Method for producing laminate of wood and cement-based composition

Abstract

The invention relates to a method for producing a laminate, characterized in that (i) a wooden element is provided, (ii) the upper surface of the wooden element is coated with an adhesive applied in liquid form, comprising at least one polymer that is liquid at room temperature and contains silane groups, at least one liquid epoxy resin, and at least one amine hardener, (iii) the applied adhesive is covered with a layer of a liquid cementitious composition while still wet, and (iv) the liquid cementitious composition and the adhesive are each cured. This method allows a highly durable bonding of wooden and cementitious elements in a wet-on-wet manner that is easy to implement. The laminate resulting from this method is relatively light, stable, robust, and particularly suitable as a sustainable component in above-ground structures, in particular as a ceiling element.

Description

[Technical field]

[0001] The present invention relates to a process for manufacturing a laminate, to the laminate, and to its use as a component in building construction. [Background technology]

[0002] Wood, a renewable raw material, has been used as a building material since time immemorial and, apart from its sustainability, has further advantages over cement-based building materials such as concrete, in particular its high tensile strength in addition to its low density and attractive aesthetics. The disadvantages of wood as a building material lie mainly in its insufficient fire resistance and acoustic conductivity, which makes it difficult to achieve fire and sound protection, as well as its expansion and contraction properties under the influence of moisture. Bonding wood to concrete as a hybrid system (wood-concrete composite) has the advantage of combining the advantages of the two building materials with each other, in that wood can absorb the tensile forces and the compressive forces of concrete. This can be used, for example, for roof structures with a relatively low specific weight and low overall height, as well as load-bearing capacity and bending stiffness, and therefore also for large spans with good fire and sound protection properties. To achieve such properties, it is important that wood and concrete, which are fundamentally different materials, are bonded to each other with maximum shear resistance and durability by suitable bonding methods.

[0003] A typical procedure for gluing wood to concrete is to glue the hardened concrete body to the wood using a metal fastening system such as screws, bolts, clamps or anchors. Such a bond is stable and durable, but complex to manufacture and often has an unsatisfactory appearance. A further option is to establish a mechanically stable interdigitation with the concrete by means of notches or slots in the wood, for example in that the liquid concrete hardens in contact with the wood. However, such a bond is often insufficiently stable and durable, especially since the wood moves as a result of contraction or expansion due to increased humidity or mechanical stress.

[0004] It is also known to bond wood to hardened concrete, the adhesive used for this usually being an epoxy resin adhesive. Typically, bonding requires complex pre-treatment of the concrete surface, in which the cement skin on the concrete surface is mechanically removed, to avoid interruption of the adhesive cure and ensure a stable and durable bond.

[0005] It is particularly attractive to establish a stable and durable bond between wood and concrete or mortar by pouring liquid concrete or mortar onto an adhesive-coated wood surface without the need for slits or other notches required to mechanically engage the wood surface, but the demands on such adhesives are high with regard to mechanical properties, insensitivity to the highly alkaline solvents of liquid concrete, and durability.

[0006] M.Brunner et al., Materials and Structures (2007) 40:119-126, describes the bonding of wood and concrete with epoxy resin adhesives in a wet-on-wet method. However, the epoxy resin adhesives used are difficult to handle due to the high heat generation after mixing, and are very hard and relatively brittle after curing. This means that the laminates easily break at the adhesive interface as a result of the expansion and contraction properties of wood under mechanical stress or under humidity changes. Furthermore, the curing reaction of the epoxy resin adhesive is often hindered by the fresh concrete, resulting in the construction of insufficient bond strength and therefore no durable and / or permanent bond. There is therefore a need for a simple process that can establish a durable and permanent bond between wood and concrete bodies.

[0007] Curable compositions based on polymers containing silane groups and epoxy resins are known, for example from EP 370464 or US 2017 / 0292050 A1. They have good adhesive properties, for example on hardened water-wet concrete. It was not previously known that such adhesives can cure completely and develop high adhesive strengths even in contact with freshly applied liquid concrete. Summary of the Invention [Problem to be solved by the invention]

[0008] It is therefore an object of the present invention to provide a method for bonding wood and cementitious materials which uses the cementitious material in liquid form and allows for a highly durable and permanent bond. [Means for solving the problem]

[0009] This object is surprisingly achieved by a method for producing a laminate according to claim 1. It involves coating the wood with an adhesive applied in liquid form, comprising at least one polymer containing silane groups, at least one liquid epoxy resin and at least one amine hardener, and then overcoating the still mainly uncured adhesive with a liquid cementitious composition, where the cementitious composition and the adhesive are finally cured.

[0010] The method of the invention is easy and fast to carry out and, surprisingly, the adhesive used allows for overlaying with a liquid cementitious composition such as freshly made concrete or mortar with water in a wet-on-wet manner without the problems known from the prior art. In particular, the freshly mixed adhesive does not generate excessive heat during application and open time, which causes problems during application and open time, and after overlaying with a liquid cementitious composition such as fresh concrete or fresh mortar, the applied, still largely uncured adhesive cures perfectly and develops high adhesive strength to the wood and to the hydraulic hardening cementitious composition which also cures in parallel. The hardening results in a laminate in which the cementitious composition and the wood are fixedly and permanently bonded to each other via the hardened adhesive. Even after storing the laminate in water at room temperature for 24 hours, even if the wood has undergone some expansion due to water absorption, the bond between the hardened cementitious composition and the wood is sufficiently mechanically stable.

[0011] Compared with epoxy resin adhesives that do not contain polymers with silane groups, the adhesives used according to the present invention have perfect curing, relatively low heat generation, and mechanical properties that are more suitable for this application.In particular, they exhibit high tensile and impact resistance, but pure epoxy resin adhesives are typically hard and relatively rigid in nature, making them less suitable for bonding between rigid, cured cementitious compositions and wood that moves according to ambient conditions.

[0012] The method of the present invention allows the production of laminates from wood and concrete or mortar, which have excellent suitability as sustainable components in building construction, especially as roof elements, which have high demands in terms of aesthetics, sound insulation, strength and stability. Furthermore, the method of the present invention allows the use of hardwoods in the building sector, which often cannot be used due to their high tendency to absorb water compared to softwoods. The adhesive used in the method of the present invention, in addition to its function as a viscoelastic interlayer, also functions as a moisture barrier, protecting the wood side of the laminate from the ingress of moisture from the concrete side. The laminates obtained from the method are relatively light, stable and durable, and are particularly suitable as sustainable components in building construction, especially as roof elements.

[0013] Further aspects of the invention are the subject matter of further independent claims. Particularly preferred embodiments of the invention are the subject matter of the dependent claims.

[0014] How to carry out the invention The present invention relates to (i) timber is provided; (ii) the upper surface of the wood is coated with an adhesive applied in liquid form, comprising at least one polymer containing silane groups that is liquid at room temperature, at least one liquid epoxy resin, and at least one amine hardener; (iii) the wet applied adhesive is overcoated with a liquid cementitious composition; (iv) The liquid cementitious composition and the adhesive are each allowed to harden. The present invention provides a method for producing a laminate, comprising the steps of:

[0015] "Cementitious composition" refers to a hydraulic setting composition containing cement, particularly mortar or concrete.

[0016] "Liquid cementitious composition" refers to a water-containing cementitious composition that has not yet hydraulically set or has only slightly set and is therefore still free-flowing.

[0017] "Inorganic filler" refers to powdered or granular inorganic materials that are not hydraulic binders.

[0018] A "wet" applied adhesive is one that will stick to an LDPE pipette when tapped with the pipette.

[0019] A "silane group" refers to a silyl group bonded to an organic radical and having one to three, specifically two to three, hydrolyzable alkoxy radicals on the silicon atom.

[0020] "Aminosilane," "mercaptosilane," or "hydroxysilane" refer to organosilanes that, in addition to the silane group, have an amino, mercapto, or hydroxyl group, respectively, on the organic radical.

[0021] The "silicon content" of a polymer containing silane groups refers to the silicon content of the polymer in weight percent, based on 100 weight percent polymer.

[0022] Substance names beginning with "poly", such as polyamine or polyol, officially refer to substances that contain two or more of the functional groups contained in the name per molecule.

[0023] "Amine hydrogen" refers to the hydrogen atoms of primary and secondary amino groups.

[0024] "Amine hydrogen equivalent" refers to the mass of an amine or amine-containing composition that contains one molar equivalent of an amine hydrogen, and is expressed in units of "g / eq."

[0025] "Epoxide equivalent" refers to the mass of an epoxy-containing compound or composition that contains one molar equivalent of epoxy groups, and is expressed in units of "g / eq."

[0026] "Molecular weight" refers to the molar mass (grams per mole) of a molecule. "Average molecular weight" refers to the number average M nwhich is typically determined by gel permeation chromatography (GPC) using polystyrene as a standard.

[0027] A "shelf-stable" composition is one that can be stored in a suitable container at room temperature for an extended period of time, typically at least 3 months and up to 6 months or more, without undergoing any change in its scope of use.

[0028] The "pot life" of an adhesive refers to the maximum time, after mixing the components and before application, during which the mixed adhesive is sufficiently free-flowing and has good ability to wet the wood surface.

[0029] The "open time" of an adhesive refers to the maximum time between mixing the components and overcoating the adhesive with a cementitious composition during which a cohesive bond is achieved.

[0030] "Room temperature" refers to a temperature of 23°C.

[0031] All industry standards and guidelines referenced in this document refer to the version in effect as of the original filing date unless otherwise stated.

[0032] Weight percent (wt %) refers to the percentage by mass of a component in a composition, based on the entire composition, unless otherwise specified. The terms "mass" and "weight" are used interchangeably herein.

[0033] The wood preferably consists of hard or soft wood, preferably beech or spruce, these types of wood have high mechanical durability and are widely used in the building industry.

[0034] In particular, the wood consists of beech wood, which is widely available and is particularly hard and durable, but which has so far been relatively rarely used as a building material due to its high tendency to expand under the influence of moisture.

[0035] Suitable woods are all kinds of wooden moldings. Preference is given to moldings having at least one flat surface.

[0036] The wood is preferably provided with the horizontal plane facing upwards (hereinafter also referred to as the "top surface").

[0037] The wood preferably has the shape of a cube or a rectangular parallelepiped, in particular a rectangular parallelepiped. In the case of a rectangular parallelepiped, it is preferably arranged so that one of the largest faces is at the top and thus forms the top face. Hereinafter, the side perpendicular to the top side is also referred to as "thickness".

[0038] The wood preferably has a thickness in the range of 10 to 300 mm, preferably 20 to 200 mm. The thickness of the wood (H) is, for example, D shown in FIG. H is shown as:

[0039] The upper surface of the wood preferably has a length in the range of 0.3 to 20 m, preferably 1 to 10 m. The length of the wood (H) is shown as L in FIG.

[0040] The upper surface of the wood preferably has a width in the range of 50 to 2,000 mm, preferably 100 to 1,500 mm, in particular 150 to 1,000 mm. The width of the wood (H) is shown as B in FIG.

[0041] The timber preferably has a rectangular parallelepiped shape with a length greater than its width and a width greater than its thickness. Such timber is also called a board, beam or bar.

[0042] The wood may consist of unglued solid wood or of glued and / or interlocking laminated wood made of thin strips or square bars. In particular for large pieces of wood, 1 m or more in length and 150 mm or more in width, laminated lumber is preferred due to its particularly excellent mechanical durability and dimensional stability.

[0043] The wood may be pre-treated prior to application of the adhesive in step (ii).The wood is preferably dust-free.

[0044] Mechanical pretreatment such as roughening or machining grooves or slits is possible but is not required for good adhesion and is therefore not preferred.

[0045] Pretreatment with an activator or primer is also possible, but is likewise unnecessary for good adhesion.

[0046] Preferably, the wood is not primed prior to step (ii) as such a method is particularly quick and simple and results in a durable and stable laminate.

[0047] The adhesive components are mixed to form a macroscopically homogeneous liquid, particularly immediately prior to application in step (ii). Mixing can be performed batchwise or continuously, by automatic mixing and metering units with static mixers, or by utilizing dynamic mixers.

[0048] Preferably, the freshly mixed adhesive has a slightly thixotropic, fluid consistency so that it can be spread precisely with a squeegee or trowel onto the top surface of the wood without excessive flowing.

[0049] The components of the adhesive are preferably present in at least two separately packaged components before being mixed, the first component containing the amine hardener, the second component containing the liquid epoxy resin, and the polymer containing silane groups being a component of the first and / or second component, or a separately packaged third component. The polymer containing silane groups is preferably a component of the first and / or second component, in particular of the first component. The further components of the adhesive may be present in the first or second component, or as a component of the further component. The further components are suitably distributed between the components so that the first and second components and the further components are storage stable in the moisture-proof package.

[0050] Following mixing, in step (ii), the liquid adhesive is applied to the top surface of the wood, suitably within its pot life.

[0051] The application is preferably effected by injection or application from a cartridge or application gun and, if necessary, spread by suitable means, in particular by a squeegee, trowel or doctor. Application by spraying is likewise possible.

[0052] Preferably, the adhesive of step (ii) is applied with a layer thickness in the range of 0.1 to 10 mm, preferably 0.2 to 7 mm, in particular 0.3 to 5 mm. The layer thickness of the adhesive (K) is, by way of example, shown in FIG. K is shown as:

[0053] Mixing of the components and application of the adhesive is preferably carried out at ambient temperature, which is typically in the range of about 5 to 45°C, preferably about 10 to 35°C.

[0054] Once the components are mixed, a chemical reaction begins the hardening of the adhesive, which gradually increases the viscosity of the liquid adhesive until it gels, resulting in a solid adhesive with a surface that may still be tacky at first, but eventually dries.

[0055] During the adhesive's open time, when the adhesive is still wet, i.e. uncured, the wet applied adhesive is overcoated with the liquid cementitious composition in step (iii). Step (iii) is therefore performed before the applied adhesive forms a skin on its surface. Such a procedure is also called "wet-on-wet" application.

[0056] Step (iii) is preferably carried out at a time when the viscosity of the adhesive has already increased to some extent as a result of the initial crosslinking reaction of the reactive groups. The increase in viscosity is observed 5 minutes after mixing the components of the adhesive at a shear rate of 10 s at 20 °C. -1It is preferably at least 10%, particularly preferably at least 30%, based on the initial viscosity measured using a cone and plate viscometer.

[0057] Preferably, the wood to which the liquid cementitious composition is applied in step (iii) is provided with formwork elements on the outside, for example on the extension of the side edges, so that the liquid cementitious composition remains on the surface of the wood after application and cannot flow out. In FIG. 1, the thickness D of the wood (H) is H The formwork elements are preferably of a thickness D of timber such that, when completely filling the formed volume with the liquid cementitious composition, they form a complete formwork having a suitable height for the application of adhesive and cementitious composition. H The height of the formwork element preferably corresponds to the thickness D of the stack, as shown by way of example in FIG.

[0058] Suitable formwork elements are boards or other devices that can be removed after the cementitious composition has hardened, as is customary in concrete construction.

[0059] Preferably the formwork elements are installed before or after step (ii), in particular before step (ii).

[0060] Before step (iii), optionally, a reinforcing bar is attached on the applied adhesive, and the reinforcing bar is placed with a spacer so that when the adhesive is overcoated, the reinforcing bar is placed in the cementitious composition and surrounded by the cementitious composition. This allows a laminate with particularly high strength. Any of the reinforcing bars normally used in mortar or concrete engineering can be used. Likewise, reinforcing elements made of fibers or fabrics, for example glass fiber or carbon fiber fabrics, are suitable. Suitable polypropylene fibers are available, for example, under the trade name SikaFiber® (Sika). Suitable carbon fiber layered fabrics are available, for example, under the trade name Sika® CarboDur® (Sika).

[0061] The cementitious composition is prepared by mixing the components before application, where it is possible to use a dry mixture containing the cement and further additives, which is constituted with water immediately before application.

[0062] The liquid cementitious composition in step (iii) preferably has a pourable consistency, but not too thin, and where the water content is such that it provides high strength together with low shrinkage on hardening.

[0063] During application, the preferably attached formwork elements prevent the flow-out of the cementitious composition. The formwork elements, together with the coated upper surface of the wood, preferably form a mold for the liquid cementitious composition, the coated upper surface of the wood forming the bottom. The formwork elements preferably protrude above the coated upper surface of the wood to such an extent that the depth of the mold corresponds to the desired layer thickness of the cementitious composition.

[0064] Preferably, the liquid cementitious composition in step (iii) is applied in a layer thickness ranging from 10 to 300 mm, preferably from 20 to 200 mm, in particular from 30 to 100 mm. The layer thickness of the cementitious composition (Z) is, for example, shown in FIG. Z is shown as:

[0065] In step (iii), the liquid cementitious composition is applied, preferably so as to obtain a horizontal surface. The cementitious composition is optionally compacted by a suitable method. Suitably, the surface of the cementitious composition is smoothed towards the end of application, for example with a spatula or a brick trowel.

[0066] Subsequently, in step (iv), the liquid cementitious composition and the adhesive are allowed to harden.

[0067] Preferably, the hardening in step (iv) is carried out by leaving it at ambient temperature, optionally protecting the cementitious composition on the surface from drying with a polymeric film.

[0068] The adhesive cures to its final strength by chemical reaction of the reactive groups present, particularly silane, epoxy and amino groups, with the amine hydrogens. At the same time, the underlying cementitious composition also cures by hydraulic hardening of the cement present, eventually reaching its final strength. During the hardening process, high bond strength of the adhesive to the wood and the hardened cementitious composition is developed, so that the laminate resulting from this method has a stable bond between the wood and the cementitious composition layers.

[0069] The duration of the curing process depends on the ambient temperature, the components used in the adhesive or cementitious composition, and the presence of accelerators in the composition. Typically, any formwork elements present are removed after about 1-2 days, and the laminate reaches its final strength after several days or weeks at room temperature.

[0070] The adhesive used in the method comprises at least one polymer containing silane groups that is liquid at room temperature, at least one liquid epoxy resin, and at least one amine curing agent.

[0071] The polymer containing silane groups is preferably an organic polymer containing silane groups, more particularly a polyolefin, a poly(meth)acrylate or a polyether, or a mixture of these polymers, each having one or preferably two or more silane groups. The silane groups may be present as side chains or at the ends of the chains.

[0072] In particular, the polymer containing silane groups is a polyether containing silane groups, which preferably has a majority of oxyalkylene units, in particular 1,2-oxypropylene units.

[0073] The polymer containing silane groups preferably has an average of 1.3 to 4, more preferably 1.5 to 3, particularly 1.7 to 2.8, and most preferably 1.7 to 2.3 silane groups per molecule. The silane groups are preferably terminal.

[0074] Preferred silane groups are trimethoxysilane, dimethoxymethylsilane or triethoxysilane groups.

[0075] The polymer containing silane groups preferably has an average molecular weight M in the range of 2,000 to 20,000 g / mol, more preferably 3,000 to 15,000 g / mol, in particular 4,000 to 10,000 g / mol. n has.

[0076] The polymer containing silane groups preferably has an average silicon content in the range of 0.3% to 2% by weight, in particular 0.5% to 1.5% by weight.

[0077] The polymer containing silane groups is preferably a polyether containing silane groups obtained by one of the following methods: reaction of polyethers containing allyl groups with hydrosilanes (hydrosilylation), optionally with chain extension, for example with diisocyanates; Copolymerization of alkylene oxides with epoxy silanes, optionally with chain extension, for example with diisocyanates, Reaction of polyether polyols with isocyanatosilanes, optionally with chain extension by diisocyanates, Reaction of polyether polyols with diisocyanates to give polyethers containing isocyanate groups, followed by reaction of the isocyanate groups with aminosilanes, hydroxysilanes or mercaptosilanes.

[0078] Preferably, the polymer containing silane groups results from the reaction of at least one polyether containing isocyanate groups with at least one aminosilane, mercaptosilane or hydroxysilane, which allows a particularly high adhesive strength of the adhesive.

[0079] The polyethers containing isocyanate groups preferably result from the reaction of at least one polyether polyol with at least one diisocyanate.

[0080] The reaction is preferably carried out with the exclusion of moisture at a temperature in the range of from 20 to 160° C., in particular from 40 to 140° C., optionally in the presence of a suitable catalyst.

[0081] The NCO / OH molar ratio is preferably at least 1.3 / 1, more preferably at least 1.6 / 1 and in particular at least 1.9 / 1.

[0082] Preferred polyether polyols are polyoxypropylene diols or polyoxypropylene triols, optionally having terminal oxyethylene groups.

[0083] Polyoxypropylene diols are particularly preferred.

[0084] Preferred diisocyanates are hexane 1,6-diisocyanate (HDI), 2,2(4),4-trimethylhexamethylene 1,6-diisocyanate (TMDI), cyclohexane 1,3-diisocyanate, cyclohexane 1,4-diisocyanate, isophorone diisocyanate (IPDI), perhydro(diphenylmethane diisocyanate) (H 12 MDI), 1,3-bis(isocyanatomethyl)cyclohexane, 1,4-bis(isocyanatomethyl)cyclohexane, xylene diisocyanate (XDI), diphenylmethane diisocyanate (MDI), toluene diisocyanate (TDI), phenylene diisocyanate (PDI), or naphthalene diisocyanate (NDI).

[0085] Particular preference is given to HDI, IPDI, MDI or TDI, in particular IPDI or MDI, or mixtures of these diisocyanates.

[0086] Aminosilanes suitable for reaction with isocyanate groups are primary or secondary aminosilanes. Adducts formed from primary aminosilanes such as 3-aminopropyltrimethoxysilane, 3-aminopropyldimethoxymethylsilane, 4-aminobutyltrimethoxysilane, 4-amino-3-methylbutyltrimethoxysilane, 4-amino-3,3-dimethylbutyltrimethoxysilane, N-butyl-3-aminopropyltrimethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, 3-aminopropyltrimethoxysilane or 3-aminopropyldimethoxymethylsilane, and Michael acceptors such as acrylonitrile, (meth)acrylic acid esters, (meth)acrylamides, maleic acid diesters, fumaric acid diesters, citraconic acid diesters or itaconic acid diesters, in particular N-(3-trimethoxysilylpropyl)diethylaminosuccinate or N-(3-dimethoxymethylsilylpropyl)diethylaminosuccinate are preferred. Likewise suitable are analogues of the aminosilanes mentioned which have ethoxy groups instead of methoxy groups on the silicon.

[0087] Particularly preferred are diethyl N-(3-trimethoxysilylpropyl)aminosuccinate, diethyl N-(3-dimethoxymethylsilylpropyl)aminosuccinate, or diethyl N-(3-triethoxysilylpropyl)aminosuccinate, which are readily available and provide particularly high strength and stability of the adhesive.

[0088] Suitable mercaptosilanes for reaction with isocyanate groups are in particular 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyldimethoxymethylsilane, or analogues of these mercaptosilanes which have ethoxy groups instead of the methoxy groups on the silicon.

[0089] Suitable hydroxysilanes for reaction with isocyanate groups are in particular N-(3-triethoxysilylpropyl)-2-hydroxypropanamide, N-(3-trimethoxysilylpropyl)-2-hydroxypropanamide, N-(3-triethoxysilylpropyl)-4-hydroxypentanamide, N-(3-triethoxysilylpropyl)-4-hydroxyoctanamide, N-(3-triethoxysilylpropyl)-5-hydroxydecanamide, N-(3-triethoxysilylpropyl)-2-hydroxypropyl carbamate, 2-morpholino-4(5)-(2-trimethoxysilylethyl)cyclohexan-1-ol, 2-morpholino-4(5)-(2-triethoxysilylethyl)cyclohexan-1-ol or 1-morpholino-3-(3-(triethoxysilyl)propoxy)propan-2-ol.

[0090] More preferably, the aminosilane, mercaptosilane, or hydroxysilane for reaction with polyethers containing isocyanate groups is an aminosilane, in particular diethyl N-(3-trimethoxysilylpropyl)aminosuccinate, diethyl N-(3-dimethoxymethylsilylpropyl)aminosuccinate, or diethyl N-(3-triethoxysilylpropyl)aminosuccinate.

[0091] Preferred polymers containing silane groups are particularly compatible with liquid epoxy resins, enabling adhesives with high strength, high impact resistance, and high stability against moisture.

[0092] The adhesive further comprises at least one liquid epoxy resin.

[0093] Suitable liquid epoxy resins are the usual industrial epoxy resins which are free-flowing at room temperature and have a glass transition temperature of less than 25° C. They are obtainable by known methods, more particularly by glycidylation of compounds which in particular have at least two active hydrogen atoms, more particularly polyphenols, polyols or amines, by reaction with epichlorohydrin.

[0094] Aromatic liquid epoxy resins, particularly bisphenol A diglycidyl ether, bisphenol F diglycidyl ether, or phenol novolac glycidyl ether, are preferred, as they have an easily controllable viscosity and provide adhesives with high strength and stability.

[0095] Preferably, the weight ratio of the silane group-containing polymer to the liquid epoxy resin in the adhesive is within the range of 20 / 80 to 70 / 30, preferably 25 / 75 to 50 / 50. Such an adhesive has high strength in addition to high impact resistance.

[0096] The adhesive also includes at least one amine curing agent capable of curing the liquid epoxy resin.

[0097] Suitable amine hardeners are amines having at least two, preferably at least three, amine hydrogens reactive with epoxy groups. Conventional polyamines having aliphatic amino groups and at least three amine hydrogens are preferred.

[0098] Suitable amine curing agents are also amines having at least two amine hydrogens and at least one silane group, particularly aminosilanes such as 3-aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, N-(2-aminoethyl)-N'-[3-(trimethoxysilyl)propyl]ethylenediamine, and analogs thereof having ethoxy groups in place of the methoxy groups on the silicon.

[0099] Suitable amine hardeners are also Mannich bases which catalyze the homopolymerization of epoxy resins, such as, inter alia, 2,4,6-tris(dimethylaminomethyl)phenol.

[0100] Preferably, the amine curing agent is selected from the group consisting of 1,5-diamino-2-methylpentane, 2,2(4),4-trimethylhexamethylenediamine, 1,2-diaminocyclohexane, 1,3-diaminocyclohexane, 1,4-diaminocyclohexane, 1,3-bis(aminomethyl)cyclohexane, 1,4-bis(aminomethyl)cyclohexane, 1-amino-3-aminomethyl-3,5,5-trimethylcyclohexane (IPDA), 2(4)-methyl-1,3-diaminocyclohexane, bis(4-aminocyclohexyl)methane, 2,5(2,6)-bis(aminomethyl)bicyclo[2.2.1]heptane, 1,3-bis(aminomethyl)benzene (MXDA), and 1,3-bis(aminomethyl)benzene (MXDA), having an average molecular weight M in the range of 200 to 500 g / mol. n and combinations of these amines.

[0101] Preferably, the adhesive contains at least one aminosilane.

[0102] Preferably, the adhesive comprises at least one polyamine having an aliphatic amino group and at least three amine hydrogens, in particular an average molecular weight M in the range of 200 to 500 g / mol. n or 1,2-diaminocyclohexane or IPDA or polyoxypropylene diamine, or a combination of these polyamines.

[0103] The adhesive preferably also contains 2,4,6-tris(dimethylaminomethyl)phenol.

[0104] The adhesive is preferably used as a two-component adhesive, where the two components are packaged separately and mixed prior to application.

[0105] The first component contains the amine hardener and other compounds that react with epoxy groups, the second component contains the liquid epoxy resin and other compounds that contain epoxy groups, and the polymer containing silane groups is a component of the first and / or second component, preferably the polymer containing silane groups is a component of the first component.

[0106] The two components are themselves storage stable with the exclusion of moisture. When the two components are mixed, the primary and / or secondary amino groups react with the epoxy groups present, and the silane groups react on contact with water to release alcohol.

[0107] The adhesive preferably contains further components, in particular components selected from the group consisting of reactive diluents containing epoxy groups, drying agents, accelerators, water and fillers.

[0108] Suitable reactive diluents containing epoxy groups are in particular butanediol diglycidyl ether, hexanediol diglycidyl ether, cresyl glycidyl ether, 4-methoxyphenyl glycidyl ether, p-tert-butylphenyl glycidyl ether, 4-nonylphenyl glycidyl ether, cardanol glycidyl ether, benzyl glycidyl ether, 2-ethylhexyl glycidyl ether or glycidyl ethers of natural alcohols, such as, in particular, C8-C 10 Or C 12 ~C 14 Or C 13 ~C 15 Such reactive diluents are preferably constituents of the second component.

[0109] Suitable desiccants are, in particular, tetraethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, organosilanes having a functional group in the α-position of the silane group, in particular N-(methyldimethoxysilylmethyl)-O-methylcarbamate or (methacryloyloxymethyl)silane, methoxymethylsilane, orthoformic acid esters, but also calcium oxide or molecular sieves. The desiccants are preferably constituents of the composition comprising the polymer containing silane groups.

[0110] Suitable accelerators are substances which accelerate the crosslinking of polymers which contain silane groups, in particular metal catalysts and / or nitrogen compounds.

[0111] Suitable metal catalysts are compounds of titanium, zirconium, aluminium or tin, in particular organotin compounds, organotitanates, organozirconates or organoaluminates, in particular dibutyltin dilaurate, dibutyltin diacetylacetonate or dioctyltin dilaurate.

[0112] Suitable nitrogen compounds are in particular the amine hardeners mentioned, and also amidines or guanidines.

[0113] Suitable accelerators are also substances which accelerate the reaction of epoxy groups, in particular acids such as salicylic acid or p-toluenesulfonic acid, or nitrates, in particular calcium nitrate, or tertiary amines, phenols or Mannich bases, or compounds having a mercapto group.

[0114] The adhesive preferably contains water or a water releasing substance, so that only a portion, if any, of the water required for crosslinking of the silane groups must be taken up from the environment.

[0115] The adhesive preferably contains up to 5% by weight, especially up to 2% by weight, of water, based on the total adhesive.

[0116] The free water is preferably not present in the same component as the polymer containing silane groups.

[0117] Suitable fillers are in particular ground or precipitated calcium carbonate, optionally coated with fatty acids, in particular stearates, barytes, quartz flour, silica sand, dolomite, wollastonite, calcined kaolin, layered silicates such as mica or talc, zeolites, aluminium hydroxide, magnesium hydroxide, silica, fine silica from pyrolysis processes, cement, gypsum, fly ash, industrially produced carbon black, graphite, metal powders such as aluminium, copper, iron, silver, steel, PVC powder or light-weight filling beads such as hollow glass or gas-filled hollow plastic beads (particulates).

[0118] Preferred fillers are calcium carbonate, calcined kaolin, fine silica, industrial carbon black, or combinations thereof.

[0119] The adhesives may contain further additives, such as in particular plasticizers such as phthalates, hydrogenated phthalates, terephthalates, hydrogenated terephthalates, polyether polyols or other substances known as plasticizers, further crosslinkers such as epoxy silanes or mercaptosilanes, solvents or thinners, pigments, dyes, thickeners, fibers, nanofillers, flame retardants, emulsifiers, wetting agents, defoamers or stabilizers against oxidation, heat, light or UV light.

[0120] The adhesive preferably comprises, based on the total adhesive: 10% to 40% by weight of a polymer containing silane groups, 20% to 60% by weight of liquid epoxy resin, 0% to 25% by weight of an epoxy group-containing reactive diluent, 5% to 30% by weight of an amine hardener, 0% to 50% by weight of filler, and optionally further ingredients.

[0121] The adhesive is preferably used as a two-component adhesive. The first and second components are prepared separately and stored in a moisture-proof container. Suitable containers are, inter alia, drums, hobbocks, buckets, cans, cartridges, aluminized foil pouches or tubes.

[0122] The two components are mixed before or during application of the adhesive. The mixing ratio is preferably selected so that the groups reactive to epoxy groups are present in the appropriate ratio relative to the epoxy groups. The ratio of the number of amine hydrogens to the number of epoxy groups is preferably in the range of 0.5 to 1.5, in particular 0.8 to 1.2. The mixing ratio in parts by weight is typically in the range of 1:10 to 10:1.

[0123] When the two components are mixed, hardening by chemical reactions begins: here, the epoxy groups react with the amine hydrogens and the silane groups undergo hydrolysis with the release of alcohol to form silanol groups (Si-OH groups) and, through a subsequent condensation reaction, siloxane groups (Si-O-Si groups). As a result of these reactions, and possibly further reactions, the adhesive hardens. If water is not already present in the adhesive for the hydrolysis of the silane groups, water can penetrate into the adhesive from the wood or cementitious composition and / or in the form of moisture in the air.

[0124] The cured adhesive has very high strength, high elongation and high impact resistance, preferably with a tensile strength of at least 10 MPa, preferably at least 15 MPa, and an elongation at break of at least 10%, determined on dumbbell-shaped test specimens with a length of 75 mm, a bar length of 30 mm, a bar width of 4 mm and a thickness of about 2 mm according to DIN EN 53504 at a strain rate of 2 mm / min.

[0125] The liquid cementitious composition contains at least one cement.

[0126] Suitable cements are all available types of cement and mixtures of two or more types of cement. Examples of suitable cement types are those described in DIN EN 197-1, in particular Portland cement (CEM I), Portland composite cement (CEM II), blast furnace slag cement (CEM III), pozzolanic cement (CEM IV) or composite cement (CEM V). These main types are divided into subgroups that are well known to those skilled in the art. Also suitable are cement types produced according to alternative standards, such as, in particular, ASTM C150 for Portland cement or ASTM C595 for blended hydraulic cements.

[0127] Particularly preferred cements are CEM I Portland cements according to DIN EN 197-1, in particular Portland cement types I-42.5, I-42.5R or I-52.5, or Portland cements according to ASTM C150.

[0128] Further preferred cements are calcium aluminate or calcium sulfoaluminate cements, optionally in combination with calcium sulfate and / or Portland cement.

[0129] Portland cement is particularly preferred.

[0130] In addition to cement, the cementitious composition may contain so-called supplementary cementitious materials (SMCs). These are materials that, in finely divided form, can react with calcium hydroxide and water to give compounds with cement-like properties. Preferred SMCs are fly ash, slag, metakaolin, pozzolans, or silica fume.

[0131] Furthermore, the liquid cementitious composition may contain further inorganic substances capable of reacting with water, in particular calcium sulfate.

[0132] The liquid cementitious composition preferably contains at least one inorganic filler.

[0133] The inorganic filler is preferably selected from the group consisting of quartz flour, silica sand, sandy limestone, river sand, aggregate, calcium carbonate, chalk, barite, dolomite, wollastonite, talc, titanium dioxide, and combinations thereof.

[0134] The cementitious composition preferably contains a mixture of two or more inorganic fillers.

[0135] Quartz powder, silica sand, aggregate, calcium carbonate, chalk, or mixtures thereof are particularly preferred.

[0136] The liquid cementitious composition preferably further contains water.

[0137] The amount of water is preferably such that the composition is in the form of a pasty, free-flowing mass that can be poured and spread without excessive runoff. The amount of water required to obtain such a consistency depends on the type of cement, the type and amount of inorganic filler, and especially the presence of further additives such as plasticizers.

[0138] The water-cement value (w / c) of the liquid cement-based composition is preferably in the range of 0.2 to 0.75, particularly 0.4 to 0.6, which allows the hardened composition to achieve high strength and impermeability.

[0139] The liquid cementitious composition preferably contains further additives customary in prior art cementitious compositions, in particular additives selected from the group consisting of accelerators, retarders, flow aids, thickeners, defoamers, water retention agents, pigments and biocides.

[0140] The liquid cementitious composition preferably contains at least one Portland cement, at least one inorganic filler, water, and optionally further additives.

[0141] More preferably, the liquid cementitious composition has, based on the entire liquid cementitious composition: 5-60% by weight of Portland cement, 20% to 80% by weight, preferably 30% to 70% by weight, of an inorganic filler, 3% to 30% by weight, preferably 5% to 20% by weight, of water, and 0% to 30% by weight, preferably 0.1% to 25% by weight of further additives Contains:

[0142] Cementitious compositions containing sand and little coarse aggregate are also called mortars. They contain, in particular, inorganic fillers with particle sizes in the range of 0.05 to 4 mm.

[0143] Cementitious compositions containing aggregates are also called concretes. They contain in particular a mixture of inorganic fillers with a particle size in the range of 0.05 to 4 mm and aggregates with a particle size of up to 32 mm, in particular up to 16 mm.

[0144] The solid or dry components of the cementitious composition are preferably mixed with water to obtain a liquid cementitious composition.

[0145] After the addition of water, hydraulic setting of the cement begins, resulting in the gradual hardening of the liquid cementitious composition to form a solid stone-like material, particularly hardened mortar or cement.

[0146] During the early stages of hardening, it may be advantageous to cover the cementitious composition with a polymer film to protect it from drying out, thus ensuring sufficient water for the hydraulic hardening of the cement.

[0147] The present invention further provides a laminate obtainable from the process of the present invention.

[0148] The laminate comprises a wood layer and a hydraulically hardened layer of a cementitious composition bonded together in a press fit manner via an adhesive.

[0149] The laminate preferably has a rectangular parallelepiped shape. [Brief description of the drawings]

[0150] [Figure 1] Figure 1 shows, by way of example, the laminate described, which comprises a wood layer (H), an adhesive layer (K) and a layer of cementitious composition (Z). DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0151] The bottom surface of the rectangular parallelepiped is preferably formed by a wooden surface, and the top surface of the rectangular parallelepiped is preferably formed by a cementitious composition. The thickness of the wooden layer is preferably equal to or greater than the thickness of the cementitious layer. FIG. 1 shows, by way of example, the thickness (D H ), thickness of adhesive layer (K) (D K ), and the thickness (D Z ) is shown.

[0152] The dimensions of the laminate are preferably such that, in the absence of support, reinforcement or reinforcement, the wood layer can support the layer of cementitious composition without bending significantly under its weight.

[0153] The laminates are stable and durable. They can in particular be transported freely in space without permanently bending. They can be stacked and their stability is not significantly impaired even when exposed to heat, moisture or ultraviolet light.

[0154] The laminates are also called plates, beams, bars or sandwich elements.

[0155] The invention further provides for the use of the laminate as a component in a building construction, in particular as a roofing element, which is in particular installed as a roofing element, with the wooden side forming the ceiling visible from the inside and the side of the cementitious composition facing the roof or upper floor.

[0156] The laminate according to the method of the invention allows the installation of load-bearing wooden ceilings which are particularly sound- and thermally insulating, stable, require low levels of hydraulic binders and admixtures and are therefore particularly sustainable. EXAMPLES

[0157] The following examples are given with the aim of further illustrating the invention as described, but it will be appreciated that the invention is not limited to these described examples.

[0158] "Standard Climatic Conditions" ("SCC") refers to a temperature of 23±1°C and a relative humidity of 50±5%.

[0159] The square-bar laminated beech wood used was manufactured by Fagus Suisse SA.

[0160] Adhesive manufacturing: Adhesive S1: A first component was prepared by mixing the following components in the specified amounts (parts by weight, PW) using a centrifugal mixer (SpeedMixer™ DAC150, FlackTek Inc.) and storing the mixture with the exclusion of moisture: A linear polymer of 61.6 PW containing silane groups with terminal trimethoxysilane groups, a polyether backbone and a silicon content of 0.91 wt. %. 1.7PW vinyltrimethoxysilane, 1,2-diaminocyclohexane at 22.8 PW (Dytek® DCH-99, Invista, AHEW 28.5 g / eq); 7.5 PW polyoxypropylene diamine (Jeffamin® D-400, Huntsman, AHEW 115 g / eq), 2.65 PW of 3-aminopropyltrimethoxysilane (Silquest® A-1110, Momentive, AHEW 89.7 g / eq); 1.8 PW diisodecyl phthalate (Palatinol® 10-P, manufactured by BASF); 1.95PW catalyst and UV stabilizer.

[0161] Similarly, a second component was prepared by mixing the following ingredients and storing the mixture in the absence of moisture: Bisphenol A diglycidyl ether of 66.4 PW (Araldite® GY250, Huntsman, EEW 187 g / eq), 22.1 PW hexanediol diglycidyl ether (Araldite® DY-H, Huntsman, EEW 149 g / eq), 2.5PW emulsifier mixture, 1.4PW carbon black, 7.6PW filler.

[0162] For application, the two components were mixed in a mix ratio of 0.6 / 1 parts by weight of first component to second component and processed using a centrifugal mixer or another suitable mixing system to obtain a homogenous liquid adhesive mixture that was applied within 10 minutes.

[0163] To evaluate the adhesive properties, the following tests were performed: The mixed viscosity was measured 5 minutes after mixing the two components at a temperature of 20°C and at a shear rate of 10 s -1 was measured using a thermostated Rheotec RC30 cone-plate viscometer (cone diameter 50 mm, cone angle 1°, cone-tip-plate distance 0.05 mm).

[0164] For pot life measurements, 300 g of freshly mixed adhesive was stirred with a spatula in a 500 ml beaker at 5 minute intervals until the adhesive thickened to the point where it no longer had good workability.

[0165] To determine the mechanical properties, the mixed adhesive was poured onto a PTFE-coated film to obtain a film with a thickness of 2 mm and stored under standard climatic conditions. After 1 day, dumbbell-shaped test specimens with a length of 75 mm, bar length of 30 mm and bar width of 4 mm were punched out of the film and stored under standard climatic conditions for a further 6 days. Subsequently, at a strain rate of 2 mm / min, the tensile strength (breaking force), the elongation at break and the modulus of elasticity at 0.05% to 0.25% elongation (MoE 0.25%) were determined as described in DIN EN 53504.

[0166] Adhesive S1 had a mixed viscosity of 7.75 Pa s, a pot life of 35 min, a tensile strength of 20 MPa, an elongation at break of 15%, and a 0.25% modulus of 779 MPa. Upon curing, a non-tacky, homogeneous, blister-free material with a silky matte surface and high tensile strength and impact resistance was obtained.

[0167] In adhesive S1, the weight ratio of the polymer containing silane groups to the diglycidyl ether of bisphenol A is 35.7 / 64.3.

[0168] Laminate manufacturing: Example 1: Several laminates were produced under standard climatic conditions, in each case a 40x50x30 mm piece of wood made of beech was placed on a horizontal substrate with an area of ​​40x50 mm facing up and a thickness of 30 mm. Surface dust was removed with a brush. 3 g of mixed adhesive S1 was then applied to the clean surface and spread evenly with a spatula (application rate 1.5 kg / m2). 2 (equivalent to).

[0169] The test specimen thus coated was clamped into a mould which seamlessly surrounded the outside of the timber and extended 30 mm beyond the surface of the timber to form a 30 mm deep cast of the cementitious composition.

[0170] Freshly made mortar (SikaGrout®-212N, from Sika Schweiz AG, made with 2.9 l water for 25 kg dry mortar) was then introduced in a layer thickness of 30 mm into the mould and thus onto the surface of the wood coated with S1. The waiting time after mixing of the adhesive and pouring of the mortar was 20-30 min. At the time of applying the mortar, the adhesive had not yet formed a skin (the adhesive stuck to the pipette when tapped with an LDPE pipette).

[0171] The specimens thus produced were left under standard climatic conditions for 48 hours, after which the formwork moulds were removed, resulting in a laminate of 40x50x60 mm consisting of beech wood with dimensions 40x50x30 mm and hardened mortar with dimensions 40x50x30 mm, with the wood and mortar firmly bonded together by adhesive S1 over an area of ​​40x50 mm.

[0172] A number of such test specimens were stored under standard climatic conditions for 28 days and then subjected to a compressive shear strength test, which was determined in accordance with DIN EN 392 on a bonded shear area of ​​50 x 40 mm at a test speed of 1 mm / s.

[0173] Further specimens of this type were stored under standard climatic conditions for 28 days and then stored in water at room temperature for 24 hours and then subjected to the compressive shear strength test described above, also in the wet state.

[0174] Example 1 showed a compressive shear strength of 3.9 MPa (average of 6 specimens) after 28 days of storage under standard climatic conditions, with spalling in the mortar layer close to the adhesive in all cases.

[0175] After 24 hours of storage in water, the wood layer had visibly swelled in all cases (increased in volume by approximately 30%) but the specimens were otherwise intact. The compressive shear strength of the wet specimens was 2.0 MPa (average of six specimens) and in all cases there was spalling in the mortar layer close to the adhesive.

[0176] Example 2: Several laminates were produced under standard climatic conditions, in each case a piece of wood made of beech, measuring 1020 x 60 x 30 mm, was placed on a horizontal substrate with an area of ​​1020 x 60 mm facing up and a thickness of 30 mm. Surface dust was removed with a brush. Then 1.5 kg / m2 of mixed adhesive S1 was applied to the clean surface. 2 The test piece was then fixed in a mold to obtain a mold 30 mm deep.

[0177] 30 minutes after application of the adhesive, freshly prepared mortar (SikaGrout®-212N, manufactured by Sika Schweiz AG, prepared with 2.9 l of water for 25 kg of dry mortar) was introduced into the mould in a layer thickness of 30 mm and thus onto the surface of the wood coated with S1.

[0178] The specimens were left under standard climatic conditions for 48 hours, after which the formwork moulds were removed. As a result, a laminate of 1020x60x60mm was obtained, consisting of beech wood with dimensions 1020x60x30mm and hardened mortar with dimensions 1020x60x30mm, with the wood and mortar firmly bonded together over an area of ​​1020x60mm by adhesive S1.

[0179] A number of such specimens were stored under standard climatic conditions for 28 days and subjected to a three-point bending test according to DIN 512186 with a span width of 900 mm, an initial load of 5 N and a test speed of 5 mm / min. To measure the elastic modulus, such specimens were subjected to the same test, where the test speed was 2 mm / min and the load range was 100-3200 N.

[0180] Example 2 showed a maximum force of 1.2 kN and a maximum deformation of 14 mm (average of four specimens) in a three-point bending test, with spalling in the mortar layer close to the adhesive in all cases (by comparison, uncoated beech specimens with dimensions 1020 x 60 x 60 mm in the same test configuration showed a maximum force of 1.8 kN and a maximum deformation of 28 mm).

[0181] Example 2 exhibited a modulus of elasticity of 14.8 MPa (average of 5 specimens) in a 3-point bending test (by comparison, uncoated beech specimens of dimensions 1020 x 60 x 60 mm in the same test configuration exhibited a modulus of elasticity of 13.4 MPa).

[0182] Example 3: Several stacks were produced under standard climatic conditions by placing a square-bar laminated wooden beam of dimensions 5200 x 320 x 120 mm, made of glued beech squares (approximately 2000 x 40 x 40 mm), on a horizontal base with the 5200 x 320 mm area facing up and a thickness of 120 mm. A formwork mould was attached around the wooden beam so that a mould 60 mm deep was formed on the surface.

[0183] Next, the surface of the wooden beam (= the bottom of the mold) was blown to remove dust, and then blown with 1.5 kg / m 2 The mixed adhesive S1 was coated by pouring and spreading using a spatula.

[0184] Reinforcement in the form of architectural steel mesh was then placed over the entire adhesive-coated surface, the mesh being restrained at a height of 25-35mm above the adhesive surface by spacers in the form of concrete blocks.

[0185] Freshly prepared self-compacting concrete (Sikacrete®-16SCC, manufactured by Sika Schweiz AG, prepared with 2.2 l of water for 25 kg of dry mix) was then poured into the mould to form the concrete into the reinforcement. The waiting time between mixing of the adhesive and pouring of the concrete was 20-30 min.

[0186] The arrangement thus produced was covered with a polymer film and left under standard climatic conditions for 48 hours, after which the polymer film and the formwork were removed. The laminate thus obtained was stored under standard climatic conditions for a further 26 days and was then ready for use as a roof element in a building structure. Its dimensions were 5200 x 320 x 180 mm and there was no distortion in length, width or height. In particular, no shrinkage cracks or warping due to shrinkage of the concrete layer, also called "keying", were observed, and no peeling of the concrete from the wooden surface after hardening was observed.

Claims

1. A method for manufacturing a laminate, comprising: (i) providing wood; (ii) coating the wood on its upper surface with an adhesive applied in liquid form, the adhesive comprising at least one polymer containing silane groups that is liquid at room temperature, at least one liquid epoxy resin, and at least one amine hardener; (iii) applying a liquid cementitious composition over the applied adhesive while still wet; and (iv) curing the liquid cementitious composition and the adhesive, respectively; A method for producing a laminate, comprising:

2. 2. The method according to claim 1, characterized in that the wood in step (i) consists of hard or soft wood, preferably beech or spruce, in particular beech.

3. 3. A method according to claim 1 or 2, characterized in that the wood has a thickness in the range of 10 to 300 mm, preferably 20 to 200 mm.

4. 3. The method of claim 1 or 2, characterized in that the wood is not primed before step (ii).

5. 3. The method according to claim 1 or 2, characterized in that the adhesive in step (ii) is applied in a layer thickness ranging from 0.1 to 10 mm, preferably from 0.2 to 7 mm, in particular from 0.3 to 5 mm.

6. 3. The method according to claim 1 or 2, characterized in that when applying the liquid cementitious composition in step (iii), the wood is provided with formwork elements on the outside, so that after the application the liquid cementitious composition remains on the surface of the wood and cannot flow out.

7. 3. The method according to claim 1 or 2, characterized in that the liquid cementitious composition in step (iii) is applied in a layer thickness in the range of 10 to 300 mm, preferably 20 to 200 mm, in particular 30 to 100 mm.

8. 3. The method of claim 1 or 2, characterized in that the hardening in step (iv) is carried out by leaving at ambient temperature, optionally with the use of a polymer film to protect the cementitious composition from drying at the surface.

9. 3. The method according to claim 1, wherein the polymer containing silane groups has an average silicon content in the range of 0.3 to 2% by weight.

10. 3. The method according to claim 1, wherein the polymer containing silane groups is obtained by reacting at least one polyether containing isocyanate groups with at least one aminosilane, mercaptosilane, or hydroxysilane.

11. 3. The method according to claim 1 or 2, characterized in that the weight ratio of the polymer containing silane groups to the liquid epoxy resin in the adhesive is in the range of 20 / 80 to 70 / 30, preferably 25 / 75 to 50 / 50.

12. The amine curing agent may be 1,5-diamino-2-methylpentane, 2,2(4),4-trimethylhexamethylenediamine, 1,2-diaminocyclohexane, 1,3-diaminocyclohexane, 1,4-diaminocyclohexane, 1,3-bis(aminomethyl)cyclohexane, 1,4-bis(aminomethyl)cyclohexane, 1-amino-3-aminomethyl-3,5,5-trimethylcyclohexane, 2(4)-methyl-1,3-diaminocyclohexane, bis(4-aminocyclohexyl)methane, 2,5(2,6)-bis(aminomethyl)bicyclo[2.2.1]heptane, 1,3-bis(aminomethyl)benzene, or an average molecular weight M in the range of 200 to 500 g / mol. ｎ Polyoxypropylene diamines and polyoxypropylene triamines having the formula (I), bis(hexamethylene)triamine, triethylenetetramine, tetraethylenepentamine, N,N'-bis(3-aminopropyl)ethylenediamine, N,N-dimethyldi(1,3-propylene)triamine, N-benzylethane-1,2-diamine, N-benzylpropane-1,2-diamine, N-benzyl-1,3-bis(aminomethyl)benzene, N-(2-phenylethyl)-1,3-bis(aminomethyl)benzene, 1,5-diamino-2-methylpentaamine, 3. The method according to claim 1, wherein the amine is selected from the group consisting of an adduct of propane-1,2-diamine or propane-1,2-diamine with cresyl glycidyl ether, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropyltriethoxysilane, 2,4,6-tris(dimethylaminomethyl)phenol, and combinations of these amines.

13. 3. The method according to claim 1 or 2, characterized in that the liquid cementitious composition contains at least one portland cement, at least one inorganic filler, water, and optionally further additives.

14. A laminate obtained from the method of claim 1 or 2.

15. 15. Use of a laminate according to claim 14 as a component in a building construction, in particular as a roof element.

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