Tertiary amines for improving creep behavior of chemical anchors

Abstract

The present invention relates to the use of a tertiary amine in an epoxy resin composition for improving the creep behavior of a chemical anchor made from the epoxy resin composition.

Description

Technical Field

[0001] The present invention relates to the use of tertiary amines in epoxy resin compositions for improving the creep behavior of chemical anchors produced from the epoxy resin compositions. Background Art

[0002] Multicomponent compositions based on curable epoxy resins and amines have been known for some time and are used as chemical anchors for fastening construction elements such as anchor rods, rebars and screws in drilled holes in various substrates such as concrete.

[0003] Chemical anchors tend to creep during the service life of the chemical anchor, especially under continuous load and elevated temperature. In this context, creep describes the plastic deformation or movement of the chemical anchor due to the impact of the continuous load. Creep significantly impairs the properties of the chemical anchor, as described, for example, in: R. Nilforoush; M. Nils; G. L. Elfgren; "Long-Term Performance of Adhesive Bonded Anchors", Structural Journal, 2016, 113(2), 251-261. The characterization of the creep of chemical anchors and the related specifications of the creep behavior play an important role in the durability and reliability of anchor points using chemical anchors in the construction industry. Therefore, when designing anchor points in the construction industry, specifications on creep behavior are used.

[0004] EP 1 716 195 B1 describes the use of tertiary amines in chemical anchoring systems. A relationship is assumed between the use of tertiary amines in the curing agent component of a multi-component composition and the increase in the maximum achievable glass transition temperature of a composition produced from the multi-component composition. However, epoxy-amine systems do not cure completely at temperatures below their maximum possible glass transition temperature. This applies in particular to systems that cure in thin layers, for example in an annular gap between concrete and anchor, which is approximately 1 mm and therefore cannot be heated exothermically. This has been investigated, inter alia, by Michel et al., Constr. Build. Mat., 2020, 231, 117206 and Kroutilova et al., J. Appl. Pol. Sci., 2006, 99, 3669. Since there is no maximum glass transition temperature of the system in the creep test (the creep test is usually carried out below the maximum glass transition temperature of the system), no influence on the creep behavior of the chemical anchor can be drawn from the specification of the final glass transition temperature. Therefore, no connection is known between the use of tertiary amines and the improved creep behavior of the chemical anchor.

[0005] In view of the above embodiments, it would be desirable to be able to provide chemical anchors, particularly epoxyamine based chemical anchors, having improved creep behavior. Summary of the invention

[0006] The object of the present invention is therefore to provide a simple and cost-effective solution with which the creep behavior of chemical anchors, in particular chemical anchors based on epoxyamines, can be improved. The object of the present invention is in particular to improve the creep behavior of chemical anchors based on epoxyamines at elevated temperatures, preferably between 40° C. and the glass transition temperature of the chemical anchor.

[0007] The object underlying the present invention is achieved by using at least one tertiary amine in an epoxy resin composition in an amount of ≥ 1.0 wt. %, based on the total weight of the epoxy resin composition according to claim 1. Preferred embodiments of the use according to the invention are provided in the dependent claims, which can optionally be combined with one another.

[0008] In the context of the present invention, the terms used above and in the following description have the following meanings:

[0009] "Creep behavior" describes the plastic deformation, displacement or movement of a chemical anchor due to the impact of a sustained load (continuous load).

[0010] "Amines" are compounds derived from ammonia by replacement of one, two or three hydrogen atoms with hydrocarbon radicals and having the general structures RNH2 (primary amines), R2NH (secondary amines) and R3N (tertiary amines) (see: IUPAC Compendium of Chemical Terminology, 2nd edition ("Gold Book"), edited by AD McNaught and A. Wilkinson, Blackwell Scientific Publications, Oxford (1997)).

[0011] Surprisingly, it has now been found that the use of at least one tertiary amine in a weight percentage of ≥1.0 wt. %, based on the total weight of the epoxy resin composition, leads to a significant improvement in the creep behavior of the chemical anchor produced from the epoxy resin composition.

[0012] The epoxy resin composition is preferably a multi-component epoxy resin composition, preferably a two-component epoxy resin composition, which comprises an epoxy resin component (A) and a curing agent component (B). The epoxy resin component (A) comprises at least one curable epoxy resin. The curing agent component (B) comprises at least one amine that reacts with epoxy groups. In the multi-component epoxy resin composition, the epoxy resin component (A) and the curing agent component (B) are separated from each other in a manner that inhibits the reaction.

[0013] In order to improve the creep behavior of the chemical anchor, it is essential for the present invention to use ≥1.0% by weight of at least one tertiary amine in the epoxy resin composition, based on the total weight of the epoxy resin composition.

[0014] Tertiary amines are preferably used in the curing agent component (B) of the multi-component epoxy resin composition. Based on the total weight of the curing agent component (B), the curing agent component (B) preferably contains ≥5.0 wt. %, preferably 5.0 wt. % to 20 wt. % of tertiary amine. In a preferred embodiment of the present invention, the curing agent component (B) contains 5.0 wt. % to 10.0 wt. % of tertiary amine, based on the total weight of the curing agent component (B).

[0015] The epoxy resin composition is used for the manufacture of chemical anchors which are generally used for construction purposes. The expression "for construction purposes" refers to the structural bonding of concrete / concrete, steel / concrete or steel / steel or one of these materials to other mineral materials, the reinforcement of structures with components made of concrete, brickwork and other mineral materials, the reinforcement of applications with fiber-reinforced polymers of construction items, the chemical fastening of surfaces made of concrete, steel or other mineral materials, in particular the chemical fastening of construction elements and anchoring members (such as anchor rods, anchor bolts, (threaded) rods, (threaded) sleeves, reinforcement bars, screws etc.) in drilled holes in various substrates such as (reinforced) concrete, brickwork, other mineral materials, metals (e.g. steel), ceramics, plastics, glass and wood.

[0016] The tertiary amine for use according to the invention preferably comprises at least three tertiary amino groups. The tertiary amine for use according to the invention preferably comprises a 6-membered ring. In a preferred embodiment, the tertiary amine comprises at least three tertiary amino groups and a 6-membered ring, preferably a 6-membered aromatic ring.

[0017] In a preferred embodiment, the tertiary amine is selected from the group of tertiary aminophenols, preferably from the group of 2,4,6-tris(di-C1-C6-alkylamino)phenols.

[0018] The tertiary amine is particularly preferably selected from the group consisting of: 2,4,6-tris(dimethylaminomethyl)phenol (trade name K54) and 1,3,5-tris[3-(dimethylamino)propyl]hexahydro-1,3,5-triazine (available under the trade name N600 is commercially available).

[0019] In a particularly preferred embodiment, 2,4,6-tris(dimethylaminomethyl)phenol is used for the use according to the invention for improving the creep behavior of chemical anchors.

[0020] The curing agent component (B) comprises at least one amine reactive with epoxy groups. The corresponding amines are known to those skilled in the art. Preferably, the at least one amine reactive with epoxy groups is selected from the group consisting of aliphatic, alicyclic, aromatic and araliphatic amines and has an average of at least two reactive hydrogen atoms bonded to nitrogen atoms per molecule.

[0021] Examples of amines reactive with epoxy groups are described below, but do not limit the scope of the present invention in any way: 1,2-diaminoethane (ethylenediamine), 1,2-propylenediamine, 1,3-propylenediamine, 1,4-diaminobutane, 2,2-dimethyl-1,3-propylenediamine (neopentyldiamine), diethylaminopropylamine (DEAPA), 2-methyl-1,5-diaminopentane, 1,3-diaminopentane, 2,2,4- or 2,4,4-trimethyl-1,6-diaminohexane and mixtures thereof (TMD), 1,3 ... (Aminomethyl)-cyclohexane, 1,2-bis(aminomethyl)cyclohexane, hexamethylenediamine (HMD), 1,2- and 1,4-diaminocyclohexane (1,2-DACH and 1,4-DACH), bis(4-amino-3-methylcyclohexyl)methane, diethylenetriamine (DETA), 4-azaheptane-1,7-diamine, 1,11-diamino-3,6,9-trioxaundecane, 1,8-diamino-3,6-dioxaoctane, 1,5-diamino-methyl-3-azapentane, 1,10-diamino- Amino-4,7-dioxadecane, bis(3-aminopropyl)amine, 1,13-diamino-4,7,10-trioxatridecane, 4-aminomethyl-1,8-diaminooctane, 2-butyl-2-ethyl-1,5-diaminopentane, N,N-bis(3-aminopropyl)methylamine, triethylenetetramine (TETA), tetraethylenepentamine (TEPA), pentaethylenehexamine (PEHA), 1,3-phenylenediamine (m-xylenediamine, MXDA), 1,4-phenylenediamine (p-xylenediamine, PX DA), 5-(aminomethyl)bicyclo[[2.2.1]hept-2-yl]methanamine (NBDA, norbornane diamine), dimethyldipropylenetriamine, dimethylaminopropylaminopropylamine (DMAPAPA), 3-aminomethyl-3,5,5-trimethylcyclohexylamine (isophorone diamine (IPDA)), diaminodicyclohexylmethane (PACM), diethylmethylphenylenediamine (DETDA), 4,4'-diaminodiphenyl sulfone (dapsone sulfone), mixed polycyclic amines (MPCA) (e.g. Ancamine 2168), dimethyldiaminodicyclohexylmethane (Laromin C260), 2,2-bis(4-aminocyclohexyl)propane, (3(4),8(9)bis(aminomethylbicyclo[5.2.1.0 2,6 ]decane (mixture of isomers, tricyclic primary amine; TCD-diamine), methylcyclohexyldiamine (MCDA), N,N'-diaminopropyl-2-methylcyclohexane-1,3-diamine, N,N'-diaminopropyl-4-methylcyclohexane-1,3-diamine, N-(3-aminopropyl)cyclohexylamine and 2-(2,2,6,6-tetramethylpiperidin-4-yl)propane-1,3-diamine.

[0022] Preferred amines are polyamines, such as 2-methylpentanediamine ( A), 3-aminomethyl-3,5,5-trimethylcyclohexane (IPDA), 1,3-phenylenediamine (m-phenylenediamine, MXDA), 1,4-phenylenediamine (p-phenylenediamine, PXDA), 1,6-diamino-2,2,4-trimethylhexane (TMD), diethylenetriamine (DETA), triethylenetetramine (TETA), tetraethylenepentamine (TEPA), pentaethylenehexamine (PEHA), N-ethylaminopiperazine (N-EAP), (3(4),8(9)bis(aminomethyl)bicyclo[5.2.1.0 2,6 ] decane (mixture of isomers, tricyclic primary amine; TCD-diamine), 1,14-diamino-4,11-dioxatetradecane, dipropylenetriamine, 2-methyl-1,5-pentanediamine, N,N'-dicyclohexyl-1,6-hexanediamine, N,N'-dimethyl-1,3-diaminopropane, N,N'-diethyl-1,3-diaminopropane, N,N'-dimethyl-1,3-diaminopropane, secondary polyoxypropylenediamine and triamine, 2,5-diamino-2,5-dimethylhexane, bis(amino-methyl)tricyclopentadiene, 1,8-diamino-p-menthane, bis(4-amino-3,5-dimethylcyclohexyl)methane, 1,3-bis(aminomethyl)cyclohexane (1,3-BAC), dipentylamine, N-2-(aminoethyl)piperazine (N-AEP), N-3-(aminopropyl)piperazine, piperazine, and methylcyclohexyldiamine (MCDA).

[0023] The amines may be used alone or as a mixture of two or more of the specified amines.

[0024] The amines reactive with epoxy groups are preferably contained in the hardener component (B) in a proportion of 10% to 90% by weight, particularly preferably 35% to 60% by weight, based on the total weight of the hardener component (B).

[0025] The curing agent component (B) preferably comprises a salt (S) selected from the group consisting of nitrates, halogen salts, trifluoromethanesulfonates and combinations thereof. The following compounds are particularly suitable as salts (S): Ca(NO3)2 (calcium nitrate, usually used as Ca(NO3)2 tetrahydrate), a mixture of Ca(NO3)2 / HNO3, KNO3 (potassium nitrate), NaNO3 (sodium nitrate), Mg(NO3)2 (magnesium nitrate, usually used as Mg(NO3)2 hexahydrate), Al(NO3)3 (aluminum nitrate, usually used as Al(NO3)3 nonahydrate), NH4NO3 (ammonium nitrate), Ca(NO2)2 (calcium nitrite), NaCl (sodium chloride), NaBr (sodium bromide), NaI (sodium iodide), Ca(CF3SO3)2 (calcium trifluoromethanesulfonate), Mg(CF3SO3)2 (magnesium trifluoromethanesulfonate), Li(CF3SO3)2 (lithium trifluoromethanesulfonate). The salts can be used alone or as a mixture of two or more of the specific salts. The salt (S) is preferably contained in the curing agent component (B) in a proportion of 0.1% to 15% by weight, preferably in a proportion of 1.0% to 10.0% by weight, based on the total weight of the curing agent component (B).

[0026] In order to improve the solubility properties of the salt (S) in the curing agent component (B), the salt (S) can be dissolved in a suitable solvent and used accordingly as a solution. Organic solvents such as methanol, ethanol and glycerol are suitable for this purpose.

[0027] The curing agent component (B) may comprise further additives from the following group: solvents, further phenolic accelerators, co-accelerators, adhesion promoters and inorganic fillers.

[0028] Based on the total weight of the curing agent component (B), a non-reactive diluent (solvent) may preferably be contained in an amount of up to 30% by weight, for example 1% to 20% by weight. Examples of suitable solvents are alcohols such as methanol, ethanol or diols, lower alkyl ketones such as acetone, di-lower alkyl lower alkanoyl amides such as dimethylacetamide, lower alkyl benzenes such as xylene or toluene, phthalates or paraffins. Based on the total weight of the curing agent component (B), the amount of solvent is preferably <5% by weight.

[0029] The phenolic accelerators are preferably selected from salicylic acid, styrenated phenols and cardanol and mixtures thereof. These may be present in the curing agent component (B) in a proportion of 0% to 10% by weight, based on the total weight of the curing agent component.

[0030] For example, benzyl alcohol, novolac resin, imidazole, organic phosphine, toluenesulfonic acid, Lewis base or acid (such as phosphoric acid ester) or a mixture of two or more thereof can be used as the co-accelerator. The co-accelerator is preferably contained in the curing agent component (B) in a weight proportion of 0.001 wt % to 5 wt %, based on the total weight of the curing agent component (B).

[0031] By using an adhesion promoter, the crosslinking of the borehole wall with the mortar mass is improved, so that adhesion is increased in the hardened state. Suitable adhesion promoters are selected from the group consisting of silanes having at least one Si-bonded hydrolyzable group, such as 3-glycidyloxypropyltrimethoxysilane, 3-glycidyloxypropyltriethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, N-2-(aminoethyl)-3-aminopropylmethyl-diethoxysilane, N-2-(aminoethyl)-3-aminopropyl-triethoxysilane, 3-aminopropyl-trimethoxysilane, 3-aminopropyltriethoxysilane, N-phenyl-3-aminoethyl-3-aminopropyl-trimethoxysilane, 3-mercaptopropyltrimethoxysilane and 3-mercaptopropylmethyldimethoxysilane. 3-Aminopropyltrimethoxysilane (AMMO), 3-aminopropyltriethoxysilane (AMEO), 2-aminoethyl-3-aminopropyltrimethoxysilane (DAMO) and trimethoxysilylpropyldiethylenetetramine (TRIAMO) are particularly preferred as adhesion promoters. Other silanes are described, for example, in EP 3000792 A1.

[0032] The adhesion promoter may be contained in an amount of up to 10 wt %, preferably 0.1 wt % to 5 wt %, more preferably 1.0 wt % to 2.5 wt %, based on the total weight of the curing agent component (B).

[0033] Inorganic fillers, specifically cements such as Portland cement or aluminate cement, and other hydraulically cured inorganic substances, quartz, glass, corundum, porcelain products, pottery, barite, light spar, gypsum, talc and / or chalk and mixtures thereof are used as fillers. Thickeners (such as fumed silica) can also be used as inorganic fillers. For example, other details of usable fillers are described in WO2020 / 058015A1. The inorganic filler can be added in the form of sand, powder or molded body, preferably in the form of fiber or ball. Fillers may also be present in one or all components of the multi-component composition.

[0034] The proportion of fillers, based on the total weight of the curing agent component (B), is preferably 0% to 75% by weight, for example 10% to 75% by weight, preferably 15% to 75% by weight, and more preferably 20% to 50% by weight, even more preferably 25% to 40% by weight.

[0035] The epoxy resin component (A) comprises at least one curable epoxy resin. As the curable epoxide in the epoxy resin component (A), various compounds known to those skilled in the art and commercially available for this purpose are considered to contain more than one epoxy group, preferably two epoxy groups per molecule on average. These epoxy resins can be saturated and unsaturated and aliphatic, alicyclic, aromatic or heterocyclic, and also have hydroxyl groups. In addition, they can contain substituents that do not cause any interfering side reactions under mixing or reaction conditions, such as alkyl or aryl substituents, ether groups, etc. Tripolymers and tetrapolymer epoxides are also suitable within the scope of the present invention.

[0036] The epoxy resin is preferably a glycidyl ether derived from a polyol, especially a glycidyl ether derived from a polyhydric phenol such as bisphenol and novolac, especially those having an average glycidyl functionality of 1.5 or more, especially 2 or more, for example 2 to 10.

[0037] The epoxy resin may have an epoxy equivalent weight (EEW) of 120 g / EQ to 2,000 g / EQ, preferably 140 to 400, specifically 155 to 195, for example 165 to 185. A mixture of multiple epoxy resins may also be used.

[0038] Examples of polyhydric phenols for preparing epoxy resins are resorcinol, hydroquinone, 2,2-bis-(4-hydroxyphenyl)propane (bisphenol A), dihydroxyphenylmethane (bisphenol F), tetrabromobisphenol A, novolac, 4,4'-dihydroxyphenylcyclohexane and isomer mixtures of 4,4'-dihydroxy-3,3'-dimethyldiphenylpropane. The epoxy resin is preferably a diglycidyl ether of bisphenol A or bisphenol F or a mixture thereof. Particularly preferred are liquid diglycidyl ethers based on bisphenol A and / or F having an EEW of 180 g / EQ to 190 g / EQ.

[0039] Further examples are hexanediol diglycidyl ether, trimethylolpropane triglycidyl ether, bisphenol A-epichlorohydrin resins and / or bisphenol F-epichlorohydrin resins, for example with an average molecular weight of Mn<2000 g / mol.

[0040] The proportion of epoxy resin, based on the total weight of epoxy resin component (A), is >0% to 100% by weight, preferably 10% to 70% by weight and particularly preferably 30% to 60% by weight.

[0041] In addition to the epoxy resin, the epoxy resin component (A) may optionally contain at least one reactive diluent. Glycidyl ethers of aliphatic, alicyclic or aromatic monoalcohols or, in particular, polyols having a lower viscosity than epoxides containing aromatic groups are used as reactive diluents. Examples of reactive diluents are monoglycidyl ethers, such as o-cresyl glycidyl ether, and glycidyl ethers having an epoxide functionality of at least 2, such as 1,4-butanediol diglycidyl ether (BDDGE), cyclohexanedimethanol diglycidyl ether and hexanediol diglycidyl ether, and tri- or higher glycidyl ethers, such as glycerol triglycidyl ether, pentaerythritol tetraglycidyl ether, trimethylolpropane triglycidyl ether (TMPTGE) or trimethylolethane triglycidyl ether (TMETGE), of which trimethylolethane triglycidyl ether is preferred. It is also possible to use mixtures of two or more of these reactive diluents, preferably mixtures containing triglycidyl ethers, particularly preferably as mixtures of 1,4-butanediol diglycidyl ether (BDDGE) and trimethylolpropane triglycidyl ether (TMPTGE) or 1,4-butanediol diglycidyl ether (BDDGE) and trimethylolethane triglycidyl ether (TMETGE).

[0042] The reactive diluent is preferably present in an amount of 0 to 60 wt.%, specifically 1 to 20 wt.%, based on the total weight of the epoxy resin component (A).

[0043] Suitable epoxy resins and reactive diluents can also be found in the standard reference "Epoxy Resins (Epoxidharze)" from Michael Dornbusch, Ulrich Christ and Rob Rasing, Vincentz Network GmbH & Co. KG (2015), ISBN 13: 9783866308770. These compounds are included here by reference.

[0044] Furthermore, the epoxy resin component (A) may contain customary additives, in particular adhesion promoters and fillers, as already described for the curing agent component (B).

[0045] Based on the total weight of the epoxy resin component (A), the proportion of the filler is preferably 0 to 75 wt.%, for example 10 to 75 wt.%, preferably 15 to 75 wt.%, and more preferably 20 to 50 wt.%, even more preferably 25 to 40 wt.%.

[0046] Further conceivable additives for the multi-component epoxy resin composition are also thixotropic agents such as optionally organically post-treated fumed silica, bentonites, alkyl- and methylcelluloses and castor oil derivatives, plasticizers such as phthalates or sebacates, stabilizers, antistatic agents, thickeners, toughening agents, curing catalysts, rheological agents, wetting agents, coloring additives such as dyes or pigments (for example for different coloring of the components to improve control of their mixing), as well as wetting agents, desensitizers, dispersants and other reaction rate controllers, or mixtures of two or more thereof. The multi-component epoxy resin composition is preferably present in a cartridge or film bag, which comprises two or more separate chambers, in which the epoxy resin component (A) and the curing agent component (B) of the mortar composition are arranged separately in order to inhibit the reaction.

[0047] For the intended use, the epoxy resin component (A) and the curing agent component (B) are discharged from separate chambers and mixed in a suitable device (e.g., a static mixer or a dissolver). The mixture of the epoxy resin component (A) and the curing agent component (B) is then introduced into a previously cleaned borehole by means of a known injection device. Subsequently, the components to be fixed are arranged in the mortar composition and adjusted. The reactive components of the curing agent component (B) react with the epoxy resin of the epoxy resin component (A) by addition polymerization, so that the epoxy resin composition cures under ambient conditions within a desired period of time, preferably within minutes or hours.

[0048] The epoxy resin component (A) and the curing agent component (B) are preferably mixed in a ratio that produces a balanced stoichiometry based on the EEW and AHEW values.

[0049] The AHEW value (amine hydrogen equivalent weight, H equivalent) indicates the amount of the curing agent component which contains 1 mol of reactive H. The EEW (epoxy equivalent weight) value is usually specified by the manufacturer of the epoxy resin component used in each case or calculated using known methods. The EEW value indicates the amount of epoxy resin in g which contains 1 mol of epoxy groups.

[0050] Experimentally, the AHEW is obtained by determining the glass transition temperature (Tg) of a mixture of an epoxy resin (with a known EEW) and an amine component. In this case, the glass transition temperature of the epoxy resin / amine mixture is determined at different ratios. The sample is cooled from 21°C to -70°C at a heating rate of -20K / min, heated to 250°C in the first heating cycle (heating rate 10K / min), then cooled again to -70°C (heating rate -20K / min), and heated to 200°C in the last step (20K / min). The sample with the highest glass transition temperature ("Tg") in the second heating cycle is then heated to 250°C (heating rate 10K / min). gThe AHEW value can be calculated from the known EEW and the optimal epoxy / amine ratio. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 1 shows the creep behavior of Example 1 and Example 2 compared with the creep behavior of Comparative Example 1;

[0052] Figure 2 The creep behavior of Examples 3 and 4 compared with the creep behavior of Comparative Example 2 is shown.

[0053] The invention is explained in more detail below with reference to a number of examples. All examples and drawings support the scope of the claims. However, the invention is not limited to the specific embodiments shown in the examples and drawings. DETAILED DESCRIPTION

[0054] Unless otherwise stated, all ingredients of the compositions listed herein are commercially available and used in customary commercial qualities.

[0055] Unless stated otherwise, all % data given in the examples relate, as calculation basis, to the total weight of the composition in question.

[0056] Table 1: List of ingredients used in the examples and references (abbreviated description) and their trade names and Supply Source

[0057]

[0058]

[0059] To prepare the epoxy resin component (A) according to Table 2, the liquid components were premixed manually using a wooden spatula. Fillers and thickeners were then added and initially premixed manually. The mixture was then stirred at 3500 rpm for 8.5 minutes at a negative pressure of 80 mbar in a dissolver (PC laboratory system, volume 1 L).

[0060] To prepare the curing agent component (B) according to Table 2, the amines were premixed and the accelerator or accelerator mixture was dissolved in the amine mixture. The filler and thickener were then added and premixed manually. The mixture was then stirred at 3500 rpm for 8.5 minutes at a negative pressure of 80 mbar in a dissolver (PC laboratory system, volume 1 L).

[0061] The accelerator Ca(NO3)2 is used as a solution in glycerol (1,2,3-propanetriol). To prepare the calcium nitrate solution, 400.0 g of calcium nitrate tetrahydrate are added to 100.0 g of glycerol and stirred at 50°C until completely dissolved (3 hours). In this way, a solution containing 80.0% calcium nitrate tetrahydrate is prepared.

[0062] To prepare the mortar composition, the epoxy resin component (A) and the curing agent component (B) according to the examples in Table 2 were filled into a hard barrel in a mixing ratio of 3:1. The hard barrel was equipped with a static mixer (Quadro mixer) and discharged by means of a dispenser. The first five strokes of the discharged mortar composition were discarded to ensure the correct mixing quality before they were injected into the drilled hole.

[0063] To determine the creep behavior, a continuous load test was carried out at maximum temperature capacity based on the description in the guideline ETAG 001 Part 5 (Guideline for European Technical Approval of Metal Plugs for Use in Concrete), instead of EAD 330499-00-0601. For this purpose, the mortar composition obtained by mixing the epoxy resin component (A) and the curing agent component (B) according to (Table 2) was installed in a clean (2x compressed air at 6 bar, 2x brushed air at 6 bar and 2x compressed air) 14 mm drilled hole in a steel-coated concrete cylinder (C20 / 25) with an insertion depth of 72 mm. After a curing period of 24 hours, the test was started and continued for a minimum of 40 days. The test was carried out at a temperature of 43°C.

[0064] In the case of the continuous load tests from Example 1 and Example 2 and Comparative Example 1, a continuous load of 27.1 kN was applied, while in the continuous load tests from Example 3 and Comparative Example 2 a continuous load of 28.0 kN was used, and in Example 4 a continuous load of 29.8 kN was applied. At the start of the test, the measurements were recorded at a high frequency (10 measurements / minute in the first hour), followed by 1 measurement per hour. The results are shown in Figure 1 to Figure 2 Shown in.

[0065] Table 2: Compositions of epoxy resin component (A) and curing agent component (B) and the compositions thereof according to Examples 1 to 4 The mortar compositions produced (according to the use of the present invention) and the mortar compositions according to Comparative Example 1 and Comparative Example 2 Mortar composition (not root According to the present invention) [ By weight % count]

[0066]

[0067] According to Table 2, the difference between Example 1 and Example 2 and Comparative Example 1 is only that The fact that K54 is present in different weight percentages. Figure 1 The results of a continuous load test for determining the creep behavior of the cured mortar compositions according to Example 1 and Example 2 compared to Comparative Example 1 are shown. Figure 1 Shows the content The mortar composition of K54 has improved creep behavior with lower initial displacement after sustained loading and exposure to elevated temperatures.

[0068] FIG3 shows the results of a continuous load test for determining the creep behavior of the cured mortar compositions according to Example 3 and Example 4 compared with Comparative Example 2. The curing agent component (B) according to Comparative Example 2 contains only 3 wt. % of K54 (not according to the invention). Figure 2 Shows the percentage of increased weight The mortar composition of K54 has an improved creep behavior with lower initial displacement under continuous load and elevated temperature. Compared with Example 3 and Comparative Example 2, the cured mortar composition according to Example 4 shows the best creep behavior with the lowest initial displacement despite an increased continuous load of 29.8 kN.

Claims

1. Use of at least one tertiary amine in an epoxy resin composition in a weight percentage of ≥1.0 weight %, based on the total weight of the epoxy resin composition, for improving the creep behavior of a chemical anchor produced from the epoxy resin composition.

2. The use according to claim 1, characterized in that The epoxy resin composition is a multi-component composition comprising at least one epoxy resin component (A) containing at least one curable epoxy resin, and at least one curing agent component (B) containing at least one amine reactive with epoxy groups, wherein the epoxy resin component (A) and the curing agent component (B) are present separately from each other in such a manner as to inhibit the reaction.

3. The use according to claim 2, characterized in that: The curing agent component (B) comprises ≥ 5.0 wt. % of a tertiary amine, based on the total weight of the curing agent component (B).

4. The use according to claim 3, characterized in that The weight percentage of the tertiary amine is 5.0 wt % to 20.0 wt % based on the total weight of the curing agent component (B).

5. Use according to any one of the preceding claims, characterized in that The tertiary amine contains at least three tertiary amino groups, and / or the tertiary amine has a 6-membered ring.

6. Use according to any one of the preceding claims, characterized in that The tertiary amine is selected from the group consisting of 2,4,6-tris(di-C1-C6-alkylaminophenol) and 1,3,5-tris[3-(dimethylamino)propyl]hexahydro-1,3,5-triazine.

7. The use according to claim 6, characterized in that The tertiary amine is 2,4,6-tris(dimethylaminomethyl)phenol.

8. The use according to any one of claims 2 to 7, characterized in that The curing agent component (B) comprises at least one inorganic salt, preferably Ca(NO3)2 and / or Ca(CF3SO3)2.

9. The use according to any one of claims 2 to 8, characterized in that The multicomponent composition is present in a cartridge or a film bag which comprises two or more separate chambers, in which the epoxy resin component (A) and the curing agent component (B) are arranged separated from one another in such a way as to inhibit a reaction.

10. Use according to any one of the preceding claims, characterized in that The curable epoxy resin includes diglycidyl ether of bisphenol A or bisphenol F or a mixture thereof.

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