Chemical anchor based on isocyanate-amine with improved storage stability and its use

DE502022002653D1Active Publication Date: 2025-01-30HILTI AG
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Patent Information

Application Number
DE502022002653
Authority / Receiving Office
DE · DE
Patent Type
Patents
Current Assignee / Owner
Priority Date
2021-03-16
Filing Date
2022-03-04
Publication Date
2025-01-30
Estimated Expiration
2042-03-04

AI Technical Summary

Technical Problem

Existing binder systems for chemical fastening of construction elements, particularly those based on isocyanate-amine adducts, suffer from inadequate storage stability and temperature robustness, with polyaspartic acid esters leading to softening at elevated temperatures and instability in storage.

Method used

A multi-component resin system comprising an isocyanate component with aliphatic and/or aromatic polyisocyanates and an amine component with an average NH functionality of 2 or greater, free from polyaspartic acid esters, incorporating a molecular sieve as a drying agent to enhance storage stability, and filled with inorganic fillers and rheology additives to achieve a total filling level of 30-80% in the mortar mass.

Benefits of technology

The system demonstrates improved storage stability and temperature robustness, preventing blistering and mortar leakage during storage, even at elevated temperatures, while maintaining effective bonding properties.

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Description

[0001] The present invention relates to a multi-component resin system for producing a mortar composition based on isocyanate-amine adducts for the chemical fastening of structural elements. The invention further comprises a mortar composition based on isocyanate-amine adducts produced from the multi-component resin system. The present invention also relates to a method and the use of a mortar composition based on the isocyanate-amine adducts for the chemical fastening of structural elements in mineral substrates.

[0002] Binder systems based on radically curing compounds such as methacrylate resins or epoxy resins reacted with amine hardeners are typically used to produce mortars for the chemical fastening of structural elements, such as anchor rods, reinforcing bars, and screws in drilled holes. Countless commercially available products based on these binder systems exist.

[0003] However, the known binder systems show insufficient properties, especially under critical external conditions, such as elevated temperatures, uncleaned boreholes, moist or water-filled boreholes, diamond-drilled boreholes, boreholes in cracked concrete, etc.

[0004] In addition to the further development and improvement of existing binder systems, efforts are also being made to investigate binder systems other than those mentioned above with regard to their suitability as a basis for mortar compounds for chemical fixing. For example, EP 3 447 078 A1 describes a chemical anchor made from a multi-component compound comprising a polyisocyanate component and a polyaspartic acid ester component. When the two components are mixed, a polyaddition reaction produces polyurea, which forms the binder of the mortar compound.

[0005] A disadvantage of this mortar is that the polyaspartic acid esters used lead to insufficient crosslinking and soften significantly at temperatures of 80 °C, thus exhibiting poor performance at high temperatures. Furthermore, the cured specimens are not stable to bases.

[0006] To overcome these disadvantages, a multi-component resin system was developed which, based on EP 3 447 078 A1, uses an amine with an average NH functionality of at least 2 instead of the polyaspartic acid ester, as described in the unpublished European patent application No. 20 164 633.8.

[0007] However, this system has the disadvantage that the compositions are not very stable in storage.

[0008] There is therefore a need for mortar compositions based on isocyanate-amine adducts which have improved storage stability compared to the systems mentioned in application No. 20 164 633.8.

[0009] The object of the present invention is therefore to provide a multi-component resin system and a mortar composition, each based on isocyanate-amine adducts, which has improved storage stability.

[0010] The object underlying the invention is achieved by providing a multi-component resin system according to claim 1. Preferred embodiments of the multi-component resin system according to the invention are specified in the subclaims, which can optionally be combined with one another.

[0011] The invention further relates to a mortar composition for chemically fixing structural elements according to claim 14, produced from the multi-component resin system according to the invention.

[0012] The invention also relates to the use of a molecular sieve to improve the storage stability of the isocyanate component and thus of multi-component resin systems for chemical fastening according to claim 16.

[0013] The invention also relates to a method for chemically fixing construction elements in mineral substrates according to claim 17.

[0014] A first subject matter of the invention is a multi-component resin system containing an isocyanate component which comprises at least one aliphatic and / or aromatic polyisocyanate having an average NCO functionality of 2 or greater, and an amine component which comprises at least one amine reactive towards isocyanate groups and having an average NH functionality of 2 or greater, with the proviso that the multi-component resin system is free of polyaspartic acid esters, wherein the isocyanate component and / or the amine component comprises at least one filler and at least one rheology additive, and the total filler content of a mortar composition produced by mixing the isocyanate component and the amine component is in a range from 30 to 80%, which is characterized in that the isocyanate component contains a molecular sieve as a drying agent.

[0015] It has been shown that the presence of polyaspartic acid esters in isocyanate-amine-based binder systems used in mortars for chemical bonding has a negative impact on the thermal robustness of the cured mortars. In particular, such systems exhibit significantly reduced bond strength at elevated temperatures, such as 80 °C.

[0016] It is also essential that the multi-component resin system, and in particular the amine component of the multi-component resin system, is free of polyaspartic acid esters. "free of polyaspartic acid esters"For the purposes of the present application, this means that the proportion of polyaspartic acid esters in the multicomponent resin system is preferably less than 2 wt. %, more preferably less than 0.5 wt. %, and even more preferably less than 0.1 wt. %, in each case based on the total weight of the multicomponent resin system. The presence of polyaspartic acid esters in the aforementioned weight percentage ranges can be attributed to potential impurities. However, the proportion of polyaspartic acid esters in the multicomponent resin system is particularly preferably 0.0 wt. %, based on the total weight of the multicomponent resin system.

[0017] For a better understanding of the invention, the following explanations of the terminology used herein are considered useful. For the purposes of the invention: "Multi-component resin system"a reactive resin system comprising several components stored separately from one another, generally a resin component and a hardener component, so that curing only occurs after all components have been mixed. "Isocyanates" are compounds that have a functional isocyanate group -N=C=O and are characterized by the structural unit RN=C=O. "Polyisocyanates" are compounds that have at least two functional isocyanate groups -N=C=O; diisocyanates, which also fall under the definition of polyisocyanate, are characterized, for example, by the structure O=C=NRN=C=O and thus have an NCO functionality of 2. "medium NCO functionality", describes the number of isocyanate groups in the compound; for a mixture of isocyanates, the "averaged NCO functionality"the average number of isocyanate groups in the mixture and is determined according to the formula: average NCO functionality (mixture) = Σ average NCO functionality (isocyanate i) / ni , i.e. the sum of the average NCO functionality of the individual component divided by the number of individual components. "Isocyanate component" or A component a component of the multi-component resin system which comprises at least one polyisocyanate and optionally at least one filler and / or at least one rheology additive and / or further additives. "Amine"are compounds with a functional NH group derived from ammonia by replacing one or two hydrogen atoms with hydrocarbon groups and having the general structures RNH 2 (primary amines) and R 2 NH (secondary amines) (see: IUPAC Compendium of Chemical Terminology, 2nd ed. (the "Gold Book"), Compiled by A.D. McNaught and A. Wilkinson, Blackwell Scientific Publications, Oxford (1997)). The term "amines" explicitly excludes the compound class of polyaspartic acid esters within the meaning of the present invention. These are defined separately under the term "polyaspartic acid esters." "NH functionality" describes the number of active hydrogen atoms that can react with an isocyanate group in an amino group. "medium NH functionality"describes the number of active hydrogen atoms that can react with an isocyanate group in an amine and results from the number and NH functionality of the amino groups contained in the compound, the amine; in a mixture of amines, the "averaged NH functionality" The average number of active hydrogen atoms in the mixture is determined according to the formula: average NH functionality (mixture) = Σ average NH functionality (amine i) / ni , i.e., the sum of the average NH functionality of the individual components divided by the number of individual components. "Polyaspartic acid esters" refers to compounds of the general formula: in which R 1< and R 2< may be the same or different and represent an organic radical which is inert towards isocyanate groups, X represents an n-valent organic radical which is inert towards isocyanate groups, and n represents an integer of at least 2, preferably from 2 to 6, more preferably from 2 to 4 and particularly preferably 2. "amine component" or B component, a component of the multi-component resin system, which comprises at least one amine and optionally at least one filler and / or at least one rheology additive and / or other additives. "Isocyanate-amine adducts" are polymers formed by the polyaddition reaction of isocyanates with amines. The isocyanate-amine adducts according to the invention are preferably polyureas which have at least one structural element of the form -[-NH-R-NH--NH-R'-NH-]. "aliphatic compounds" are acyclic or cyclic, saturated or unsaturated carbon compounds, excluding aromatic compounds. "alicyclic compounds" are compounds with a carbocyclic ring structure, excluding benzene derivatives or other aromatic systems. "araliphatic compounds" are aliphatic compounds with an aromatic backbone, so that in the case of a functionalized araliphatic compound, an existing functional group is attached to the aliphatic and not the aromatic part of the compound. "aromatic compounds" are compounds that follow the Hückel (4n+2) rule. "two-component reaction resin system" means a reaction resin system which comprises two components stored separately from one another, in this case an isocyanate component and an amine component, so that curing only occurs after the two components have been mixed. "mortar mass" refers to the composition obtained by mixing the isocyanate component and the amine component and as such can be used directly for chemical fastening. "Filler"means an organic or inorganic, especially inorganic, compound. "Rheology additive" Describes additives capable of influencing the viscosity behavior of the isocyanate component, the amine component, and the multicomponent resin system during storage, application, and / or curing. The rheology additive prevents, among other things, sedimentation of the fillers in the polyisocyanate component and / or the amine component. Furthermore, it improves the miscibility of the components and prevents possible phase separation. "Temperature robustness" refers to the change in the bond stress of a cured mortar mass at an elevated temperature compared to the reference bond stress. In the context of the present invention, temperature robustness is specifically defined as the ratio of the bond stress at 80 °C to the reference stress. "a", "an", "one"as an article before a chemical class of compounds, e.g. before the word "filler", that one or more compounds falling within this chemical class of compounds, e.g. various "fillers", can be meant. "at least one", "at least one", "at least one" numerically "one or more"; In a preferred embodiment, this term is numerically "a", "an", "one" meant. "contain", "include" and "include", that in addition to the components mentioned, there may be other components; these terms are meant inclusively and therefore also include "consist of"; "consist of" is meant conclusively and means that no further components can be present; in a preferred embodiment, the terms "contain", "include" and "include" the term "consist of".

[0018] All standards mentioned in this text (e.g. DIN standards) were used in the current edition on the filing date of this application. Isocyanate compounds

[0019] The multicomponent resin system according to the invention comprises at least one isocyanate component and at least one amine component. The isocyanate component and the amine component are separated from each other prior to use to inhibit reaction.

[0020] The isocyanate component comprises at least one polyisocyanate. All aliphatic and / or aromatic isocyanates known to those skilled in the art with an average NCO functionality of 2 or greater, individually or in any desired mixtures, can be used as polyisocyanates. The average NCO functionality indicates how many NCO groups are present in the polyisocyanate. Polyisocyanate means that the compound contains two or more NCO groups.

[0021] Suitable aromatic polyisocyanates are those with aromatically bound isocyanate groups, such as diisocyanatobenzenes, toluene diisocyanates, diphenyl diisocyanates, diphenylmethane diisocyanates, diisocyanatonaphthalenes, triphenylmethane triisocyanates, but also those with isocyanate groups that are bound to an aromatic via an alkylene group, such as a methylene group, such as bis- and tris-(isocyanatoalkyl)-benzenes, -toluenes and -xylenes.

[0022] Preferred examples of aromatic polyisocyanates are: 1,3-phenylene diisocyanate, 1,4-phenylene diisocyanate, 2,4-tolylene diisocyanate, 2,5-tolylene diisocyanate, 2,6-tolylene diisocyanate, 1,3-xylylene diisocyanate, 1,4-xylylene diisocyanate, tetramethyl-1,3-xylylene diisocyanate, tetramethyl-1,4-xylylene diisocyanate, 1,3-bis(isocyanatomethyl)benzene, 1,4-bis(isocyanatomethyl)benzene, ethylphenyl diisocyanate, 2-dodecyl-1,3-phenylene diisocyanate, 2,4,6-triisopropyl-m-phenylene diisocyanate, 2,4,6-trimethyl-1,3-phenylene diisocyanate, xylylene diisocyanate, 1,5-naphthylene diisocyanate, 3,3'-dimethyl-4,4'-biphenyl diisocyanate, 3,3'-dimethoxy-4,4'-biphenyl diisocyanate, 3,3'-dimethyl-4,4'-biphenyl diisocyanate, diphenylene methane 2,4'-diisocyanate, diphenylene methane 2,2'-diisocyanate, Diphenylenemethane-4,4'-diisocyanate, triphenylmethane-4,4',4"-triisocyanate, 5-(p-isocyanatobenzyl)-2-methyl-m-phenylene diisocyanate, 4,4-diisocyanato-3,3,5,5-tetraethyldiphenylmethane, 5,5'-ureylenedi-o-tolyl diisocyanate,4-[(5-Isocyanato-2-methylphenyl)methyl]-m-phenylendiisocyanat, 4-[(3-isocyanato-4-methylphenyl)methyl]-m-phenylendiisocyanat, 2,2'-Methylen-bis[6-(o-isocyanatobenzyl)phenyl]diisocyanat.,

[0023] Preference is given to using aliphatic isocyanates which have a carbon backbone (without the NCO groups contained) of 3 to 30 carbon atoms, preferably of 4 to 20 carbon atoms. Examples of aliphatic polyisocyanates are bis(isocyanatoalkyl) ethers or alkane diisocyanates, such as methane diisocyanate, propane diisocyanates, butane diisocyanates, pentane diisocyanates, hexane diisocyanates (e.g. hexamethylene diisocyanate, HDI), heptane diisocyanates (e.g. 2,2-dimethylpentane-1,5-diisocyanate, octane diisocyanates, nonane diisocyanates (e.g. trimethyl-HDI (TMDI) usually as a mixture of the 2,4,4- and 2,2,4-isomers), 2-methylpentane-1,5-diisocyanate (MPDI), nonane triisocyanates (e.g.4-Isocyanatomethyl-1,8-octane diisocyanate, 5-methylnonane diisocyanate), decane diisocyanates, decane triisocyanates, undecane diisocyanates, undecane triisocyanates, dodecane diisocyanates, dodecane triisocyanates, 1,3- and 1,4-bis-(isocyanatomethyl)cyclohexane (H 6 XDI), 3-isocyanatomethyl-3,5,5-trimethylcyclohexyl isocyanate (isophorone diisocyanate, IPDI), bis-(4-isocyanatocyclohexyl)methane (H 12 MDI), bis-(isocyanatomethyl)norbornane (NBDI) or 3(4)-isocyanatomethyl-1-methylcyclohexyl isocyanate (IMCI), octagydro-4,7-methano-1H-indenedimethyl diisocyanate, norbornene diisocyanate, 5-Isocyanato-1-(isocyanatomethyl)-1,3,3-trimethylcyclohexane, ureylene bis(p-phenylene methylene-p-phenylene) diiscoyanate.

[0024] Particularly preferred isocyanates are hexamethylene diisocyanate (HDI), trimethyl-HDI (TMDI), pentane diisocyanate (PDI), 2-methylpentane-1,5-diisocyanate (MPDI), isophorone diisocyanate (IPDI), 1,3- and 1,4-bis(isocyanatomethyl)cyclohexane (H 6 XDI), bis(isocyanatomethyl)norbornane (NBDI), 3(4)-isocyanatomethyl-1-methylcyclohexyl isocyanate (IMCI) and / or 4,4'-bis(isocyanatocyclohexyl)methane (H 12 MDI) or mixtures of these isocyanates.

[0025] Even more preferably, the polyisocyanates are present as prepolymers, biurets, isocyanurates, iminooxadiazinediones, uretdiones and / or allophanates, which can be prepared by oligomerization of difunctional isocyanates or by reaction of the isocyanate compounds with polyols or polyamines, individually or as a mixture, and which have an average NCO functionality of 2 or greater.

[0026] Examples of suitable, commercially available isocyanates are Desmodur ®< N 3900, Desmodur ®< N 100, Desmodur ®< Ultra N 3200, Desmodur ®< Ultra N 3300, Desmodur ®< Ultra N 3600, Desmodur ®< N 3800, Desmodur ®< XP 2675, Desmodur ®< 2714, Desmodur ®< 2731, Desmodur ®< N 3400, Desmodur ®< XP 2679, Desmodur ®< XP 2731, Desmodur ®< XP 2489, Desmodur ®< E 3370, Desmodur ®< XP 2599, Desmodur ®< XP 2617, Desmodur ®< XP 2406, Desmodur ®< XP 2551, Desmodur ®< XP 2838, Desmodur ®< XP 2840, Desmodur ®< VL, Desmodur ®< VL 50, Desmodur ®< VL 51, Desmodur ®< ultra N 3300, Desmodur ®< eco N 7300, Desmodur ®< E23, Desmodur ®< E XP 2727, Desmodur ®< E 30600, Desmodur ®< E 2863 XP, Desmodur ®< H, Desmodur ®< VKS 20 F, Desmodur ®< 44V20I, Desmodur ®< 44P01, Desmodur ®< 44V70 L, Desmodur ®< N3400, Desmodur ®< N3500 (each available from Covestro AG), Tolonate ™< HDB, Tolonate ™< HDB-LV, Tolonate ™< HDT, Tolonate ™< HDT-LV, Tolonate ™< HDT-LV2 (available from Vencorex), Basonat ®< HB 100,Basonat®< HI 100, Basonat®< HI 2000 NG (available from BASF), Takenate®< 500, Takenate®< 600, Takenate®< D-132N(NS), Stabio®< D-376N (each available from Mitsui), Duranate®< 24A-100, Duranate®< TPA-100, Duranate®< TPH-100 (each available from Asahi Kasai), Coronate®< HXR, Coronate®< HXLV, Coronate®< HX, Coronate®< HK, (each available from Tosoh).

[0027] One or more polyisocyanates are preferably present in the isocyanate component in a proportion of 20 to 100 wt.%, preferably in a proportion of 30 to 90 wt.% and more preferably in a proportion of 35 to 65 wt.%, based on the total weight of the isocyanate component. Amine compounds

[0028] The amine component, which is present in the multi-component resin system separately from the isocyanate component to inhibit reaction, comprises at least one isocyanate-reactive amine which comprises one amino group, preferably at least two amino groups, as functional groups. According to the invention, the amine has an average NH functionality of 2 or greater. The average NH functionality indicates the number of hydrogen atoms bonded to a nitrogen atom in the amine. Accordingly, for example, a primary monoamine has an average NH functionality of 2, a primary diamine has an average NH functionality of 4, an amine with three secondary amino groups has an average NH functionality of 3, and a diamine with one primary and one secondary amino group has an average NH functionality of 3.The average NH functionality can also be determined according to the information provided by the amine suppliers, whereby the actually stated NH functionality may differ from the theoretical average NH functionality as understood herein. The term "average" indicates that this refers to the NH functionality of the compound and not the NH functionality of the amino group(s) contained in the compound. The amino groups can be primary or secondary amino groups. The amine can contain either only primary or only secondary amino groups, or both primary and secondary amino groups.

[0029] According to a preferred embodiment, the amine reactive towards isocyanate groups is selected from the group consisting of aliphatic, alicyclic, araliphatic and aromatic amines, particularly preferably selected from the group consisting of alicyclic and aromatic amines.

[0030] Amines reactive toward isocyanate groups are generally known to those skilled in the art. Examples of suitable amines reactive toward isocyanate groups are given below, but without limiting the scope of the invention. These can be used individually or in any desired mixtures with one another. Examples are: 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-DACH and 1,4-DACH), bis(4-amino-3-methylcyclohexyl)methane, diethylenetriamine (DETA), 4-azaheptane-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)amin, 1,13-Diamino-4,7, 10-trioxatridecan, 4-Aminomethyl-1, 8-diaminooctan, 2-Butyl-2-ethyl-1, 5-diaminopentan, N, N-Bis-(3-aminopropyl)methylamin, Triethylentetramin (TETA), Tetraethylenpentamin (TEPA), Pentaethylenhexamin (PEHA), 1,3-Benzoldimethanamin (m-Xylylendiamin, mXDA), 1,4-Benzoldimethanamin (p-Xylylendiamin, pXDA), 5-(Aminomethyl)bicyclo[[2.2.1]hept-2-yl]methylamin (NBDA, Norbornandiamin), Dimethyldipropylentriamin, Dimethylaminopropyl-aminopropylamin (DMAPAPA), 2,4-Diamino-3,5-dimethylthiotoluol (Dimethylthio-toluoldiamin, DMTDA) 3-Aminomethyl-3,5,5-trimethylcyclohexylamin (Isophorondiamin (IPDA)), Diaminodicyclohexylmethan (PACM), Diethylmethylbenzoldiamin (DETDA), 3,3'-Diaminodiphenylsulfon (33Dapson), 4,4'-Diaminodiphenylsulfon (44Dapson), gemischte polycyclische Amine (MPCA) (z.B. Ancamine 2168), Dimethyldiaminodicyclohexylmethan (Laromin C260), 2,2-Bis(4-aminocyclohexyl)propan, (3(4),8(9)Bis(aminomethyldicyclo[5.2.1.0 2,6< ]decan (Isomerengemisch,tricyclischer primärer Amine; TCD-Diamin), Methylcyclohexyl-diamin (MCDA), N,N'-Diaminopropyl-2-methyl-cyclohexan-1,3-diamin, N,N'-Diaminopropyl-4-methyl-cyclohexan-1,3-diamin, N-(3-Aminopropyl)cyclohexylamin, und 2-(2,2,6,6-tetramethylpiperidin-4-yl)propan-1,3-diamin.,

[0031] Particularly preferred amines are diethylmethylbenzenediamine (DETDA), 2,4-diamino-3,5-dimethylthiotoluene (dimethylthiotoluenediamine, DMTDA), 4,4'-methylene-bis[N-(1-methylpropyl)phenylamine], an isomer mixture of 6-methyl-2,4-bis(methylthio)phenylene-1,3-diamine and 2-methyl-4,6-bis(methylthio)phenylene-1,3-diamine (Ethacure ®< 300), 4,4'-methylenebis(2,6-diethylaniline), 4,4'-methylenebis(N-sec-butylcyclohexanamine) (Clearlink ®< 1000), 3,3'-diaminodiphenylsulfone (33Dapsone), 4,4'-diaminodiphenylsulfone (44Dapsone), N,N'-Di-sec-butyl-p-phenylenediamine and 2,4,6-trimethyl-m-phenylenediamine, 4,4'-methylenebis(N-(1-methylpropyl)-3,3'-dimethylcyclohexanamine (Clearlink ®< 3000), the reaction product of 2-propenenitrile with 3-amino-1,5,5-trimethylcyclohexanemethanamine (Jefflink ®< 745) and 3-((3-(((2-cyanoethyl)amino)methyl)-3,5,5-trimethylcyclohexyl)amino)propiononitrile (Jefflink ®< 136 or Baxxodur PC136).

[0032] Very particularly preferred amines are 4,4'-methylene-bis[N-(1-methylpropyl)phenylamine], an isomer mixture of 6-methyl-2,4-bis(methylthio)phenylene-1,3-diamine and 2-methyl-4,6-bis(methylthio)phenylene-1,3-diamine (Ethacure ®< 300), 4,4'-methylenebis(2,6-diethylaniline), 4,4'-methylenebis(N-sec-butylcyclohexanamine) (Clearlink ®< 1000), 3,3'-diaminodiphenylsulfone (33Dapsone), N,N'-di-sec-butyl-p-phenylenediamine and 2,4,6-trimethyl-m-phenylenediamine.

[0033] One or more amines are preferably present in the amine component in a proportion of 20 to 100 wt.%, preferably in a proportion of 30 to 70 wt.% and more preferably in a proportion of 35 to 70 wt.% based on the total weight of the amine component.

[0034] The proportions of the polyisocyanate and the amine of the multi-component resin system are preferably selected such that the ratio of average NCO functionality of the polyisocyanate to the average NH functionality of the amine is between 0.3 and 2.0, preferably between 0.5 and 1.8, more preferably between 0.5 and 1.5, even more preferably between 0.7 and 1.5 and most preferably 0.7 to 1.3.

[0035] To adjust the curing rate, a mixture of different polyisocyanates and / or different amines can be used. In this case, their proportions are selected such that the ratio of the average NCO functionality of the isocyanate mixture to the average NH functionality of the amine mixture is between 0.3 and 2.0, preferably between 0.5 and 1.8, more preferably between 0.5 and 1.5, further preferably between 0.7 and 1.5, and most preferably between 0.7 and 1.3. Fillers and additives

[0036] According to the invention, the isocyanate component of the multi-component resin system contains a molecular sieve, in particular a zeolite as a drying agent, which serves to increase the storage stability of the isocyanate component and thus of a multi-component resin system containing this isocyanate component.

[0037] The zeolites used in the present invention can be synthetic or natural zeolites and are generally characterized by the composition M n+< x / n [(AlO 2 ) -< x (SiO 2 ) y ]·zH 2 O where N is the charge of M, usually 1 or 2, and M is a cation of an alkali or alkaline earth metal, in particular Na +< , K +< , Ca 2+< and Mg 2+<.

[0038] The following zeolites can be used: Zeolith A (Na 12 ((AlO 2 ) 12 (SiO 2 ) 12 ) · 27 H 2 O; K 12 ((AlO 2 ) 12 (SiO 2 ) 12 ) · 27 H 2 O), Zeolith X (Na 86 [(AlO 2 ) 86 (SiO 2 ) 2 ) · 26 ], Zeolite H Y (Na 56 [(AlO 2 ) 56 (SiO 2 ) 136 ] · 250 H 2 O), Zeolith L (K 9 [(AlO 2 ) 9 (SiO 2 ) 27 ] · 22 H 2 O), Modernite (Na 8.7 [(AlO 2 ) 8.7 (SiO 2 ) 3, 23 H Zeolite ZSM 5 (Na 0.3 H 3.8 [(AlO 2 ) 4.1 (SiO 2 ) 91.9 ]), Zeolite ZSM 11 (Na 0.1 H 1 , 7 [(AlO 2 ) 1.8 (SiO Of these, Zeolith A, Zeolith X, Zeolith Y and Zeolith ZSM 5 and Zeolith ZSM 11 were prepared.

[0039] The molecular vinegar, especially the zeolite, can be applied as a powder, granule or as a paste (for example, 48-50% powder dispersed in castor oil).

[0040] The synthetic zeolite is preferably a synthetic zeolite comprising particles with a particle size of up to 250 µm, in particular 5 µm to 24 µm. The synthetic zeolite particularly preferably has a pore size of about 5 Å to about 10 Å, in particular about 3 Å to about 4 Å.

[0041] The specific surface area (BET) of the zeolite particles is preferably between 800 m 2 < / g and 1000 m 2 < / g.

[0042] The residual water content of the zeolite is below 2.5% w / w, preferably below 1.5% w / w, and the water absorption capacity is below 22 - 24% w / w.

[0043] It is possible to use a mixture of two or more different types of zeolite.

[0044] The molecular sieve, in particular the zeolite, is preferably used in an amount of 3 to 35 wt.%, preferably 3 wt.% to 20 wt.% and particularly preferably in an amount of 3 to 5 wt.%, based on the weight of the isocyanate component.

[0045] Preferably, the molecular sieve is dried before use in the isocyanate component.

[0046] By using the molecular sieve, the storage stability of the isocyanate component and thus of a multi-component resin system containing this component could be improved.

[0047] In addition to the molecular sieve, the isocyanate component and / or the amine component according to the invention contains at least one filler and at least one rheology additive. It is essential to the invention that at least one of the two components contains both a filler and a rheology additive. It is preferred that both the isocyanate component and the amine component each contain at least one filler and at least one rheology additive.

[0048] According to the invention, the total filler content of a mortar composition, including the molecular sieve, produced by mixing the isocyanate component and the amine component of the multi-component resin system is in a range from 30 to 80 wt.% based on the total weight of the mortar composition, preferably in a range from 35 to 65, even more preferably in a range from 35 to 60 wt.%. The total filler content of the mortar composition refers to the weight percentage of filler, including the molecular sieve, and rheology additive based on the total weight of the isocyanate component and the amine component. In a preferred embodiment, the filler content of the isocyanate component is up to 80 wt.%, preferably 10 to 70 wt.%, more preferably 35 to 65 wt.%, based on the total weight of the isocyanate component. The filler content of the amine component is preferably up to 80 wt.%, preferably 10 to 70 wt.%, more preferably 35 to 65 wt.-%, each based on the total weight of the amine component.

[0049] Preferred fillers are inorganic fillers, particularly cements such as Portland cement or aluminate cement, as well as other hydraulically setting inorganic materials, quartz, glass, corundum, porcelain, earthenware, barite, light spar, gypsum, talc, and / or chalk, as well as mixtures thereof. The inorganic fillers can be added in the form of sands, flours, or molded bodies, preferably in the form of fibers or spheres. By appropriately selecting the fillers in terms of type and grain size distribution / (fiber) length, application-relevant properties such as rheological behavior, extrusion forces, internal strength, tensile strength, pull-out forces, and impact strength can be controlled. Suitable fillers include, in particular, non-surface-treated quartz flours, fine quartz flours, and ultrafine quartz flours, such as Millisil®< W3, Millisil®< W6, Millisil®< W8, and Millisil®< W12, preferably Millisil®< W12.Silanized quartz flours, fine quartz flours, and ultra-fine quartz flours can also be used. These are commercially available, for example, under the Silbond ®< product series from Quarzwerke. The Silbond ®< EST (epoxysilane-modified) and Silbond ®< AST (aminosilane-treated) product series are particularly preferred. Furthermore, aluminum oxide-based fillers such as ultra-fine aluminum oxide fillers of the ASFP type from Denka, Japan, (d50 = 0.3 µm) or grades such as DAW or DAM with the type designations 45 (d50 < 0.44 µm), 07 (d50 > 8.4 µm), 05 (d50 < 5.5 µm), and 03 (d50 < 4.1 µm) can be used. Furthermore, surface-treated fine and ultrafine fillers such as Aktisil AM (aminosilane-treated, d50 = 2.2 µm) and Aktisil EM (epoxysilane-treated, d50 = 2.2 µm) from Hoffman Mineral can be used. The fillers can be used individually or in any desired combination.

[0050] The flow properties are adjusted by adding rheology additives, which are used according to the invention in the isocyanate component and / or the amine component. Suitable rheology additives include: phyllosilicates such as Laponite, bentone, or montmorillonite; Neuburg Siliceous Earth; fumed silica; polysaccharides; polyacrylate, polyurethane, or polyurea thickeners; and cellulose esters. For optimization, wetting and dispersing agents, surface additives, defoamers and deaerators, wax additives, adhesion promoters, viscosity reducers, or process additives can also be added.

[0051] The proportion of one or more rheology additives in the isocyanate component is preferably 0.1 to 3 wt.%, more preferably 0.1 to 1.5 wt.%, based on the total weight of the isocyanate component. The proportion of one or more rheology additives in the amine component is preferably 0.1 to 5 wt.%, more preferably 0.5 to 3 wt.%, based on the total weight of the amine component.

[0052] In one embodiment of the multi-component resin system, the isocyanate component and / or the amine component contains at least one silane as an adhesion promoter.

[0053] The use of a silane improves the cross-linking of the borehole wall with the mortar mass, so that the adhesion in the cured state is increased.

[0054] Suitable adhesion promoters are selected from the group of silanes, which have at least one Si-bonded hydrolyzable group. It is not necessary for the silane to have another functional group in addition to the Si-bonded hydrolyzable group, such as an isocyanate group or an amino group. Nevertheless, the silane can have one or more identical or different additional functional groups in addition to the Si-bonded hydrolyzable group, such as an amino, mercapto, epoxy, isocyanato, alkenyl, (meth)acryloyl, anhydrido, or vinyl group. The Si-bonded hydrolyzable group is preferably a C 1 -C 7 alkoxy group and very particularly preferably a methoxy or ethoxy group.

[0055] Suitable silanes are selected from the group consisting of 3-aminopropyltrialkoxysilanes, such as 3-aminopropyltrimethoxysilane and 3-aminopropyltriethoxysilane; 3-glycidyloxypropyltrialkoxysilanes, such as 3-glycidyloxypropyltrimethoxysilane and 3-glycidyloxypropyltriethoxysilane; glycidyloxymethyltrimethoxysilane; 3-glycidyloxypropylmethyldimethoxysilane; bis-(3-trialkoxysilylpropyl)amines, such as bis-(3-trimethoxysilylpropyl)amine and bis-(3-triethoxysilylpropyl)amine; 3-mercaptopropyltrialkoxysilanes, such as 3-mercaptopropyltrimethoxysilane and 3-mercaptopropylmethyldimethoxysilane; 3-(meth)acryloyloxyalkyltrialkoxysilanes, such as 3-(meth)acryloyloxypropyltrimethoxysilane, 3-(meth)acryloyloxypropyltriethoxysilane; 3-(meth)acryloyloxymethyltrimethoxysilane, 3-(meth)acryloyloxymethyltriethoxysilane and 3-(meth)acryloyloxypropylmethyldimethoxysilane; Alkenylalkoxysilanes, such as vinylalkoxysilanes, for exampleVinyltrimethoxysilane and vinyltriethoxysilane; tetraalkoxysilanes such as tetraethoxysilane, tetramethoxysilane and tetrapropoxysilane; 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, N-2-(aminoethyl)-3-aminopropylmethyldiethoxysilane, N-2-(aminoethyl)-3-aminopropyltriethoxysilane, N-phenyl-3-aminoethyl-3-aminopropyltrimethoxysilane and mixtures of two or more thereof.

[0056] Particularly suitable silanes are selected from the group consisting of 3-aminopropyltrialkoxysilanes, 3-glycidyloxyalkzltrialkoxysilanes, bis-(3-trialkoxysilylpropyl)amines, 3-mercaptopropyltrialkoxysilanes, 3-(meth)acryloyloxyalkyltrialkoxysilanes, alkenylalkoxysilanes, tetraalkoxysilanes and mixtures of two or more thereof.

[0057] Particularly suitable silanes are 3-glycidoxypropyldimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-trimethoxysilylpropyl methacrylate and vinyltrimethoxysilane.

[0058] The silane can be present in the multicomponent resin system in an amount of up to 10 wt.%, preferably 0.1 to 5 wt.%, more preferably 1.0 to 2.5 wt.%, based on the total weight of the multicomponent resin system. The silane can be present entirely in one component, i.e., the isocyanate component or the amine component, or divided between both components, i.e., divided between the isocyanate component and the amine component.

[0059] A further object is a mortar composition which is produced by mixing the isocyanate component and the amine component of the multi-component resin system.

[0060] Another object is the use of the molecular sieve, in particular the zeolite, to improve the storage stability of the isocyanate component and thus of the multi-component resin system.

[0061] The multi-component resin system is preferably present in cartridges, cartridges or foil bags, which are characterized in that they comprise two or more separate chambers in which the isocyanate component and the amine component are arranged separately from each other in a reaction-inhibiting manner.

[0062] For the intended use of the multi-component resin system, the isocyanate component and the amine component are emptied from the separate chambers and mixed in a suitable device, such as a static mixer or a dissolver. The mixture of isocyanate component and amine component (mortar mass) is then injected into the drilled hole (presumably previously cleaned) using a known injection device. The fastener to be fixed is then inserted into the mortar mass and adjusted. The reactive components of the isocyanate component react with the amino groups of the amine component under polyaddition, so that the mortar mass cures under ambient conditions within a desired time, preferably within a few minutes or hours.

[0063] The mortar composition or the multi-component resin system according to the invention is preferably used for construction purposes. The term "for construction purposes" means the construction bonding of concrete / concrete, steel / concrete, or steel / steel, or one of the aforementioned materials, to other mineral materials; the structural reinforcement of components made of concrete, masonry, and other mineral materials; the reinforcement applications of building objects with fiber-reinforced polymers; the chemical fastening to surfaces made of concrete, steel, or other mineral materials, in particular the chemical fastening of structural elements and anchoring devices, such as anchor rods, anchor bolts, (threaded) rods, (threaded) sleeves, reinforcing bars, screws, and the like, in drilled holes in various substrates, such as (reinforced) concrete, masonry, other mineral materials, metals (e.g., steel), ceramics, plastics, glass, and wood.The mortar compositions according to the invention and the multi-component resin systems according to the invention are particularly preferably used for the chemical fixing of anchoring agents.

[0064] A further object of the present invention is a method for the chemical fastening of construction elements in boreholes, wherein a multi-component resin system according to the invention or a mortar composition according to the invention as described above is used for the chemical fastening of the construction elements.The method according to the invention is particularly suitable for the construction bonding of concrete / concrete, steel / concrete or steel / steel or one of the aforementioned materials to other mineral materials, the structural reinforcement of components made of concrete, masonry and other mineral materials, the reinforcement applications with fiber-reinforced polymers of building objects, the chemical fastening to surfaces made of concrete, steel or other mineral materials, in particular the chemical fastening of structural elements and anchoring means, such as anchor rods, anchor bolts, (threaded) rods, (threaded) sleeves, reinforcing bars, screws and the like, in drill holes in various substrates, such as (reinforced) concrete, masonry, other mineral materials, metals (e.g. steel), ceramics, plastics, glass and wood. The method according to the invention is very particularly preferably used for the chemical fastening of anchoring means.

[0065] A further object of the present invention is the use of a multi-component resin system or a mortar composition according to the invention for the chemical fixing of construction elements in mineral substrates.

[0066] The invention is further described below with reference to exemplary embodiments, which, however, should not be understood in a limiting sense. Examples of implementation

[0067] The following compounds were used to prepare the comparative composition and the composition according to the invention: Hexamethylene-1,6-diisocyanate homopolymers Low-viscosity, aliphatic polyisocyanate resin based on hexamethylene diisocyanate (equivalent weight approx. 179; NCO content according to M105-ISO 11909 23.5 ± 0.5 wt.%, monomeric HDI according to M106-ISO 10283 < 0.25%; viscosity (23°C) M014-ISO 3219 / A.3 730 ± 100 mPa s; Desmodur ® < N 3900) Covestro AG Hexamethylene-1,6-diisocyanate biuret oligomerization product Desmodur ®< N 3200 Covestro AG Mixture of 6-methyl-2,4-bis(methylthio)phenylene-1,3-diamine and 2-methyl-4,6-bis(methylthio)phenylene-1,3-diamine Ethacure ®< 300 Curative (Dimethylthiotoluenediamine 95-97%, Monomethylthiotoluenediamine 2-3%; equivalent weight with isocyanates 107) Albermale Corporation 3-Glycidyloxypropyltrimethoxysilane Dynasylan ®< GLYMO Evonik Resource Efficiency GmbH Zeolite powder 1 Purmol ®< 3ST; synthetic zeolite, pore size 3Å, particle size 24 µm; Zeochem AG Zeolite powder 2 Purmol ®< 4ST; synthetic zeolite, pore size 4Å, particle size 24 µm Zeochem AG Zeolite powder 3 L-powder; synthetic zeolite, pore size 3Å, particle size 5 µm Kurt Obermeier GmbH & Co.KG Organic desiccant N-Butyl-2-(1-ethylpentyl)-1,3-oxazolidine; Incozole 2 Incorez Ltd. quartz flour Millisil ®< W12 Quartz works Frechen Quartz sand 1 Quartz sand F32 Quartz works Frechen Quartz sand 2 Quartz sand P10 Strobel Quartz Sand GmbH Silica Cab-O-Sil ®< TS-720 Cabot

[0068] The comparative compositions and the inventive compositions of the isocyanate component and the amine component are given in Table 1 below. Production of mortar mass:

[0069] In Examples 1 to 3, the zeolite powders were used undried from previously opened packages. In Examples 4 to 10, the zeolite powders were dried at 300 °C for 24 hours and then stored at 120 °C until use. The components were mixed by manual stirring and homogenized in a dissolver under vacuum to form a bubble-free, pasty mass. Storage of mortar mass

[0070] The mortar mixtures were filled into a 1K PA hard cartridge without bubbles and sealed with a stopper. The cartridges were stored vertically with the stopper facing upwards at 23°C or 40°C. After defined periods, the mortar condition was visually inspected for blistering and evaluated according to the following scheme: 1 = no blistering 2 = slight blistering 3 = significant blistering 4 = severe blistering 5 = very severe blistering

[0071] The mortar that had leaked out of the plug due to overpressure was also examined. Viscosity measurement

[0072] The viscosity of the mortar masses was determined at 25 °C using a plate / plate measuring system with a 20 mm diameter at a shear rate of 81 / s and a gap of 3 mm on a Kinexus measuring device from Malvern. Table 1: Composition of the comparative formulation, comparative formulation 4 and the inventive example formulations 1 to 3 as well as the results of the storage tests at 23°C and 40°C Examples (weight percentages) Components Comparison 1 2 3 4 (Comparison) Hexamethylene-1,6-diisocyanate homopolymer (N3900) 37.9 36.0 36.0 36.0 40.0 Hexamethylene-1,6-diisocyanate biuret oligomerization product (N3200) 6.3 6.0 6.0 6.0 - 3-Glycidyloxypropyltrimethoxysilane 3.2 3.0 3.0 3.0 - quartz flour 51.1 48.5 48.5 48.5 55.0 Silica 1.6 1.5 1.5 1.5 2.0 Zeolite powder 1, undried - 5.0 - - - Zeolite powder 2, undried - - 5.0 - - Zeolite powder 3, undried - - - 5.0 - N-Butyl-2-(1-ethylpentyl)-1,3-oxazolidine - - - - 3.0 2 weeks storage at 23 °C Visual assessment of blistering 5 2 5 1 2 Leaked mortar Yes No Yes No Yes 2 weeks storage at 40 °C Visual assessment of blistering 5 5 5 5 3 Leaked mortar Yes Yes Yes Yes Yes

[0073] In the comparative formulation, it is clearly evident that without a drying agent, CO2 is formed from the quartz powder due to the reaction of the isocyanate with the water, which leads to severe blistering after two weeks of storage at 23 °C and 40 °C. Furthermore, mortar leaked from the cartridge due to overpressure. The use of undried zeolite powder does not lead to sufficient improvement. Likewise, the use of the organic drying agent in comparative formulation 4 cannot completely prevent CO2 formation. Table 2: Composition of the inventive example formulations 5 to 11 and the results of the storage tests at 40°C Examples (weight percentages) Components 5 6 7 8 9 10 11 Hexamethylene-1,6-diisocyanate homopolymer (N3900) 40.0 40.0 40.0 40.0 40.0 40.0 40.0 quartz flour 53.0 53.0 53.0 55.0 57.0 - - Quartz sand 1 - - - - - 53.0 - Quartz sand 2 - - - - - - 53.0 Silica 2.0 2.0 2.0 2.0 2.0 2.0 2.0 Zeolite powder 1, dried - - 5.0 3.0 1.0 5.0 5.0 Zeolite powder 2, dried - 5.0 - - - - - Zeolite powder 3, dried 5.0 - - - - - - Viscosity in Pa s 189 181 198 186 179 195 201 4 weeks storage at 40 °C Visual assessment of blistering 1 1 1 1 2 1 1 Leaked mortar No No No No Yes No No Viscosity in Pa s 223 209 218 205 195 205 221 8 weeks storage at 40 °C Visual assessment of blistering 1 1 1 1 2 1 1 Leaked mortar No No No No Yes No No Viscosity in Pa s 218 195 212 198 189 205 218 12 weeks storage at 40 °C Visual assessment of blistering 1 1 1 1 2 1 1 Leaked mortar No No No No Yes No No Viscosity in Pa s 183 188 206 233 200 216 232 16 weeks storage at 40 °C Visual assessment of blistering 1 1 1 1 2 1 1 Leaked mortar No No No No Yes No No Viscosity in Pa s 190 190 210 224 226 250 264

[0074] The test results of Examples 5 and 11 clearly demonstrate that the use of dried zeolite powder in varying amounts prevents CO2 formation and achieves long storage stability even at 40 °C. This works not only with quartz flour with a relatively low water content, but also with quartz sands with a higher water content.

Claims

1. Multi-component resin system containing an isocyanate component, which comprises at least one aliphatic and / or aromatic polyisocyanate having an average NCO functionality of 2 or more, and an amine component, which comprises at least one amine which is reactive to isocyanate groups and has an average NH functionality of 2 or more, with the proviso that the multi-component resin system is free of polyaspartic acid esters, the isocyanate component and / or the amine component comprising at least one filler and at least one rheology additive and the total filling level of a mortar composition produced by mixing the isocyanate component and the amine component is in a range from 30 to 80 wt.%, characterized in that the isocyanate component contains a molecular sieve as a drying agent.

2. Multi-component resin system according to claim 1, characterized in that the molecular sieve is a zeolite.

3. Multi-component resin system according to claim 2, characterized in that the zeolite is selected from the group consisting of zeolite A (Na12((AlO2)12(SiO2)12) · 27 H2O; K12((AlO2)12(SiO2)12) · 27 H2O), zeolite X (Na86[(AlO2)86(SiO2)106] · 264 H2O), zeolite Y (Na56[(AlO2)56(SiO2)136] · 250 H2O), zeolite L (K9[(AlO2)9(SiO2)27] · 22 H2O), mordenite (Na8.7[(AlO2)8.7(SiO2)39.3] · 24 H2O), zeolite ZSM 5 (Na0.3H3.8[(AlO2)4.1(SiO2)91.9]) and zeolite ZSM 11 (Na0.1H1.7[(AlO2)1.8(SiO2)94.2]).

4. Multi-component resin system according to any of the preceding claims, characterized in that the molecular sieve is present as a powder, granular material or paste.

5. Multi-component resin system according to any of the preceding claims, characterized in that the molecular sieve is contained in an amount of 3 to 35 wt.%, based on the weight of the isocyanate component.

6. Multi-component resin system according to any of the preceding claims, characterized in that both the isocyanate component and the amine component comprise the at least one filler and the at least one rheology additive.

7. Multi-component resin system according to claim 6, characterized in that the filling level of the isocyanate component and the filling level of the amine component is from 10 to 70 wt.%, based in each case on the total weight of the isocyanate component and the amine component, respectively.

8. Multi-component resin system according to any of the preceding claims, characterized in that the polyisocyanate and the amine are present in a quantity ratio in which the ratio of the average NCO functionality of the polyisocyanate to the average NH functionality of the amine is between 0.3 and 2.0.

9. Multi-component resin system according to any of the preceding claims, characterized in that the isocyanate component comprises at least one aromatic polyisocyanate selected from the group consisting of 1,4-phenylene diisocyanate, 2,4- and / or 2,6-toluylene diisocyanate, xylylene diisocyanate, hydrogenated xylylene diisocyanate, tetramethylxylylene diisocyanate, 1,5-naphthylene diisocyanate, diphenylene methane-2,4'- and / or -4,4'-diisocyanate, triphenylmethane-4,4',4"-triisocyanate, bis- and tris-(isocyanatoalkyl)-benzene, -toluene and -xylene, and mixtures thereof.

10. Multi-component resin system according to any of claims 1 to 8, characterized in that the isocyanate component comprises at least one aliphatic polyisocyanate selected from the group consisting of hexamethylene diisocyanate (HDI), trimethyl HDI (TMDI), pentane diisocyanate (PDI) 2-methylpentane-1,5-diisocyanate (MPDI), isophorone diisocyanate (IPDI), 1,3- and 1,4-bis(isocyanatomethyl)cyclohexane (H6XDI), bis(isocyanatomethyl)norbornane (NBDI), 3(4)-isocyanatomethyl-1-methyl-cyclohexyl isocyanate (IMCI) and 4,4'-bis(isocyanatocyclohexyl)methane (H12MDI), and mixtures thereof.

11. Multi-component resin system according to any of the preceding claims, characterized in that the total filling level is in a range from 35 to 65 wt.%, based on the total weight of the multi-component resin system.

12. Multi-component resin system according to any of the preceding claims, characterized in that the amine which is reactive to isocyanate groups is selected from the group consisting of 4,4'-methylene-bis[N-(1-methylpropyl)phenylamine], an isomer mixture of 6-methyl-2,4-bis(methylthio)phenylene-1,3-diamine and 2-methyl-4,6-bis(methylthio)phenylene-1,3-diamine, 4,4'-methylenebis(2,6-diethylaniline), 4,4'-methylenebis(N-sec-butylcyclohexanamine), 3,3'-diaminodiphenylsulfone, N,N'-di-sec-butyl-p-phenylenediamine and 2,4,6-trimethyl-m-phenylenediamine, and mixtures thereof.

13. Multi-component resin system according to any of the preceding claims, characterized in that the multi-component resin system is a two-component resin system.

14. Mortar composition produced by mixing the isocyanate component and the amine component of the multi-component resin system according to any of the preceding claims.

15. Method for the chemical fastening of construction elements in boreholes, wherein a multi-component resin system according to any of claims 1 to 13 or a mortar composition according to claim 14 is used for the chemical fastening.

16. Use of a molecular sieve in a multi-component resin system for chemical fastening based on an isocyanate amine adduct, which comprises an isocyanate component and an amine component, in order to improve the storage stability of the isocyanate component.