Reaction Resin Mortar Curable by Frontal Polymerization and Method for Fixing Anchor Rods

Abstract

A reaction resin mortar curable by frontal polymerization contains at least one radically polymerizable compound, at least one thiol-functionalized compound and at least one polymerization initiator, wherein the weight ratio of the at least one radically polymerizable compound and the at least one thiol-functionalized compound is in the range of 10:1 to 2:1 and wherein the polymerization initiator is selected from compounds which can be thermally activated and/or thermally released at a temperature of above 30 C. and/or ammonium persulfates which are formed in-situ from at least one organically substituted ammonium salt and at least one inorganic persulfate.

Claims

1-13. (canceled)

14: A method for fixing anchor rods, or rebars in bore holes of different subgrades, said method comprising: introducing a reaction resin mortar into the bore hole, inserting the anchor rod, or the rebar into the bore hole, and triggering the frontal polymerization by heating the reaction resin mortar to a temperature above the reaction temperature of the polymerization initiator or of the polymerization accelerator, wherein the reaction resin mortar is curable by frontal polymerization and comprises (a) at least one radically polymerizable compound. (b) at least one thiol-functionalized compound, and (c) at least one polymerization initiator, wherein a weight ratio of the at least one radically polymerizable compound (a) and the least one thiol-functionalized compound (b) is in the range of 10:1 to 2:1, and wherein the polymerization initiator (c) is selected from compounds which can be thermally released at a temperature of 30 C. and/or ammonium persulfates which are formed in-situ from at least one organically substituted ammonium salt and at least one inorganic persulfate.

15: The method according to claim 14, which is suitable for fixing anchor rods, or rebars in hollow subgrades.

16: The method according to claim 14, wherein the polymerization of the reaction resin mortar is triggered by selective or extensive heating of the surface layer or in the inside the mortar mass.

17: The method according to claim 14, wherein the polymerization of the reaction resin mortar is triggered by the supply of heat via the anchor rod or rebar.

18: The method according to claim 16, wherein the selective or extensive heating takes place with the aid of a flame, a soldering tip, a heating wire, a hot air fan, an induction oven, a flash of light, a laser beam and/or in-situ by a chemical reaction.

19. The method according to claim 14, wherein the reaction resin mortar comprises 10 to 98 wt % of a mixture of the at least one radically polymerizable compound (a) and the at least one thiol-functionalized compound (b).

20. The method according to claim 14, wherein the reaction resin mortar comprises 2 to 30 wt % of the polymerization initiator (c).

21. The method according to claim 14, wherein the reaction resin mortar comprises an ammonium persulfate as the polymerization initiator (c), wherein the at least one organically substituted ammonium salt and the at least one organic persulfate are present separately in a reaction inhibiting manner such that the organically substituted ammonium persulfate is formed only after the mixing thereof.

22. The method according to claim 21, wherein the reaction resin mortar comprises, as an organically substituted ammonium salt, a tri or tetra alkyl, aryl or aryl-alkyl ammonium halide, acetate, (hydrogen)carbonate, (hydrogen)phosphate, (hydrogen)sulfate, (meth)acrylate or mixtures of these compounds.

23. The method according to claim 21, wherein the reaction resin mortar comprises, as an inorganic persulfate, ammonium, potassium or sodium persulfate or mixtures of these compounds.

24. The method according to claim 14, wherein the reaction resin mortar comprises, as the polymerization initiator (c), a peroxide and/or an azo compound, which, optionally in the presence of a polymerization accelerator (d), each have a half-life period t in the range between 1 and 200 minutes at a temperature of 100 C. in chlorobenzene.

25. The method according to claim 14, wherein the reaction resin mortar further comprises a polymerization accelerator (d).

26. The method according to claim 14, wherein the reaction resin mortar further comprises inorganic and/or organic aggregates.

27. The method according to claim 26, wherein the aggregate is selected from fillers and/or additives.

28. The method according to claim 27, wherein the aggregate is contained in the reaction resin mortar in a quantity of up to 60 wt %.

29. The method according to claim 25, wherein the polymerization accelerator (d) is selected from amines, sulfides, thiourea or mercaptans and/or metal compounds.

30. The method according to claim 25, wherein the polymerization accelerator (d) is contained in the reaction resin mortar in a quantity of 0.01 to 1 wt %.

31. The method according to claim 14, wherein the at least one thiol-functionalized compound (b) contains at least two thiol groups.

Description

EXAMPLES

[0074] Measuring the Front Temperature as Well as the Front Speed

[0075] The measurement of the front temperature takes place in a test tube with a diameter of 6 mm. Thermoelements are provided at two measuring points at a suitable distance by means of which the change of the temperature can be measured. The reaction resin mortar to be examined is introduced into the test tube at room temperature (23 C.). The polymerization of the reaction resin mortar is triggered by ignition by means of a soldering iron at approximately 200 C. at one point on the mortar surface. The temperature can be determined at the measuring points. The front speed can be calculated from the quotient of the distance between the two measuring points and the time difference between the temperature peaks.

[0076] The open time is the time period within which the finished mixed reaction resin mortar can be processed at room temperature. In this regard, no open time can be indicated for mortar masses which do not spontaneously cure.

[0077] Measuring the Failure Loads

[0078] In order to determine the failure loads of the cured mass, holes with a diameter of 16 mm and a depth of 85 mm are drilled in hollow bricks analogous to EN 791-1, but with a compressive strength of approximately 35 MPa, and HIlti HIT-SC 16*85 screen sleeves (1) are used, as is schematically depicted in FIG. 1, with an insertion end (2) and an open end (3) to fill the screen sleeve (1) with reaction resin mortar and to accommodate the anchor rods, which are lightly wrapped with a resistance wire (resistance value approximately 10 Ohm) (4) according to FIG. 1. After filling the screen sleeves (1) with the reaction resin mortar, threaded anchor rods of the dimension M10 are set and the curing is started by briefly applying a voltage of approx. 12 V via the heating wire (4). The average failure loads are determined by centrically pulling out the threaded anchor rods. Three threaded anchor rods are plugged in, in each case and the load values thereof are determined after two hours of curing.

[0079] The failure loads (kN) determined here are given as mean values in Table 1 below.

Examples 1 to 8

[0080] Reaction resin mortars are manufactured using the constituents indicated in Table 1 below and the front temperatures and the front speeds are determined for the polymerization as well as the failure loads, as described above.

[0081] It is clear from the results that the front temperatures could be in part notably reduced by using the thiol-functionalized compounds, in particular for examples 1 to 8. This leads to reduced foaming and improved curing of the masses. Accordingly, higher failure loads could be achieved with the reaction resin mortars according to the invention than with the reaction resin mortars according to the comparative examples. The results also show that with the compositions according to the invention it is no longer essential for the polymerization front to have to progress at a determined speed in order to achieve sufficient curing of the masses, as in the masses according to DE 100 02 367 C1. It could thus be shown that with the reaction resin mortars according to the invention good curing is no longer dependent on the front speed.

TABLE-US-00001 TABLE 1 Compositions of the reaction resin mortar - Results of the temperature measurement of the polymerization front Comparative Comparative example 1 example 2 Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Example 7 Example 8 TMPTMA.sup.1 10 g 8.9 g 8 g 6.7 g 16 g 8.9 g 13.3 g CN 975.sup.2 10 g 20 g 8.9 g 8 g 6.7 g 2 g 16.5 g 13.3 TMP(EO)TA.sup.3 8.9 g PETMP.sup.4 2.2 g 4 g 6.7 g 2 g 2.2 g 3.3 g 6.7 TMPMP.sup.5 6.7 g Perkadox 20S.sup.6 4 g 4 g 4 g 4 g 4 g TBAPS.sup.7 1.4 g Butyl perbenzoate 1.5 g TMCH.sup.9 1.6 g 1.6 g 1.6 g Octa-Soligen Mn.sup.8 0.2 g Pyrogenic silicic acid 1.2 g 1.2 g 1.2 g 1.2 g 1.2 g 2 g 2 g 1.2 g 1.2 g 1.2 g Ene:Thiol 8:1 4:1 2:1 9:1 8:1 2:1 5:1 2:1 Half-life period t.sub.1/2 at 23 109 23 23 23 56 23 4 109 109 100 C. Temperature [ C.] 223 240 185 165 133 112 125 215 210 195 Open time [min] n/a n/a n/a 120 60 n/a n/a 8 75 45 Front speed [cm/min] 1.3 15 2 1.6 1.4 11 1.7 2.9 8 4 Failure load [kN] M10 * 80 mm 0.5 0.6 1.1 1.9 1.3 2.3 1.2 6.9 1.1 2.4 .sup.1Trimethylolpropane trimethacrylate .sup.2Hexafunctional aromatic urethane acrylate oligomer (Sartomer) .sup.39-fold ethoxylated trimethylolpropane triacrylate .sup.4Pentaerythritol tetra (3-mercaptopropionate) .sup.5Trimethylolpropane tris(3-mercaptopropionate) .sup.620% dibenzoyl peroxide on gypsum basis (AkzoNobel Polymer Chemicals) .sup.7Tetrabutylammonium peroxodisulfate .sup.810% manganese octanoate (OMG Borchers) .sup.91,1-di-(tert-butylperoxy)-3,3,5-trimethylcyclohexane