FREEZE-THAW STABLE QUICK-SET ADDITIVE

Abstract

The present invention provides substantially water free aluminate cement paste compositions that exhibit improved freeze thaw resistance and are storage stable upon being activated on admixture with water or an aqueous liquid. The compositions comprise a deep eutectic solvent mixture of a polar organic carrier component, preferably, glycerol or another hydrogen donor, and an anhydrous cation containing component, such as a metal salt or an onium compound in a paste with an aluminate cement. The compositions can be kept for as long as 30 days or more at room temperature without stabilization and then used to make cementitious coating layers or waterproofing membranes.

Claims

1. A substantially water free aluminate cement paste composition comprises a deep eutectic solvent mixture of a polar organic carrier component in association with an anhydrous cation containing component, and, further, an aluminate cement, wherein the substantially water free aluminate cement paste composition when combined with water or an aqueous liquid to form a hydraulic setting composition provides quick drying and early rain resistance down to temperatures of 5° C.

2. The substantially water free aluminate cement paste composition as claimed in claim 1, wherein the polar organic carrier component of the deep eutectic solvent mixture is a polar protic organic liquid chosen from a hydrogen donor.

3. The substantially water free aluminate cement paste composition as claimed in claim 1, wherein the polar organic carrier component of the deep eutectic solvent mixture is chosen from glycerol, propoxylated glycerols, ethylene glycol, C.sub.3 to C.sub.18 alkane diols, urea, acetamide, 1-methyl urea, 1,3-dimethyl urea, thiourea, benzamide, carboxylic acids, polyols or carbohydrates, oligomers or polymers of a diol, oligomers or polymers of a polyol, oligomers or polymers of an organic acid, oligomers or polymers of a carbohydrate, oligourethanes, polypeptides, or two or more of these.

4. The substantially water free aluminate cement paste composition as claimed in claim 1, wherein the amount of the polar organic carrier component in the deep eutectic solvent mixture ranges from 40 to 99 mol. %, with the remainder comprising the anhydrous cation containing component.

5. The substantially water free aluminate cement paste composition as claimed in claim 1, wherein the anhydrous cation containing component is chosen from non-toxic quaternary ammonium containing materials; ammonium salts, organoammonium salts, simple salts; salts of cyanamide; metal cations combined with non-volatile amines; onium salts; metal cations combined with organic nitrides; metal cations combined with organic sulfonates, metal cations combined with organic sulfonyl group containing compounds, or two or more of these.

6. The substantially water free aluminate cement paste composition as claimed in claim 1, above, wherein the anhydrous cation containing component is chosen from choline chloride (ChCl), (hydroxyethyl) trimethylammonium chloride, ammonium chloride, 1-n-butyl-3-methylimidazolium salts, metal carbonates, semi-metal carbonates, metal halides, semi-metal halides, metal nitrates, metal nitrites, metal sulphates, metal phosphates, metal carbodiimides, salts of cyanamide, metal citrates, metal acetates, non-volatile amines, benzyltriphenylphosphonium halides, metal cations combined with (CF.sub.3CO.sub.2).sub.2N, metal cations combined with trifluoromethanesulfonate, metal cations combined with bis(trifluoromethanesulfonyl) imide, metal cations combined with tris(trifluoromethanesulphonyl) methide, or two or more of any of these.

7. The substantially water free aluminate cement paste composition as claimed in claim 1, wherein the deep eutectic solvent mixture comprises K.sub.2CO.sub.3 and glycerol in a molar ratio of from 1:1 to 1:6, K.sub.2CO.sub.3 and ethylene glycol in a molar ratio of from 1:3 to 1:8, or K.sub.2CO.sub.3 and propoxylated glycerol in molar ratios of from 1:14 to 1:30.

8. The substantially water free aluminate cement paste composition as claimed in claim 1, wherein the amount of the deep eutectic solvent mixture ranges from 20 to 95 wt. %, based on the total weight of the composition.

9. A hydraulic setting aluminate composition comprising the substantially water free aluminate cement paste composition as claimed in claim 1 in combination with an aqueous coating composition.

Description

EXAMPLES

[0093] The following examples are used to illustrate the present invention without limiting it to those examples. Unless otherwise indicated, all temperatures are ambient temperatures (21-23° C.) and all pressures are 1 atmosphere.

[0094] Materials used in the Examples, below, include the following materials:

[0095] Calcium aluminate cement 1 or CAC 1: Calcium aluminate cement (Calcium aluminate solids content: >90% (92 to 98%)), HiPercem™ cement (Calucem, Mannheim, DE);

[0096] Calcium aluminate cement 2 or CAC 2: Ternal™ white cement (calcium aluminate solids content: 97 to 99.7%) (Imerys (Kerneos), Paris, FR);

[0097] Calcium aluminate cement 3 or CAC 3: EXALT™ Calcium aluminate (Kerneos, Paris, FR). Solids: Aluminate content 67 wt. %, stabilized with phosphoric acid 270 mmole/L to give a pH of 5 to 7 in water at 60 wt. % solids;

Examples 1 and 2 and Comparative Examples 1 and 2: Cement Paste Preparation and Storage

[0098] As shown in Table 1, below, in Examples 1 and 2, a deep eutectic solvent mixture was prepared from K.sub.2(CO).sub.3 (40 g) dissolved in glycerol (192 g), at 90° C. by mixing for four (4) hours in a mechanical mixer equipped with a magnetic stirrer. To prepare the aluminate cement paste composition, the deep eutectic solvent mixture 45 pbw was mixed with CAC 1-55 pbw and Ca(OH).sub.2 (29 mg per g deep eutectic solvent mixture). If used, a lithium sulfate monohydrate salt was dispersed in 48.5 g of the deep eutectic solvent mixture. Then, the indicated calcium aluminate cement (CAC 1) was mixed in a mechanical mixer at from 60 to 90° C. by adding the cement in ten roughly equal portions, wherein each portion was mixed for one (1) minute and then the resulting product was mixed for 5 more minutes. The ratio of aluminate cement solids to the deep eutectic solvent mixture was 0.55:0.45, by weight.

[0099] The aluminate cement paste compositions indicated in Table 1, below, were used as an activator in Examples 1 and 2, except that in Example 2, the aluminate cement paste composition was kept at −15° C. over 15 hours. In Comparative Example 2, the aluminate cement paste composition comprised a phosphoric acid stabilized aqueous aluminate cement paste composition, CAC 3.

[0100] In each example, an aqueous acrylic styrene emulsion copolymer (Primal™ AS-8012, Dow, MFFT −8° C.) having a solids content of 54.93 wt. % and the aluminate cement paste compositions indicated in Table 1, below, were combined with the remaining materials in Table 2, below, in a mechanical mixer equipped with a polytetrafluoroethylene coated mechanical stirring bar and mixed for 5 minutes.

[0101] In addition, the cementitious basecoat formulation in Comparative Example 2 contained 2 wt. %, based on total cement solids of a PERAMIN™ AXL 80 lithium sulfate monohydrate salt (Kerneos) was added as an activator.

[0102] In all examples, the ratio between cement solids and acrylic emulsion polymer solids was 55:45 (w/w). If the pH was not at 12.5, the pH was adjusted to 12.5 with NaOH 20% (w/w) after activation in all examples. The granular basecoat compositions were applied to a cementitious rendering mortar 2 mm (SM700 Pro, Knauf Gips KG, Iphofen, DE)) as a substrate having a thickness of 2 mm.

[0103] The resulting emulsion copolymer binder containing cementitious coatings were dried under cold, humid (5° C., 50% rH) conditions in the absence (Comp. Ex. 1) or presence of aluminate cement paste compositions (Ex. 1 and 2, Comp. Ex. 2).

[0104] The coatings were then dried for 6 hours at 5° C. and 85% relative humidity, before an early rain-resistance test was performed. In the Early rain resistance test, the dried coatings were exposed to a 30 minute cold water shower (conventional shower head) wherein the water pressure in the tube was 5 bar and the distance from the shower head to the panel was 20 cm.

TABLE-US-00001 TABLE 1 Early Rain Resistance Performance Deep eutectic solvent Aluminate mixture and Aluminate Cement Paste Early rain Example cement paste composition Pretreatment resistance 1 DES (K.sub.2CO.sub.3: Glycerol as None Yes, coating 1:4.8 mol/mol) 45 pbw and intact CAC 1-55 pbw 2 DES (K.sub.2CO.sub.3: Glycerol as −15° C./15 h Yes, coating 1:4.8 mol/mol) 45 pbw and intact CAC 1-55 pbw Comp. 1* None None No, wash-off, no film Comp. 2* CAC 3 None No, wash-off *Denotes Comparative Example.

[0105] As shown in Table 1, above, the paste of inventive Example 1 gave a coating that was dry to the touch after 2 hours while the paste of comparative Example 1 was not dry after 6 hours, demonstrating the accelerating hardening effect of the cement paste. Furthermore, both inventive Examples 1 and 2 passed the early water resistance tests, while the comparative Examples 1 and 2 did not; instead, the coatings washed off.

[0106] In Example 2, the aluminate cement paste composition remained stable, and did not sediment after being kept at −15° C. over 15 hours. So, only the inventive aluminate cement paste compositions of Examples 1 and 2 passed all tests.

TABLE-US-00002 TABLE 2 Composition of coating formulation used in the Table 1 Examples Component Material wt. % Dispersant Polycarboxylate polymer (Orotan ™ 850 ER, Dow, 0.18 Midland, MI) Antifoam Hydrocarbons and surfactants (Foamaster ™ MO 0.04 2134, BASF, Ludwigshaven, DE) Water 10.78 Thickener Cellulose ether (Walocel ™ MW 40000 PFV, Dow) 0.07 Emulsion Acrylic Emulsion co-polymer (Primal ™ AS 8012, 4.63 Copolymer Dow) Extender I Calcium carbonate (CaCO.sub.3) (Durcal ™ 2 Omya, 18.18 Oftringen, CH) Extender II Calcium carbonate (CaCO.sub.3) (Durcal ™ 40 Omya, 10.08 Oftringen, CH) Aggregates Quarzsand (SiO.sub.2) (Carlo Bernasconi Ag, Bern, CH) 14.14 Pigment Iron oxide (Fe.sub.2O.sub.3) (BayferroxTM red 130, 0.74 Lanxess, Cologne, DE) Structural Calcium carbonate (CaCO.sub.3) (OMYACARB ®, 41.18 Granules 2.5-3 mm, Oftringen, CH)

Example Set II: Examples 3 and 4 and Comparatives 3 and 4

[0107] A coating composition was formulated according to Table 3, below, using a mechanical lab mixer (Dispermat™ mixer, Byk, Wallingford, Conn.). After resting for 24 h the aluminate cement paste indicated in Table 4, below, was added to the coating composition. After addition, the mixture was manually homogenized for 3 minutes. The activated coatings were then applied to polystyrene panels coated with an organic, cement free dispersion base coat (Elasto™, Sto AG, Stühlingen, DE) and dried under controlled conditions (80% relative humidity and 7° C.). After 8 hours the panel was vertically exposed to the early rain resistance (ERR) test. Water was sprayed for 15 minutes with an axial-flow full cone nozzle (type 490 404 CA, Lechler GmbH, Metzingen, DE) under a pressure of 2 bar that was placed 30 cm from the sample surface in a 90 degree angle. Results are shown in Table 4, below.

[0108] Dry Tip tests were performed on drying coatings by pressing a paper towel on to the coating each 60 min by hand. If no wet material sticks to the paper the sample is considered to be dry. Results are shown in Table 4, below.

TABLE-US-00003 TABLE 3 Coating formulation composition Material wt % Polycarboxylate polymer (Orotan ™ 850 ER, Dow, 0.31 Midland, MI) Mixtures of paraffin-based mineral oil and hydrophobic 0.06 components, containing silicone (BYK 038, BYK Chemie) Water 15.24 Celulose Ether (Walocel MW 40000 PFV, Dow, 0.12 Midland, MI) Acrylic Emulsion Co-polymer (Acousticryl ™ AV-1420, 8.56 Dow, Midland, MI) Calcium carbonate (CaCO.sub.3) (Durcal ™ 2 Omya, 31.90 Oftringen, CH) Calcium carbonate (CaCO.sub.3) (Durcal ™ 40 Omya, 17.69 Oftringen, CH) Quarzsand (SiO.sub.2) (Carlo Bernasconi Ag, Bern, CH) 24.81 Iron oxide (Fe.sub.2O.sub.3) (Bayferrox ™ red 130, 1.30 Lanxess, Cologne, DE) 100.00

TABLE-US-00004 TABLE 4 Comparison of coating drying and early rain resistance (ERR) of coatings with Aluminate Cement Pastes Coating ERR, 8 h formulation/ Tip Tip Tip at 80% rel Example Aluminate Cement Paste Cement Paste dry, 1 h dry, 2 h dry, 3 h humidity, 7° C. 3 DES (K.sub.2CO.sub.3:Ethylene Glycol as 50 g/5.0 g pass pass pass pass 1:4.8 mol/mol) 35 pbw and CAC 1-65 pbw 4 DES (K.sub.2CO.sub.3:Ethylene Glycol as 50 g/4.2 g pass pass pass pass 1:4.8 mol/mol) 35 pbw and CAC 1-65 pbw Comp. 3* CAC 3 50 g/4.6 g fail fail pass fail Comp. 4* — 50 g/0 g   fail fail pass fail *Denotes Comparative Example

[0109] As shown in Table 4, above, the inventive aluminate cement paste compositions of Examples 3 and 4 passed all tests whereas the Comparative Example 3 stabilized aqueous aluminate cement paste composition needed three hours to pass the tip dry test but still failed the early rain resistant test. The ordinary cement composition of Comparative Example 4 failed all tests.