Copolymers suitable for plasticizing inorganic binder systems

Abstract

Copolymers that comprise salicylic acid derivative structural units and structural units having free polyether side chains. The copolymers are suitable to plasticize inorganic binder systems, construction chemical compositions comprising the copolymers and the use of the copolymers as a plasticizer for inorganic binder systems. Binder systems with a reduced amount of Portland cement comprising at least one copolymer of the invention provide a better liquefaction and processability as compared to the binder systems without a copolymer of the invention.

Claims

1. A copolymer comprising structural units of formula (I) ##STR00019## wherein R.sup.30, R.sup.31 and R.sup.32 independently of each other represent a hydrogen atom, an alkyl group with 1 to 6 carbon atoms or COOM; X is NH, N(C.sub.1-C.sub.4 alkyl) or O; R.sup.33 is OH, NR.sup.34R.sup.35, COOM, COOR.sup.34, SO.sub.3M, SO.sub.3R.sup.34, NO.sub.2, C.sub.1-C.sub.6 alkoxy or C.sub.1-C.sub.6 alkyl; R.sup.34 and R.sup.35 independently of each other represent H, C.sub.1-C.sub.6 alkyl, phenyl, C.sub.1-C.sub.6 alkyl- phenyl or phenyl-C.sub.1-C.sub.6 alkyl; t is 0, 1, 2, or 3; x is 0 or 1; n is 1, 2 or 3; y is 0 or 1; z is 0 or 1; and M is H or a cation equivalent; and structural units having free polyether side chains, wherein the structural units having free polyether side chains are selected from units of the formulae (IIa), (IIb), (IIc) and/or (IId): (IIa): ##STR00020## wherein R.sup.10, R.sup.11 and R.sup.12 independently of one another are H or an unbranched or branched C.sub.1-C.sub.4 alkyl group; Z is O or S; E is an unbranched or branched C.sub.1-C.sub.6 alkylene group, a cyclohexylene group, CH.sub.2C.sub.6H.sub.10 (CH.sub.2-cyclohexyl-), 1,2-phenylene, 1,3-phenylene or 1,4-phenylene; G is O, NH or CONH; or E and G together are a chemical bond; A is C.sub.xH.sub.2x with x=2, 3, 4 or 5, or is CH.sub.2CH(C.sub.6H.sub.5); n is 0, 1, 2, 3, 4 or 5; a is an integer from 2 to 350; R.sup.13 is H, an unbranched or branched C.sub.1-C.sub.4 alkyl group, CONH.sub.2 and/or COCH.sub.3; (IIb): ##STR00021## in which R.sup.16, R.sup.17 and R.sup.18 independently of one another are H or an unbranched or branched C.sub.1-C.sub.4 alkyl group; E is an unbranched or branched C.sub.1-C.sub.6 alkylene group, a cyclohexylene group, CH.sub.2C.sub.6H.sub.10 (CH.sub.2-cyclohexyl-), 1,2-phenylene, 1,3-phenylene, or 1,4-phenylene, or is a chemical bond; A is C.sub.xH.sub.2x with x=2, 3, 4 or 5, or is CH.sub.2CH(C.sub.6H.sub.5); n is 0, 1, 2, 3, 4 and/or 5; L is C.sub.xH.sub.2x with x=2, 3, 4 or 5, or is CH.sub.2CH(C.sub.6H.sub.5); a is an integer from 2 to 350; d is an integer from 1 to 350; R.sup.19 is H or an unbranched or branched C.sub.1-C.sub.4 alkyl group; R.sup.20 is H or an unbranched C.sub.1-C.sub.4 alkyl group; (IIc): ##STR00022## in which R.sup.21, R.sup.22 and R.sup.23 independently of one another are H or an unbranched or branched C.sub.1-C.sub.4 alkyl group or COOM; W is O, NR.sup.25, or is N; V is 1 if W=O or NR.sup.25, and is 2 if W=N; A is C.sub.xH.sub.2x with x=2, 3, 4 or 5, or is CH.sub.2CH(C.sub.6H.sub.5); a is an integer from 2 to 350; R.sup.24 is H or an unbranched or branched C.sub.1-C.sub.4 alkyl group; and R.sup.25 is H or an unbranched or branched C.sub.1-C.sub.4 alkyl group; (IId): ##STR00023## in which R.sup.6 is H or an unbranched or branched C.sub.1-C.sub.4 alkyl group, Q is NR.sup.10, N or O, V is 1 if Q=O or NR.sup.10 and is 2 if Q=N; R.sup.10 is H or an unbranched or branched C.sub.1-C.sub.4 alkyl group; and A is C.sub.xH.sub.2x with x=2, 3, 4 or 5, or is CH.sub.2CH(C.sub.6H.sub.5); R.sup.24 is H or an unbranched or branched C.sub.1-C.sub.4 alkyl group; M is H or a cation equivalent; and a is an integer from 2 to 350.

2. The copolymer according to claim 1, wherein t is 0.

3. The copolymer according to claim 2, comprising structural units of formula (Ib) ##STR00024##

4. The copolymer according to claim 1, wherein R.sup.30 is H or CH.sub.3, R.sup.31 is H, R.sup.32 is H or COOM, x is 0, y is 1, and z is 1.

5. The copolymer according to claim 1, wherein R.sup.30 is H or CH.sub.3, R.sup.31 and R.sup.32 are H, x is 0, 1 or 2, y is 0 and z is 1.

6. The copolymer according to claim 1, wherein the copolymer comprises: structural units (IIa), wherein: a) Z is O and E and G together are a chemical bond, R.sup.10 and R.sup.12 are H, R.sup.11 is H or CH.sub.3, n is 1 or 2 and R.sup.13 is H or an unbranched or branched C.sub.1-C.sub.4 alkyl group; or b) Z is O, E is an unbranched or branched C.sub.1-C.sub.6 alkylene group, G is O, R.sup.10, R.sup.11 and R.sup.12 are H, n is 0 and R.sup.13 is H or an unbranched or branched C.sub.1-C.sub.4 alkyl group; or structural units (IIc), wherein W is O or NR.sup.25.

7. The copolymer according to claim 6, wherein in structural units (IIc) R.sup.21 and R.sup.23 are H, R.sup.22 is H or CH.sub.3 and R.sup.24 is H or an unbranched or branched C.sub.1-C.sub.4 alkyl group.

8. The copolymer according to claim 1, wherein the copolymer comprises structural units (IId), wherein R.sup.6 is H, Q is O, and R.sup.24 is H or an unbranched or branched C.sub.1-C.sub.4 alkyl group.

9. The copolymer according to claim 1, wherein a in formulae (IIa), (IIb), (IIc) and/or (IId) is 5 to 135.

10. The copolymer according to claim 1, additionally comprising structural units of the general formulae (IIIa), (IIIb), (IIIc) and/or (IIId): ##STR00025## in which R.sup.1 is H or an unbranched or branched C.sub.1-C.sub.4 alkyl group, CH.sub.2COOH or CH.sub.2COXR.sup.2; X is NH(C.sub.nH.sub.2n), O(C.sub.nH.sub.2n) with n=1, 2, 3 or 4, where the nitrogen atom or the oxygen atom is bonded to the CO group, or is a chemical bond; R.sup.2 is OM, PO.sub.3M.sub.2, or OPO.sub.3M.sub.2, with the proviso that X is a chemical bond if R.sup.2 is OM; (IIIb): ##STR00026## in which R.sup.3 is H or an unbranched or branched C.sub.1-C.sub.4 alkyl group; n is 0, 1, 2, 3 or 4; R.sup.4 is PO.sub.3M.sub.2, or OPO.sub.3M.sub.2; (IIIc): ##STR00027## in which R.sup.5 is H or an unbranched or branched C.sub.1-C.sub.4 alkyl group; Z is O or NR.sup.7; R.sup.7 is H, (C.sub.nH.sub.2n)OH, (C.sub.nH.sub.2n)PO.sub.3M.sub.2, (C.sub.nH.sub.2n)OPO.sub.3M.sub.2, (C.sub.6H.sub.4)PO.sub.3M.sub.2, or (C.sub.6H.sub.4)OPO.sub.3M.sub.2, and n is 1, 2, 3 or 4; (IIId): ##STR00028## in which R.sup.6 is H or an unbranched or branched C.sub.1-C.sub.4 alkyl group; Q is NR.sup.7 or O; R.sup.7 is H, (C.sub.nH.sub.2n)OH, (C.sub.nH.sub.2n)PO.sub.3M.sub.2, (C.sub.nH.sub.2n)OPO.sub.3M.sub.2, (C.sub.6H.sub.4)PO.sub.3M.sub.2, or (C.sub.6H.sub.4)OPO.sub.3M.sub.2, n is 1, 2, 3 or 4; and each M in the formulae (IIIa) to (IIId) independently of one another is H or a cation equivalent.

11. A construction chemical composition comprising at least one copolymer according to claim 1 and an inorganic binder.

12. The composition of claim 11, wherein the inorganic binder is selected from hydraulic binders, latent hydraulic binders, puzzolanic binders, alkali-activated and alkali-activatable aluminosilicate binders, and mixtures thereof.

13. The composition of claim 12, wherein: the hydraulic binders are selected from cements, the latent hydraulic binders are selected from industrial slags, synthetic slags, and mixtures thereof, the puzzolanic binders are selected from amorphous silica, pyrogenic silica, microsilica, glass powder, fly ash, and mixtures thereof.

14. A method of using the copolymer according to claim 1 as a dispersant for inorganic binders, the method comprising mixing the copolymer according to claim 1 with an inorganic binder.

15. The copolymer according to claim 2, comprising structural units of formula (Ic) ##STR00029##

16. The composition of claim 13, wherein the cements are selected from Portland cements, aluminate cements and mixtures thereof.

17. The composition of claim 13, wherein the industrial or synthetic slags are selected from blast furnace slag, granulated blast furnace slag, ground granulated blast furnace slag, electrothermical phosphorus slag, stainless steel slag, and mixtures thereof.

18. The composition of claim 13, wherein the puzzolanic binders are selected from brown coal fly ash and mineral coal fly ash, metakaolin, natural puzzolans such as tuff, trass, volcanic ash, natural and synthetic zeoliths and mixtures thereof.

Description

EXAMPLE 1 (E1)

(1) Reaction of 4-Aminosalicylic Acid with Maleic Anhydride to Salicylic Acid-4-Maleimide

(2) ##STR00017##

(3) A reaction vessel with a stirrer and a pH-electrode was charged with 306 g (2 mol) 4-aminosalicylic acid and 1350 g of water to obtain a suspension. NaOH was added in order to adjust the pH-value to 6.5 resulting in a brownish solution.

(4) In a separate vessel 235 g (2.4 mol) maleic anhydride was dissolved in 450 ml acetone. Said solution was added dropwise to the reaction vessel over a time period of three hours. Simultaneously the pH-value of the reaction solution was kept in a range of 5.5-6.5 by continuous addition of a 50% NaOH-solution. After the addition of the maleic anhydride solution was completed, the resulting mixture was stirred at room temperature for two hours. Then the solution was stored in a refrigerator to crystallize salicylic acid-4-maleimide. After filtration 400 g of salicylic acid-4-maleimide were obtained.

EXAMPLE 2 (E2)

(5) Reaction of 4-Aminosalicylic Acid with Methacrylic Acid Anhydride to Salicylic Acid-4-Methacrylic Amide

(6) ##STR00018##

(7) In a reaction vessel with a stirrer, a dropping funnel and a drying tube 153 g (1 mol) of 4-aminosalicylic acid were dissolved in 1228 g of anhydrous acetone. To this solution 164 g (1 mol) methacrylic acid anhydride were added dropwise over a time period of one hour. After complete addition the resulting mixture was stirred for 20 min at room temperature. Then 101 g (1 mol) triethylamine were added via the dropping funnel over a time period of 1 hour. After complete addition the resulting mixture was stirred for three hours at room temperature. 900 mL of acetone were removed under reduced pressure and the resulting residue was diluted with water (200 mL). The obtained solution showed a pH-value of about 5. By adding sulfuric acid (25%) the pH-value was adjusted to 2-3, resulting in the precipitation of fine white precipitate. After filtration and washing with cold water 210 g of salicylic acid-4-methacrylic amide were obtained.

EXAMPLE 3 (E3)

(8) A double-jacketed reaction vessel with a stirrer, a thermometer and a pH-electrode was charged at room temperature with a solution of 75 g vinyloxybutyl-polyethyleneglycol (V-PEG, molecular weight=500 g/mol) and 60 ml of water. The reaction vessel was additionally charged with 900 mg of 3-mercaptopropionic acid.

(9) In a separate vessel 48 g of salicylic acid-4-maleimide (Example 1) were dissolved in water (150 mL) under addition of 20% NaOH (13 mL). Said solution was added to the reaction vessel under vigorous stirring and cooling. The temperature was kept below 15 C.; the pH-value was kept in a range of 4.8 to 5.2 (if necessary, the pH-value may be adjusted by adding 20% sulfuric acid or NaOH-solution).

(10) Then 45 mg iron-(II)-sulfate and 2.8 g of a 30% hydrogen peroxide solution were added. Further, a solution of Rongalit (sodium hydroxymethylsulfinate, product of BASF SE, 2.5 g) in water (47.5 mL), which was also prepared in a separate vessel, was pumped into the reaction vessel (dosing rate=4.6 mL/h). After complete addition of the Rongalit-solution the polymerization was complete. In the case peroxide may still be detectable in the solution, it can be decomposed by further addition of Rongalit.

(11) The obtained polymer solution was neutralized to pH 7. The resulting polymer had an average molecular weight Mw of 22280 g/mol.

EXAMPLE 4 (E4)

(12) A double-jacketed reaction vessel with a stirrer, a thermometer and a pH-electrode was charged with a solution of 150 g vinyloxybutyl-polyethyleneglycol (V-PEG, molecular weight=1100 g/mol) and 120 ml of water at room temperature. The reaction vessel was additionally charged with 2.1 mg of 3-mercaptopropionic acid.

(13) In a separate vessel 59 g of salicylic acid-4-maleimide (Example 1) were dissolved in water (180 mL) under addition of 20% NaOH (13 mL). Said solution was added to the reaction vessel under vigorous stirring and cooling. The temperature was kept below 15 C.; the pH-value was kept in a range of 4.8 to 5.2. (if necessary, the pH-value may be adjusted by adding 20% sulfuric acid or NaOH-solution).

(14) Then 62 mg iron-(II)-sulfate and 3.8 g of a 30% hydrogen peroxide solution were added. Further, a solution of Rongalit (sodium hydroxymethylsulfinate, product of BASF SE, 2.5 g) in water (47.5 mL), which was also prepared in a separate vessel, was pumped into the reaction vessel (dosing rate=14.3 mL/h). After complete addition of the Rongalit-solution the polymerization was complete. In the case peroxide may still be detectable in the solution, it can be decomposed by further addition of Rongalit.

(15) The obtained polymer solution was neutralized to pH 7. The resulting polymer had an average molecular weight Mw of 22500 g/mol.

EXAMPLE 5 (E5)

(16) A double-jacketed reaction vessel with a stirrer, a thermometer and a pH-electrode was charged with a solution of 28.5 g of -methylpolyethyleneglycol methacrylic acid ester (M PEG-MA, molecular weight=950 g/mol) and water (28.5 ml) at room temperature. The reaction vessel was additionally charged with 0.24 g 2-mercaptoethanol.

(17) In a separate vessel 36 g of sodium carbonate and 20 g of salicylic acid-4-methacrylicamide (Example 2) were dissolved in water (144 g) (solution 1). In another separate vessel 484 mg of azo initiator V044 (2,2-Azobis[2-(2-imidazolin-2-yl)propane]dihydrochloride) were dissolved in 27 g of water (solution 2).

(18) Under stirring and purging with nitrogen the mixture in the reaction vessel was heated to 90 C. When 90 C. were reached, solution 1 (dosing rate=66.7 ml/h) and solution 2 (dosing rate=7.5 ml/h) were simultaneously added. After complete addition of solutions 1 and 2, the resulting mixture was stirred for one hour at 90 C.

(19) The resulting polymer solution was neutralized to pH 8. The polymer had an average molecular weight Mw of 24300 g/mol.

EXAMPLE 6 (E6)

(20) A double-jacketed reaction vessel with a stirrer, a thermometer and a pH-electrode was charged with a solution of 68.4 g of w-methylpolyethyleneglycol methacrylic acid ester (M PEG-MA, molecular weight=950 g/mol) and water (75 ml) at room temperature. The reaction vessel was additionally charged with 0.67 g 2-mercaptoethanol.

(21) In a separate vessel 48 g of sodium carbonate, 26.5 g of salicylic acid-4-methacrylicamide (Example 2) and 17 g methacrylic acid were dissolved in water (190 g) (solution 1). In another separate vessel 1.36 g of azo initiator V044 (2,2-Azobis[2-(2-imidazolin-2-yl)propane]dihydrochloride) were dissolved in 36 g of water (solution 2).

(22) Under stirring and purging with nitrogen the mixture in the reaction vessel was heated to 90 C. When 90 C. were reached, solution 1 (dosing rate=94 ml/h) and solution 2 (dosing rate=12 ml/h) were simultaneously added. After complete addition of solutions 1 and 2, the resulting mixture was stirred for one hour at 90 C.

(23) The resulting polymer solution was neutralized to pH 8. The polymer had an average molecular weight Mw of 22200 g/mol.

EXAMPLE 7 (E7)

(24) A double-jacketed reaction vessel with a stirrer, a thermometer and a pH-electrode was charged with a solution of 68.4 g of w-methylpolyethyleneglycol methacrylic acid ester (M PEG-MA, molecular weight=950 g/mol) and water (75 ml) at room temperature. The reaction vessel was additionally charged with 0.65 g 2-mercaptoethanol.

(25) In a separate vessel 48 g of sodium carbonate, 26.5 g of salicylic acid-4-methacrylicamide (Example 2) and 35 g hydroethylmethacrylate phosphoric acid ester were dissolved in water (190 g) (solution 1). In another separate vessel 1.36 g of azo initiator V044 (2,2-Azobis[2-(2-imidazolin-2-yl)propane]dihydrochloride) were dissolved in 36 g of water (solution 2).

(26) Under stirring and purging with nitrogen the mixture in the reaction vessel was heated to 90 C. When 90 C. were reached, solution 1 (dosing rate=100 ml/h) and solution 2 (dosing rate=12 ml/h) were simultaneously added. After complete addition of solutions 1 and 2, the resulting mixture was stirred for one hour at 90 C.

(27) The resulting polymer solution was neutralized to pH 8. The polymer had an average molecular weight Mw of 21500 g/mol.

COMPARATIVE EXAMPLE 1 (C1)

(28) A double-jacketed reaction vessel with a stirrer, a thermometer and a pH-electrode was charged with a solution of 68.4 g of w-methylpolyethyleneglycol methacrylic acid ester (M PEG-MA, molecular weight=950 g/mol) and water (75 ml) at room temperature. The reaction vessel was additionally charged with 0.65 g 2-mercaptoethanol.

(29) In a separate vessel 20.3 g methacrylic acid were dissolved in water (20 g) (solution 1). In another separate vessel 0.55 g of azo initiator V044 (2,2-Azobis[2-(2-imidazolin-2-yl)propane]dihydrochloride) were dissolved in 20 g of water (solution 2).

(30) Under stirring and purging with nitrogen the mixture in the reaction vessel was heated to 90 C. When 90 C. were reached, solution 1 (dosing rate=10 ml/h) and solution 2 (dosing rate=6.7 ml/h) were simultaneously added. After complete addition of solutions 1 and 2, the resulting mixture was stirred for one hour at 90 C.

(31) The resulting polymer solution was neutralized to pH 8. The polymer had an average molecular weight Mw of 26300 g/mol.

(32) Application Tests

(33) In the following tests the mortar plasticization (spread) of geopolymer binder systems containing copolymers of the invention and comparative systems was tested. Aluminosilicate mortars were produced using a mortar mixer according to DIN EN 196-1. All ingredients were mixed according DIN EN 196-1, except that the quartz sand was added before mixing, instead of adding it at the end of the mixing process. The mortar spread was measured by means of a Haegermann cone after 15 times knocking on a spread table (DIN EN 1015-3). Blast furnace slag as contained in the binder systems was composed as follows (amounts given in wt. %):

(34) TABLE-US-00001 CaO SiO.sub.2 Al.sub.2O.sub.3 MgO Fe.sub.2O.sub.3 TiO.sub.2 K.sub.2O Rest Slag 42.8 34.7 11.4 5.3 0.7 1.2 0.6 3.3

(35) All tested copolymers were formulated with 4 wt.-% defoamer Dowfax DF 141 (nonionic defoamer comprising a copolymer of ethylene oxide, propylene oxide and/or butylene oxide), relative to the polymer. The polymer dosage was 1 wt.-%, relative to the geopolymer binder.

(36) Application Test 1

(37) The following geopolymer binder system was prepared:

(38) TABLE-US-00002 Slag 300 g Quartz sand 700 g KOH 12 g Na.sub.2CO.sub.3 12 g Copolymer 3 g

(39) The water/slag ratio was 0.53. The spread values are given in Table 1. Spreads after 6 min and 30 min are given in cm. The sample numbers refer to the Examples above.

(40) TABLE-US-00003 TABLE 1 No copolymer Sample added E3 E4 E5 E6 E7 C1 Spread after 15.7 20.3 16.7 19.2 18.7 19.0 15.9 6 min Spread after 15.4 19.6 16.1 18.5 18.5 19.0 15.2 30 min
Application Test 2

(41) The following geopolymer binder system was prepared:

(42) TABLE-US-00004 Slag 300 g Quartz sand 700 g Na.sub.2CO.sub.3 6 g Copolymer 3 g

(43) The water/slag ratio was 0.583. The spread values are given in Table 2. Spreads after 6 min and 30 min are given in cm. The sample numbers refer to the Examples above.

(44) TABLE-US-00005 TABLE 2 No copolymer Sample added E3 E4 E5 E6 E7 C1 Spread after 14.0 15.4 16.4 16.6 17.5 17.7 14.3 6 min Spread after 13.7 15.4 16.1 16.4 17.6 18.0 14.1 30 min
Application Test 3

(45) The following geopolymer binder system was prepared:

(46) TABLE-US-00006 Slag 300 g Quartz sand 700 g Na.sub.2SiO.sub.3 6 g Copolymer 3 g

(47) The water/slag ratio was 0.583. The spread values are given in Table 3 herein below (two parts). Spreads after 6 min and 30 min are given in cm. The sample numbers refer to the Examples above.

(48) TABLE-US-00007 TABLE 3 No copolymer Sample added E3 E4 E5 E6 E7 C1 Spread after 14.5 15.9 16.6 15.9 16.4 16.8 14.5 6 min Spread after 14.2 15.5 15.9 15.0 16.6 17.0 14.3 30 min

(49) Application tests 1 to 3 show that Samples E3 to E7 show a better spread (this corresponds to a better plasticization) of the used binder systems as compared to samples without a copolymer of the invention or samples containing a copolymer without salicylic acid moieties. The addition of additives such as Na.sub.2CO.sub.3, KOH or Na.sub.2SiO.sub.3 seems not to have a significant influence on the spread.