PREPARATION COMPRISING A HYDRAULIC BINDING AGENT AND A CELLULOSE ETHER

Abstract

The invention relates to a preparation comprising at least one hydraulic binding agent and at least one cellulose ether selected from methylhydroxyethylhydroxypropylcellulose (MHEHPC) and the use thereof, in particular in building material systems.

Claims

1. Preparation comprising (i) at least one hydraulic binding agent, (ii) at least one cellulose ether selected from methylhydroxyethylhydroxypropylcellulose (MHEHPC), (iii) optionally at least one filler, (iv) optionally at least one additive, and (v) optionally water.

2. Preparation according to claim 1, wherein the hydraulic binding agent is selected from cement and hydraulic lime, e.g. CaO, preferably cement.

3. Preparation according to claim 1, wherein the methylhydroxyethylhydroxypropylcellulose (MHEHPC) has an average degree of substitution DS.sub.Methyl of 1.2-2.35, preferably 1.5-2.25, particularly preferably 1.7-2.15, very particularly preferably 1.75-2.0; and/or wherein the at least one cellulose ether selected from methylhydroxyethylhydroxypropylcellulose (MHEHPC) has a molecular degree of substitution MS.sub.Hydroxyethyl of 0.1 to 0.99, preferably 0.15 to 0.8, particularly preferably 0.25-0.6, most preferably 0.2-0.5; and/or wherein the at least one cellulose ether selected from methylhydroxyethylhydroxypropylcellulose (MHEHPC) has a molecular degree of substitution MS.sub.Hydroxypropyl of 0.1 to 0.99, preferably 0.15 to 0.8, particularly preferably 0.25-0.6, most preferably 0.3-0.5.

4. Preparation according to claim 1, wherein the at least one cellulose ether selected from methylhydroxyethylhydroxypropylcellulose (MHEHPC) has an average degree of substitution DS.sub.Methyl of 1.2-2.35, preferably 1.5-2.25, particularly preferably 1.7-2.15, most preferably 1.75-2.0, has a molecular degree of substitution MS.sub.Hydroxyethyl of 0.1 to 0.99, preferably 0.15 to 0.8, particularly preferably 0.25-0.6, most preferably 0.3-0.5.

5. Preparation according to claim 1, wherein the at least one cellulose ether selected from methylhydroxyethylhydroxypropylcellulose (MHEHPC) has a water solubility of at least 2 g/L water at 20° C.

6. Preparation according to claim 1, wherein the proportion of component (ii) is 0.05-0.6% by weight, preferably 0.1-0.5% by weight, most preferably 0.3-0.4% by weight, based on the total mass of components (i) and (ii).

7. Preparation according to claim 1, wherein the at least one filler is selected from gravel, quartz sand, limestone powder and/or synthetic fillers.

8. Preparation according to claim 1, wherein the proportion of component (iii) is preferably 35-70% by weight based on the total weight of components (i), (ii), (iii) and optionally (iv).

9. Preparation according to claim 1, wherein the at least one additive is selected from dispersion powder, inorganic thickener, hardening accelerator, setting retarder, polymer, defoaming agent, air entraining agent, flow agent, hydrophobizing agent and/or fibers.

10. Preparation according to claim 1, wherein the proportion of component (iv) is preferably 1-5% by weight based on the total mass of components (i), (ii), (iv) and optionally (iii).

11. Preparation according to claim 1, wherein the proportion of component (v) is 18-32% by weight, preferably 22-28% by weight, based on the total mass of components (i) and (v).

12. Preparation according to claim 1, wherein the preparation is a dry mortar, tile adhesive, plaster system, a putty, grout and/or masonry mortar.

13. A formulation comprising at least one binding agent and at least one cellulose ether selected from methylhydroxyethylhydroxypropylcellulose (MHEHPC).

14. The formulation according to claim 13, where the binding agent comprises a hydraulic binding agent and the formulation is a hydraulic mortar system.

15. A method for reducing the bulk density and/or improving the processability of a formulation comprising adding at least one cellulose ether selected from methylhydroxyethylhydroxypropylcellulose (MHEHPC) to the formulation.

16. The formulation according to claim 13, wherein the formulation comprises a cementitious mortar system, a tile adhesive, a plaster system, a putty, a grout, or a masonry mortar.

Description

EXAMPLES

[0051] Composition of Tile Adhesive Mixtures:

[0052] In the following, percentages are to be understood as % by weight, unless otherwise stated or evident from the context. “atro” means “absolutely dry”.

[0053] For the production of the different tile adhesive mixtures (hereinafter referred to as FK), the following cellulose ethers (hereinafter referred to as CE) are used with the specifications as indicated below:

[0054] CE1: [0055] Tylose MHEHPC—Methylhydroxyethylhydroxypropylcellulose [0056] DS.sub.Methyl 1.8; MS.sub.Hydroxyethyl 0.4; MS.sub.Hydroxypropyl 0.4 [0057] viscosity 12000-18000 mPa.Math.s (1.9% atro, 20° C., 20° dH, Brookfield RV, spindle 5) [0058] fine powder (air jet sieve, <0.125 mm: 95%, <0.063 mm: 50%)

[0059] CE2: [0060] Tylose MHF 15000 P4—Methylhydroxyethylcellulose [0061] DS.sub.Methyl 1.7; MS.sub.Hydroxyethyl 0.2 [0062] viscosity 11000-15000 mPa.Math.s (1.9% atro, 20° C., 20° dH, Brookfield RV, spindle 5) [0063] fine powder (air jet sieve, <0.125 mm: 90%, <0.100 mm: 70%)

[0064] CE 3: [0065] Tylose MHEHPC—Methylhydroxyethylhydroxypropylcellulose (modified with polyacrylamide and starch ether) [0066] DS.sub.Methyl 1.8; MS.sub.Hydroxyethyl 0.4; MS.sub.Hydroxypropyl 0.4 [0067] viscosity 12000-18000 mPa.Math.s (1.9% atro, 20° C., 20° dH, Brookfield RV, spindle 5)

[0068] CE 4: [0069] Tylose MHF 20010 P4—Methylhydroxyethylcellulose (modified with polyacrylamide and starch ether) [0070] DS.sub.Methyl 1.7; MS.sub.Hydroxyethyl 0.2 [0071] viscosity 16000-21000 mPa.Math.s (1.9% atro, 20° C., 20° dH, Brookfield RV, spindle 5)

[0072] The cellulose ethers CE 3 and CE 4 contain small amounts of polyacrylamide and starch ether which are added by physical mixing.

[0073] The composition of the tile adhesive mixtures is shown in the following table. The indicated numbers represent parts by weight of the individual components in the tile adhesive mixture.

[0074] The water content had to be increased from 26 parts by weight to 28 parts by weight due to the additives in CE 3 and CE 4.

[0075] Test Formulations

TABLE-US-00001 TABLE 1 Compositions of the test mixtures (parts by weight). Test mixture FK 1 FK 2 FK 3 FK 4 Cement CEM I 52.5N 38 38 38 38 Limestone powder 0.1 mm 5 5 5 5 Quartz sand 0.1-0.5 mm 57 57 57 57 Dispersion powder 1 1 CE 1 0.4 CE 2 0.4 CE 3 0.4 CE 4 0.4 water 26 26 28 28

[0076] The following table shows the fresh mortar bulk densities of the various tile adhesive compositions.

TABLE-US-00002 TABLE 2 Fresh mortar bulk densities in kg/L of the different test formulations. Fresh mortar bulk densities as measured: FK 1 FK 2 FK 3 FK 4 directly 1.31 1.40 1.35 1.49 after 30 min 1.34 1.42 1.38 1.53 after 60 min 1.36 1.44 1.41 1.54

[0077] The fresh mortar bulk density was measured directly, after 30 min and after 60 min resting time. Table 2 clearly shows the lower fresh mortar bulk density of the test mixture with MHEHPC (FK 1) compared to the test mixture with Tylose MHF 15000 P4 (FK 2). Even after the addition of additives, MHEHPC leads to lower fresh mortar densities of the test mixture (FK 3) than Tylose MHF 20010 P4 (FK 4). This is accompanied by a very easy processability with mousse-like consistency of the tile adhesive compositions containing MHEHPC.

[0078] Test Methods for Tile Adhesives

[0079] The tile adhesives as described in Table 1 were mixed with water to form a mortar, wherein 100 parts by weight of the formulations described were mixed with 26 parts by weight of mixing water for the tests with CE 1 and CE 2 and 28 parts by weight of mixing water for the tests with CE 3 and CE 4.

[0080] First, the mixtures were stirred for 30 seconds at the lowest level, then allowed to mature for 1 minute, stirred again for 1 minute, allowed to mature for 5 minutes, and finally sheared again for 15 seconds at the lowest level. The mortar was then applied to a concrete slab using a notched trowel (according to ISO 13007). Wetting was measured by placing stoneware tiles (5×5 cm) in the mortar bed after 10, 15, 20, 25 and 30 minutes following application of the mortar (open wetting time), weighting them with 2 kg for 30 seconds and then picking them up from the mortar bed. Table 3 shows the wetting results.

TABLE-US-00003 TABLE 3 Wetting of the back of the tiles in % according to DIN EN 12004 of the different test formulations. Wetting open time FK 1 FK 2 FK 3 FK 4 after 10 min 90 60 90 90 after 15 min 80 50 90 80 after 20 min 60 30 80 70 after 25 min 50 10 70 60 after 30 min 10 60 40

[0081] The wetting degree of FK 1 or FK 3 is higher than the wetting degree of FK 2 or FK 4. MHEHPC thus leads to a slightly better wetting than MHEC.

[0082] The wetting degree of FK 1 or FK 2 is lower than the wetting degree of FK 3 or FK 4. The addition of the dispersion powder and the additives thus leads to an improvement in wetting.

[0083] The adhesive strength after a specific open time for tile adhesives is determined according to DIN EN 12004 by applying the tile adhesive to a defined concrete slab (here Solana) by means of a notched trowel. After 10, 20 and 30 minutes open time after application of the mortar, 4-8 stoneware tiles per time unit are placed in the mortar bed and weighted down with a 2 kg weight for 30 seconds. The stoneware tiles are then stored for 28 days in a standard climate (23° C. and 50% humidity). After storage, the tensile adhesive strength values are determined by tearing the tiles from the concrete slab using a tensile bond strength tester (Herion). The determined values are listed in Table 4.

[0084] The adhesive strength for different storage types according to DIN EN 12004 was also determined. The values listed in Table 4 represent the adhesive tensile strength values after dry storage or standard storage (28 days at 23° C. and 50% humidity), warm storage (14 days standard climate, 14 days at 70° C.) and water immersion (1 week standard climate, three weeks in standard temperature water).

TABLE-US-00004 TABLE 4 Adhesion strengths in N/mm.sup.2 according to DIN EN 12004 of the different test formulations. FK 1 FK 2 FK 3 FK 4 Open time according to ISO 12004 10 min 0.96 0.81 0.90 1.16 20 min 0.51 0.51 0.97 0.94 30 min 0.17 0.26 0.79 0.53 Storage types according to DIN EN 12004 Standard 1.29 1.03 0.68 0.66 Water 1.05 1.19 1.00 0.79 Warm 1.05 0.94 0.56 0.53 Frost/dew 1.45 1.54 0.85 0.61

[0085] The adhesive strengths of the test mixtures FK 1 and FK 2 in relation to the open time are comparable, taking into account the fault tolerance of ±0.2 N/mm.sup.2. The use of CE 1 (MHEHPC) and CE 2 (MHEC) in the test mixtures therefore leads to comparable adhesive strengths. Due to the addition of dispersion powder and additives, the adhesive strengths are higher overall in relation to the open time. FK 3 (MHEHPC) even exceeds the adhesive strength of FK 4 (MHEC) after 30 minutes open time.

[0086] With regard to the different storage types, there are again no significant differences in adhesive strength for FK 1 and FK 2 when the fault tolerance of ±0.2 N/mm.sup.2 is taken into account. The same applies after addition of the dispersion powder and the additives for FK 3 and FK 4, whereby higher overall adhesive strengths are achieved for the test compound with MHEHPC even when taking the fault tolerance into account.

[0087] Conclusion:

[0088] By using MHEHPC, the raw mortar density can be reduced and therefore a light and mousse-like consistency can be achieved, which facilitates the processing of hydraulically setting building materials. This is all the more remarkable as the adhesive strength values are comparable to those described in the prior art.

[0089] The following items are comprised by the present invention:

[0090] 1. Preparation comprising.

[0091] (i) at least one hydraulic binding agent,

[0092] (ii) at least one cellulose ether selected from methylhydroxyethylhydroxypropylcellulose (MHEHPC),

[0093] (iii) optionally at least one filler,

[0094] (iv) optionally at least one additive, and

[0095] (v) optionally water.

[0096] 2. Preparation according to item 1, wherein the hydraulic binding agent is selected from cement and hydraulic lime, preferably cement.

[0097] 3. Preparation according to item 2, wherein the cement is selected from the group consisting of CEM I, CEM II/A-S, CEM II/B-S, CEM II/A-D, CEM II/A-P, CEM II/B-P, CEM II/A-Q, CEM II/B-Q, CEM II/A-V, CEM II/B-V, CEM II/A-W, CEM II/B-W, CEM II/A-T, CEM II/B-T, CEM II/A-L, CEM II/B-L, CEM II/A-LL, CEM II/B-LL, CEM II/A-M, CEM II/B-M, CEM III/A, CEM III/B, CEM III/C, CEM IV/A, CEM IV/B, CEM V/A and/or CEM V/B.

[0098] 4. Preparation according to item 3, wherein the cement has a strength class according to DIN EN 197-1 of 32.5, 42.5 or 52.5.

[0099] 5. Preparation according to item 3 or 4, wherein the cement has an initial strength according to DIN EN 197-1 of N, R or L.

[0100] 6. Preparation according to item 2, wherein the hydraulic lime comprises CaO.

[0101] 7. Preparation according to any one of items 1-7, wherein the at least one cellulose ether selected from methylhydroxyethylhydroxypropylcellulose (MHEHPC) has an average degree of substitution DS.sub.Methyl of 1.2-2.35, preferably 1.5-2.25, particularly preferably 1.7-2.15, most preferably 1.75-2.0.

[0102] 8. Preparation according to any one of items 1-7, wherein the at least one cellulose ether selected from methylhydroxyethylhydroxypropylcellulose (MHEHPC) has a molecular degree of substitution MS.sub.Hydroxyethyl of 0.1-0.99, preferably 0.15-0.8, more preferably 0.25-0.6, most preferably 0.2-0.5.

[0103] 9. Preparation according to any one of items 1-8, wherein the at least one cellulose ether selected from methylhydroxyethylhydroxypropylcellulose (MHEHPC) has a molecular degree of substitution MS.sub.Hydroxypropyl of 0.1 to 0.99, preferably 0.15 to 0.8, particularly preferably 0.25-0.6, most preferably 0.3-0.5.

[0104] 10. Preparation according to any one of items 1-10, wherein the at least one cellulose ether selected from methylhydroxyethylhydroxypropylcellulose (MHEHPC) has an average degree of substitution DS.sub.Methyl of 1.2-2.35, preferably 1.5-2.25, particularly preferably 1.7-2.15, most preferably 1.75-2.0, has a molecular degree of substitution MS.sub.Hydroxyethyl of 0.1 to 0.99, preferably 0.15 to 0.8, particularly preferably 0.25-0.6, most preferably 0.2-0.5, and has a molecular degree of substitution MS.sub.Hydroxypropyl of 0.1 to 0.99, preferably 0.15 to 0.8, particularly preferably 0.25-0.6, most preferably 0.3-0.5.

[0105] 11. Preparation according to any one of the preceding items, wherein the at least one cellulose ether selected from methylhydroxyethylhydroxypropylcellulose (MHEHPC) has a weight average degree of polymerization (DPw) of 1 to 6000, preferably 1 to 5000, measured according to ISO 5351:2010.

[0106] 12. Preparation according to any one of the preceding items, wherein the at least one cellulose ether selected from methylhydroxyethylhydroxypropylcellulose (MHEHPC) has a water solubility of at least 2 g/L water at 20° C.

[0107] 13. Preparation according to any one of the preceding items, wherein component (ii) has a viscosity of 1 to 70,000 mPa.Math.s, preferably 100 to 15,000 mPa.Math.s, more preferably 1000 to 12,000 mPa.Math.s (according to DIN 53015:2019-06; measured in an aqueous solution containing 1.9% by weight of component (ii) based on the total weight of the solution at 20° C. and 20° dH).

[0108] 14. Preparation according to any one of the preceding items, wherein the proportion of component (ii) is 0.05-0.6% by weight, preferably 0.1-0.5% by weight, most preferably 0.3-0.4% by weight, based on the total mass of components (i) and (ii).

[0109] 15. Preparation according to any one of the preceding items, wherein the at least one filler is selected from gravel, quartz sand, limestone powder and/or synthetic fillers.

[0110] 16. Preparation according to any one of the preceding items, wherein the at least one filler has an average particle size d.sub.50 of 0-3 mm.

[0111] 17. Preparation according to any one of the preceding items, wherein the proportion of component (iii) is 5-85% by weight, preferably 35-70% by weight, based on the total weight of components (i), (ii), (iii) and optionally (iv).

[0112] 18. Preparation according to any one of the preceding items, wherein the at least one additive is selected from dispersion powder, inorganic thickener, hardening accelerator, setting retarder, polymer, defoaming agent, air entraining agent, flow agent, hydrophobizing agent and/or fibers.

[0113] 19. Preparation according to any one of the preceding items, wherein the proportion of component (iv) is 0-12% by weight, preferably 1-5% by weight, based on the total mass of components (i), (ii), (iv).

[0114] 20. Preparation according to any one of the preceding items, wherein the proportion of component (v) is 18-32% by weight, preferably 22-28% by weight, based on the total mass of components (i) and (v).

[0115] 21. Preparation according to any one of the preceding items, wherein the preparation is a dry mortar, tile adhesive, plaster system, a putty, grout and/or masonry mortar.

[0116] 22. Use of at least one cellulose ether selected from methylhydroxyethylhydroxypropylcellulose (MHEHPC) as an additive to a formulation comprising at least one hydraulic binding agent.

[0117] 23. Use according to item 22, wherein the formulation is selected from hydraulic mortar systems, in particular cementitious mortar systems, in particular for tile adhesives, plaster systems, putties, grouts and/or masonry mortars.

[0118] 24. Use according to any one of items 22 or 23 for reducing the bulk density of the formulation and/or improving the processability.