the present specification.

Alkylalkoxysiloxanes used according to the invention or for the preparation of powders, e.g.The oligomer mixture of (a) may for example, but not exclusively, have the following physicochemical properties and the following oligomer distribution:

flash point (EN 22719): higher than 70 DEG C

Viscosity (20 ℃, DIN 53015): 35mPas

Density (20 ℃, DIN 51757): 1.04g/cm³

Water content: less than or equal to 0.05 percent

Free alcohol: less than or equal to 0.3 percent

Degree of oligomerization (type of construction)	The proportion is%
		3(M2D，D3)	25
4(M2D2，M3T，D4)	33
		5(M2D3，M3DT，D5)	14
6(M2D4，M3D2T，M4T2，D6)	23

Likewise, the oligomer mixture of the alkylalkoxysiloxanes of components (ii) or (iv) can contain less than 10% by weight, preferably from 0 to 8% by weight, particularly preferably from 0.001 to less than 5% by weight, of alkylalkoxysiloxanes having a degree of oligomerization of more than 6, based on the oligomer mixture.

In addition, the oligomer mixture in the context of components (ii), (iv) or (vi) may also contain from 0 to less than 5% by weight of alkylalkoxysiloxanes having a low degree of polymerization n of from 7 to 20, where the contents are based on the oligomer mixture.

The oligomeric mixtures of alkylalkoxysiloxanes according to component (ii) or (iv) may also suitably contain from 0 to less than 1% by weight of alkylalkoxysiloxanes and they have a low degree of polymerization n of more than 20.

However, the oligomeric mixtures of alkylalkoxysiloxanes for use according to the invention as component (ii) or (iv) contain essentially those alkylalkoxysiloxanes with a degree of oligomerization n equal to 2 to 6, particularly preferably only those alkylalkoxysiloxanes with n equal to 3 to 6.

It is generally preferred to have the mixtures of the invention with a low content of Volatile Organic Compounds (VOC), among which are those having a boiling point of up to 250 ℃ at atmospheric pressure. The VOC content is preferably less than 2% by weight, preferably less than 0.5% by weight and particularly preferably less than 0.2% by weight, based on the solids content.

However, the mixtures may also contain small amounts of free alcohols in addition to the oligomer mixtures of alkylalkoxysiloxanes. This free alcohol content in the powder can be built up, for example, by hydrolysis of alkoxy groups in the presence of higher air humidity. The amount of free alcohol is from 0 to less than 5% by weight, preferably less than 2% by weight, very preferably less than 1% by weight, based on the amount of organosilicon compound in the powder.

It is preferred for the mixtures according to the invention and for the mixtures suitable for use according to the invention that the organosilicon compound is water-insoluble or only sparingly water-soluble, is an aqueous dispersion, a water-dispersible or water-redispersible powder. If a well water-soluble organosilicon compound is used, it is preferably a powder which is soluble in water. For this purpose, the mixture may be a granular powder in which the water-soluble organic polymer and the organosilicon compound are coated and/or adsorbed on an inorganic substrate, regardless of the water solubility of the organosilicon compound, with care being taken in selecting an inorganic substrate in which the coated and/or adsorbed compound is readily re-dissolved by the substrate to function.

It is advantageous if the water-soluble organic polymers containing organosilicon compounds are insoluble or only sparingly soluble in water, and form stable dispersions in aqueous solution. It is often beneficial to coordinate the compounds so that the resulting dispersion still has equivalent physical properties such as pH, viscosity, particle size and color after 24 hours and no separation, i.e., settling of the dispersion particles, occurs. Since various water-soluble organic polymers can achieve desirable dispersion stability depending on the type of organosilicon compound, water-soluble organic polymers are desirable for a particular organosilicon compound, and incompatibility may occur when other organosilicon compounds are used. It is therefore necessary to adjust the organic polymer dissolved in water to the organosilicon compound. Preference is given to stabilizing systems which can convert the aqueous dispersion compositions obtained in a simple manner by drying into powders which are redispersible in water.

In general, suitable organic polymers which are soluble in water are solid as long as they do not dissolve at room temperature and are preferably higher molecular weight compounds. These are natural compounds such as polysaccharides, optionally chemically modified, synthetic high molecular weight oligomers and polymers having no or only weak ionic properties, and/or polymers which are prepared in situ using at least some of the monomers having ionic properties, for example by means of free-radical polymerization in an aqueous medium. It is also possible to use only one organic polymer dissolved in water, or to use different polymers in combination with one another. However, it is often advantageous for the organic polymer dissolved in water to have no or only a very small amount of carboxyl groups.

Polysaccharides and derivatives thereof which can preferably be used are polysaccharides and polysaccharide ethers which are soluble in cold water, such as cellulose ethers, starch ethers (amylose and/or amylopectin and/or derivatives thereof), guar ethers and/or dextrins. Synthetic polysaccharides such as anionic, nonionic or cationic heteropolysaccharides, in particular xanthan gum or Wellan gum, may also be used. The polysaccharide may, but need not, be chemically modified, for example, with carboxymethyl, carboxyethyl, hydroxyethyl, hydroxypropyl, methyl, ethyl, propyl, sulfate, phosphate and/or long chain alkyl groups. Other natural stabilizing systems are alginates, peptides and/or proteins such as gelatin, casein and/or soy protein. Very particular preference is given to dextrins, starches, starch ethers, casein, soy protein, gelatin, hydroxyalkyl cellulose and/or alkylhydroxyalkyl cellulose.

The artificially prepared water-soluble organic polymers may consist of one or more protective colloids, for example one or more polyvinylpyrrolidones and/or polyvinyl acetates having a molecular weight of 2000 to 400000, with a degree of hydrolysis which is completely or partially saponified and/or modified with amino, carboxyl and/or alkyl groups, preferably of about 70 to 100 mol%, in particular of about 80 to 98 mol%, and in 4% aqueous solutionPolyvinyl alcohols having a viscosity of preferably from 1 to 50mPas, particularly preferably from about 3 to 40mPas (measured to DIN53015 at 20 ℃), and also melamine formaldehyde sulfonates, naphthalene formaldehyde sulfonates, block copolymers of propylene oxide and ethylene oxide, styrene-maleic acid copolymers and/or vinyl ether-maleic acid copolymers. The higher molecular weight oligomers may be nonionic, anionic, cationic and/or amphoteric emulsifiers, such as alkylsulfonates, alkylarylsulfonates, alkylsulfates, sulfates of hydroxyalkanols, alkyl and alkylarylsulfonates, sulfonated fatty acids, sulfates and phosphates of polyethyleneoxide-alkylated alkanols and alkylphenols and also esters of sulfosuccinic acid, alkyl quaternary ammonium salts, alkyl phosphonium salts, polyaddition products of polyalkoxylates, e.g. 5 to 50Mol of ethylene oxide and/or propylene oxide per Mol of linear and/or branched C₆-to C₂₂Adducts of alkanols, alkylphenols, higher fatty acids, higher fatty acid amines, primary and/or secondary higher alkylamines, where the alkyl radicals are preferably all linear and/or branched C₆-to C₂₂-an alkyl group. Very particular preference is given to synthetic stabilizing systems, in particular partially saponified and optionally modified polyvinyl alcohols, one or more of whichPolyvinyl alcohols may be used together and optionally contain small amounts of suitable emulsifiers. Preferred synthetic stabilizing systems are in particular those having a degree of hydrolysis of from 80 to 98 Mol% and being in 4% aqueous solutionModified and/or unmodified polyvinyl alcohols having a viscosity of from 1 to 50mPas, and/or polyvinylpyrrolidone.

A wide variety of water-soluble organic polymers may also be used in the mixtures of the invention, for example a combination of one or more natural compounds and one or more artificially prepared compounds.

If the aqueous compositions (also referred to as dispersions or emulsions) or formulations according to the invention are used within the scope of the invention, the weight ratio of the organosilicon compound to the organic polymer used is in each case from about 95: 5 to 5: 95, in particular from about 85: 15 to 15: 85, and preferably from about 70: 30 to 30: 70, and very particularly preferably from about 60: 40 to 40: 60, the compositions or formulations preferably containing from 5 to 95 parts by weight, preferably from 10 to 70 parts by weight, more preferably from 15 to 60 parts by weight, particularly preferably from 20 to 50 parts by weight, and very particularly preferably from 25 to 40 parts by weight of water per 100 parts by weight of the composition or formulation.

If the water-soluble polymer and the organosilicon compound are formed as a dispersion, the particle size of the dispersion can be adjusted purposefully by the choice of the polymer, the weight ratio of the polymer to the organosilicon compound used, and by the manner and method of blending. If the mixture is dried to a powder and then redispersed or redispersed, the initial particle size is again generally obtained. It is generally preferred that the mixture which is dispersed, dispersible or redispersible in water, when dispersed or redispersed in water, has an average particle size of from about 0.1 to about 50 μm, especially from about 0.2 to about 30 μm. If the mixture is present in powder form, the mean particle size is preferably from about 20 to about 500. mu.m, in particular from about 50 to about 250. mu.m. However, the particle size can also exceed this range, with larger particles often being more suitable than smaller, closer to dust particles.

The particle size is determined in a conventional measurement method, wherein light scattering is preferably used and the particle size is given as a volume average.

The mixture which is dispersible or redispersible in water, when dispersed or redispersed in water, preferably has a solids content of about 5 to 75% by weight, in particular about 15 to 65% by weight and very particularly preferably about 30 to 50% by weight, and generally has a viscosity of about 100 to 100000mPas, preferably about 200 to 25000mPas, in particular about 300 to 10000mPas and very particularly preferably about 500 to 5000mPas, measured according to DIN 53015.

The mixtures according to the invention or mixtures suitable for the application according to the invention may also contain further additives. The kind of other additives is not limited. They generally play an important role in the use of the powders according to the invention, but this is not essential. Other organic polymers dissolved in water can also be added, and in this case they are preferably added in powder form.

The content of the additive is not substantially lower than the limit, based on the sum of the organic polymer and the organosilicon compound dissolved in water. For example, the content of the surface-active substance may be small and in the range of about 0.01% by weight or more, particularly about 0.1% by weight or more and preferably about 1% by weight or more, based on the solid content of the mixture. On the other hand, the mixtures according to the invention can also be mixed in substantially larger amounts of additives, for example fillers or dispersions and/or dispersion powders based on copolymers comprising emulsion polymers and/or suspension polymers based on, for example, Vinyl acetate, ethylene-Vinyl acetate-Vinyl versatate (Vinyl versatat), ethylene-Vinyl acetate- (meth) acrylate, ethylene-Vinyl acetate-Vinyl chloride, Vinyl acetate-Vinyl versatate- (meth) acrylate, pure (meth) acrylate, styrene-acrylate and/or styrene-butadiene. In this case, up to about 1000 parts, in particular up to about 500 parts and preferably up to about 100 parts of additives can be added relative to one part of the material according to the invention.

Preferred additives are in particular hydrophobicizing agents, such as fatty acids and salts and esters thereof, fatty alcohols, silanes, pore formers, wetting agents, defoamers, emulsifiers, film formers, hardening and setting accelerators, setting retarders, thickeners, dispersants, rheology control additives, such as cement liquefiers, polycarboxylates, polycarboxylate ethers, polyacrylamides and/or thickeners, corrosion inhibitors, such as ammonium alkyl benzoates, amino alcohols, gluconic acid and/or their alkali metal and alkaline earth metal salts, water-retaining agents, cellulose fibres and cellulose ethers, starch ethers, guar ethers, additives for reducing salt bloom, sedimentation and/or floating, fillers, and-when the mixture is in powder form-additives for reducing powder caking and/or film-forming, water-insoluble dispersion powders, and-when the mixture is in liquid form-film-forming polymer dispersions.

In addition, it is also possible to add as additives defoamers in powder and/or liquid form, wetting agents, alkyl-, hydroxyalkyl-and/or alkylhydroxyalkyl-polysaccharide ethers, such as cellulose ethers, for example cellulose ethers, starch ethers and/or guar ethers, where the alkyl and hydroxyalkyl groups are generally C₁-to C₄-groups, synthetic polysaccharides such as anionic, nonionic or cationic heteropolysaccharides, in particular xanthan or Wellan gums, cellulose fibres, dispersants, cement liquefiers, setting accelerators, hardening accelerators, setting retarders, pore formers, polycarboxylates, polycarboxylate ethers, polyacrylamides, fully and/or partially saponified and optionally modified polyvinyl alcohols, polyvinyl pyrrolidones, polyalkylene oxides and polyalkylene glycols, where the alkylene groups are generally C₂-and/or C₃Groups and also block copolymers, copolymers containing dispersions and dispersed powders, e.g. based on vinyl acetate, ethylene-vinyl acetate-vinyl versatate, ethylene-vinyl acetate- (meth) acrylate, ethylene-vinyl acetate-vinyl chloride, vinyl acetate-vinyl versatate- (meth) acrylate, ethylene versatateThose copolymers of alkenyl ester- (meth) acrylates, pure (meth) acrylates, styrene-acrylates and/or styrene-butadiene, hydrophobicizing agents, such as silanes, silane esters, siloxanes, silicones, fatty acids and/or fatty acid esters, thickeners, fillers, such as quartz and/or carbonate sand and/or ground powders, such as quartz sand and/or limestone powder, carbonates, silicates, layered silicates, precipitated silicic acids, light fillers, such as glass microspheres, polymers, such as polystyrene spheres, aluminosilicates, silicon oxide, aluminum silicon oxides, calcium silicate hydrates, silicon dioxide, aluminum silicates, magnesium silicates, aluminum silicate hydrates, calcium aluminum silicates, calcium silicate hydrates, aluminum-iron-magnesium silicates, calcium metasilicate and/or sulfide slags, and pozzolans, such as metakaolin and/or latent hydraulic constituents. Very particularly preferred additives are polymer dispersions, dispersion powders, polysaccharide ethers, liquefying agents and hydrophobicizing agents, in particular silanes, silane esters, fatty acids and/or fatty acid esters.

Likewise, the invention also relates to a method for producing the inventive mixtures, in which:

-in a first step at least 10% by weight, relative to the total amount of organosilicon compounds, of at least one organic polymer of (i) or (iii) dissolved in water is mixed with at least one organosilicon compound of (ii) or (iv), optionally the remainder of the organic polymer being added at the time of and/or after dispersion, optionally further additives being admixed before, during and/or after dispersion, and

-in a second step the dispersion obtained in the first step is dried, while further additives are added during and/or after the drying.

The mixtures according to the invention are prepared by the process according to the invention, wherein at least 10% by weight, preferably at least 20% by weight, of organic water-soluble polymer, relative to the total amount of organosilicon compounds, is mixed with the organosilicon compounds in a first step. This step is usually carried out in water, and the organic polymer is dissolved in water beforehand. Optionally the balance of organic polymer is added at and/or after dispersion or emulsification. Agitation mixing is generally preferred, and wherein higher shear forces are generally preferred. This step may be carried out batchwise, continuously, e.g. via a static mixer, or semi-continuously, at room temperature or at higher temperatures. The material may be stirred, dispersed and emulsified in the first step of the process of the invention to produce a composition which acts as a matrix for the second step.

In a further preferred embodiment, the organosilicon compounds are dispersed beforehand using nonionic, cationic and/or anionic emulsifiers, while the resulting dispersion is subsequently mixed with the organic water-soluble polymer.

Other additives may also be added before, during and/or after the dispersion, wherein it is very advantageous to add a pH buffer, such as sodium carbonate or sodium bicarbonate, to the aqueous phase. Other suitable additives are, for example, defoamers and/or wetting agents, low molecular weight polyalkylene glycols, fatty acids and/or fatty acid derivatives.

If the organosilicon compounds have a slightly higher viscosity, which makes it difficult to feed them accurately at room temperature, they can also be heated to facilitate feeding and dispersion. Alternatively, it is also possible to add a diluent to the organosilicon compounds in advance in order to adjust the viscosity, it being generally preferred for this diluent to be removed again subsequently, for example by distillation. It is also possible to use low-viscosity organosilicon compounds which do not have to be removed as diluents.

The resulting dispersion is usually further dried subsequently, and further additives can be added during and/or after drying, and drying is preferably carried out by means of spray drying, lyophilization, fluidized-bed drying, rotary drying, granulation or flash drying, spray drying being particularly preferred and being possible for example by means of spray rings, one-component nozzles or multi-component nozzles. It is often advantageous to add, during and/or after drying, anti-coagulants and/or fillers such as aluminium silicates, colloidal silica gel, fumed silica, ground clay, pearlite, vermiculite, gypsum, talc, cement, chalk, calcium/magnesium carbonate mixtures and/or diatomaceous earth.

If necessary, the aqueous dispersion can also be diluted with water to give a viscosity suitable for drying. The drying temperature is in principle not limited. However, in general, the temperature should not exceed about 200 ℃ and in particular about 180 ℃ in particular for reasons of safe handling. In order to obtain sufficiently effective drying, the temperature is preferably about 110 ℃ or higher, particularly preferably about 120 ℃ or higher. The outlet temperature of the gas stream formed during drying is generally from about 40 ℃ to 100 ℃, in particular from about 50 ℃ to 90 ℃.

In addition, the process according to the invention may also comprise the addition of further additives, and depending on the type and/or process, the additives mentioned are, for example, first mixed with the organic constituents and/or with the water-soluble organic polymeric protective colloids, added to the resulting aqueous dispersion and/or mixed into the resulting powder as a powder during and/or after drying. The liquid additive may also be sprayed onto the powder at or after drying. Liquid and/or water-soluble additives are preferably added before, during or after dispersion, and preferably the pulverulent additives are mixed with the powder obtained during or after drying.

If the other dispersion is also to be dried likewise, the dispersions to be dried can be mixed with one another and sprayed and dried together before drying, while spraying separately via two-or multi-component nozzles and then drying together simultaneously, but it is also possible to spray the two dispersions separately and then to mix the powders obtained with one another.

It is particularly preferred to apply the mixture according to the invention into and onto a material which contains at least one inorganic binding agent, in particular a hydraulic binding agent. In addition, they can also be used to protect metals, building materials, building stones, building components and/or buildings from corrosion, and the metals involved are usually encapsulated by inorganic building materials. In addition, the mixtures according to the invention are also suitable for hydrophobicizing such materials and for reinforcing stone materials.

The material containing at least one inorganic binder is preferably concrete, in particular reinforced concrete, expanded concrete, gas-hardening cement, fiber cement, steel fiber cement, expanded cement, casting cement, underwater concrete, roller cement, centrifugal casting cement, vacuum cement, self-sealing cement (SCC), seamless cement, disintegrating cement, drainage cement, foamed cement, shaped building elements made of high-strength and ultra-high-strength cement and/or glass-foamed cement, bricks, glazed tiles, mortars such as gypsum-and/or lime-and/or cement-mortars, in particular dry mortars, such as repair-and total-heat-protection mortars, joint and fiber-mesh binders, plywood mortars, mortars for bonding bridges, cement binders for parquet floors, cement substrates, levelling and/or troweling materials, sealing insulators, powder pigments and cement coatings, such as for example for coating steel or for improving the slurry of reinforced concrete in concrete reinforcement.

The mixtures of the invention can be applied to any substrate to protect them from corrosion. Non-limiting examples of such substrates are inorganic building materials, such as concrete, limestone, granite, lime, gypsum, marble, pearlite, clinker, porous fiber nets and tiles, natural stone, seamless floors, clay products, but also synthetic stone, wall constructions, facades, roofs and buildings, such as bridges, harbour constructions, residential constructions, factory constructions and public constructions, such as parking houses, railway stations or schools, but also shaped products, such as sleepers or L-stones, building elements and/or buildings, especially when they come into contact with, wrap or surround metals.

Likewise, the mixtures according to the invention can also be used as agents for stone reinforcement or in formulations for stone reinforcement, and as agents for hydrophobicizing and protecting against water damage or in formulations for such use.

The mixtures of the invention can also be used for coating cables, in particular for cable insulation and/or hydrophobicizing the cable surface.

The subject of the invention is likewise formulations or compositions comprising the mixtures according to the invention, in particular comprising or based on at least one mixture according to the invention or at least one mixture according to the invention and water. The mixtures are used, inter alia, in concentrations of from 0.01 to 25% by weight, in particular from about 0.1 to 10% by weight, preferably from about 0.2 to 5% by weight, based on the dry preparation or reagent, and care should be taken to comply with the respective specifications.

The formulations or compositions of the invention are, for example, but not exclusively, repair mortars, cement-based sealing materials, caulking materials, concrete, in particular reinforced concrete, expansion cement, gas-hardening cement, fiber cement, steel fiber cement, cellular cement, casting cement, underwater concrete, roller cement, centrifugal casting cement, vacuum cement, self-sealing cement (SCC), seamless cement, fracture cement, drainage cement, high-strength and ultra-high-strength cement, glass-foam cement, glazed tile, gypsum-and/or lime-and/or cement-mortar, repair-and total-thermal protection mortar, joint and fiber-web binders, levelling and scraping materials, sealing insulators, powder pigments and cement coatings, but also aqueous dispersions or solutions containing mixtures.

The subject matter of the invention is therefore likewise the substrates obtained according to a preferred embodiment of the invention, i.e. building materials, building stones, building components or buildings, which are based on the formulations according to the invention, the compositions according to the invention or the mixtures according to the invention.

The subject of the invention is also those articles based on the substrates of the invention. For example, objects made of the cement moulded parts according to the invention, such as shaped buildings, tunnels, bridges, streets, facades of buildings and containers.

In addition, another subject of the invention is therefore also a mixture obtained by the process according to the invention.

If powdery, the mixtures according to the invention are surprisingly distinguished by particularly good handling properties, storage stability and at the same time good flowability, so that they can also be incorporated very well into other compounds which may be liquid, pasty or powdery in nature.

In addition, the mixtures used according to the invention and the mixtures according to the invention surprisingly exhibit excellent dispersibility in water, redispersibility or solubility and have good wetting ability, so that they can be stirred very well into the material. If the mixtures are in the form of powders, they are ideally completely dispersed, redispersed or dissolved within a few seconds by gentle stirring on contact with water. In some cases, stronger shear forces may also be required. In any case, the shear forces occurring during the usually carried out stirring of the dry mortar are sufficient to completely disperse or redisperse the powder of the invention, whereby the particle size of the aqueous dispersion and the homogeneous distribution in the mass are obtained before drying.

Although in the mixtures according to the invention the organosilicon compounds, which are generally in liquid form, are encapsulated by water-soluble organic polymers so that the organosilicon compounds remain blocked during and after the drying step, it has surprisingly been found that they can also fully exert their effect when used in combination with inorganic binders and water. In addition, water-soluble organic polymers generally do not interfere during and after the production of the building material and with other properties of the fresh cement/fresh mortar and with the cured system. Instead, it may even beneficially contribute to very good processability, wettability, good dispersion and/or redispersibility. In addition, polymers that are soluble in water can also be used as binders, thereby increasing the physical strength of the bonded building material.

The mixtures according to the invention are therefore also distinguished by a particularly homogeneous distribution and excellent corrosion inhibition in building bodies and good alkali resistance of the building materials. In addition, harmful chloride ions and other water-soluble harmful substances, such as sulfates, which can lead to the formation of ettringite, are also removed from the building material. It is therefore particularly suitable for the production of various building bodies and for repairing and repairing buildings or building components, and when this mixture is used in inorganically bonded materials, both reinforcing or metal bars for building material wrapping and building stones or buildings, a significantly improved corrosion resistance is achieved compared with commercially available formulations.

Furthermore, it is particularly surprising that, in addition to the conventional hydrophobicization, the corrosion resistance of the building stones, building components or buildings and the corresponding reinforcing steel or metal bars thus treated, in particular in comparison with the corrosion protection measures customary on the market, can be improved more significantly by using the mixtures according to the invention when using silane products which have a hydrophobicization effect.

The invention is further illustrated by, but not limited to, the following examples.

Drawings

FIG. 1 shows a test body for carrying out the corrosion test.

FIG. 2 shows the corrosion current measurements on sensors covering 10mm test bodies P1 and P2.

Detailed Description

Examples

Example 1

Preparation of powder 1

With a propeller stirrer and under 1000Upm conditions in 15 minutes at 329.2g of a 4% solution with a degree of saponification of 88 mol%24% by weight polyvinyl alcohol having a viscosity of 4mPasIn an aqueous solution of (2) was emulsified in 100gFollowed by dilution with water to a solids content of 25% by weight. The mixture was sprayed with compressed air at an inlet temperature of 120 ℃ on a laboratory spray tower with a two-component nozzle and dried. As anti-sticking agent, 0.6 wt% calcined silicic acid and 9.4 wt% of a commercially available carbonate were added, both relative to the shaped powder. A white powder which is free-flowing and well redispersible in water is obtained in good yield and which, when rubbed between the fingers, does not itself give a sticky feel and can therefore contain the propylalkoxysiloxane mixture used in well-encapsulated form.

Example 2

Preparation of powder 2

Example 1 was repeated, wherein the mixture obtained was not diluted with water. The solids content was 37.9% by weight and the Brookfield viscosity, measured with Spindel 3 at 20 rpm and 25 ℃, was 1590 mPas. Spray drying was carried out using a spray pan at an inlet temperature of 150 ℃. A white powder which is free-flowing and which wets well and redisperses well is obtained in good yield and which disintegrates into primary particles in a very short time when stirred with water.

Example 3

Preparation of powder 3

329.2g of a solution having a saponification degree of 88 mol% and 4% were mixed in analogy to example 224% by weight aqueous polyvinyl alcohol solution having a viscosity of 4mPas and 200.0g of 50% by weight polyvinyl alcohol stabilized with an emulsifierAqueous emulsion, dilution, drying and mixing with an anti-sticking agent. A white powder which is free-flowing, well-wetting and well-redispersible in water is obtained in good yield and which, when rubbed between the fingers, does not itself give a sticky feel and can therefore contain the siloxane used in well-encapsulated form.

Example 4

Preparation of powder 4

In 15 minutes with a propeller stirrer and at 1000 rpm at 595.7g of a 4% solution with a saponification degree of 88 mol%40g of liquid silane based on isobutyltriethoxysilicane were emulsified in a solution of 4mPas in 24% by weight of polyvinyl alcohol and subsequently diluted with water to a solids content of 25% by weight. The mixture was sprayed with compressed air at an inlet temperature of 120 ℃ on a laboratory spray tower with a two-component nozzle and dried. As anti-sticking agent, 0.6 wt% calcined silicic acid and 9.4 wt% of a commercially available carbonate were added, both relative to the shaped powder. A white powder which is free-flowing, well wettable and well redispersible in water is obtained in good yield and which, when rubbed between the fingers, does not itself give a sticky feel and can therefore contain the silane preparation used in well-encapsulated form.

Example 5

Powders 5 to 10 were prepared according to EP 0228657:

analogously to the examples described in EP0228657, in an aqueous polyvinyl alcohol solution (having a degree of saponification of 88 mol% and a 4% solution)24.3% by weight polyvinyl alcohol solution with a viscosity of 4 mPas) to a non-aqueous component content of 40% by weight, see Table 1. The stability of the sprayed material was evaluated after 2 and 12 h. As a measure of stability, the corresponding stability is given in cm in Table 3After the previous stirring process, the spray material was then sprayed and dried in a laboratory spray dryer (inlet temperature 135 ℃, outlet temperature 76 ℃) using a two-material nozzle (air pressure 3.5 bar).

TABLE 1

Example No. 2

5a

5b

5c

5d

5e

5f

Powder number

5

6

7

8

9

10

EP228657 examples

3a)

1a)

5a)

7a)

11

10

Siloxane content

80％

90％

95％

90％

90％

90％

PVOH content

20％

10％

5％

10％

10％

10％

After 2h and 12h of stability

00

0.11.0

1.53.5

00.5

00.1

00.5

Yield of the product

Medium and high grade

Difference (D)

Very poor

N/Ab)

N/Ab)

N/Ab)

a) The corresponding propylsiloxane was used instead of methylsiloxane

b) These mixtures were not sprayed because of the poor yield of powders 5-7.

The spray material was unstable except for example 5a, which contained 20% polyvinyl alcohol, and was therefore stirred before spray drying. Only examples 5a-5c were dried due to poor sprayability.

The yield becomes significantly worse as the PVOH content decreases and also increasingly sticky wall-sticking is obtained in the spray tower. The powder was also sticky when rubbed over the fingers, indicating that the silicone was not properly encapsulated.

The spray materials and powders prepared according to the teaching of EP0228657 clearly show a slightly inferior performance in terms of spray material stability, sprayability. In addition, they also exhibit poor wettability and strongly slow redispersibility, which significantly increases the difficulty of use in building materials. Therefore, powders based on this composition have to be prepared in an expensive way. However, these compositions can also be used in the application according to the invention if the preparation process and optionally further additives are selected such that the resulting powder meets the requirements with regard to storage capacity, wettability and redispersibility.

Example 6

Application technique detection-determination of water absorption coefficient of cement/sand-mortar

To evaluate the corrosion inhibition and possible hydrophobing of the powder against the liquid starting material, the water absorption coefficient after 24 hours was determined in accordance with the teaching of DIN 52617. A mortar base mixture consisting of 25% by weight of Portland cement CEM I42.5N and 75% by weight of standard sand according to DINEN 196-1 was mixed with the active ingredients listed in Table 2 and stirred with 12% by weight of water, relative to the dry formulation, within 60 seconds using a 60mm propeller stirrer at a speed of 950 rpm. After a curing time of 3 minutes, the mortar was again quickly stirred by hand and then filled into plastic ring molds of 8cm diameter and 2cm height and the surface at the height of the mold was removed with a spatula. The test specimens were stored at 23 ℃ and 50% relative air humidity for 14 days and were isolated after the first day. After weighing the test bodies, they were placed in water for 24 hours and then weighed again after drying to remove the water adhering to the surface. The water absorption coefficient ω is then calculated from the weight difference, the surface area of the test body and the duration of the storage in water in accordance with DIN52617₂₄. The tests were carried out with active ingredients containing liquid silanes and with the powders used according to the invention. No significant change in coagulability was observed.

TABLE 2

After 24 hours of immersion in water and without PVOH in the cement/sand-mortar, the water absorption coefficient values ω of powders 3 and 1 compared to the liquid active ingredient used₂₄. The water absorption coefficient is determined in accordance with DIN52617 and is measured in [ kg/m ]^2*h^0.5]And (4) showing. The amounts added are adjusted so that the amounts of active ingredient relative to the amount of silane or siloxane are 1.8% by weight, based on the dry ingredients of the mortar mixture used.

The water absorption coefficient was calculated as described above using powder 2, but using a mortar containing a mortar base mixture consisting of 34% by weight of portland cement CEM I42.5, 59.8% by weight of quartz sand 0.1 to 0.5mm, 3% by weight of lime hydrate, 0.2% by weight of cellulose ether Tylose MH 10007P4 and 3% by weight of redispersion powder based on ethylene-vinyl acetate copolymer and kneading with 22% by weight of water.

TABLE 3

Water absorption coefficient omega of powder 2 in mortar (see text) after 24 hours immersion in water₂₄. The water absorption coefficient is determined in accordance with DIN52617 and is measured in [ kg/m ]^2*h^0.5]And (4) showing.

	Water absorption coefficient omega24
		Without additives	0.269
0.5 wt.% of powder 2	0.196

The results in Table 2 clearly show that the polyvinyl alcohol used for spraying has no substantial effect on the water absorption properties of the mortar after curing and therefore also on the water absorption coefficient. In addition, the values in Table 3 show that a minimum amount of the powder according to the invention already has the effect of significantly reducing the water absorption. This also reduces the penetration of chloride when placed in chloride-containing water, which makes steel corrosion impossible in each case or at least considerably delayed.

Example 7

Determination of the Corrosion inhibition of the powders according to laboratory tests

The purpose of the test is to quantitatively determine the effect of the inhibitor in a laboratory test. In this case, standard methods (for example tests according to ASTM) are not used, since the special properties of the powders, in particular based on silicon compounds, do not or only to a small extent play a role. Therefore, drying and wetting cycles are used in the laboratory to test the effects of periodic climates. In these cases, the drying effect of the cement, which affects the corrosiveness, may disappear.

The corrosion conditions were continuously measured using pre-formed cement blocks with side lengths of 15cm each equipped with three sensors to monitor the corrosion rate and corrosion status. The cement formulations used and the preparation conditions are summarized in tables 2 to 3. The test body for carrying out the corrosion test is depicted in fig. 1.

TABLE 4

Formulation of cement for use with portland cement CEM I

3 reinforcing bars with a diameter of 8mm and a length of 45mm were implanted as inductors. Their cement coverage was 10mm, 28mm and 46 mm. To measure the corrosion current, these sensors were each connected to a cathode (only the cathode is depicted in fig. 1).

The climate conditions as would occur during seasonal alternation were simulated by immersion in the electrolyte at 35 c and 2 days through a 5 day wet/dry cycle. The wetting/drying cycle carried out in the test field usually occurs only twice a year in buildings. Therefore, the chloride infiltration process can be simulated strongly accelerated under these experimental conditions (here, 2 weeks corresponds to about 1 year).

Two different samples were prepared using powder 1 of example 1. Using the cement compositions described in table 4, sample bodies P1 and P2 were prepared in which the amounts of powder were 2% (P1) and 4% (P2), respectively, with respect to the cement content. The amounts of the powders used correspond to the content of active ingredient, 1% by weight and 2% by weight, respectively, based on the organosilicon compound.

After 4 days, the test specimens were isolated and subsequently stored at room temperature at 100% relative air humidityAnd (4) week. The periodic treatment pattern was then started while the samples were immersed in 1M aqueous NaCl solution, respectively.

The corrosion current profiles of these samples obtained on inductors covering 10mm of sample P1 (containing 2% by weight of powder 1) and P2 (containing 4% by weight of powder 1) are shown in fig. 2a and 2 b. Sample P2 showed no corrosion. In contrast, the activation of corrosion was observed on the lowermost reinforcing layer (10mm) in the reference sample body P1. Sample P1 showed some reduction in corrosion rate over time, which may be attributed to some inhibition. However, according to these data, a powder concentration of 2% by weight must be evaluated as an effective corrosion prevention too small. In contrast, a concentration of active effective ingredient of about 2% by weight of silicon compound based on the cement content (containing 4% by weight of powder 1) clearly has a corrosion-inhibiting effect.

Claims (1)

1. Use of at least one water-dispersible, redispersible or soluble mixture for protecting a substrate against corrosion, said mixture being based on at least:

(i) at least one organic polymer soluble in water, and

(ii) at least one organic silicon compound,

wherein the organosilicon compound is an organosilicon compound having at least one Si-O-Si bond and is based on an oligomer mixture of alkylalkoxysiloxanes containing from 50 to 100% by weight of alkylalkoxysiloxanes and having a degree of oligomerization of from 2 to 20, and wherein the substrate is a metal and the corrosion refers to a chemical reaction of the material with its surroundings.

2. The use of claim 1, wherein the metal is encapsulated by an inorganic building material.

3. The use according to claim 1, wherein the mixture is added or contacted during the preparation of the inorganic building material.

4. A mixture dispersible, redispersible or soluble in water based on:

(iii) at least one organic polymer soluble in water, and

(iv) at least one organosilicon compound containing at least one Si-O-Si bond,

wherein the content of organic polymer (iii) is 40 to 80 wt.%, based on the total amount of organic polymer (iii) and organosilicon compound (iv), and the organosilicon compound having at least one Si-O-Si bond is based on an oligomeric mixture of alkylalkoxysiloxanes which contains from 50 to 100 wt.% of alkylalkoxysiloxanes and has a degree of oligomerization of 2 to 20

And the oligomer mixture satisfies the general formula I of an alkylalkoxy siloxane:

(R’’)Si(OR’’’)_xO_y(I)

wherein the radicals R '' are identical or different and R '' is a linear, branched or cyclic alkyl radical having 1 to 18C atoms, the radicals R '' 'are identical or different and R' '' denotes hydrogen or a linear or branched alkyl radical having 1 to 4C atoms, and 1.0< x <2.0 and 0.5< y ≦ 1.0, with the proviso that (2y + x) = 3.

5. The mixture as claimed in claim 4, wherein the oligomeric mixture of alkylalkoxysiloxanes used for the preparation of the mixture has from 70 to 100% by weight of alkylalkoxysiloxanes having a degree of oligomerization from 2 to 10.

6. The mixture according to claim 4 or 5 or the use according to claim 1, wherein the organic polymer dissolved in water is a synthetically prepared polymer in the form of modified and/or unmodified polyvinyl alcohol having a degree of hydrolysis of 70 to 100 mol%, a Hnanopler viscosity of 1 to 50mPas, measured as a 4% solution in water at 20 ℃ according to DIN53015, and/or polyvinylpyrrolidone, polyacrylate, polymethyl acrylate, polyalkylene oxide and/or polymaleate.

7. The mixture of claim 4 or 5 or the use of claim 1, wherein the organic polymer dissolved in water is a natural and/or synthetically prepared biopolymer and is starch, starch ether, dextrin, cellulose ether, casein and/or soy protein.

8. The mixture of claim 4 or 5 or the use of claim 1, wherein the mixture which is dispersible or re-dispersible in water has an average particle size of from 0.1 to 50 μm when dispersed or re-dispersed in water.

9. The mixture of claim 4 or 5 or the use of claim 1, wherein the mixture which is dispersible or re-dispersible in water or soluble in water has an average particle size of from 20 to 500 μm.

10. The mixture according to claim 4 or 5, wherein the mixture further comprises other additives, the further additives are selected from hydrophobicizing agents, fatty acids and their salts and esters, fatty alcohols, silanes, pore formers, wetting agents, defoamers, emulsifiers, film-forming aids, hardening and setting accelerators, setting retarders, thickeners, dispersants, rheology control aids, cement liquefiers, polycarboxylates, polycarboxylate ethers, polyacrylamides and thickeners, corrosion inhibitors, alkylammonium benzoates, aminoalcohols, gluconic acid and/or their alkali metal and alkaline earth metal salts, water-retaining agents, cellulose fibers, cellulose ethers, starch ethers, guar ethers, additives for reducing salt bloom, sedimentation and/or floating, fillers, and additives for reducing powder caking, film-forming, water-insoluble dispersion powders and film-forming polymer dispersions.

11. A process for preparing the mixture of claim 4 or 5, wherein:

-in a first step at least 10% by weight, relative to the total amount of organosilicon compounds, of at least one water-soluble organic polymer of (iii) is mixed with at least one organosilicon compound of (iv), optionally the remainder of the organic polymer being added at and/or after dispersion, optionally further additives being admixed before, during and/or after dispersion, and

-in a second step the dispersion obtained in the first step is dried, while further additives are added during and/or after the drying.

12. The process of claim 11, wherein the drying is carried out in a second step by spray drying, lyophilization, fluid bed drying, rotary drying, granulation, or flash drying.

13. Use of a mixture according to claim 4 or 5 or prepared according to claim 11 or 12 in and/or on a material containing at least one inorganic binder.

14. Use of a mixture according to claim 13, wherein the material comprising at least one inorganic binder is selected from the following series: concrete, reinforced concrete, expansive cement, gas-hardening cement, fiber cement, porous cement, steel fiber cement, casting cement, underwater concrete, roll-in cement, centrifugal casting cement, vacuum cement, self-sealing cement, seamless cement, fracture cement, drainage cement, high-strength and ultra-high-strength cement, glass-foaming cement, glazed brick, gypsum mortar and/or lime mortar and/or cement mortar, repair mortar, all-thermal protective mortar, joint binder, fiber mesh binder, leveling material, troweling material, sealing insulator, powder pigment, and cement coating.

15. Use of a mixture according to claim 4 or 5 or prepared according to claim 11 or 12 for protecting metals against corrosion, wherein the metals are encapsulated by an inorganic building material.

16. Use of the mixture according to claim 4 or 5 or prepared according to claim 11 or 12 for protecting building stones, building components, buildings against corrosion.

17. Use of the mixture according to claim 4 or 5 or prepared according to claim 11 or 12 as a composition for reinforcing stone material or in a formulation for reinforcing stone material.

18. Use of the mixture according to claim 4 or 5 or prepared according to claim 11 or 12 for coating cables, for cable insulation and/or for hydrophobicizing cable surfaces.

19. Formulation based on water and at least one mixture as claimed in claim 4 or 5 or prepared according to claim 11 or 12.

20. Formulation or composition comprising at least one mixture according to claim 4 or 5 or prepared according to claim 11 or 12, wherein the mixture is contained in the formulation or composition at a concentration of 0.1 to 10% by weight, based on the dry ingredients, for use according to claim 13 or 15.

21. Substrate or article based on a formulation or composition according to claim 19 or 20 or at least one mixture according to claim 4 or 5 or prepared according to claim 11 or 12.