Dispersant for inorganic particles

Abstract

The invention relates to dispersants for inorganic particles, preferably for hydraulic binders, which comprises the following structural units: i) at least one triazine structural unit, ii) at least one polyalkylene glycol structural unit, and iii) at least two phosphoric ester structural units on at least one carbon atom of one or more aromatic triazine rings of the formulae (IIa) and/or (IIb):
N(CH.sub.2CH.sub.2OPO.sub.3H.sub.2).sub.2,(IIa)
and
NHCH.sub.2CH.sub.2OPO.sub.3H.sub.2.(IIb) The invention also relates to a process for preparing the dispersants, to building material mixtures comprising one or more dispersants and one or more inorganic binders. The invention relates to the use of the dispersants as a water reducing agent, as a means for reducing the viscosity and for enhancing the early strengths of aqueous inorganic binders, and also to the use as a grinding aid in the production of cement.

Claims

1. Dispersant for inorganic particles, inorganic binders, or hydraulic binders, said dispersant comprising the following structural units i) at least one triazine structural unit, optionally at least one 1,3,5-triazine structural unit, the case of more than one triazine structural unit being referred to as case A and the case of one triazine structural unit being referred to as case B, ii) at least one polyalkylene glycol structural unit, iii) and at least two phosphoric ester structural units, characterized in that, in case A, at least one of the triazine structural units on at least one carbon atom of one or more aromatic triazine rings, is independently substituted by a substituent selected from the general formulae (IIa) and/or (IIb), or, in case B, the triazine structural unit on at least one carbon atom of the aromatic triazine ring, is independently substituted by a substituent selected from the general formulae (IIa) and/or (IIb), where, in cases A and B, the general formulae in each case are
N(CH.sub.2CH.sub.2OPO.sub.3H.sub.2).sub.2(IIa)
and
NHCH.sub.2CH.sub.2OPO.sub.3H.sub.2.(IIb)

2. The dispersant according to claim 1, characterized in that, in case A, at least one of the triazine structural units is substituted on at least one carbon atom of one or more aromatic triazine rings, independently by a substituent selected from NR(R.sup.1), SR and/or OR, or, in case B, the triazine structural unit is substituted on at least one carbon atom of the aromatic triazine ring, independently by a substituent selected from NR(R.sup.1), SR and/or OR, where, in both case A and in case B, R in each case is the same or different and is independently defined as a radical comprising at least one polyalkylene glycol structural unit, and where R.sup.1 is the same or different and is independently defined as H, C.sub.1- to C.sub.20-alkyl radical or a structural unit comprising a polyalkylene glycol structural unit.

3. The dispersant according to claim 2, characterized in that the substituent(s) on the triazine structural unit(s) is/are OR where R is the same or different and is independently defined as a radical comprising at least one polyalkylene glycol structural unit.

4. The dispersant according to claim 1, characterized in that at least one radical which comprises a polyalkylene glycol structural unit and is of general formula (I) -(AO).sub.nR.sup.2 is present in the dispersant, where A is an alkylene having 2 to 18 carbon atoms, where the figures in mol % are based on the total number of moles of all structural units (AO).sub.n in the dispersant, n is an integer from 2 to 500, R.sup.2 is the same or different and is independently H and/or a hydrocarbyl radical.

5. The dispersant according to claim 1, characterized in that the weight ratio of the triazine structural unit(s) i) to the phosphoric ester structural units iii) in the dispersant is between 1/4.5 and 1/12.

6. The Case A dispersant according to claim 1, characterized in that one or more structural unit(s) which connect at least two triazine structural units and are of the general formula (IIIa) and/or (IIIb) is/are present and the general formulae of the structural units (IIIa) and (IIIb) are
Q-(T-triazine).sub.k(IIIa) where k is an integer greater than 1, T is O, NH or S and Q is any hydrocarbyl radical, or an alkylene radical,
(triazine)-U[(CH.sub.2).sub.2N(V)].sub.m(CH.sub.2).sub.2U-(-triazine),(IIIb) where m is an integer from 1 to 6, U is the same or different and is independently O, S and/or NH, V is H and/or triazine.

7. The Case A dispersant according to claim 6, wherein Q is an ethylene radical, and T is NHor O.

8. The Case A dispersant according to claim 1, characterized in that the dispersant contains at least one phosphoric diester structural unit.

9. The Case A dispersant according to claim 8 wherein the dispersant contains a structure which connects at least two triazine structural units, and is of the general formula (IVa)
(triazine)-N(W)(CH.sub.2).sub.2OPO(OH)O(CH.sub.2).sub.2N(W)-(triazine),(IVa) where W is independently CH.sub.2CH.sub.2OPO.sub.3H.sub.2 and/or H.

10. The Case A dispersant according to claim 8, characterized in that the at least one phosphoric diester structural unit corresponds to the general formula (IV)
OPO(OH)O.(IV)

11. The Case A dispersant according to claim 1, characterized in that two triazine structural units are present, one or two polyalkylene glycol structural units are present and 3 to 6 phosphoric ester structural units are present.

12. The Case B dispersant according to claim 1 where only one triazine structural unit is present, characterized in that one or two polyalkylene glycol structural units and two to four phosphoric ester structural units are present.

13. The Case B dispersant according to claim 12, characterized in that the dispersant corresponds to the structure (Va) or (Vb), where (Va) is ##STR00010## and (Vb) is ##STR00011## where R.sup.2 in each of the general formulae (Va) and (Vb) is the same or different and is independently H and/or a hydrocarbyl radical, and W in formula (Va) is independently CH.sub.2CH.sub.2OPO.sub.3H.sub.2 and/or H, and W in formula (Vb) is CH.sub.2CH.sub.2OPO.sub.3H.sub.2.

14. The dispersant according to claim 12, comprising two to four phosphoric ester structural units in the presence of one polyalkylene glycol structural unit, or two phosphoric ester structural units in the presence of two polyalkylene glycol structural units.

15. A process for preparing dispersants according to claim 1, characterized in that 1.) the following reactants are reacted: a) one or more trihalotriazines, b) one or more compounds which comprise at least one polyalkylene glycol unit and react with the halogen substituents of the trihalotriazine, c-1) one or more compound(s) each independently selected from primary and/or secondary amino alcohols, or primary and/or secondary alkanolamines, and c-2) at least one phosphating agent, or alternatively 2.) the reactants a), b) and independently one or more primary and/or secondary amino alcohol(s) C) phosphated on the hydroxyl function(s), optionally phosphated primary and/or secondary alkanolamine(s), are reacted.

16. The process according to claim 15, characterized in that, in the case of process alternative 1.), in a first reaction stage -1), reactant a) is reacted with reactants b) and c-1), optionally under alkaline pH conditions, and, in a second reaction stage (-1), the product obtained from the first reaction stage -1) is phosphated with a phosphating agent c-2) or in that, alternatively in process alternative 2.), reactant a) is reacted with reactants b) and C) under alkaline pH conditions.

17. The process according to claim 16, characterized in that, in process case 1.), the first reaction stage -1) is conducted by reacting reactant a) with b) and then c-1) under alkaline conditions.

18. The process according to claim 15 for preparation of case B) dispersants with only one 1,3,5-triazine structural unit according to the general structural formula Va-1, characterized in that, in process 1.), in a first reaction stage -1), as a), a 2,4,6-trihalo-1,3,5-triazine is reacted with b) a polyalkylene glycol alcohol, and c-1) diethanolamine, and, in the second reaction stage -1), the reaction product obtained from the first reaction stage -1) is phosphated, or alternatively, in case 2.), a) a 2,4,6-trihalo-1,3,5-triazine is reacted with b) a polyalkylene glycol alcohol, optionally a methyl polyethylene glycol, and C) diphosphated diethanol, where the general structural formula Va-1 corresponds to ##STR00012##

19. The process according to claim 15, wherein the 1b) compound comprises only one nucleophilic radical reactive with the halogen substituents of the trihalotriazine.

20. The process according to claim 15, wherein the c-1) compound comprises ethanolamine.

21. The process according to claim 15, wherein the c-2) phosphating agent is selected from phosphoric acid, phosphorus pentoxide, phosphorus pentachloride, POCl.sub.3 and/or polyphosphoric acid.

22. The process according to claim 15, wherein the one or more primary and/or secondary amino alcohol(s) C) phosphated on the hydroxyl function(s) comprise diphosphated and/or monophosphated diethanolamine.

23. The process according to claim 15, characterized in that 1.) the following reactants are reacted: a) one or more trihalotriazines, b) one or more compounds which comprise at least one polyalkylene glycol unit and react with the halogen substituents of the trihalotriazine, c-1) one or more compound(s) each independently selected from primary and/or secondary amino alcohols, or primary and/or secondary alkanolamines having more than one hydroxyl function and only one primary or secondary amino function, and c-2) at least one phosphating agent, or alternatively 2.) the reactants a), b) and independently one or more primary and/or secondary amino alcohol(s) C) phosphated on the hydroxyl function(s), or phosphated primary and/or secondary alkanolamines having more than one phosphated hydroxyl function and only one primary or secondary amino function, are reacted.

24. Building material mixture comprising one or more dispersants according to claim 1 and one or more inorganic binders selected from the group of -calcium sulfate hemihydrate, -calcium sulfate hemihydrate, calcium sulfate in the form of anhydrite, slag sand, fly ash, fumed silica, blast furnace slag, natural pozzolans and/or burnt oil shale, optionally in the presence of (portland) cement with a proportion greater than 40% by weight based on the total amount of the inorganic binder in the inorganic binder.

25. A process for utilizing the dispersants according to claim 1 as water reducing agents of aqueous inorganic binders, selected from the group of -calcium sulfate hemihydrate, -calcium sulfate hemihydrate, calcium sulfate in the form of anhydrite, slag sand, fly ash, fumed silica, blast furnace slag, natural pozzolans and/or burnt oil shale, optionally in the presence of (portland) cement with a proportion greater than 40% by weight based on the total amount of the inorganic binder in the inorganic binder, or for concrete, or for concrete for precast component works, the process comprising mixing said dispersants with at least one of said inorganic binders.

26. A process for utilizing of the dispersants according to claim 1 as a means for reducing the viscosity of aqueous inorganic binders selected from the group of -calcium sulfate hemihydrate, -calcium sulfate hemihydrate, calcium sulfate in the form of anhydrite, slag sand, fly ash, fumed silica, blast furnace slag, natural pozzolans and/or burnt oil shale, optionally in the presence of (portland) cement with a proportion of greater than 40% by weight based on the total amount of the inorganic binder in the inorganic binder, the process comprising mixing said dispersants with at least one of said inorganic binders.

27. A process for comprising utilizing the dispersants according to claim 1 for enhancing the early strengths of aqueous inorganic binders selected from the group of -calcium sulfate hemihydrate, -calcium sulfate hemihydrate, calcium sulfate in the form of anhydrite, slag sand, fly ash, fumed silica, blast furnace slag, natural pozzolans and/or burnt oil shale, optionally in the presence of (portland) cement with a proportion of greater than 40% by weight based on the total amount of the inorganic binder in the inorganic binder, the process comprising mixing said dispersants with at least one of said inorganic binders.

28. A process for comprising utilizing the dispersants according to claim 1 as a grinding aid in the production of cement, the process comprising mixing said dispersants with a clinker or clinker blend.

29. The dispersant according to claim 1, wherein in case A, 2 to 6 triazine structural units are present.

30. The dispersant according to claim 1, wherein 2 to 10 phosphoric ester structural units are present.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a diagram of the calorimetry measurements, which show energy against time.

(2) Mortar Tests

(3) The mortar tests were conducted according to the standard DIN EN 1015-3.

(4) TABLE-US-00002 TABLE 2 Slumps of the inventive polymers in the mortar test Mortar slump (cm) Cement Admixture W/C Temperature Dosage 0 min 10 min 30 min Bernburg 0.54 22.7 0.00% 23.9 22.7 42.5R Bernburg Optima 100 0.46 24.0 0.40% 24.2 23.3 22.6 42.5R (Comp.) Bernburg 1 0.46 23.9 0.20% 24.0 22.2 21.2 42.5R Bernburg 2 0.46 23.9 0.20% 23 22 21.3 42.5R Bernburg 3 0.46 23.6 0.40% 23.2 22 21.5 42.5R Bernburg 4 0.46 24.0 0.30% 24.3 23.3 22.1 42.5R Bernburg 8- 0.46 23.4 0.40% 20 42.5R comparative Bernburg 9 0.46 23.8 0.40% 23.5 22.2 21.3 42.5R Bernburg 10 0.46 24.1 0.40% 23.4 22.4 21.2 42.5R Bernburg 11 0.46 23.7 0.27% 24.7 23.8 22.5 42.5R Bernburg GleniumB233 0.43 18.3 0.32% 23.3 24.6 26.2 42.5R (Comp.) Bernburg 1 0.43 19.7 0.40% 23.2 20.7 42.5R Karlstadt Glenium 0.45 18.2 0.35% 23.2 25.4 28.8 42.5R B233 (Comp.) Karlstadt 1 0.45 19.7 0.50% 23.7 22.2 20.9 42.5R Karlstadt Optima 100 0.46 19.0 0.40% 19.9 42.5R (Comp.) The cements used are purchased from Schwenk (all CEM I). W/C = water/cement ratio

(5) On the basis of these results, it becomes clear that the water needed to plasticize a mortar to a particular slump flow is significantly reduced by the addition of these polymers. If the addition of the plasticizer is dispensed with, a water/cement ratio (W/C) of 0.54 is required to obtain a slump flow of 23.9 cm. In the case of use of an alkali-rich cement (Karlstadt), the good dispersion property is particularly evident. Compared to Optima 100, for some of the inventive polymers, a distinct reduction in the dose required to arrive at a similar slump flow is observed. Comparative example 8 without phosphate groups in the structure enables only a relatively low initial slump flow, even at relatively high dosage. The comparative examples with Glenium B233 from polycarboxylate ether chemistry are approximately comparable with the inventive polymers in terms of action, with better slump retention.

(6) TABLE-US-00003 TABLE 3 Evolution of strength in the mortar Compressive strength Slump flow [N/mm.sup.2] Cement Additive W/C Dosage 0 min 10 min 1 day 28 days Bernburg blank 0.54 24.5 23.5 17.67 42.5R Glenium 0.45 0.095% 24.5 22.5 23.92 63.73 b233 Optima 0.45 0.400% 23.9 23.1 8.69 62.53 100 1 0.45 0.170% 23.9 23.1 23.83 65.02

(7) The strengths of the resulting mortar were tested to DIN EN 196-1.

(8) It is found here that the use of this inventive polymer class has a positive influence on the 1-day and 28-day strengths. Particularly an increased 1-day strength is of particular significance for rapid building progress.

(9) Concrete Tests for Determination of Water Reduction Capacity and of Strengths

(10) The cement used to determine water reduction was a Bernburg CEM I cement.

(11) The slump is a measure of how significantly the concrete cake collapses after the metal cone has been raised (difference in height between the upper edge of the metal cone and the height of the concrete cake after the metal mold has been removed). The slump flow (spread) corresponds to the base diameter of the concrete cake after collapse.

(12) The slump flow is obtained by jolting the spread table, according to DIN EN 12350-5, by lifting and dropping it 15 times. The shear forces which result from the knocking cause further spread of the concrete. The diameter of the concrete cake after the knocking is referred to as the slump flow.

(13) TABLE-US-00004 TABLE 4 Evolution of strength in the concrete Slump flow Slump Compressive Bernburg CEM I 42.5 R [cm] [cm] strength Dosage 10 10 [N/mm.sup.2] Additive W/C [%] 0 min min 0 min min 24 hours blank 0.55 47.5 45.5 14 12 14.35 OPTIMA 0.45 0.60 58 58 22 23 not 100 measurable No. 1 0.45 0.40 58 51.5 22.5 18 25.05

(14) This example shows that the results from the mortar tests are reflected in the concrete tests. The early strength of a concrete dispersed with the inventive structure (No. 1) has a much higher value compared to, for example, OPTIMA 100. Under these conditions, the strength is still not measurable after 24 hours since the concrete is still free-flowing.

(15) TABLE-US-00005 TABLE 5 Evolution of strength in a concrete with limestone filler Compressive strength Monselice A/LL + limestone powder as filler material [N/mm.sup.2] Additive W/C Dosage [%] 24 h 1 0.48 0.78 25.3 4 0.48 1.1 27.7 Glenium B233 0.48 0.34 29.5 OPTIMA 100 0.48 0.78 1.9 Blank 0.55 14.35

(16) With increasing side chain length (rising chain length of the polyalkylene glycol in the sequence of inventive examples 3, 1, 4), the 1-day strength rises.

(17) Concrete Tests for Determination of the Plastic Viscosities of the Fresh Concrete

(18) The cement used for the viscosities was a CEM II/A-LL 42.5R from the Monselice cement works.

(19) Composition of the concrete: 400 kg of cement filler: 50 kg of limestone powder, temperature: 20 C.

(20) The slump is a measure of how significantly the concrete cake collapses after the metal cone has been raised (difference in height between the upper edge of the metal cone and the height of the concrete cake after the metal mold has been removed). The slump flow corresponds to the base diameter of the concrete cake after collapse.

(21) The slump flow is obtained by jolting the spread table, according to DIN EN 12350-5, by lifting and dropping it 15 times. The shear forces which result from the knocking cause further spread of the concrete. The diameter of the concrete cake after knocking is referred to as the slump flow.

(22) As already in the mortar, the concrete shows much better processibility as result of addition of the inventive polymer.

(23) Apart from the plasticization, another significant factor for the use as stipulated is the viscosity of the fresh concrete. The viscosity is a measure of the pumpability and processibility of the fresh concrete. Lower values lead to better processibility and hence also to better pumpability (Gleitrohr-Rheometer: Ein Verfahren zur Bestimmung der Flieeigenschaften von Dickstoffen in Rohrleitungen [Sliding pipe rheometer: A method to establish the flow properties of high viscous media in pipelines], thesis by Dr. Knut Jens Kasten, TU Dresden. Shaker Verlag; 1.sup.st ed. (July 2010)).

(24) Commercial superplasticizers are often comb polymers with polyethylene glycol side chains (PEG side chains), for example Glenium B233. However, these plasticizers, when used as water reducers, lead to high plastic viscosities of the fresh concrete. This makes it more difficult to pump the fresh concrete and to place it into molds.

(25) The plastic viscosities of the fresh concrete were measured in an IKAR rheometer (reference: E. P. Koehler, D. W. Fowler (2007). ICAR Mixture Proportioning Procedure for SCC International Center for Aggregates Research, Austin, Tex.).

(26) In order to obtain comparable results, the amount of additive is dosed such that all fresh concretes have a slump of 23 cm after 5 minutes to DIN EN 12350.

(27) The water/cement ratios are set to 0.48 and the measurement is conducted after 5 minutes.

(28) TABLE-US-00006 TABLE 6 Viscosities of the inventive plasticizers in the concrete Monselice A/LL + limestone powder Plastic viscosity Additive W/C Pa*s 1 0.48 120.4 3 0.48 76.9 4 0.48 136.8 OPTIMA 100 0.48 106.8 Glenium B233 0.48 142.1

(29) The viscosity of the blank cannot be measured adequately since much higher W/C ratios would otherwise have to be used here.

(30) The inventive dispersants plasticize concretes and enable achievement particularly of low viscosities of the concrete. Relatively long side chains in the inventive polymers lead to a slight rise in the viscosity of the fresh concrete. However, the viscosities in each case are below those of the polycarboxylate ethers. As is evident from the values, the inventive polymers provide a good way of producing fresh concretes with low WIC ratios and low viscosities.

(31) Results of the Grinding of Clinker for Production of Cement:

(32) In the grinding operations, additive No. 1 of table 1 is added in liquid form in a dosage of 500 ppm (dosage is based on the solids content) to 10 kg of clinker (Mergelstetten clinker), and ground at a temperature of 120 C. for 80 minutes. The mill used is a heatable laboratory ball mill from Cemtec (Labbas1). For comparison, the same clinker is ground under analogous conditions, but without addition of an additive (blank). Compared to the blank, it is possible in the experiment to identify an increase in the Blaine value and a rise in the early strength after 24 hours. The more finely ground particles (higher Blaine value) can also explain the better evolution of strength. Both analysis parameters demonstrate the efficiency of the inventive dispersants as grinding aids.

(33) The mortar tests were conducted with the cement produced by the above process at a W/C ratio of 0.5 and a sand/cement ratio of 3. No further additives were added. The strengths and slump flows were determined according to standards DIN EN 1015-3 and DIN EN 196-1.

(34) TABLE-US-00007 Flexural Compressive Blaine Slump flow strength after strength after [cm.sup.2/g] after 4 min 24 h 24 h Blank (comp.) 3907 20.2 cm 2.87 N/mm.sup.2 13.05 N/mm.sup.2 No. 1 4252 20.4 cm 3.29 N/mm.sup.2 13.54 N/mm.sup.2