POLYMER HAVING POLYETHER SIDE CHAINS

Abstract

The invention relates to a polymer which is obtainable by copolymerizing monomers comprising at least one ethylenically unsaturated monomer which comprises at least one acid group and at least one ethylenically unsaturated monomer (II) having polyether groups with 5 to 35 repeating units and at least one ethylenically unsaturated monomer (III) having polyether groups with 45 to 150 repeating units, the molar ratio of monomer (II) to monomer (III) being between 75:25 and 99.5:0.5. Further disclosed are the use of the polymer of the invention as an admixture for inorganic binder compositions, and a composition in powder form comprising an inorganic binder and the polymer of the invention.

Claims

1. A polymer obtained by copolymerizing monomers comprising (I) at least one ethylenically unsaturated monomer which comprises at least one acid group and (II) at least one ethylenically unsaturated monomer having polyether groups of the structural unit (IIa),
—(C.sub.aH.sub.2aO).sub.n—  (IIa) where n is an integer from 5 to 35, a independently at each occurrence for each (C.sub.aH.sub.2aO) unit identically or differently is 2, 3 or 4, and (III) at least one ethylenically unsaturated monomer having polyether groups of the structural unit (IIIa),
—(C.sub.bH.sub.2bO).sub.m—  (IIIA) where m is an integer from 45 to 150, b independently at each occurrence for each (C.sub.bH.sub.2bO) unit identically or differently is 2, 3 or 4, and where the molar ratio of monomer (II) to monomer (III) is between 75:25 and 99.5:0.5.

2. The polymer according to claim 1, wherein the acid group of the monomer (I) is at least one from the group consisting of carboxyl, phosphono, sulfino, sulfo, sulfamido, sulfoxy, sulfoalkyloxy, sulfinoalkyloxy, and phosphonooxy.

3. The polymer according to claim 1, wherein monomer (II) is represented by the general formula (IIb) ##STR00005## where U is oxygen or a chemical bond, p is an integer between 0 and 4, X is oxygen, sulfur or a group NR.sup.3, k is 0 or 1, W is a hydrogen, a C.sub.1-C.sub.6 alkyl or an aryl radical or is the group Y-F, where Y is a linear or branched alkylene group having 2 to 8 carbons and may carry a phenyl ring, F is a 5- to 10-membered nitrogen heterocycle which is bonded via nitrogen and which as ring members, besides the nitrogen atom and besides carbon atoms, may have 1, 2 or 3 additional heteroatoms selected from oxygen, nitrogen, and sulfur, it being possible for the nitrogen ring members to have a group R.sup.4, and for 1 or 2 carbon ring members to be carbonyl group(s), R.sup.1, R.sup.2, R.sup.3, and R.sup.4 independently of one another are hydrogen or an aliphatic hydrocarbon radical having 1 to 4 carbons, or benzyl, and where n is an integer from 5 to 35, and a independently at each occurrence for each (C.sub.aH2.sub.aO) unit identically or differently is 2 3 or 4.

4. The polymer according to claim 1, wherein monomer (III) is represented by the general formula (IIIb) ##STR00006## where U is oxygen or a chemical bond, p is an integer between 0 and 4, X is oxygen, sulfur or a group NR.sup.3, k is 0 or 1, W is a hydrogen, a C.sub.1-C.sub.6 alkyl or an aryl radical or is the group Y—F, where Y is a linear or branched alkylene group having 2 to 8 carbons and may carry a phenyl ring, F is a 5- to 10-membered nitrogen heterocycle which is bonded via nitrogen and which as ring members, besides the nitrogen atom and besides carbon atoms, may have 1, 2 or 3 additional heteroatoms selected from oxygen, nitrogen, and sulfur, it being possible for the nitrogen ring members to have a group R.sup.4, and for 1 or 2 carbon ring members to be carbonyl group(s), R.sup.3, R.sup.4, R.sup.5, and R.sup.6 independently of one another are hydrogen or an aliphatic hydrocarbon radical having 1 to 4 carbons, or benzyl, and where m is an integer from 45 to 150, b independently at each occurrence for each (C.sub.bH.sub.2bO) unit identically or differently is 2, 3 or 4.

5. The polymer according to claim 3, wherein U is oxygen, p is 4, X is oxygen, k is 0, and R.sup.1, R.sup.2, R.sup.5 and R.sup.6 independently of one another are hydrogen or a methyl group.

6. The polymer according to claim 1, wherein n is an integer from 20 to 30, a independently at each occurrence for each (C.sub.aH.sub.2aO) unit identically or differently is 2 or 3.

7. The polymer according to claim 1, wherein m is an integer from 65 to 75, b independently at each occurrence for each (C.sub.bH.sub.2bO) unit identically or differently is 2 or 3.

8. The polymer according to claim 1, wherein the ethylenically unsaturated monomer (I) is represented by at least one of the following general formulae from the group consisting of (Ia), (Ib), and (Ic) ##STR00007## where R.sup.7 and R.sup.8 independently of one another are hydrogen or an aliphatic hydrocarbon radical having 1 to 20 carbons, B is H, —COOM.sub.a, —CO—O(C.sub.qH.sub.2qO).sub.r—R.sup.9, or —CO—NH—(C.sub.qH.sub.2qO).sub.r—R.sup.9, M is hydrogen, a mono-, di- or trivalent metal cation, ammonium ion or an organic amine radical, a is ⅓, ½ or 1, R.sup.9 is hydrogen, an aliphatic hydrocarbon radical having 1 to 20 carbons, a cycloaliphatic hydrocarbon radical having 5 to 8 carbons, or an optionally substituted aryl radical having 6 to 14 carbons, q independently at each occurrence for each (C.sub.qH.sub.2qO) unit identically or differently is 2, 3 or 4, and r is 0 to 200, Z is O, NR.sup.16, R.sup.16 independently at each occurrence is identical or different and represented by a branched or =branched C.sub.1 to C.sub.10 alkyl radical, C.sub.5 to C.sub.8 cycloalkyl radical, aryl radical, heteroaryl radical or H, ##STR00008## where R.sup.1° and R″ independently of one another are hydrogen or an aliphatic hydrocarbon radical having 1 to 20 carbons, a cycloaliphatic hydrocarbon radical having 5 to 8 carbons, or an optionally substituted aryl radical having 6 to 14 carbons, R.sup.12 is identical or different and represented by (C.sub.nH.sub.2n)—SO.sub.3H with n=0, 1, 2, 3 or 4, (C.sub.nH.sub.2n)—OH with n=0, 1, 2, 3 or 4; (C.sub.nH.sub.2n)—PO.sub.3H.sub.2 with n=0, 1, 2, 3 or 4, (C.sub.nH.sub.2n)—OPO.sub.3H.sub.2 with n=0, 1, 2, 3 or 4, (C.sub.6H.sub.4)—SO.sub.3H, (C.sub.6H.sub.4)—PO.sub.3H.sub.2, (C.sub.6H.sub.4)—OPO.sub.3H.sub.2 or (C.sub.nH.sub.2n)—NR.sup.14.sub.b with n=0, 1, 2, 3 or 4 and b=2 or 3, R.sup.13 is H, —COOM.sub.a, —CO—O(C.sub.qH.sub.2qO).sub.r—R.sup.9, or —CO—NH—(C.sub.qH.sub.2qO).sub.r—R.sup.9, where M.sub.a, R.sup.9, q, and r possess definitions stated above, R.sup.14 is hydrogen, an aliphatic hydrocarbon radical having 1 to 10 carbons, a cycloaliphatic hydrocarbon radical having 5 to 8 carbons, or an optionally substituted aryl radical having 6 to 14 carbons, Q is identical or different and represented by NH, NR.sup.15 or O; where R.sup.15 is an aliphatic hydrocarbon radical having 1 to 10 carbons, a cycloaliphatic hydrocarbon radical having 5 to 8 carbons or an optionally substituted aryl radical having 6 to 14 carbons.

9. The polymer according to claim 1, wherein the polymer is in powder form.

10. The polymer according to claim 1, wherein the ethylenically unsaturated monomer (I) is at least one compound from the group consisting of acrylic acid, methacrylic acid, crotonic acid, itaconic acid, maleic acid, fumaric acid, vinylsulfonic acid, allylsulfonic acid, sulfoethyl methacrylate, 2-acrylamido-2-methyl-propanesulfonic acid (AMPS), 2-methacrylamido-2-methylpropanesulfonic acid, 2-acrylamidobutanesulfonic acid, 3-acrylamido-3-methylbutanesulfonic acid, 2-acrylamido-2,4,4-trimethylpentanesulfonic acid, vinylphosphonic acid, allylphosphonic acid, N-(meth)acrylamidoalkylphosphonic acids, and (meth)acryloyloxyalkylphosphonic acids.

11. The polymer according to claim 1, wherein the fraction of the monomer (I) in the polymer is 50 to 90 mol %.

12. The polymer according to claim 1, wherein the fraction of the monomer (II) and the fraction of the monomer (III) together in the polymer are 10 to 50 mol %.

13. A process of utilizing the polymer according to claim 1 as an admixture for inorganic binder compositions comprising mixing the polymer in powder form with said inorganic binder compositions.

14. A composition in powder form, comprising, based on the total mass of the composition, A) at least 20 wt % of an inorganic binder and B) 0.01 to 4 wt % of at least one polymer according to claim 1.

15. The composition in powder form according to claim 14, which comprises self-leveling calcium sulfate screed.

16. The polymer according to claim 4, wherein U is oxygen, p is 4, X is oxygen, k is 0, and R.sup.1, R.sup.2, R.sup.5 and R.sup.6 independently of one another are hydrogen or a methyl group.

Description

EXAMPLES

[0100] Synthesis of the Dispersants

[0101] A 1 liter four-neck flask with thermometer, reflux condenser, and a connection for two feeds was charged with 540 g of water and a total of 370 g of vinyloxybutyl polyethylene glycol having 22 EO units and/or vinyloxybutyl polyethylene glycol having 65 EO units, in accordance with table 1. 0.01 g of iron(II) sulfate, 1.4 g of mercapto-ethanol, and 8 g of Brüggolit FF6 from Brüggemann GmbH (mixture of sodium sulfite, the disodium salt of 2-hydroxy-2-sulfinatoacetic acid, and the disodium salt of 2-hydroxy-2-sulfonatoacetic acid) were dissolved. The solution was cooled to 13° C. The amount of acrylic acid corresponding to table 1 was added. Then, immediately, 4 g of 50% strength hydrogen peroxide solution were added rapidly. After the end of the exothermic reaction, stirring was continued for 5 minutes and neutralization to a pH of 7 took place using NaOH.

TABLE-US-00001 TABLE 1 VOBPEG VOBPEG 3000 1100 Acrylic acid Charge (molar (molar (molar density Experiment fractions) fractions) fractions) [meq/g]  1 0.1 0.9 3 0.4  2 0.2 0.8 3 0.46  3 0.1 0.9 3.5 0.34  4 0.2 0.8 4 0.35  5 0.05 0.95 3 0.36  6 0.15 0.85 3.5 0.37  7 (comparative) 0 1 3 0.33  8 (comparative) 1 0 9 0.33  9 (comparative) 0.4 0.6 5 0.36 10 (comparative) 0.3 0.7 5 0.32 11 (comparative) 0.4 0.6 3 0.6 12 (comparative) 0.3 0.7 3 0.53 VOBPEG 3000: vinyloxybutyl polyethylene glycol having 65 EO units VOBPEG 1000: vinyloxybutyl polyethylene glycol having 22 EO units

[0102] Powder Quality

[0103] The powder quality was determined by means of DSC (differential scanning calorimetry) (heating/cooling rate 5 K/min). The factor determining powder quality and stability selected is the melting point. As a qualitative assessment, a mortar test was employed. Here, the powder was heated to 40° C. in a mortar and then ground with the pestle for 30 seconds under constant pressure. If the material retained its powder form, the powder stability was evaluated as “++”; if it altered its appearance only slightly, it was evaluated as “+”. If substantial agglomerates were formed, an evaluation of “−” was awarded. The results are set out in table 2.

TABLE-US-00002 TABLE 2 Melting point Dispersant [° C.] Rating  1 35 +  2 40 ++  3 42 ++  4 41 ++  5 30 +  6 45 ++  7 (comparative) 20 −  8 (comparative) 56 ++  9 (comparative) 52 ++ 10 (comparative) 50 ++

[0104] Application Tests

[0105] The polymers were tested as dispersants in cement and CaSO.sub.4 anhydride.

[0106] Calcium Sulfate Anhydride:

[0107] 394 g synthetic anhydride

[0108] 600 g standard sand

[0109] 140 g water

[0110] 3.94 g K.sub.2SO.sub.4

[0111] Dispersant from experiments 1 to 12

[0112] Mixing procedure as per EN 196 Part I with Hägermann ring

TABLE-US-00003 TABLE 3 Slump [cm] Solidifica- 30 60 90 tion [h] Dispersant Metering 0 min 5 min min min min BS ES 1 0.09 27 26 23.5 23 22.5 8.5 10.4 2 0.08 26.5 25.5 23.5 22.5 22 7.9 9.7 3 0.09 27 26 23.5 23 22.5 7.7 10.4 4 0.08 26.5 25.5 23.5 22.5 22 8.0 10.5 5 0.09 27 26 24 24 23.5 8.5 10.4 6 0.08 27 25 23 22.5 22.5 8.9 10.1 7 0.09 27 26 23.5 23 22.5 15.3 20.1 8 0.07 27 23.5 22 19.5 18 7.6 9.5 9 0.07 28 26 24 23 22 8.0 9.9 10 0.08 27 26 24 23 22 7.9 10.0 11 0.12 28 23 22.5 22 21.5 8.1 10.0 12 0.12 27 26.5 24.5 23 22 7.3 9.6 The metering relates to the synthetic anhydride and is stated in wt % BS: beginning of solidification ES: end of solidification The solidification times were determined in analogy to DIN-EN 480-2.

[0113] Segregation Tendency in Anhydrite Mortar

[0114] The robustness is also reflected in the stability toward bleeding. In this case a cylindrical cone was used with a height of 450 mm and a width of 50 mm. The mortar employed was the following formulation:

[0115] 394 g synthetic anhydride

[0116] 600 g standard sand

[0117] 140 g water

[0118] 4 g potassium sulfate

[0119] Dispersants from experiments 5 to 12 in analogy to the metering from table 3

[0120] The mixture was stirred for 30 seconds following addition of water. 450 ml of this mortar were introduced into the cone, and after 10 minutes the bleed water was drawn off and the volume was ascertained.

TABLE-US-00004 TABLE 4 Dispersant Bleed water [ml] 5 3 6 6.1 7 2 8 25 9 26 10 25 11 24 12 56

[0121] A Further Round of Measurement Was Carried Out With the Following Mixture:

[0122] 900 g synthesis anhydride

[0123] 1350 g standard sand

[0124] 9 g potassium sulfate

[0125] The water/binder ratio was w/b=0.35

TABLE-US-00005 TABLE 5 Bleeding Solidification after Slump [cm] [h:min] 30 min Dispersant Metering 0 min 5 min 30 min 60 min 90 min BS ES [g] 7 0.07 28 25.5 25.4 23 22.3 15:04 22:22 0 9 0.07 28.4 26.1 24.8 23.6 22.6 16:20 20:00 0.06 3 0.08 28.5 26.7 25.5 24.2 23.5 13:06 19:20 0.03

[0126] The metering relates to the synthesis anhydride and is stated in wt %.

[0127] BS: beginning of solidification

[0128] ES: end of solidification

[0129] The amount of bleed water was determined in a 210 ml volumetric cylinder having a diameter of 4 cm and a filling height of 18 cm

[0130] Testing of Different Plasticizers in Cement Mortar:

[0131] Cement/silica sand 1/1

[0132] w/c=0.35

[0133] Dispersants from experiments 1 to 7

[0134] The slump was adjusted to an initial slump in the Hägermann ring without tapping of 13 +/−0.5 cm. The Marsh funnel indicates the flow transit time of the mortar mixture at comparable slump (ASTM C939-10).

TABLE-US-00006 TABLE 6 Flow transit Slump [cm] time Dispersant Metering 0 min 5 min 30 min 60 min [s] 1 0.20 13.3 10.4 8.5 7.3 90 3 0.220 13.8 10.5 7.9 6.9 90 7 0.225 13.1 10.3 8.0 7.6 104 8 0.20 13.8 13.9 14.9 16.0 155

[0135] The metering relates to the cement and is stated in wt %

[0136] To evaluate the metering robustness, different w/c ratios (0.38; 0.40; 0.42) were set for the same metering (FIG. 1).

[0137] Only the dispersants of the invention exhibited good powder quality at the same time as good performance properties.