Tertiary amines for improving the 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 produced from the epoxy resin composition.

Description

Technical Field

[0001] 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 produced from the epoxy resin composition.

[0002] For some time now, curable epoxy resins and amine-based multicomponent compositions have been known and are used, for example, as chemical anchors for fastening construction elements such as anchor rods, reinforcing bars, and screws in drilled holes in various substrates such as concrete.

[0003] Chemical anchors tend to creep, especially under continuous load and at high temperatures, during the service life of the chemical anchor. In this case, creep refers to the plastic deformation or movement of the chemical anchor as a result of the influence of a sustained load. Creep significantly impairs the performance of chemical anchors, as described, for example, in R. Nilforoush; M. Nils; G. Soderlind; L. Elfgren; “Long-Term Performance of Adhesive Bonded Anchors”, Structural Journal, 2016, 113(2), 251-261. The characterization of creep and the relevant specifications of creep behavior play an important role in the durability and reliability of anchor points when using chemical anchors in the construction industry. Therefore, the specifications regarding creep behavior are used when designing anchor points in the construction industry.

[0004] EP 1716195 (B1) describes the use of tertiary amines in chemical anchor systems. A relationship is assumed between the use of tertiary amines in the hardener component of a multi-component composition and an increase in the maximum achievable glass transition temperature of the 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 a thin layer, for example in the annular gap between about 1 mm of concrete and the anchor and thus cannot be heated exothermically. Investigations in this regard have been carried out, among others, by Michel et al., Constr. Build. Mat., 2020, 231, 117206 and Kroutilova et al., J. Appl. Pol. Sci., 2006, 99, 3669. In general, in creep tests carried out below the maximum glass transition temperature of this system, since there is no maximum glass transition temperature for this system, the influence on the creep behavior of chemical anchors cannot be derived from the specification of the final glass transition temperature. Therefore, the relationship between the use of tertiary amines and the improved creep behavior of chemical anchors is not known.

[0005] In view of the above embodiments, it is desirable to be able to provide a chemical anchor having improved creep behavior, specifically an epoxy-amine based chemical anchor.

[0006] Accordingly, an object of the present invention is to provide a simple and cost-effective solution that can improve the creep behavior of chemical anchors, specifically epoxy-amine based chemical anchors. The object of the present invention is specifically to improve the creep behavior of epoxy-amine based chemical anchors at high temperatures, preferably from 40 °C to 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 the epoxy resin composition in a weight percentage of 1.0% by weight or more 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 may optionally be combined with each other.

[0008] Within the context of the present invention, the terms used in the description above and below have the following meanings.

[0009] "Creep behavior" refers to the plastic deformation, displacement, or movement of a chemical anchor as a result of the influence of a sustained load (continuous load).

[0010] "Amine" is a compound derived from ammonia by replacing one, two, or three hydrogen atoms with hydrocarbon groups and having the general structures RNH2 (primary amine), R2NH (secondary amine), and R3N (tertiary amine) (see IUPAC Compendium of Chemical Terminology, 2nd ed. ("Gold Book"), edited by A.D. McNaught, and A. Wilkinson, Blackwell Scientific Publications, Oxford (1997)).

[0011] Surprisingly, it has just been found that by using at least one tertiary amine in a weight percentage of 1.0% by weight or more based on the total weight of the epoxy resin composition, the creep behavior of chemical anchors produced from the epoxy resin composition is significantly improved.

[0012] The epoxy resin composition is preferably a multi-component epoxy resin composition, preferably a two-component epoxy resin composition containing an epoxy resin component (A) and a curing agent component (B). The epoxy resin component (A) contains at least one curable epoxy resin. The curing agent component (B) contains at least one amine that is reactive with an epoxy group. 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 suppresses the reaction.

[0013] For improving the creep behavior of the chemical anchor, it is important for the present invention that at least one tertiary amine of 1.0% by weight or more based on the total weight of the epoxy resin composition is used in the epoxy resin composition.

[0014] The tertiary amine is preferably used in the curing agent component (B) of the multi-component epoxy resin composition. The curing agent component (B) preferably contains 5.0% by weight or more, preferably 5.0 - 20% by weight of the tertiary amine based on the total weight of the curing agent component (B). In a preferred embodiment of the present invention, the curing agent component (B) contains 5.0 - 10.0% by weight of the tertiary amine based on the total weight of the curing agent component (B).

[0015] The epoxy resin composition is used for manufacturing chemical anchors commonly used for construction purposes. The expression "construction purposes" means structurally adhering concrete / concrete, steel / concrete, or steel / steel, or one of these materials to another mineral material, structurally strengthening components made of concrete, bricks, and other mineral materials, applying reinforcement to a building using fiber-reinforced polymers, chemically fastening the surface made of concrete, steel, or other mineral materials. Specifically, it refers to chemically fastening construction elements and anchor means such as anchor rods, anchor bolts, (threaded) rods, (threaded) sleeves, reinforcing bars, screws, etc. into drilled holes in various substrates such as (reinforced) concrete, bricks, other mineral materials, metals (e.g., steel), ceramics, plastics, glass, and wood.

[0016] The tertiary amine used for the use according to the present invention preferably contains at least 3 tertiary amino groups. The tertiary amine used for the use according to the present invention preferably contains a 6-membered ring. In a preferred embodiment, the tertiary amine contains at least 3 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 (commercially available under the trade name Ancamine® K54) and 1,3,5-tris[3-(dimethylamino)propyl]hexahydro-1,3,5-triazine (commercially available under the trade name Lupragen® N600).

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

[0020] The curing agent component (B) contains at least one amine that is reactive with an epoxy group. The corresponding amines are known to those skilled in the art. Preferably, at least one amine that is reactive with an epoxy group is selected from the group consisting of aliphatic, cycloaliphatic, aromatic, and araliphatic amines and has an average of at least 2 reactive hydrogen atoms bonded to a nitrogen atom per molecule.

[0021] While not intending to limit the scope of the present invention in any way, examples of amines that are reactive with epoxy groups are specified below: 1,2-diaminoethane (ethylenediamine), 1,2-propanediamine, 1,3-propanediamine, 1,4-diaminobutane, 2,2-dimethyl-1,3-propanediamine (neopentanediamine), 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-bis(aminomethyl)-cyclohexane, 1,2-bis(aminomethyl)cyclohexane, hexamethylenediamine (HMD), 1,2- and 1,4-diaminocyclohexane (1,2-diaminocyclohexane, 1,2-DACH, and 1,4-diaminocyclohexane, 1,4-DACH), bis(4-amino-3-methylcyclohexyl)methane, diethylenetriamine (DETA), 4-azapentane-1,7-diamine, 1,11-diamino-3,6,9-trioxundecane, 1,8-diamino-3,6-dioxaoctane, 1,5-diamino-methyl-3-azapentane, 1,10-diamino-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-benzenedimethanamine (m-xylylenediamine (MXDA)), 1,4-benzenedimethanamine (p-xylylenediamine (PXDA)), 5-(aminomethyl)bicyclo[[2.2.1] Hept-2-yl]methylamine (norbornane diamine (NBDA)), dimethyldipropyltriamine, dimethylaminopropylaminopropylamine (DMAPAPA), 3-aminomethyl-3,5,5-trimethylcyclohexylamine (isophorone diamine (IPDA)), diaminodicyclohexylmethane (PACM), diethylmethylbenzenediamine (DETDA), 4,4'-diaminodiphenylsulfone (dapsone), mixed polycyclic amine (MPCA) (e.g., Ancamine 2168), dimethyldiaminodicyclohexylmethane (Laromin C260), 2,2-bis(4-aminocyclohexyl)propane, (3(4),8(9)bis(aminomethyl)dicyclo[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 (DYTEK® A), 3-aminomethyl-3,5,5-trimethylcyclohexane (IPDA), 1,3-benzenedimethanamine (m-xylylenediamine, MXDA), 1,4-benzenedimethanamine (p-xylylenediamine, 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)dicyclo[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 polyoxypropylene di- and triamines, 2,5-diamino-2,5-dimethylhexane, bis(aminomethyl)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 can be used individually and also in mixtures of two or more of the amines specified.

[0024] The amines reactive with epoxy groups are preferably contained in the curing agent 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 curing agent component (B).

[0025] The hardener component (B) preferably contains a salt (S) selected from the group consisting of nitrates, halogen salts, trifluoromethanesulfonates, and combinations thereof. The following compounds are particularly suitable for use as the salt (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 triflate), Mg(CF3SO3)2 (magnesium triflate), and Li(CF3SO3)2 (lithium triflate). The salts can be used individually and also in mixtures of two or more of the specified salts. The salt (S) is preferably contained in the hardener component (B) in a proportion of 0.1 to 15% by weight, preferably 1.0 to 10.0% by weight, based on the total weight of the hardener component (B).

[0026] To improve the dissolution characteristics of the salt (S) in the hardener component (B), the salt (S) can be dissolved in a suitable solvent and used as a solution accordingly. Organic solvents such as methanol, ethanol, and glycerol are suitable for this purpose.

[0027] The hardener component (B) can contain additional additives from the group of solvents, further phenolic accelerators, co-accelerators, adhesion promoters, and inorganic fillers.

[0028] The non-reactive diluent (solvent) may preferably be contained in an amount of up to 30% by weight, for example 1 to 20% by weight, based on the total weight of the curing agent component (B). Examples of suitable solvents are alcohols such as methanol, ethanol, or glycols, lower alkyl ketones such as acetone, di-lower alkyl lower alkanoylamides such as dimethylacetamide, lower alkyl benzenes such as xylene or toluene, phthalic acid esters, or paraffin. The amount of the solvent is preferably less than 5% by weight based on the total weight of the curing agent component (B).

[0029] The phenol accelerator is preferably selected from salicylic acid, styrenated phenol, 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, novolak resin, imidazole, organic phosphine, toluenesulfonic acid, Lewis base or Lewis acid, such as phosphoric acid ester, or a mixture of two or more of them can be used as a co-accelerator. The co-accelerator is preferably contained in the curing agent component (B) in a weight ratio of 0.001 to 5% by weight based on the total weight of the curing agent component (B).

[0031] By using an accelerator, crosslinking with the mortar mass on the borehole wall is improved, thereby increasing adhesion in the cured state. Suitable adhesion promoters are selected from the group of silanes having at least one Si-bonded hydrolyzable group such as 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, N-2-(aminoethyl)-3-aminopropylmethyldiethoxysilane, N-2-(aminoethyl)-3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, N-phenyl-3-aminoethyl-3-aminopropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, and 3-mercaptopropylmethyldimethoxysilane. 3-aminopropyltrimethoxysilane (aminopropyltrimethoxysilane, AMMO), 3-aminopropyltriethoxysilane (aminopropyltriethoxysilane, AMEO), 2-aminoethyl-3-aminopropyltrimethoxysilane (DAMO), and trimethoxysilylpropyldiethylenetetramine (trimethoxysilylpropyldiethylenetetramine, TRIAMO) are particularly preferred as adhesion promoters. Further silanes are described, for example, in European Patent No. 3000792 (A1).

[0032] The adhesion promoter may be contained in an amount of up to 10% by weight, preferably 0.1 to 5% by weight, more preferably 1.0 to 2.5% by weight, 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 hydraulic inorganic substances, quartz, glass, corundum, porcelain, 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. Further details of the fillers that can be used are specified, for example, in International Publication No. WO 2020 / 058015 (A1). The inorganic fillers can be added in the form of sand, powder, or shaped bodies, preferably in the form of fibers or balls. The fillers may be present in one or all of the components of the multi-component composition.

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

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

[0036] The epoxy resin is preferably a glycidyl ether derived from a polyhydric alcohol, specifically a polyhydric phenol such as bisphenol and novolak, specifically having an average glycidyl group functionality of 1.5 or more, particularly 2 or more, for example 2 to 10.

[0037] The epoxy resin can have an epoxy equivalent weight (EEW) of 120 to 2000 g / EQ, preferably 140 to 400, particularly 155 to 195, for example 165 to 185. It is also possible to use a mixture of multiple epoxy resins.

[0038] Examples of polyhydric phenols used to prepare the epoxy resin are resorcinol, hydroquinone, 2,2-bis-(4-hydroxyphenyl)propane (bisphenol A), an isomer mixture of dihydroxyphenylmethane (bisphenol F), tetrabromobisphenol A, novolak, 4,4'-dihydroxyphenylcyclohexane, and 4,4'-dihydroxy-3,3'-dimethyldiphenylpropane. The epoxide resin is preferably diglycidyl ether of bisphenol A or diglycidyl ether of bisphenol F, or a mixture thereof. Liquid diglycidyl ethers of bisphenol A and / or bisphenol F having an EEW of 180 to 190 g / EQ are particularly preferred.

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

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

[0041] In addition to the epoxy resin, the epoxy resin component (A) may optionally contain at least one reactive diluent. Aliphatic, cycloaliphatic, or aromatic monoalcohols, or in particular glycidyl ethers of polyhydric alcohols, which have a lower viscosity than epoxies 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 at least two epoxide functionalities such as 1,4-butanediol diglycidyl ether (BDDGE), cyclohexanedimethanol diglycidyl ether, and hexanediol diglycidyl ether, as well as tri- or higher-order glycidyl ethers such as glycerol triglycidyl ether, pentaerythritol tetraglycidyl ether, trimethylolpropane triglycidyl ether (TMPTGE), or trimethylolethane triglycidyl ether (TMETGE), with trimethylolethane triglycidyl ether being preferred. Mixtures of two or more of these reactive diluents, preferably mixtures containing triglycidyl ether, particularly preferably a mixture of 1,4-butanediol diglycidyl ether (BDDGE) and trimethylolpropane triglycidyl ether (TMPTGE) or a mixture of 1,4-butanediol diglycidyl ether (BDDGE) and trimethylolethane triglycidyl ether (TMETGE) can also be used.

[0042] The reactive diluent is preferably present in an amount of 0 to 60% by weight, particularly 1 to 20% by weight, 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 Michael Dornbusch, Ulrich Christ and Rob Rasing, “Epoxidharze,” Vincentz Network GmbH & Co. KG (2015), ISBN 13: 9783866308770. These compounds are hereby incorporated by reference into this specification.

[0044] Furthermore, the epoxy resin component (A) can contain conventional additives, specifically adhesion promoters and fillers, as already described for the curing agent component (B).

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

[0046] Further contemplated additives to the multi-component epoxide resin composition are also optionally organically post-treated fumed silica, bentonite, alkyl- and methylcellulose, and thixotropic agents such as castor oil derivatives, plasticizers such as phthalic esters or sebacic esters, stabilizers, antistatic agents, thickeners, softeners, curing catalysts, rheology aids, wetting agents, coloring additives such as dyes or pigments (e.g., for different colorings of the components for improved control of their mixing), and wetting agents, desensitizers, dispersants, and other controllers for the reaction rate, or mixtures of two or more of them. The multi-component epoxide resin composition is preferably present in a cartridge or film pouch having two or more separate chambers in which the epoxide resin component (A) and the curing agent component (B) of the mortar composition are separately arranged so as to suppress the reaction.

[0047] For use as intended, the epoxy resin component (A) and the curing agent component (B) are discharged from separate chambers and mixed in a suitable device, such as a static mixer or dissolver. Thereafter, the mixture of the epoxy resin component (A) and the curing agent component (B) is introduced into a pre-cleaned borehole by means of a known injection device. Subsequently, the components to be fixed are placed and adjusted in the mortar composition. The reactive constituents of the curing agent component (B) react with the epoxy resin of the epoxy resin component (A) by polyaddition, whereby the epoxy resin composition cures under ambient conditions within a desired period, preferably within a few minutes or hours.

[0048] The epoxy resin component (A) and the curing agent component (B) are preferably mixed in a ratio such that a balanced stoichiometry is obtained according to the EEW value and the AHEW value.

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

[0050] The AHEW was obtained experimentally by measuring the glass transition temperature (Tg) of a mixture of an epoxy resin (having a known EEW) and an amine component. In this case, the glass transition temperature of the epoxy resin / amine mixture was measured at different ratios. The sample was cooled from 21 °C to -70 °C at a heating rate of -20 K / min, heated to 250 °C in the first heating cycle (heating rate 10 K / min), then cooled back to -70 °C (heating rate -20 K / min), and finally heated to 200 °C in the last step (20 K / min). The mixture having the highest glass transition temperature ( "T g 2") in the second heating cycle has the optimal ratio of epoxy resin to amine. The AHEW value can be calculated from the known EEW and the optimal epoxide resin / amine ratio.

Brief Description of the Drawings

[0051]

Figure 1

Figure 2

[0052] The present invention will be described in more detail below with reference to several examples. All examples and drawings support the claims. However, the present invention is not limited to the specific embodiments shown in the examples and drawings.

[0053] Embodiment Unless otherwise specified, all the components of the compositions listed here are commercially available and used with normal commercial quality.

[0054] Unless otherwise specified, all % data shown in the examples are related to the total weight of the compositions described as the calculation basis.

Table 1

[0055] To prepare the epoxy resin component (A) according to Table 2, the liquid components were premixed manually using a wooden spatula. Then, the filler and thickener were added and premixed manually first. Then, the mixture was stirred in a dissolver (PC laboratory system, capacity 1 L) at 3500 rpm for 8.5 minutes under a negative pressure of 80 mbar.

[0056] To prepare the curing agent component (B) according to Table 2, the amine was premixed, and the accelerator or accelerator mixture was dissolved in the amine mixture. Then, the filler and thickener were added and premixed manually. Then, the mixture was stirred in a dissolver (PC laboratory system, capacity 1 L) at 3500 rpm for 8.5 minutes under a negative pressure of 80 mbar.

[0057] The accelerator Ca(NO3)2 was used as a glycerol (1,2,3-propanetriol) solution. To prepare the calcium nitrate solution, 400.0 g of calcium nitrate tetrahydrate was added to 100.0 g of glycerol and stirred at 50 °C for 3 hours until completely dissolved. The solution prepared in this way contained 80.0% calcium nitrate tetrahydrate.

[0058] 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 rigid cartridge at a mixing ratio of 3:1. A static mixer (Quadro mixer) was installed in the rigid cartridge and discharged by a dispenser. After discarding the first 5 strokes of the discharged mortar composition to ensure accurate mixing quality, they were injected into the excavation hole.

[0059] To measure the creep behavior, a continuous load test was carried out at the maximum temperature capacity based on the description in Guideline ETAG 001 Part 5 (Guideline for European Technical Approval of Metal Plugs for Use in Concrete) (replaced by 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 placed in a clean (air compressed twice at 6 bar, brushed twice, and air compressed twice at 6 bar) 14 mm excavation hole in a steel-clad concrete cylinder (C20 / 25) at an insertion depth of 72 mm. After curing for 24 hours, the test was started and carried out for at least 40 days. The test was carried out at a temperature of 43 °C.

[0060] In the case of the continuous load tests of Example 1, Example 2 and Comparative Example 1, a continuous load of 27.1 kN was applied, in the continuous load tests of Example 3 and Comparative Example 2, a continuous load of 28.0 kN was applied, and in Example 4, a continuous load of 29.8 kN was applied. At the start of these tests, the measured values were recorded at high frequency (10 measurements per minute in the first hour), and then recorded at one measurement per hour. The results are shown in Figures 1 to 2.

Table 2

[0061] Examples 1 and 2 according to Table 2 differ from Comparative Example 1 only in the fact that Ancamine® K54 is present in different weight percentages. FIG. 1 shows the results of a continuous load test for measuring the creep behavior of the hardened mortar compositions according to Examples 1 and 2 compared to Comparative Example 1. FIG. 1 shows an improved creep behavior with a lower initial displacement after sustained loading and exposure to high temperature for the mortar compositions containing Ancamine® K54.

[0062] FIG. 3 shows the results of a continuous load test for measuring the creep behavior of the hardened mortar compositions according to Examples 3 and 4 compared to Comparative Example 2. The hardening agent component (B) according to Comparative Example 2 contains Ancamine® K54 at a weight percentage of only 3% by weight (not according to the present invention). FIG. 2 shows an improved creep behavior with a lower initial displacement under sustained load and at high temperature for the mortar compositions containing an increased weight percentage of Ancamine® K54. The hardened 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 compared to Examples 3 and Comparative Example 2.

Claims

1. Use of at least one tertiary amine in the epoxy resin composition in a weight percentage of 1.0% by weight or more 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 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 an epoxide group, wherein the epoxy resin component (A) and the curing agent component (B) are present separately from each other in a manner that suppresses reaction. The use according to claim 1, characterized in that.

3. The use according to claim 2, characterized in that the curing agent component (B) contains a tertiary amine in an amount of 5.0% by weight or more 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 to 20.0% by weight based on the total weight of the curing agent component (B).

5. The use according to any one of claims 1 to 4, characterized in that the tertiary amine contains at least three tertiary amino groups and / or the tertiary amine has a six-membered ring.

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

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

8. The hardener component (B) contains at least one inorganic salt, preferably Ca(NO ３ ), ２ and / or Ca(CF ３ SO ３ ), ２ Use according to any one of claims 2 to 7, characterized in that it comprises the same.

9. The use according to any one of claims 2 to 8, characterized in that the multi-component composition is present in a cartridge or film pouch having two or more separate chambers in which the epoxy resin component (A) and the curing agent component (B) are arranged separately from each other in a manner that suppresses reaction.

10. The use according to any one of claims 1 to 9, characterized in that the curable epoxy resin contains diglycidyl ether of bisphenol A or diglycidyl ether of bisphenol F, or a mixture thereof.

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