Additive for hydraulic binder useful to prevent the formation of rust-colored stains at the surface of hydraulic compositions

Abstract

A method for preventing formation of rust-colored stains on the surface of a hydraulic composition includes mixing the hydraulic composition with an additive for hydraulic binder including at least a dialkanolamine including from 2 to 8 carbon atoms, and at least a polyol preferably chosen from a diol, a triol, a tetraol and mixtures thereof. Other uses include a grinding aid for hydraulic binder precursor, and/or improving the compressive strength of a set hydraulic composition.

Claims

1. A method for preventing the formation of rust-colored stains at the surface of a hydraulic composition, said method comprising the step consisting of mixing a hydraulic composition or a constituent of a hydraulic composition with an additive for hydraulic binder comprising: water diisopropanolamine, and a polyol, wherein, in the hydraulic composition, the weight ratio of diisopropanolamine to the hydraulic binder is from 1×10.sup.−4 to 0.0005.

2. The method according to claim 1, wherein the polyol is chosen from a diol, a triol, a tetraol and mixtures thereof.

3. The method according to claim 2, wherein the diol is an alkyleneglycol.

4. The method according to claim 1, wherein the additive for hydraulic binder comprises less than 20% by weight of triisopropanolamine.

5. The method according to claim 1, wherein the hydraulic composition comprises the additive for hydraulic binder, a hydraulic binder, optionally a supplementary cementitious material and optionally a fluidifying agent.

6. The method according to claim 5, wherein the hydraulic binder is a cement.

7. The method according to claim 3, wherein the alkyleneglycol comprises from 1 to 20 carbon atoms.

8. The method according to claim 4, wherein the additive for hydraulic binder is free from triisopropanolamine.

Description

DESCRIPTION OF THE PREFERRED EMBODIMENTS

(1) The following examples illustrate the invention.

EXAMPLES

(2) Methods:

(3) Cement fineness is expressed either in terms of Particle Size Distribution (PSD) with residues (or passing) on reference sieves, or by its specific surface area in Blaine. D10, D50 and D90 were measured by laser light diffraction.

(4) #325 mesh Sieve (i.e. about 44 μm sieve) and #450 mesh Sieve (i.e. about 32.0 μm sieve) were used as reference sieves for the passing tests.

(5) Test Method A of ASTM C 204-05 Standard Test Methods for Fineness of Hydraulic Cement by Air-Permeability Apparatus was used to determine the Blaine Specific Surface Area. The single-operator coefficient of variation for Portland cements has been found to be 1.2%. Therefore, results of two properly conducted tests, by the same operator, on the same sample, should not differ by more than 3.4% of their average.

(6) The ASTM C1565-09 standard was used to determine the relative pack-set tendency of the prepared cements. Low pack set Indexes are sought because the ground cement exhibits a better flowability and is thus easier to process.

(7) The ASTM C 191-13 Standard Test Method was used to determine the time of Setting of Hydraulic Cement by Vicat Needle: The single-operator standard deviation has been found to be 12 min for the initial time of setting throughout the range of 49 to 202 min. Therefore, results of two properly conducted tests by the same operator and with similar paste should not differ from one another by more than 34 min on the Vicat initial time of setting.

(8) The ASTM C 109/C 109 M Standard Test Method (2016) was used for determining the Compressive Strengths of the prepared hydraulic compositions.

(9) The coloration tests were performed as follows. The hydraulic compositions samples were immersed under a head of water of 1 inch (2.54 cm) (corresponding to the half of their heights) during 28 days. The coloration of the surface thereof was then determined with a visual test. 0 means no coloration (i.e. the grey color typical for a hydraulic composition was observed), whereas “+” means that a rust-colored stains were observed on the surface of the prepared hydraulic compositions.

Example 1: Additive for a Cement 1 Free from Supplementary Cementitious Materials

(10) Additives for hydraulic binder having the compositions detailed at table 1 were prepared by mixing the different components.

(11) TABLE-US-00001 TABLE 1 composition of the additives for hydraulic binder 85% wt 85% wt Glycerin DIPA aq. TIPA aq. 98% glycol Acetic % wt sol. sol. TEA**** Amine** DEG min polyol* blend*** TBP Acid Water SP141 22.0 — — 6.0 — 15.0 28.6 20.000 1.000 — 7.4 (invention) SP142 26.0 — — — — 15.0 28.6 20.000 1.000 — 9.4 (invention) S026 — 25.7 — — — 15.0 24.9 26.7  — — 7.7 (comparative) reference — — 19.9 — 68.7 — — — — 11.4 — aq. sol.: aqueous solution *polyol mixture comprising from 0-10% wt of monoethyleneglycol, 0-85% wt of diethyleneglycol, 15-100% wt of triethyleneglycol and 0-15% wt of tetraethyleneglycol **amine mixture comprising 39-100% wt of N-methyl-N-hydroxyethyl-N-hydroxyethoxyethylamine and 10-55% wt of N-methyldiethanolamine (MDEA) ***glycol mixture comprising 3-5% wt of monoethyleneglycol, 75-85% wt of diethyleneglycol, 13-20% wt of triethyleneglycol, about 1% of tetraethyleneglycol and 0-1% wt of water. ****85-99% wt triethanolamine, the balance of the product being distillation residues (ethanolamine oligomers) TBP: tributylphosphate TEA: triethanolamine

(12) A mixture constituted of 93.0% wt of clinker and of 7.0% wt of gypsum was introduced into a grinder, and 0.057% wt of one of the additive for hydraulic binder as defined at table 1 versus the total weight of the mixture was added. The additives for hydraulic binder were thus used as grinding aids. The samples were ground for 147 min at 60 rpm. The 147 min duration is suited to obtain cements, the fineness of which is appropriate to prepare a hydraulic composition.

(13) The hydraulic compositions (mortar) were prepared by mixing 500 g of one of the prepared cements, 1375 g of ASTM-C109 humbolt test sand and 300 g of city water. Hydraulic compositions in the form of 2 inches (5.08 cm) cubes were prepared and removed from the mold after 24 hours.

(14) The features of the prepared cements and of the hydraulic compositions made therefrom are specified at table 2.

(15) TABLE-US-00002 TABLE 2 features of the prepared cements and of the hydraulic compositions made therefrom #325 #450 Sieve Sieve Initial Set Compressive Strength (% (% Blaine Time Pack Set 1 Day 1 Day 7 Day 7 Day 28 Day 28 Day Sample passing) passing) (m.sup.2/kg) (min) Index Stains (MPa) % Ref (MPa) % Ref (MPa) % Ref reference 98.3 93 388 55 3 0 17.9 100.0 33.2 100.0 42.3 100.0 SP026 99 93.4 383 60 2 + 18.2 101.9 35.5 106.8 45.0 106.2 (comparative) S141 99 93.2 388 65 2 0 19.4 108.9 36.0 108.3 45.1 106.5 (invention) S142 98.9 93.3 388 65 2 0 18.5 103.9 35.6 107.1 43.9 103.7 (invention)

(16) Finenesses of the ground cements (both Blaine Specific Surface Area and passing sieves results) and initial set times of hydraulic composition made therefrom were comparable from one sample to the other.

(17) The comparative composition comprising TIPA provided adequate fineness of the ground cement and good 28-day strength of the hydraulic composition obtained therefrom. However, rust-colored stain was observed.

(18) The additive for hydraulic binder used as reference is free from TIPA and did not lead to any coloration of the surface of the hydraulic composition, but the 28-day strength of the hydraulic composition obtained therefrom is lower than the one obtained with the comparative composition comprising TIPA.

(19) Both additives for hydraulic binder according to the invention allowed obtaining a hydraulic composition with a 28-day strength comparable to the one of the comparative composition comprising TIPA, and no coloration of the surface of the hydraulic composition was observed.

Example 2: Additive for a Cement 2 Comprising Supplementary Cementitious Materials

(20) Additive for hydraulic binder having the compositions detailed at table 3 were prepared by mixing the different components.

(21) TABLE-US-00003 TABLE 3 composition of the additives for hydraulic binder 85% wt 85% wt Black DIPA TIPA Glycerin Glycerin Glycol Acetic Pond % wt aq. sol. aq. sol. TEA**** 98% min 99% min polyol* blend*** Acid Dye Water Sp151 25.000 50.3 20.000 4.7 (invention) SP021 46.7 11.7 11.7 29.8 (invention) Reference 42.9 10.1 17.7 0.010 29.2 CGA 22.2 27.2 15.5 11.3 0.01 23.8 (comparative) *polyol mixture comprising from 0-10% wt of monoethyleneglycol, 0-85% wt of diethyleneglycol, 15-100% wt of triethyleneglycol and 0-15% wt of tetraethyleneglycol ***glycol mixture comprising 3-5% wt of monoethyleneglycol, 75-85% wt of diethyleneglycol, 13-20% wt of triethyleneglycol, about 1% of tetraethyleneglycol and 0-1% wt of water. ****85-99% wt triethanolamine, the balance of the product being distillation residues (ethanolamine oligomers) TBP: tributylphosphate TEA: triethanolamine

(22) A mixture constituted of 84.5% wt of clinker, 4.5% wt of gypsum and 11% wt of limestone was introduced into a grinder, and 0.057% wt of one of additives for hydraulic binder as defined at table 3 versus the total weight of the mixture was added. The additives for hydraulic binder were thus used as grinding aids. The samples were ground for 160 min at 60 rpm. The 160 min duration is suited to obtain cements, the fineness of which is appropriate to prepare a hydraulic composition.

(23) The hydraulic compositions (mortar) were prepared by mixing 500 g of one of the prepared cements, 1375 g of ASTM-C109 humbolt test sand and 300 g of city water. Hydraulic compositions in the form of 2 inches (5.08 cm) cubes were prepared and removed from the mold after 24 hours.

(24) The features of the prepared cement and of the hydraulic composition made therefrom are specified at table 4

(25) TABLE-US-00004 TABLE 4 features of the prepared cements and of the hydraulic compositions made therefrom #325 #450 Sieve Sieve Initial (% (% Set Pack Compressive Strength Sample pass- pass- Blaine Time Set D10 D50 D90 1 Day 1 Day 7 Day 7 Day 28 Day 28 Day Tested ing) ing) (m.sup.2/kg) (min) Stains Index (μm)* (μm)* (μm)* (MPa) % Ref (MPa) % Ref (MPa) % Ref SP 151 96.9 90 480 85 0 4 0.906 7.239 26.648 19.3 103.8 32.8 104.8 40.2 108.4 (invention) CGA 96.9 90 476 80 + 3 0.894 7.205 25.945 19.1 102.7 32.7 104.5 40.3 108.6 (comp.) reference 96.3 87.7 462 90 0 4 0.904 6.957 24.929 18.6 100 31.3 100 37.1 100 SP021 96.2 89.8 500 90 0 5 0.876 6.958 25.504 19.4 104.3 32.1 102.6 38.9 104.9 (invention)

(26) Finenesses of the ground cements (both Blaine Specific Surface Area and passing sieves results) and initial set times of hydraulic composition made therefrom were comparable from one sample to the other.

(27) The comparative composition comprising TIPA provided adequate fineness of the ground cement and good 28-day strength of the set hydraulic composition obtained therefrom. However, rust-colored stain was observed.

(28) The additive for hydraulic binder used as reference is free from TIPA and did not lead to any coloration of the surface of the hydraulic composition, but the 28-day strength of the hydraulic composition obtained therefrom is lower than the one obtained with the comparative composition comprising TIPA.

(29) Both additives for hydraulic binder according to the invention allowed obtaining a hydraulic composition with a 28-day strength comparable to the one of the comparative composition comprising TIPA, and no coloration of the surface of the hydraulic composition was observed.