Additive for masses that set hydraulically

Abstract

The invention relates to an additive which can be used as a hardening accelerator for hydraulically setting compositions, comprising a) at least one polymeric dispersant comprising structural units having anionic or anionogenic groups and structural units having polyether side chains, b) at least one sulfonic acid compound of the formula (I) ##STR00001##
in which A.sup.1 is NH.sub.2, NHMe, NMe.sub.2, N(CH.sub.2—CH.sub.2—OH).sub.2, CH.sub.3, C.sub.2H.sub.5, CH.sub.2—CH.sub.2—OH, phenyl, or p-CH.sub.3-phenyl and K.sup.n+ is an alkali metal cation, or one equivalent of a cation selected from Ca.sup.2+, Mg.sup.2+, Sr.sup.2+, Ba.sup.2+, Zn.sup.2+, Fe.sup.2+, Fe.sup.3+, Al.sup.3+, Mn.sup.2+, or Cu.sup.2+, and c) calcium silicate hydrate particles.

Claims

1. An additive for hydraulically setting compositions, comprising a) at least one polymeric dispersant comprising structural units having anionic or anionogenic groups and structural units having polyether side chains, b) at least one sulfonic acid compound of the formula (I) ##STR00028## in which A.sup.1 is NH.sub.2, NHMe, NMe.sub.2, N(CH.sub.2—CH.sub.2—OH).sub.2, CH.sub.3, C.sub.2H.sub.5, CH.sub.2—CH.sub.2—OH, phenyl, or p-CH.sub.3-phenyl, and K.sup.n+ is an alkali metal cation, or a cation selected from Ca.sup.2+, Mg.sup.2+, Sr.sup.2+, Ba.sup.2+, Zn.sup.2+, Fe.sup.2+, Fe.sup.3+, Al.sup.3+, Mn.sup.2+, or Cu.sup.2+, and n is the value of the cation; and c) calcium silicate hydrate particles.

2. The additive as claimed in claim 1, wherein A.sup.1 is NH.sub.2 or CH.sub.3.

3. The additive as claimed in claim 1, wherein K.sup.n+ is Na.sup.+, K.sup.+, or Ca.sup.2+.

4. The additive as claimed in claim 1, prepared by reacting a calcium salt of at least one sulfonic acid compound of the formula (I) with at least one water-soluble inorganic silicate compound in the presence of an aqueous solution of the dispersant.

5. The additive as claimed in claim 1, in the form of a suspension or in solid form, more particularly as powder.

6. The additive as claimed in claim 1, having in powder form a water content of less than 10 wt %.

7. The additive as claimed in claim 1, wherein the molar ratio of calcium to silicon in the calcium silicate hydrate particles is 0.6 to 2.

8. The additive as claimed in claim 1, wherein the dispersant comprises at least one polymer obtained by polymerizing at least one monomer having at least one anionic or anion genic group and at least one monomer comprising at least one polyether side chain.

9. The additive as claimed in claim 8, wherein the polymer as polyether side chain has at least one structural unit of the general formulae (IIa), (IIb), (IIc) and/or (IId): ##STR00029## 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 alkaline group, a cyclohexene group, CH.sub.2—C.sub.6H.sub.10, 1,2-phenylene, 1,3-phenylene, or 1,4-phenylene; G is O, NH, or CO—NH; or E and G together are a chemical bond; A is C.sub.xH.sub.2x wherein x is 2, 3, 4, or 5, or CH.sub.2CH(C.sub.6H.sub.5); n is 0, 1, 2, 3, 4, and/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, CO—NH.sub.2 and/or COCH.sub.3; ##STR00030## wherein 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.2—C.sub.6H.sub.10, 1,2-phenylene, 1,3-phenylene, or 1,4-phenylene, or a chemical bond; A is C.sub.xH.sub.2x wherein x is 2, 3, 4, or 5, or CH.sub.2CH(C.sub.6H.sub.5); L is C.sub.xH.sub.2x wherein x is 2, 3, 4, or 5, or CH.sub.2—CH(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 or branched C.sub.1-C.sub.4 alkyl group; and n is 0, 1, 2, 3, 4, or 5; ##STR00031## 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; W is O, NR.sup.25, or N; Y is 1 if W═O or NR.sup.25, and is 2 if W═N; A is C.sub.xH.sub.2x wherein x is 2, 3, 4, or 5, or 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; R.sup.25 is H or an unbranched or branched C.sub.1-C.sub.4 alkyl group; ##STR00032## 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; Y 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; A is C.sub.xH.sub.2x wherein x is 2, 3, 4, or 5, or CH.sub.2C(C.sub.6H.sub.5)H; R.sup.24 is H or an unbranched or branched C.sub.1-C.sub.4 alkyl group; M is H or one cation equivalent; and a is an integer from 2 to 350.

10. The additive as claimed in claim 8, wherein the polymer as anionic or anionogenic group has at least one structural unit of the formulae (Ia), (Ib), (Ic) and/or (Id): ##STR00033## wherein R.sup.1 is H or an unbranched or branched C.sub.1-C.sub.4 alkyl group, CH.sub.2COOH, or CH.sub.2CO—X—R.sup.3; X is NH—(C.sub.nH.sub.2n) or O—(C.sub.nH.sub.2n), wherein n is 1, 2, 3, or 4, or is a chemical bond, the nitrogen atom or oxygen atom, respectively, being bonded to the CO group; R.sup.2 is OM, PO.sub.3M.sub.2, or O—PO.sub.3M.sub.2; with the proviso that X is a chemical bond if R.sup.2 is OM; R.sup.3 is PO.sub.3M.sub.2, or O—PO.sub.3M.sub.2; ##STR00034## wherein 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 O—PO.sub.3M.sub.2; ##STR00035## wherein 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; and 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; ##STR00036## wherein 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 independently of any other is H or one cation equivalent.

11. The additive as claimed in claim 10, wherein the dispersant comprises no units of the formula (IIc) when it comprises units of the formula (Ia) in which X is a chemical bond and R.sup.2 is M.

12. The additive as claimed in claim 10, wherein the dispersant comprises at least one polymer which is a polycondensation product comprising structural units (III) and (IV): ##STR00037## wherein T is a substituted or unsubstituted phenyl radical, a substituted or unsubstituted naphthyl radical or a substituted or unsubstituted heteroaromatic radical having 5 to 10 ring atoms, of which 1 or 2 atoms are heteroatoms selected from N, O, and S; n is 1 or 2; B is N, NH, or O, with the proviso that n is 2 if B is N and with the proviso that n is 1 if B is NH or O; A is C.sub.xH.sub.2x wherein x is 2, 3, 4, or 5, or CH.sub.2CH(C.sub.6H.sub.5); a is an integer from 1 to 300; R.sup.25 is H, a branched or unbranched C.sub.1 to C.sub.10 alkyl radical, C.sub.5 to C.sub.8 cycloalkyl radical, aryl radical, or heteroaryl radical having 5 to 10 ring atoms, of which 1 or 2 atoms are heteroatoms selected from N, O, and S; the structural unit (IV) being selected from the structural units (IVa) and (IVb): ##STR00038## wherein D is a substituted or unsubstituted phenyl radical, a substituted or unsubstituted naphthyl radical or a substituted or unsubstituted heteroaromatic radical having 5 to 10 ring atoms, of which 1 or 2 atoms are heteroatoms selected from N, O, and S; E is N, NH, or O, with the proviso that m is 2 if E is N and with the proviso that m is 1 if E is NH or O; A is C.sub.xH.sub.2x wherein x is 2, 3, 4, or 5, or CH.sub.2CH(C.sub.6H.sub.5); b is an integer from 1 to 300; M independently at each occurrence is H or one cation equivalent; ##STR00039## in which V is a substituted or unsubstituted phenyl radical or a substituted or unsubstituted naphthyl radical; R.sup.7 is COOM, OCH.sub.2COOM, SO.sub.3M, or OPO.sub.3M.sub.2; M is H or one cation equivalent; the phenyl, naphthyl or heteroaromatic radicals mentioned being optionally substituted by 1 or two radicals selected from R.sup.8, OH, OR.sup.8, (CO)R.sup.8, COOM, COOR.sup.8, SO.sub.3R.sup.8, and NO.sub.2; and and R.sup.8 is C.sub.1-C.sub.4 alkyl, phenyl, naphthyl, phenyl-C.sub.1-C.sub.4 alkyl, or C.sub.1-C.sub.4 alkylphenyl.

13. A process for preparing an additive as claimed in claim 1, comprising the steps of: reacting at least one sulfonic acid compound of the formula (I) in which K.sup.n+ is Ca.sup.2+ with at least one water-soluble inorganic silicate compound in the presence of an aqueous solution of a dispersant.

14. The process as claimed in claim 13, comprising an additional process step of drying the hardening accelerator composition, the drying taking place preferably by spray drying or roll drying.

15. A building material mixture comprising a hydraulic binder and the additive as claimed in claim 1.

16. A building material mixture comprising a hydraulic binder and the additive as claimed in claim 2.

17. A building material mixture comprising the additive as claimed in claim 1 and at least one member selected from the group consisting of Portland cement, slag, flyash, lime and a pozzolan.

18. A method for preparing a building material mixture comprising mixing the additive as claimed in claim 1 with a hydraulic binder.

Description

EXAMPLE 1

(1) Preparation of the Hardening Accelerator Suspension H1 (Not Inventive)

(2) A calcium source was prepared by weighing out 600 g of Ca(OH).sub.2 (purity 92%) and 488 g of Ca(CH.sub.3COO.sup.−).sub.2 (purity 100%) into 4.328 kg of H.sub.2O. A silicate source was prepared by weighing out 2.28 kg of sodium waterglass (solids content=36.1 wt %) with an SiO.sub.2/Na.sub.2O molar ratio of 3.4 into 1.15 kg of H.sub.2O. A dispersant solution was prepared by weighing out 2.268 kg of polymer 3 (35 wt % strength polymer solution) and 0.523 kg of polymer 2 (35 wt % strength polymer solution) into 8.36 kg of H.sub.2O. The dispersant solution was introduced initially and was pumped in circulation through a high-energy mixer equipped with rotor/stator system. In the high-energy mixer, the calcium source, which is stirred to prevent sedimentation, and the silicate source are metered completely into the initially introduced solution over the course of 80 minutes, with the rotor/stator system at a rotational speed of 8000 rpm. During this procedure, the initial charge introduced is maintained at 20° C.

(3) The solids content of H1 is 14.7 wt %, as determined by drying to constant weight in a forced-air drying cabinet at 60° C.

(4) Influence of the Hardening Accelerator Suspensions on Hardening (Not Inventive)

(5) The effect of the hardening accelerator suspensions H1 on hardening was tested on the cement (CEM I Milke 52.5 R) by measurement of the release of heat, using heat flow calorimetry (figure 1). The hardening accelerator suspension was mixed with the batching water, and the resulting suspension was mixed with 20 g of the cement. The water-to-cement ratio (w/c) was set at 0.32. The level at which the accelerator under test was added was 0.6 wt % of solids content of H1, based on the cement weight. The heat flow curves are shown in figure 1. The addition of the hardening accelerator suspension accelerates the hardening (defined in H. F. W. Taylor (1997): Cement Chemistry, 2nd edition, p. 212ff). The effect is summarized in table 1.

(6) The reference represents the heat flow of CEM I Milke 52.5 R without addition of an accelerator; curve 2 shows the heat flow for CEM I Milke 52.5 R are with addition of 0.6 wt % of the hardening accelerator suspension H1.

(7) TABLE-US-00002 TABLE 1 Heat flow in the main hydration period Cumulative heat of hydration Acceleration after 6 h relative to Sample (J/g) reference (%) CEM I Milke 52.5 R without accelerator 40.7 — with 0.6 wt % of suspension H1 96.0 236

EXAMPLE 2

(8) Production of Dried Hardening Accelerators

(9) Hardening accelerator suspension H1 was admixed with drying assistants and dried. Drying took place by spray drying, with the drying assistant having been mixed with the hardening accelerator suspension H1 prior to the drying operation for around 5 minutes. The amounts of the hardening accelerator suspension H1 weighed out for the spray drying, and the amounts of the respective drying assistants used, are shown in table 2. For the comparative examples TH1-e to TH1-h, calcium chloride is used as the drying assistant, which is disadvantageous owing to the risk of corrosion.

(10) TABLE-US-00003 TABLE 2 Production of dried hardening accelerators (TH1-a to TH1-h are noninventive comparative examples) Initial Initial mass mass of of Drying additive Dryer temp. Powder H1 [g] assistant [g] exit [° C.] TH1-a 500 — — 60 TH1-b 500 — — 80 TH1-c 500 — — 100 TH1-d 500 — — 120 TH1-e 500 CaCl.sub.2 10.8 60 TH1-f 500 CaCl.sub.2 10.8 80 TH1-g 500 CaCl.sub.2 10.8 100 TH1-h 500 CaCl.sub.2 10.8 120 TH1-m 542.6 NaSO.sub.3CH.sub.3 38.0 80 TH1-n 654.0 Ca(SO.sub.3CH.sub.3).sub.2 45.8 80 TH1-o 620.8 NaSO.sub.3NH.sub.2 43.5 80 TH1-p 609.8 Ca(SO.sub.3NH.sub.2).sub.2 42.7 80 TH1-q 631.8 Ca(SO.sub.3NH.sub.2).sub.2 33.2 80 TH1-r 567.0 Ca(SO.sub.3NH.sub.2).sub.2 59.5 80 TH1-s 670.0 Ca(SO.sub.3NH.sub.2).sub.2 46.9 100 TH1-t 615.4 Ca(SO.sub.3NH.sub.2).sub.2 43.1 110

EXAMPLE 3

(11) Effect of Dried Hardening Accelerators on Hardening

(12) The effect of the hardening accelerators obtained by drying on the hardening was tested on the cement (CEM I Milke 52.5 R) by measurement of the release of heat, using heat flow calorimetry. The hardening accelerator was mixed with the batching water, and the suspension obtained was then mixed with 20 g of the cement. The water-to-cement ratio (w/c) was set at 0.32. The level at which the accelerators under test were metered in table 3 was selected so as to use in each case the same amount of the solid of H1, i.e., 0.6 wt %, based on the cement. Depending on the addition of the drying assistant of the invention, the absolute amount of the accelerator of the invention that is used will vary, with the amount of the solids of H1, based on the cement, as described above, being kept constant. The addition of the additive of the invention accelerates the hardening (defined in H. F. W. Taylor (1997): Cement Chemistry, 2nd edition, p. 212ff). The acceleration factors are summarized in table 3.

(13) TABLE-US-00004 TABLE 3 Dried hardening accelerators, heat flow in the main hydration period (TH1-a to TH1-h are noninventive comparative examples) Cumulative heat Acceleration of hydration after relative to Sample 6 h (J/g) reference (%) CEM I Milke 52.5 R + 0.6 wt % TH 1-a 53.7 132 CEM I Milke 52.5 R + 0.6 wt % TH1-b 60.2 148 CEM I Milke 52.5 R + 0.6 wt % TH1-c 58.6 144 CEM I Milke 52.5 R + 0.6 wt % TH1-d 56.2 138 CEM I Milke 52.5 R + 0.7 wt % TH1-e 86.2 212 CEM I Milke 52.5 R + 0.7 wt % TH1-f 88.3 217 CEM I Milke 52.5 R + 0.7 wt % TH1-g 86.3 212 CEM I Milke 52.5 R + 0.7 wt % TH1-h 82.6 203 CEM I Milke 52.5 R + 0.93 wt % TH1-m 75.0 184 CEM I Milke 52.5 R + 0.93 wt % TH1-n 81.6 200 CEM I Milke 52.5 R + 0.93 wt % TH1-o 81.0 200 CEM I Milke 52.5 R + 0.93 wt % TH1-p 88.1 217 CEM I Milke 52.5 R + 0.84 wt % TH1-q 81.8 201 CEM I Milke 52.5 R + 1.07 wt % TH1-r 87.2 214 CEM I Milke 52.5 R + 0.93 wt % TH1-s 79.9 196 CEM I Milke 52.5 R + 0.93 wt % TH1-t 83.8 206
Examples for the Use of Water-Soluble Sulfonic Salts of Calcium for Producing Calcium Silicate Hydrate Particles

EXAMPLE 4 (INVENTIVE)

(14) Preparation of the Hardening Accelerator Suspension H2

(15) A calcium source was prepared by dissolving 122 g of amidosulfuric acid (purity 100%) in 288.7 g of H.sub.2O, followed by slow addition of 46.7 g of Ca(OH).sub.2 (purity 95%). A silicate source was prepared by dissolving 104.9 g of sodium metasilicate pentahydrate (purity 99%) in 109.7 g of H.sub.2O. A dispersant solution was prepared by weighing out 82.8 g of a solution of polymer 1 (45 wt % strength polymer solution) and 245.1 g of H.sub.2O. The dispersant solution was introduced initially and pumped in circulation through a high-energy mixer with a mixing volume of 20 ml and equipped with a rotor/stator system. In the high-energy mixer, the calcium source and the silicate source are metered completely into the initially introduced solution over the course of 80 minutes, with the rotor/stator system operating at a rotational speed of 8000 rpm. During this procedure, the initially introduced solution is maintained at 20° C.

(16) Preparation of the Hardening Accelerator Suspension H3 (Inventive)

(17) A calcium source was prepared by dissolving 173.3 g of methanesulfonic acid (purity 100%) in 236.7 g of H.sub.2O, followed by slow addition of 46.7 g of Ca(OH).sub.2 (purity 95%). A silicate source was prepared by dissolving 104.9 g of sodium metasilicate pentahydrate (purity 99%) in 109.7 g of H.sub.2O. A dispersant solution was prepared by weighing out 101.9 g of a solution of polymer 1 (45 wt % strength polymer solution), 26.3 g of a solution of polymer 2 (35 wt % strength polymer solution), and 200.3 g of water. The dispersant solution was introduced initially and pumped in circulation through a high-energy mixer with a mixing volume of 20 ml and equipped with a rotor/stator system. In the high-energy mixer, the calcium source and the silicate source are metered completely into the initially introduced solution over the course of 80 minutes, with the rotor/stator system operating at a rotational speed of 8000 rpm. During this procedure, the initially introduced solution is maintained at a temperature of 20° C.

(18) Drying of the Hardening Accelerator Suspensions H2 and H3 (Inventive)

(19) The hardening accelerator suspensions H2 and H3 were dried by spray drying at an exit temperature of 80° C. without addition of a drying assistant. This produced, from suspension H2, the dried hardening accelerator T2, and similarly, from H3, the dried hardening accelerator T3.

(20) Influence of the Hardening Accelerator Suspensions H2 and H3 and of the Dried Hardening Accelerators T2 and T3 on the Hardening of Cementitious Systems

(21) The hardening effect of the hardening accelerators T2 and T3, obtained on drying, was tested on the cement (CEM I Milke 52.5 R) by measurement of the release of heat, using heat flow calorimetry. The hardening accelerator was mixed with the batching water, and the resulting suspension was mixed with 20 g of the cement. The water-to-cement ratio (w/c) was set at 0.32. The metering of the accelerators under test was selected such that in each case the same amount of the solids of H2 and H3 was used, i.e., 0.6 wt % based on the cement. The addition of the additive of the invention accelerates the hardening (defined in H. F. W. Taylor (1997): Cement Chemistry, 2nd edition, p. 212ff). The effect is summarized in table 4.

(22) TABLE-US-00005 TABLE 4 Hardening accelerators H2 and H3 and also dried hardening accelerators T2 and T3; comparison of heats of hydration after 6 h Cumulative heat Acceleration of hydration relative to Powder after 6 h (J/g) reference (%) CEM I Milke 52.5 R (reference) 36.6 — CEM I Milke 52.5 R + 0.6 wt % H2 93.5 255 CEM I Milke 52.5 R + 0.6 wt % T2 80.8 221 CEM I Milke 52.5 R + 0.6 wt % H3 90.2 246 CEM I Milke 52.5 R + 0.6 wt % T3 85.2 233