Composition for flowable fire-resistant materials

Abstract

A composition may be suitable for flowable refractory materials and include calcium aluminate cement, a filler, a plasticizer in the form of a copolymer comprising polyether side chains, and a retarder having at least one acid. An article may include such a composition.

Claims

1. A composition suitable for a flowable refractory material, the composition comprising: calcium aluminate cement; a filler; a plasticizer comprising a copolymer comprising a main chain and polyether side chains, wherein the polyether side chains of the copolymer are polyether side chains of structural unit (I)
*-U-(C(O)).sub.k—X-(AlkO).sub.z-W  (I), wherein * is a bonding site to the polymer, U is a chemical bond or an alkylene group comprising 1 to 8 carbon atoms and optionally substituted by at least one carboxyester, carboxyl, phosphono, sulfino, sulfo, sulfamido, sulfoxy, sulfoalkyloxy, sulfinoalkyloxy, and/or phosphonooxy, X is oxygen, sulfur, or NR.sup.1, k is 0 or 1, z is an integer, a mean of which, based on the polymer, is in a range of from 3 to 300, Alk is independently C.sub.2-C.sub.4-alkylene, W is H, a C.sub.1-C.sub.6-alkyl radical, an aryl radical, or Y—F, Y is a linear or branched alkylene group comprising 2 to 8 carbon atoms and optionally bearing a phenyl ring, F is a nitrogen-bonded 5- to 10-membered nitrogen heterocycle optionally comprising, as ring members, in addition to the nitrogen atom and carbon atoms, 1, 2, or 3 additional oxygen, nitrogen, and/or sulfur, where the nitrogen ring members optionally comprise a group R.sup.2, and 1 or 2 carbon ring members optionally form a carbonyl group, R.sup.1 is H, C.sub.1-C.sub.4-alkyl, or benzyl, and R.sup.2 is H, C.sub.1-C.sub.4-alkyl, or benzyl; and a retarder comprising an acid.

2. The composition of claim 1, wherein the main chain (i) consists of at least one structural unit consisting of a carbon chain having at least 16 carbon atoms, or (ii) consists of at least one structural unit consisting of a (C—C—O).sub.n chain, n being number of at least 5, or (iii) consists of at least one structural unit consisting an aromatic or a heteroaromatic system.

3. The composition of claim 1, wherein the copolymer comprises carboxyester, carboxyl, phosphono, sulfino, sulfo, sulfamido, sulfoxy, sulfoalkyloxy, sulfinoalkyloxy, and/or phosphonooxy group.

4. The composition of claim 1, wherein the copolymer is a polycondensation product comprising (II) a structural unit comprising an aromatic or heteroaromatic system and the polyether group, and/or (III) a phosphated structural unit comprising an aromatic or heteroaromatic system.

5. The composition of claim 4, wherein the structural units (II) and (III) have formulae
A-U-(C(O)).sub.k—X-(AlkO).sub.z-W  (II), wherein A is independently an optionally substituted aromatic or heteroaromatic compound comprising 5 to 10 carbon atoms in the aromatic system, further radicals as defined for structural unit (I); ##STR00011## wherein D is independently an optionally substituted aromatic or heteroaromatic compound comprising 5 to 10 carbon atoms in the aromatic system, wherein E is independently N, NH, or O, m is 2 if E is N and m is 1 if E is NH or O, R.sup.3 and R.sup.4 are independently a C.sub.1- to C.sub.10-alkyl radical, C.sub.5- to C.sub.8-cycloalkyl radical, aryl radical, heteroaryl radical, or H, b is independently an integer in a range of from 0 to 300.

6. The composition of claim 1, wherein the acid comprises hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid, acetic acid, citric acid, sulfonic acid, and/or metal salt.

7. The composition of claim 6, wherein the metal salt is present and comprises an aluminum salt.

8. The composition of claim 6, wherein the acid is a sulfonic acid of formula (VII)
R.sup.17—(CH.sub.2).sub.p-SO.sub.3M.sub.a  (VII), wherein R.sup.17 is a C.sub.1-C.sub.20-alkyl radical, C.sub.6-C.sub.10-aryl radical optionally substituted by one or more C.sub.1-C.sub.20-alkyl radicals, NR.sup.18R.sup.19, or a substituent of formula (VIII), ##STR00012## R.sup.18 and R.sup.19 are independently H or C.sub.1-C.sub.23-alkyl, R.sup.20 and R.sup.21 are independently H or C.sub.1-C.sub.20-alkyl, V is —O— or —NH—, R.sup.22 is H or methyl, p is a number in a range of from 0 to 10, M is H, a metal cation, or an ammonium cation, and a is 1 or 1/valence of the metal cation.

9. The composition of claim 8, wherein the acid is a sulfonic acid of formula (VII), wherein R.sup.17 is an unbranched C.sub.1-C.sub.2-alkyl radical or NR.sup.18R.sup.19, R.sup.18 and R.sup.19 are H, R.sup.20 and R.sup.21 are methyl, W is —NH—, R.sup.22 is H, p is a number in a range of from 0 to 2, and M is H.

10. The composition of claim 1, comprising, based on total composition weight: the calcium aluminate cement in a range of from 1.0 to 20.0 wt. %, the filler in a range of from 60.0 to 98.99 wt. %, the plasticizer in a range of from 0.01 to 3.0 wt. %; and the retarder in a range of from 0.01 to 5.0 wt. %.

11. The composition of claim 1, wherein the filler is aluminum oxide.

12. The composition of claim 1, which is free from boron.

13. The composition of claim 1, comprises Portland cement in an amount of less than 3.0 wt. %, based on total composition weight.

14. An article, comprising: the composition of claim 1.

15. A flowable refractory material, comprising: the composition of claim 1.

16. A refractory article, comprising: the composition of claim 1.

Description

EXAMPLES

(1) Materials Used

(2) Tabular Alumina T 60 is the commercial calcined aluminum oxide from Almatis GmbH, having the grain sizes reported in table 1.

(3) Reactive Alumina CL 370 is commercially available from Almatis GmbH.

(4) Ca aluminate cement CA 270 is commercially available from Almatis GmbH.

(5) Plasticizer 1 is the commercial plasticizer Castament FS 10 from BASF Construction Solutions GmbH, which is a pulverulent polymerization product based on polyethylene glycol.

(6) Plasticizer 2 is the commercial plasticizer Castament FW 10 from BASF Construction Solutions GmbH, which is a pulverulent polymerization product based on polyethylene glycol and, in contrast to Castament FS 10, comprises additional lithium ions and therefore leads to accelerated hydration.

(7) Plasticizer 3 is the commercial plasticizer naphthalene sulfonate polymers Flube OS 39 from Bozetto S.p.a.

(8) Boric acid, amidosulfonic acid, phosphoric acid, acetic acid, aluminum chloride, 2-acrylamido-2-methylpropanesulfonic acid, hydrochloric acid, methanesulfonic acid, the acidic ion exchanger Dowex 50 WX 2 and aluminum dihydrogenphosphate are commercially available compounds from Sigma Aldrich.

(9) Production of the Binder Mixtures

(10) Production is effected in a Hobart A 200 pan mixer. All dry components with a total amount of 5000 g are premixed for 60 seconds at a stirring speed of 107 revolutions per minute, before the total amount of mixing water required is added in one step. After the addition of water, the mixture is stirred for a further 4 minutes.

(11) The composition of the dry binder mixtures is summarized in table 1, the added amounts of plasticizer, mixing water and retarder in table 2.

(12) TABLE-US-00001 TABLE 1 Dry components of the binder mixtures Component Proportion [% by weight] Tabular Alumina T 60, 3-6 mm 30 Tabular Alumina T 60, 1-3 mm 15 Tabular Alumina T 60, 0.5-1 mm 10 Tabular Alumina T 60, 0.2-0.6 mm 5 Tabular Alumina T 60, 0-0.2 mm 10 Tabular Alumina T 60, 0-0.045 mm 8 Tabular Alumina T 60, 0-0.02 mm 7 Reactive Alumina CL 370 10 Ca aluminate cement CA 270 5 Total 100

(13) TABLE-US-00002 TABLE 2 Additions of plasticizers, mixing water and retarders Component Proportion [% by weight].sup.1) Plasticizer 1.sup.3) 0.1 Plasticizer 2.sup.3) 0.1 Addition of water 4.9 Addition of retarder 0.0125-0.12.sup.2) .sup.1)Based on the total amount of dry components according to table 1 .sup.2)The precise retarder dosages can be found in table 3 .sup.3)In comparative example 5, only 0.1% by weight of plasticizer 3 is used overall instead, and in comparative example 6 only 0.5% by weight of plasticizer 3 is used overall.

(14) Slump

(15) Four flow cones according to EN 1402-4:2003 are filled with the freshly prepared binder mixture. The slump is determined after 10, 30, 60 and 120 minutes after filling by raising the flow cone and removing material adhering to the wall of the flow cone and carefully adding it to the flowing material. When the material comes to a standstill (two minutes after the flow cone was raised), the diameter of the flow cake is determined in two perpendicular directions. The values in [cm] given in the table correspond to the arithmetic mean of both directions.

(16) Since the internal diameter of the flow cone is 10 cm, a slump of 10 cm means that the material has not moved after raising of the flow cone.

(17) In order to determine the fresh concrete density, the freshly prepared material was slowly filled into a 250 ml plastic beaker and the ratio of intrinsic mass and volume was determined.

(18) Strength Values

(19) Flexural strength and compressive strength according to DIN EN 196-1 were determined 24 hours after mixing, using test specimens having the dimensions 40×40×160 mm.sup.3 which were stored at 20° C. and 65% atmospheric humidity. The values reported in table 3 correspond to arithmetic means of three measured test specimens.

(20) The slumps and strength values summarized in table 3 show that the slumps and strengths of refractory materials having boron-free retarders employing branched with polyalkylene oxide side chains as plasticizer are comparable to the properties of boric acid-containing compositions. A relatively small amount of mixing water is required for this, according to table 2.

(21) The strengths are similar to or better than those in the case of the boric acid-containing system. Compared to the reference without retarder, the processing time is at least 60 minutes, whereas the reference system without retarder can be processed for only 10 minutes.

(22) TABLE-US-00003 TABLE 3 Slump and strength values Flexural tensile Compressive Dosage Slump Slump Slump Slump strength strength No. Retarder [%] 10 min [cm] 30 min [cm] 60 min [cm] 120 min [cm] [MPa] [MPa] C 1 (without) — 22.3 10 — — C 2 Boric acid 0.0125 27   28 11 10 4.6 23 C 3 Boric acid 0.0250 26.5 26.5 26 23.5 4.9 25 C 4 Boric acid 0.0500 24.5 25 23.5 22.5 4.2 24 C 5 Amidosulfonic acid.sup.1) 0.0600 10.sup.3) C 6 Amidosulfonic acid.sup.2) 0.0600 10.sup.3) I 1 Amidosulfonic acid (99.8%) 0.0300 25   26 10 10 4.4 21 I 2 Amidosulfonic acid (99.8%) 0.0600 24   24.5 23 20.5 4.5 22 I 3 Amidosulfonic acid (99.8%) 0.1200 19.5 21 20 20 5.4 25 I 4 Phosphoric acid (85%) 0.0300 25.5 26.5 25.5 25 5.8 31.4 I 5 Acetic acid (99.9%) 0.0600 20.5 21 20.5 16 4.5 21.9 I 6 Aluminum chloride 0.0300 21.5 21.4 20.2 19.1 — — I 7 2-acrylamido-2- 0.1000 22.6 22.3 21.2 19.2 — — methylpropanesulfonic acid I 8 Hydrochloric acid (15%) 0.0150 21.2 21.2 17.8 10 — — I 9 Methanesulfonic acid 0.0600 21.0 22.2 20.4 10.0 — — I 10 Dowex 50 WX 2 (acidic ion 0.6000 26.3 27.0 24.6 10 4.9 24.2 exchanger) I 11 Aluminum dihydrogenphosphate 0.0125 26.7 26.5 10 10 — — (95%) I 12 Aluminum dihydrogenphosphate 0.0250 26.0 25.9 24.6 23.3 5.7 28 (95%) I 13 Aluminum dihydrogenphosphate 0.0500 21.2 21.1 21.0 19.8 — — (95%) .sup.1)0.1% by weight of plasticizer 3 .sup.2)0.5% by weight of plasticizer 3 .sup.3)not processible