Curing composition for an epoxy resin compound, epoxy resin compound and multi-component epoxy resin system

Abstract

A curing composition for an epoxy resin compound useful for the chemical fastening of construction elements, an epoxy resin compound, and a multi-component epoxy resin system are provided. A method for the chemical fastening of construction elements in boreholes and a method of using a salt (S) as an accelerator in an epoxy resin compound for chemical fastening, the epoxy resin compound including a Mannich base and an amine which is reactive to epoxy groups.

Claims

1. A multi-component epoxy resin system, comprising: an epoxy resin component (A) and a curing component, wherein the epoxy resin component (A) contains a curable epoxy resin, and the curing component contains at least one Mannich base and at least one amine which is reactive to epoxy groups, wherein the curable epoxy resin is based on one or more of bisphenol A or bisphenol F, wherein the at least one Mannich base is obtainable by reacting a phenolic compound selected from one or more of the group consisting of bisphenol A, bisphenol F, resorcinol, and phenol, with an aldehyde or an aldehyde precursor and an amine having at least two active hydrogen atoms in the molecule which are bonded to a nitrogen atom, and further comprising at least one salt (S) selected from salts of nitric acid, or salts of trifluoromethanesulfonic acid or combinations thereof contained in the epoxy resin component (A) and/or in the curing component, and wherein the at least one salt (S) comprises a cation other than ammonium or other than an ammonium cation substituted with an organic group, and wherein the at least one amine which is reactive to epoxy groups is selected from the group consisting of one or more selected from one or more of the group consisting of mXDA (m-xylylenediamine), IPDA (3-aminomethyl-3,5,5-trimethylcyclohexane), Dytek A (2-methylpentanediamine), TMD (1,6-diamino-2,2,4-trimethylhexane), N-EAP (N-ethylaminopiperazine), MCDA (methylcyclohexyl diamine), and 1,3-BAC (1,3-bis(aminomethyl)cyclohexane).

2. The multi-component epoxy resin system according to claim 1, wherein the at least one salt (S) comprises a cation selected from the group consisting of alkali metals, alkaline earth metals, lanthanoids, aluminum, and combinations thereof.

3. The multi-component epoxy resin system according to claim 1, wherein the aldehyde is an aliphatic aldehyde, and wherein the aldehyde precursor comprises trioxane or paraformaldehyde.

4. The multi-component epoxy resin system according to claim 1, wherein the at least one salt (S) is present in a proportion of from 0.1 to 15 wt. %, based on total weight of the curing composition.

5. The multi-component epoxy resin system according to claim 1, wherein the at least one salt (S) is contained in the curing component.

6. The multi-component epoxy resin system according to claim 1, wherein the aldehyde is formaldehyde and wherein the aldehyde precursor comprises trioxane or paraformaldehyde.

7. A method for the chemical fastening of construction elements in boreholes, the method comprising: chemical fastening of the construction elements with a multi-component epoxy resin system according to claim 1.

8. A cured compound prepared by curing the multi-component epoxy resin system according to claim 1.

9. The multi-component epoxy resin system according to claim 1, wherein the at least one salt (S) comprises calcium triflate or calcium nitrate, and wherein the at least one salt (S) is present in a proportion of from 1.0 to 10 wt. %, based on total weight of the curing composition.

10. The multi-component epoxy resin system according to claim 1, wherein the salt is a triflate.

11. The multi-component epoxy resin system according to claim 1, wherein the salt is a nitrate.

12. The multi-component epoxy resin system according to claim 1, wherein the at least one salt (S) is other than a triflate of magnesium, calcium, zinc, or tin.

Description

EXAMPLES

(1) Epoxy Resin Component (A)

(2) Starting Materials

(3) In the examples, the bisphenol A-based and bisphenol F-based epoxy resins commercially available under the names Araldite GY 240 and Araldite 282 (Huntsman), respectively, were used as the epoxy resins.

(4) The 1,4-butanediol-diglycidyl ether and trimethylpropane-triglycidyl ether commercially available under the names Araldite DY-026 and Araldite™ DY-T (Huntsman), respectively, were used as reactive diluents.

(5) 3-glycidyloxypropyl-trimethoxysysilane available under the name Dynalsylan GLYMO™ (Evonik Industries) was used as the adhesion promoter.

(6) The liquid components were premixed by hand. Subsequently, quartz (Millisil™ W12 from Quarzwerke Frechen) was added as a filler and fumed silica (Cab-O-Sil™ TS-720 from Cabot Rheinfelden) was added as a thickener and the mixture was stirred in a dissolver (PC laboratory system, volume 1 L) for 10 minutes at a negative pressure of 80 mbar at 3500 rpm.

(7) The composition of the epoxy resin components A used in the examples is given in table 1 below.

(8) TABLE-US-00001 TABLE 1 Composition of the epoxy resin component A in wt. % (EEW 255 g/EQ) Substance Function Wt. % 3-glycidyloxypropyltrimethoxysilane Adhesion promoter 2.8 Bisphenol A-based epoxy resin Epoxy resin 31.4 Bisphenol F-based epoxy resin Epoxy resin 16.7 1,4-butanediol-diglycidyl ether Reactive diluent 6.0 Trimethyolpropane-triglycidyl ether Reactive diluent 6.0 Quartz Filler 34.4 Silicic acid Thickener 2.7
Curing Composition (B)

(9) The Mannich bases commercially available under the name Epikure Curing Agent 132 (mXDA-bisphenol A-based Mannich base in mXDA from Momentive Specialty Chemicals, NL) were used as Mannich bases. Furthermore, a mXDA-resorcinol-based Mannich base in mXDA, an mXDA-phenol-based Mannich base in mXDA and an IPDA-phenol-based Mannich base in IPDA were prepared. Methods for preparing the Mannich bases are described in EP0645408 A1.

(10) m-xylylenediamine (mXDA) and 1,3-cyclohexanedimethanamine (1,3-BAC) from Mitsubishi Gas Chemical, Japan, and isophorone diamine (IPDA) from Evonik Degussa, Germany, were used as amines for the preparation of the curing composition (B).

(11) 3-aminopropyl-triethoxysilane, which is available under the trade name Dynasylan AMEO from Evonik Degussa, was used as an adhesion promoter.

(12) Quartz (Millisil™ W12 from Quarzwerke Frechen) and calcium aluminate cement (Secar 80 from Kerneos SA) were used as a filler and fumed silica (Cab-O-Sil™ TS-720 from Cabot Rheinfelden) was used as a thickener.

(13) The constituents given in table 2 below were used to prepare the salts (S) used in the curing composition B.

(14) TABLE-US-00002 TABLE 2 Salts (S) used as accelerators Salt (S) Trade name Manufacturer Calcium nitrate Calcium nitrate tetrahydrate Sigma-Aldrich Sodium iodide Sodium iodide Sigma-Aldrich Calcium triflate Calcium Sigma-Aldrich trifluoromethanesulfonate

(15) The salts calcium nitrate and sodium iodide were used as solutions in glycerol (1,2,3-propanetriol, CAS No. 56-81-5, Merck. D). To prepare the calcium nitrate solution, 400.0 g calcium nitrate tetrahydrate was added to 100.0 g glycerol and stirred at 50° C. until completely dissolved (3 hours). The solution prepared in this way contained 80.0% calcium nitrate tetrahydrate. To prepare the sodium iodide solution, 36.4 g sodium iodide was added to 63.6 g glycerol and stirred until completely dissolved. The solution prepared in this way contained 36.4% sodium iodide.

(16) Calcium triflate was dissolved as a solid in the amine of the particular curing agent.

Examples 1 to 8

(17) The liquid components were mixed to prepare the curing compositions (B). The accelerator was added and quartz powder and silicic acid were then added and stirred in a dissolver (PC laboratory system, volume 1 L) for 10 minutes at a negative pressure of 80 mbar at 3500 rpm.

(18) The composition of the curing compositions (B) prepared in this way is given in table 3 below:

(19) TABLE-US-00003 TABLE 3 Composition of the curing compositions (B) in wt. % (examples 1 to 10) Example 1 2 3 4 5 6 7 8 9 10 Mannich mXDA-resorcinol- 54.2 55.0 49.7 — — — — — — — base/ based Mannich amine base/mXDA mXDA-bisphenol — — — 54.2 55.0 49.7 — — — — A-based Mannich base/mXDA mXDA-phenol- — — — — — — 40.0 38.0 — — based Mannich base/mXDA IPDA-phenol- — — — — — — — — 40.0 38.0 based Mannich base/IPDA Amine mXDA — — — — — — 14.2 — — — IPDA — — — — — — — 13.7 — 13.7 1,3-BAC — — — — — — — 13.0 — Salt (S) Calcium nitrate 3.8 — — 3.8 — — 3.8 6.3 5.0 6.3 Sodium iodide — — 8.3 — — 8.3 — — — — Calcium triflate — 3.0 — — 3.0 — — — — — Adhesion 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 promoter Quartz 37.3 37.3 37.3 37.3 37.3 37.3 37.3 37.3 37.3 37.3 Thickener 2.7 2.7 2.7 2.7 2.7 2.7 2.7 2.7 2.7 2.7 AHEW [g/Eq] 87 86 95 96 95 105 98 111 94 102

Comparative Examples 1 and 3

(20) The liquid components were mixed to prepare the curing compositions (B) of the comparative examples. The accelerator was added and quartz powder and silicic acid were then added and stirred in a dissolver (PC laboratory system, volume 1 L) for 10 minutes at a negative pressure of 80 mbar at 3500 rpm. The commercially available accelerator Ancamin K54 (2,4,6-tris(dimethylaminomethyl)phenol, bis[(dimethylamino)methyl]phenol) from Evonik was used as the accelerator.

(21) The composition of the curing compositions (B) prepared in this way is given in table 4 below:

(22) TABLE-US-00004 TABLE 4 Composition of the curing compositions (B) in wt. % (comparative examples 1 to 7) Example 1 2 3 4 5 6 7 Mannich mxDA-resorcinol-based 55.0 — — — — — — base/amine Mannich base/mXDA mxDA-bisphenol A-based — 55.0 — — — — — Mannich base/mXDA mxDA-phenol-based Mannich — — 40.0 40.0 — — — base/mXDA IPDA-phenol-based Mannich — — — — 40.0 40.0 — base/IPDA Amine mXDA — — 15.0 — — — 41.2 IPDA — — — 15.0 — 15.0 — 1,3-BAC — — — — 15.0 — Accelerator Ancamin K54 3.0 3.0 3.0 3.0 3.0 3.0 — Calcium nitrate — — — — — — 3.8 Adhesion promoter 2.0 2.0 2.0 2.0 2.0 2.0 — Quartz 37.3 37.3 37.3 37.3 37.3 37.3 25.0 Thickener 2.7 2.7 2.7 2.7 2.7 2.7 5.0 Calcium aluminate cement — — — — — — 25.0 AHEW [g/Eq] 86 95 95 104 89 95 83
Mortar Compounds and Pull-Out Tests

(23) The epoxy resin component (A) and the curing composition (B) were mixed in a speed mixer in a ratio resulting in a balanced stoichiometry according to the EEW and AHEW values. The mixture was poured into a one-component cartridge as far as possible without bubbles, and was immediately injected into the borehole made for the pull-out tests.

(24) The pull-out strength of the mortar compounds obtained by mixing the epoxy resin component (A) and curing composition (B) according to the above examples was determined using a high-strength anchor threaded rod M12 according to ETAG 001 Part 5, which was doweled into a hammer-drilled borehole having a diameter of 14 mm and a borehole depth of 69 mm by means of the relevant mortar compound in C20/25 concrete. The boreholes were cleaned by means of compressed air (2×6 bar), a wire brush (2×) and again by compressed air (2×6 bar).

(25) The boreholes were filled up, by two thirds from the bottom of the borehole, with the mortar compound to be tested in each case. The threaded rod was pushed in by hand. The excess mortar was removed using a spatula.

(26) The curing time in test 1 was 4 h at 21° C. In test 2, the curing time was 6 hours at 21° C. In test 3, the curing time was 24 hours at 21° C. In test 4, the curing time was 24 hours at 25° C., followed by storage at 80° C. for 24 hours. The pull-out test was carried out at 80° C.

(27) In test 5 (Fic), the borehole was filled with water after being drilled and cleaned (once by being blown out with compressed air (6 bar), once using a brush and then once again by being blown out with compressed air (6 bar)). The mortar was injected into the water-filled borehole via a mixer extension comprising a piston plug. The curing time of the mortar was 48 hours at 25° C.

(28) The failure load was determined by centrally pulling out the anchor threaded rod with a narrow support. The load values obtained with the mortar compounds using a curing composition (B) according to examples 1 to 8 and comparative examples 1 to 5 are shown in table 5 below.

(29) TABLE-US-00005 TABLE 5 Determination of the load values of examples 1 to 10 according to the invention Pull- Examples out Test 1 2 3 4 5 6 7 8 9 10 tests Number Load value [N/mm.sup.2]  4 h 1 21.8 19.5 17.9 26.2 25.4 23.5 23.5 20.0 18.0 13.3 curing  6 h 2 25.6 27.1 25.5 30.7 29.6 30.8 32.1 28.9 N/A N/A curing 24 h 3 33.6 34.1 33.5 33.9 33.5 33.9 36.1 36.0 38.4 37.7 curing 80° C. 4 N/A N/A N/A N/A NIA N/A N/A N/A 26.5 27.7 F1c 5 22.4 N/A N/A N/A N/A N/A N/A N/A 24.9 24.5

(30) TABLE-US-00006 TABLE 6 Determination of the load values of comparative examples 1 to 7 Comparative example Pull-out Test 1 2 3 4 5 6 7 tests Number Load value [N/mm.sup.2]  4 h curing 1  2.2  7.5  0.7  0.2  0.3  0.0 N/A  6 h curing 2 23.6 28.2 24.6 15.1 N/A N/A N/A 24 h curing 3 34.5 33.1 38.3 35.1 37.4 36.8 38.8 80° C. 4 N/A N/A N/A N/A N/A N/A 23.9 F1c 5 N/A N/A N/A N/A N/A N/A 20.6

(31) The epoxy resin compounds according to the invention comprising curing compositions according to examples 1 to 8 exhibit much faster curing than the epoxy resin compounds comprising the curing compositions from comparative examples 1 to 4. The mortar compounds prepared using the curing compositions according to the invention can be subjected to loading after just 6 h. This makes it possible to considerably reduce the waiting times before the next work step and to allow follow-up work to be carried out much earlier.