U.S. patent application number 11/132361 was filed with the patent office on 2005-09-29 for method for improving the mechanical strength, particularly the strength "at young ages" of cement matrices, and the cement matrices obtained thereby.
This patent application is currently assigned to COATEX S.A.S.. Invention is credited to Gonnon, Pascal, Jacquemet, Christian, Kensicher, Yves.
Application Number | 20050215671 11/132361 |
Document ID | / |
Family ID | 8855713 |
Filed Date | 2005-09-29 |
United States Patent
Application |
20050215671 |
Kind Code |
A1 |
Gonnon, Pascal ; et
al. |
September 29, 2005 |
Method for improving the mechanical strength, particularly the
strength "at young ages" of cement matrices, and the cement
matrices obtained thereby
Abstract
Cements or hydraulic binders may be prepared by adding an
aqueous suspension comprising a ground mineral filler and at least
one grinding aid agent to a cement or hydraulic binder. The
resulting cement or hydraulic binder has very appreciably improved
mechanical properties, particularly the property of "strength at
young ages." The grinding aid agent may be a natural or synthetic
homopolymer and/or copolymer.
Inventors: |
Gonnon, Pascal; (Villeneuve,
FR) ; Kensicher, Yves; (Lozanne, FR) ;
Jacquemet, Christian; (Lyon, FR) |
Correspondence
Address: |
OBLON, SPIVAK, MCCLELLAND, MAIER & NEUSTADT, P.C.
1940 DUKE STREET
ALEXANDRIA
VA
22314
US
|
Assignee: |
COATEX S.A.S.
GENAY
FR
|
Family ID: |
8855713 |
Appl. No.: |
11/132361 |
Filed: |
May 19, 2005 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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11132361 |
May 19, 2005 |
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10452381 |
Jun 3, 2003 |
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10452381 |
Jun 3, 2003 |
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09983719 |
Oct 25, 2001 |
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6713553 |
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Current U.S.
Class: |
524/5 ; 524/431;
524/445; 524/447; 524/8 |
Current CPC
Class: |
C04B 24/165 20130101;
C04B 40/0028 20130101; C04B 2103/52 20130101; C04B 40/0039
20130101; C04B 24/2694 20130101; C04B 2111/70 20130101; C04B
20/0084 20130101; C04B 24/2647 20130101; C04B 2201/05 20130101;
C04B 24/2658 20130101; C04B 24/267 20130101; C04B 2111/0075
20130101; C04B 24/246 20130101; C04B 2103/0099 20130101; Y02W 30/91
20150501; C04B 28/02 20130101; Y02W 30/94 20150501; C04B 20/026
20130101; C04B 20/026 20130101; C04B 14/28 20130101; C04B 2103/52
20130101; C04B 24/2658 20130101; C04B 2103/52 20130101; C04B
24/2647 20130101; C04B 2103/52 20130101; C04B 24/2694 20130101;
C04B 2103/52 20130101; C04B 40/0039 20130101; C04B 14/28 20130101;
C04B 28/02 20130101; C04B 2103/52 20130101; C04B 40/0039 20130101;
C04B 14/28 20130101; C04B 24/2694 20130101; C04B 28/02 20130101;
C04B 28/02 20130101; C04B 18/141 20130101; C04B 24/2647 20130101;
C04B 2103/52 20130101; C04B 24/2647 20130101; C04B 20/0084
20130101; C04B 14/02 20130101; C04B 2103/0099 20130101; C04B 24/24
20130101; C04B 40/0039 20130101; C04B 20/008 20130101; C04B 28/02
20130101; C04B 2103/52 20130101; C04B 40/0039 20130101; C04B 20/008
20130101; C04B 24/24 20130101; C04B 28/02 20130101; C04B 40/0039
20130101; C04B 20/008 20130101; C04B 24/32 20130101; C04B 28/02
20130101; C04B 40/0039 20130101; C04B 20/008 20130101; C04B 24/26
20130101; C04B 28/02 20130101; C04B 40/0039 20130101; C04B 20/008
20130101; C04B 24/161 20130101; C04B 28/02 20130101; C04B 40/0039
20130101; C04B 20/008 20130101; C04B 24/243 20130101; C04B 28/02
20130101; C04B 40/0039 20130101; C04B 20/008 20130101; C04B 24/2605
20130101; C04B 28/02 20130101; C04B 40/0039 20130101; C04B 20/008
20130101; C04B 24/282 20130101; C04B 28/02 20130101; C04B 40/0039
20130101; C04B 20/008 20130101; C04B 24/2652 20130101; C04B 28/02
20130101 |
Class at
Publication: |
524/005 ;
524/431; 524/445; 524/447; 524/008 |
International
Class: |
C08K 003/00 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 25, 2000 |
FR |
00 13661 |
Claims
1. A method of preparing a cement matrix or hydraulic binder,
comprising: adding an aqueous suspension comprising a ground
mineral filler and at least one grinding aid agent to a cement or
hydraulic binder.
2. The method according to claim 1, wherein the grinding aid agent
comprises at least one member selected from the group consisting of
natural homopolymers, synthetic homopolymers, natural copolymers,
synthetic copolymers and mixtures thereof.
3. The method according to claim 2, wherein the grinding aid agent
comprises synthetic homopolymers, copolymers or mixtures thereof
prepared by polymerizing ethylenically unsaturated monomers, by
polycondensation, or by ring opening polymerisation.
4. The method according to claim 1, wherein the grinding aid agent
comprises a polymer prepared by polymerizing at least one
ethylenically unsaturated monomer, comprising at least one anionic
monomer.
5. The method according to claim 4, wherein said polymer is
prepared by polymerizing at least two ethylenically unsaturated
monomers comprising at least one anionic monomer and at least one
non-ionic monomer.
6. The method according to claim 4, wherein said polymer is
prepared by polymerizing at least two ethylenically unsaturated
monomers comprising at least one anionic monomer and at least one
member selected from the group consisting of alkoxy-polyalkylene
glycol ethylenic ester, aryloxy-polyalkylene glycol ethylenic
ester, alkylaryloxy-polyalkylene glycol ethylenic ester,
arylalkyloxy-polyalkylene glycol ethylenic ester,
alkoxy-polyalkylene glycol ethylenic ether, aryloxy-polyalkylene
glycol ethylenic ether, alkylaryloxy-polyalkylene glycol ethylenic
ether, arylalkyloxy-polyalkylene glycol ethylenic ether,
alkoxy-polyalkylene glycol ethylenic urethane monomer,
aryloxy-polyalkylene glycol ethylenic urethane monomer,
alkylaryloxy-polyalkylene glycol ethylenic urethane monomer,
arylalkyloxy-polyalkylene glycol ethylenic urethane monomer, and
mixtures thereof.
7. The method according to claim 4, wherein said polymer is
prepared by polymerizing at least two ethylenically unsaturated
monomers comprising at least one anionic monomer and at least one
ethylenic monomer having at least two polymerizable double
bonds.
8. The method according to claim 4, wherein said polymer is
prepared by polymerizing at least two ethylenically unsaturated
monomers comprising at least one anionic monomer and at least one
cationic monomer.
9. The method according to claim 1, wherein the grinding aid agent
comprises a polymer prepared by polymerizing ethylenically
unsaturated monomers comprising by weight: a) 2% to 100% of at
least one anionic monomer, b) 0% to 50% of at least one non-ionic
monomer, c) 0% to 95% of at least one member selected from the
group consisting of alkoxy-polyalkylene glycol ethylenic ester,
aryloxy-polyalkylene glycol ethylenic ester,
alkylaryloxy-polyalkylene glycol ethylenic ester,
arylalkyloxy-polyalkylene glycol ethylenic ester,
alkoxy-polyalkylene glycol ethylenic ether, aryloxy-polyalkylene
glycol ethylenic ether, alkylaryloxy-polyalkylene glycol ethylenic
ether, arylalkyloxy-polyalkyle- ne glycol ethylenic ether,
alkoxy-polyalkylene glycol ethylenic urethane monomer,
aryloxy-polyalkylene glycol ethylenic urethane monomer,
alkylaryloxy-polyalkylene glycol ethylenic urethane monomer,
arylalkyloxy-polyalkylene glycol ethylenic urethane monomer, and
mixtures thereof, d) 0% to 3% of one or more ethylenic monomers
having at least two polymerizable double bonds, and e) 0% to 98% of
at least one cationic monomer, wherein the total of monomers a),
b), c), d) and e) is equal to 100%.
10. The method according to claim 4, wherein the ethylenically
unsaturated monomer comprises at least one monomer selected from
the group consisting of acrylic acid, methacrylic acid, itaconic,
crotonic, fumaric acid, maleic anhydride, isocrotonic acid,
aconitic acid, mesaconic acid, sinapic acid, undecylenic acid,
angelic acid, 2-acrylamido-2-methyl-1-pro- pane sulphonic acid,
2-methacrylamido-2-methyl-1-propane sulphonic acid,
3-methacrylamido-2-hydroxy-1-propane sulphonic acid, allylsulphonic
acid, methallylsulphonic acid, allyloxybenzene sulphonic acid,
methallyloxybenzene sulphonic acid,
2-hydroxy-3-(2-propenyloxy)propane sulphonic acid,
2-methyl-2-propene-1-sulphonic acid, ethylene sulphonic acid,
propene sulphonic acid, 2-methyl propene sulphonic acid, styrene
sulphonic acid, vinyl sulphonic acid, sodium methallylsulphonate,
sulphoethyl acrylate, sulphopropyl acrylate, sulphoethyl
methacrylate, sulphopropyl methacrylate, sulphomethacrylamide,
sulphomethylmethacrylami- de, alkylene glycol acrylate phosphate,
alkylene glycol acrylate phosphonate, alkylene glycol acrylate
sulphate, alkylene glycol acrylate sulphonate, alkylene glycol
methacrylate phosphate, alkylene glycol methacrylate phosphonate,
alkylene glycol methacrylate sulphate, alkylene glycol methacrylate
sulphonate, vinyl phosphonate and mixtures thereof.
11. The method according to claim 4, wherein said polymer is
prepared by polymerizing at least two ethylenically unsaturated
monomers comprising at least one anionic monomer and at least one
non-ionic monomer selected from the group consisting of acrylamide,
methacrylamide, a derivative of acrylamide, a derivative of
methacrylamide, C.sub.1 to C.sub.40 acrylic acid alkyl-esters,
C.sub.1 to C.sub.40 methacrylic acid alkyl-esters, vinyl acetate,
vinylpyrrolidone, styrene, .alpha.-methyl-styrene and mixtures
thereof.
12. The method according to claim 4, wherein said polymer is
prepared by polymerizing at least two ethylenically unsaturated
monomers comprising at least one anionic monomer and at least one
monomer selected from the group consisting of alkoxy-polyalkylene
glycol ethylenic urethane monomer, aryloxy-polyalkylene glycol
ethylenic urethane monomer, alkylaryloxy-polyalkylene glycol
ethylenic urethane monomer, arylalkyloxy-polyalkylene glycol
ethylenic urethane monomer, an alkoxy-polyalkylene glycol ethylenic
ester monomer, aryloxy-polyalkylene glycol ethylenic ester monomer,
alkylaryloxy-polyalkylene glycol ethylenic ester monomer,
arylalkyloxy-polyalkylene glycol ethylenic ester monomer, an
oxyalkylated, oxyarylated, oxyarylalkylated or oxyalkylarylated
alkoxy-, aryloxy-, alkylaryloxy- or arylalkyloxy-acrylate or
methacrylate or hemimaleate having an alkylene, arylene,
alkylarylene or arylalkylene oxide number between 1 and 120; an
alkoxy-polyalkylene glycol ethylenic ether monomer,
aryloxy-polyalkylene glycol ethylenic ether monomer,
alkylaryloxy-polyalkylene glycol ethylenic ether monomer,
arylalkyloxy-polyalkylene glycol ethylenic ether monomer and
mixtures thereof.
13. The method according to claim 4, wherein said polymer is
prepared by polymerizing at least two ethylenically unsaturated
monomers comprising at least one anionic monomer and at least one
ethylenic monomer having at least two polymerizable double bonds
which is selected from the group consisting of ethylene glycol
dimethacrylate, divinylacetylene, divinylbenzene,
trimethylolpropanetriacrylate, allyl acrylate,
methylene-bis-acrylamide, methylene-bis-methacrylamide,
tetrallyloxyethane, triallylcyanurates, allyl ethers prepared from
polyols and mixtures thereof.
14. The method according to claim 13, wherein the polyols are
selected from the group consisting of pentaerythritol, sorbitol,
sucrose and mixtures thereof.
15. The method according to claim 4, wherein said polymer is
prepared by polymerizing at least two ethylenically unsaturated
monomers comprising at least one anionic monomer and at least one
cationic monomer selected from the group consisting of quarternized
or unquarternized methacrylamido propyl trimethyl ammonium chloride
or sulfate or the corresponding acrylates or acrylamides,
quarternized or unquarternized trimethyl ammonium ethyl
methacrylate chloride or sulfate or the corresponding acrylates or
acrylamides, dimethyldiallyl ammonium chloride and mixtures
thereof.
16. The method according to claim 4, wherein the anionic monomer is
selected from the group consisting of acrylic acid, methacrylic
acid, 2-acrylamido-2-methyl-1-propane sulphonic acid,
2-methacrylamido-2-methyl- -1-propane sulphonic acid,
3-methacrylamido-2-hydroxy-1-propane sulphonic acid, allylsulphonic
acid, methallylsulphonic acid, allyloxybenzene sulphonic acid,
methallyloxybenzene sulphonic acid,
2-hydroxy-3-(2-propenyloxy)propane sulphonic acid,
2-methyl-2-propene-1-sulphonic acid, ethylene sulphonic acid,
propene sulphonic acid, 2-methyl sulphonic acid, styrene sulphonic
acid, vinyl sulphonic acid, sodium methallylsulphonate;
sulphopropyl acrylate, sulphopropyl methacrylate,
sulphomethylacrylamide, sulphomethylmethacrylamide, alkylene glycol
acrylate phosphate, alkylene glycol acrylate phosphonate, alkylene
glycol acrylate sulphate, alkylene glycol acrylate sulphonate,
alkylene glycol methacrylate phosphate, alkylene glycol
methacrylate phosphonate, alkylene glycol methacrylate sulphate,
alkylene glycol methacrylate sulphonate, itaconic acid, maleic
anhydride, sodium methallylsulphonate, styrene sulphonic acid and
mixtures thereof.
17. The method according to claim 4, wherein the anionic monomer is
selected from the group consisting of acrylic acid, methacrylic
acid, 2-acrylamido-2-methyl-1-propane sulphonic acid, ethylene
sulphonic acid, propene sulphonic acid, 2-methyl sulphonic acid,
ethylene glycol methacrylate phosphate, a ethylene glycol acrylate
phosphate and mixtures thereof.
18. The method according to claim 5, wherein the non-ionic monomer
is selected from the group consisting of ethyl acrylate, acrylamide
and mixtures thereof.
19. The method according to claim 6, wherein the alkoxy-, aryloxy-,
alkylaryloxy- or arylalkyloxy-polyalkylene glycol ethylenic
urethane monomer is selected from the group consisting of a) the
reaction products of alkyloxy-polyalkylene glycol with a
polymerizable unsaturated isocyanate; and b) the reaction products
of methoxy-polyethylene glycol with an acrylic, methacrylic, vinyl
or allyl isocyanate; wherein the polyethylene glycol has a
molecular weight greater than 300.
20. The method according to claim 6, wherein the alkoxy-, aryloxy-,
alkylaryloxy- or arylalkyloxy-polyalkylene glycol ethylenic ester
monomer is selected from the group consisting of alkoxy-, aryloxy-,
alkylaryloxy- or arylalkyloxy-polyalkylene glycol acrylates,
methacrylates or hemialeates; oxyalkylated, oxyarylated,
oxyarylalkylated or oxylalkylarylated alkoxy-, aryloxy-,
alkylaryloxy- or arylalkyloxy-polyalkylene glycol acrylates,
methacrylates or hemialeates having alkylene, arylene, alkylarylene
or arylalkylene oxide numbers between 1 and 120; and
alkyloxy-polyethylene glycol acrylates, methacrylates or
hemialeates, wherein the polyethylene glycol has a molecular weight
greater than 300.
21. The method according to claim 3, wherein the grinding aid agent
comprises a homopolymer of acrylic acid or methacrylic acid.
22. The method according to claim 3, wherein the grinding aid agent
comprises a homopolymer, a copolymer or a mixture of a homopolymer
and a copolymer of at least one ethylenically unsaturated cationic
monomer selected from the group consisting of quaternized or
unquarternized methacrylamido propyl trimethyl ammonium chloride or
sulfate or a corresponding acrylate or acrylamide, quaternized or
not, quaternized or unquarternized trimethyl ammonium ethyl
methacrylate chloride or sulfate or a corresponding acrylate or
acrylamide, and dimethyldiallyl ammonium chloride.
23. The method according to claim 3, wherein the polymers prepared
by polycondensation or by ring opening polymerization are selected
from the group consisting of polyaspartate, a derivative of
polyaspartate, polylactates, water-soluble polyesters, polyamides,
polylactones and mixtures thereof.
24. The method according to claim 3, wherein the grinding aid agent
is fractionated subsequent to polymerizing.
25. The method according to claim 2, wherein the grinding aid agent
has a completely acidic form.
26. The method according to claim 2, wherein the grinding aid agent
is partially or completely neutralized by one or more
neutralization agents having a monovalent function or polyvalent
function.
27. The method according to claim 26, wherein the neutralization
agent having a monovalent function is selected from the group
consisting of compounds containing alkaline cations, primary
aliphatic amines, secondary aliphatic amines, cyclic amines and
mixtures thereof.
28. The method according to claim 27, wherein the alkaline cations
are selected from the group consisting of sodium, potassium,
lithium, and ammonium, and wherein the primary aliphatic amines,
secondary aliphatic amines, cyclic amines and mixtures thereof are
selected from the group consisting of ethanolamines,
monoethylamine, diethylamine, cyclohexylamine and mixtures
thereof.
29. The method according to claim 26, wherein the neutralisation
agent having a polyvalent function is selected from the group
consisting of compounds containing divalent alkaline-earth cations,
compounds containing trivalent cations, compounds containing
cations having a valency higher than trivalent and mixtures
thereof.
30. The method according to claim 29, wherein the divalent
alkaline-earth cations are selected from the group consisting of
magnesium, calcium, and zinc, and wherein the trivalent cation is
aluminium.
31. The method according to claim 1, wherein the mineral filler is
selected from the group consisting of ultrafine fillers having a
median diameter less than or equal to 20 .mu.m measured with a
Cilas.TM. 850 or Sedigraph.TM. 5100 type granulometer.
32. The method--according to claim 1, wherein the mineral filler is
selected from the group consisting of natural calcium carbonates,
chalk, calcite, marble, limy rocks, precipitated calcium carbonate,
barium carbonate, dolomite, talc, ground silica, silica, fumed
silica, fumed titanium dioxide, diatomites, iron oxides, manganese
oxides, titanium dioxide, chalk, kaolin, meta-kaolin, clays, mica,
plasters, fly ash, slag, calcium sulphate, zeolites, basalt, barium
sulphate, aluminium trihydroxide and mixtures thereof.
33. The method according to claim 1, wherein the aqueous suspension
has a concentration of dry matter ranging from 10% to 85% by
weight.
34. A cement matrix or a hydraulic binder, prepared by the method
of claim 1.
35. A cement matrix or hydraulic binder, prepared by the method of
claim 2.
36. A cement matrix or hydraulic binder, prepared by the method of
claim 4.
37. A cement matrix or hydraulic binder, prepared by the method of
claim 5.
38. A cement matrix or hydraulic binder, prepared by the method of
claim 7.
39. A cement matrix or hydraulic binder, prepared by the method of
claim 8.
40. A cement matrix or hydraulic binder, prepared by the method of
claim 9.
41. A cement matrix or hydraulic binder, prepared by the method of
claim 21.
42. A cement matrix or hydraulic binder, prepared by the method of
claim 22.
43. A cement matrix or hydraulic binder, prepared by the method of
claim 23.
44. A cement matrix or hydraulic binder, prepared by the method of
claim 24.
45. A cement matrix or hydraulic binder, prepared by the method of
claim 25.
46. A cement matrix or hydraulic binder, prepared by the method of
claim 26.
47. A cement matrix or hydraulic binder, prepared by the method of
claim 32.
48. A concrete, comprising the cement matrix or hydraulic binder
according to claim 34.
49. A mortars comprising the cement matrix or hydraulic binder
according to claim 34.
50. A hydraulic concrete, comprising: the cement matrix or
hydraulic binder according to claim 34.
51. A grout, comprising: the cement matrix or hydraulic binder
according to claim 34.
52. A composition based on cement and/or semihydrate calcium
sulphate, comprising: the cement matrix or hydraulic binder
according to claim 34.
53. A building, offshore construction, bridge petroleum cement or
road, comprising: the cement matrix or hydraulic binder according
to claim 34.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to suspensions of mineral
fillers, preferably calcium carbonates, and more preferably ground
fillers, for example ground calcium carbonates, and additives for
producing such suspensions, for example grinding aid agents. The
grinding aid agents of the present invention provide suspensions of
fillers with improved mechanical properties, particularly the
properties of "strength at young ages" of cement matrices or
hydraulic binders, or more particularly hydraulic concretes,
prepared with these suspensions.
[0003] The present invention also relates to mortars, concretes and
other compositions based on cement and/or semi-hydrate calcium
sulphate, i.e., hydraulic compounds or binders.
[0004] 2. Discussion of the Background
[0005] It is known that cement matrices such as concretes, mortars,
grouts, etc, more particularly hydraulic concretes, are used in two
main applications: ready-for-use concretes and prefabricated
products. In addition, it is known that concrete is composed
essentially of a cement and an aggregate as well as water and
admixtures or additives.
[0006] By granulometry, aggregates are classified into several
categories known to those skilled in the art, and defined by the
French standard XP P 18-540.
[0007] In this standard, the families of aggregates comprise:
[0008] 0/D fillers, where D<2 mm, and at least 70% of the
aggregate passes through a 0.063 mm screen,
[0009] 0/D fine sands, where D.ltoreq.1 mm, and less than 70% of
the aggregate passes through a 0.063 mm screen,
[0010] 0/D sands, where 1<D.ltoreq.6.3 mm,
[0011] gravels, where D>6.3 mm,
[0012] d/D fine gravels, where d>1 mm and D.ltoreq.125 mm,
[0013] d/D ballasts, where d>25 mm and D.ltoreq.50 mm,
[0014] with d and D as defined in this standard.
[0015] Such fillers may include ultra-fines which are defined as
fillers having a median diameter less than or equal to 20 m
measured by means of a Cilas.TM. 850 or Sedigraph.TM. 5100 type
granulometer (selected according to the granulometry of the filler
to be measured). Examples of fillers are, for example, blast
furnace cast vitrified slags, fly ash and other additions of silica
of high fineness, or calcareous additions such as calcium
carbonate.
[0016] The incorporation, in cement matrices or hydraulic binders,
of fumed silica or siliceous additions, or calcareous additions
such as calcium carbonate, is also known. In particular, it is
known that calcium carbonate may be used, either as a dispersion in
water, or in an aqueous medium without dispersant.
[0017] In particular, WO 99/47468 describes the use of calcium
carbonate in the form of an aqueous dispersion for preparing
concretes. This document is an example of preparing a concrete
having a more or less acceptable compromise between ease of
handling and resistance to premature aging. However, WO 99/47468
only describes incorporating a dispersant as a liquefier for
improving fluidity, which is akin to the known functions of
additives in the prior art.
[0018] EP 0 271 435, EP 0 725 043 and U.S. Pat. No. 5,614,017
describe the use of plasticizers in cements, which improve the
compressive strength, or reduce shrinkage, or increase the
workability time, measured with an Abrams cone, also referred to as
"slump". In EP 0 271 435, the additive acts as a water reducer,
which is perfectly in accord with the desirability of having a
water/cement (W/C) ratio which is as low as possible in order to
improve mechanical strength. In EP 0 725 043, the plasticizer is
used at a very low concentration and the technical problem posed is
completely different from that of the present invention, and as in
U.S. Pat. No. 5,614,017. In the three cases, the aggregate is of
the 0/D filler type (as defined above), the calcium carbonate is
used as a dry powder rather than in dispersion, and the addition of
the admixture is effected at the time of preparation of the
concrete, that is to say subsequent to, rather than before the
preparation of the concrete.
[0019] It is also known that admixtures can be used for
deflocculating the cement paste and/or reducing the quantity of
water in the cement. In this regard, it is known that if the
proportion of water increases in a cement matrix or hydraulic
binder, the mechanical strength is reduced. One of skill in the
art, therefore, always endeavours, in their formulations, to reduce
the water/cement ratio (W/C). However, one of skill in the art also
knows that, if the proportion of water increases in a cement matrix
or hydraulic binder, the workability thereof (that is to say its
ability to be handled, pumped, etc) increases. Thus, one of skill
in the art is therefore very often forced to seek a compromise
between the mechanical properties and workability of such cement
matrices or hydraulic binders.
[0020] One of the most important mechanical properties of cement
matrices or hydraulic binders, for one of skill in the art,
concerns the "strength at young ages" of the cement matrix or
hydraulic binder. This property is defined as the change in the
compressive strength curve, according to the age of preparation of
the cement matrix or hydraulic binder, in the region of from 0
hours to 7 days following the preparation of the cement matrix or
hydraulic binder. Normally, a measurement is made at 2 days and 7
days.
[0021] As discussed above, there is an important and recognised
need for significantly increasing the strength at young ages
property, without negatively affecting other advantageous
properties, such as for example workability.
SUMMARY OF THE INVENTION
[0022] Accordingly, it is an object of the present invention to
provide a method of preparing a cement matrix or hydraulic binder
comprising adding an aqueous suspension comprising a ground mineral
filler and at least one grinding agent to cement or hydraulic
binder. It is yet another object of the present invention to
provide a cement matrix or hydraulic binder, prepared by combining
a cement or hydraulic binder, and an aqueous suspension comprising
at least one ground mineral filler and at least one grinding aid
agent.
DETAILED DESCRIPTION OF THE INVENTION
[0023] Thus, in a first embodiment, the present invention provides
a method of preparing a cement matrix or hydraulic binder
comprising adding an aqueous suspension comprising a ground mineral
filler and at least one grinding agent to cement or hydraulic
binder. In combination with the other ingredients, the mineral
filler and grinding aid greatly increase the mechanical strength,
and in particular the strength at young ages, of a cement matrix or
hydraulic binder.
[0024] The invention therefore relates to a method for conferring
on cement matrices or hydraulic binders such as concretes, mortars,
grouts or compositions based on calcium sulphate hemihydrate,
improved mechanical strength and notably improved mechanical
strength at young ages.
[0025] The aqueous suspension of ground mineral filler is prepared
by the addition of the grinding aid agent or agents to the mineral
filler when the mineral filler is ground. In other words, the
grinding aid agent or agents are not incorporated directly in the
cement matrix or hydraulic binder.
[0026] The grinding aid agents of the present invention are natural
or synthetic homopolymers and/or copolymers. A copolymer family is
described in French patent application No 9905665 of the Applicant,
(not published at the time of filing the present application).
However, the copolymers described therein have the function of
appreciably improving the workability of hydraulic binders. Thus,
one of skill in the art would not seek to use such a workability
agent as a grinding aid agent in the preparation of a suspension of
mineral filler used in the manufacture of cement matrices or
hydraulic binders. Likewise, it is not known in the art to prepare
a cement matrix by means of suspensions containing at least one
grinding aid agent.
[0027] Synthetic homopolymers or copolymers may be obtained by the
polymerisation of ethylenically unsaturated monomers, by
polycondensation, or by ring opening polymerisation.
[0028] The polymer or polymers obtained by polycondensation or by
ring opening polymerisation comprise polyaspartates and derivatives
thereof, or polylactates, as well as water-soluble polyesters,
polyamides or polylactones.
[0029] The ethylenically unsaturated monomer or monomers may be
selected from at least one of the ethylenically unsaturated anionic
monomers such as acrylic and/or methacrylic acid, itaconic,
crotonic or fumaric acid, maleic anhydride or isocrotonic,
aconitic, mesaconic, sinapic, undecylenic or angelic acid,
2-acrylamido-2-methyl-1-propane sulphonic acid,
2-methacrylamido-2-methyl-1-propane sulphonic acid,
3-methacrylamido-2-hydroxy-1-propane sulphonic acid, allylsulphonic
acid, methallylsulphonic acid, allyloxybenzene sulphonic acid,
methallyloxybenzene sulphonic acid,
2-hydroxy-3-(2-propenyloxy)propane sulphonic acid,
2-methyl-2-propene-1-sulphonic acid, ethylene sulphonic acid,
propene sulphonic acid, 2-methyl propene sulphonic acid, styrene
sulphonic acid, vinyl sulphonic acid, sodium methallylsulphonate,
sulphoethyl or sulphopropyl acrylate or methacrylate,
sulphomethacrylamide, sulphomethylmethacrylamide, alkylene glycol
acrylate or methacrylate phosphate or phosphonate or sulphate or
sulphonate, or vinyl phosphonate, or may be selected from at least
one non-ionic monomer such as acrylamide or methacrylamide or
derivatives thereof, C.sub.1 to C.sub.40 acrylic or methacrylic
acid alkyl-esters, vinyl acetate, vinylpyrrolidone, styrene or
.alpha.-methylstyrene.
[0030] The ethylenically unsaturated monomer or monomers may also
be selected from at least one alkoxy-, aryloxy-, alkylaryloxy-,
arylalkyloxy-polyalkylene glycol ethylenic urethane monomer,
sometimes referred to as special urethane monomer, or an alkoxy-,
aryloxy-, alkylaryloxy- or arylalkyloxy-polyalkylene glycol
ethylenic ester monomer such as an alkoxy-polyalkylene glycol
acrylate, methacrylate or hemimaleate or an oxyalkylated,
oxyarylated, oxyarylalkylated or oxyalkylarylated alkoxy-,
aryloxy-, alkylaryloxy- or arylalkyloxy-acrylate or methacrylate or
hemimaleate (the alkylene, arylene, alkylarylene or arylalkylene
oxide number being between 1 and 120), or an alkoxy-, aryloxy-,
alkylaryloxy- or arylalkyloxy-polyalkylene glycol ethylenic ether
monomer, and optionally one or more ethylenic monomers having at
least two polymerizable double bonds, referred to as a
cross-linking agents, chosen non-limitatively from the group
consisting of ethylene glycol dimethacrylate, divinylacetylene,
divinylbenzene, trimethylolpropanetriacrylate, allyl acrylate,
methylene-bis-acrylamide, methylene-bis-methacrylamide,
tetrallyloxyethane, the triallylcyanurates, allyl ethers obtained
from polyols such as pentaerythritol, sorbitol, sucrose or
others.
[0031] Preferably, the polymers of the present invention are either
homopolymers of acrylic or methacrylic acid or the copolymers
obtained by the radical copolymerization of at least one anionic
monomer with, optionally, at least one alkoxy-, aryloxy-,
alkylaryloxy- or arylalkyloxy-polyalkylene glycol ethylenic ester,
ether or urethane monomer and more particularly alkoxy-PEG
(polyethylene glycol) urethane, and possibly at least one non-ionic
monomer in the possible presence of alkoxy-, aryloxy-,
alkylaryloxy- or arylalkyloxy-polyalkylene glycol acrylate or
methacrylate or hemialeate and more particularly alkoxy-, aryloxy-,
alkylaryloxy- or arylalkyloxy-PEG acrylate or methacrylate or
hemialeate, the said PEG (polyethylene glycol) having a molecular
weight greater than 300, and in the optional presence of ethylenic
monomers having at least two polymerizable double bonds, also
referred to as cross-linking agents, chosen from the group
consisting of ethylene glycol dimethacrylate, divinylacetylene,
divinylbenzene, trimethylolpropanetriac- rylate, allyl acrylate,
methylene-bis-acrylamide, methylene-bis-methacryla- mide,
tetrallyloxyethane, the triallylcyanurates, allyl ethers obtained
from polyols such as pentaerythritol, sorbitol, sucrose or
others.
[0032] In some cases, the polymers of the present invention may be
homopolymers or copolymers of ethylenically unsaturated cationic
monomers such as methacrylamido propyl trimethyl ammonium chloride
or sulfate, trimethyl ammonium ethyl methacrylate chloride or
sulfate, as well as the corresponding acrylates or acrylamides
quaternized or not and/or the dimethyldiallyl ammonium
chloride.
[0033] The polymer used as a novel agent for improving strength at
young ages for cement matrices or hydraulic binders according to
the invention is prepared by the known processes of radical
polymerization in a solution, in an emulsion, in a suspension or by
precipitation of the aforementioned monomer or monomers, in the
presence of a catalytic system and known transfer agents, used in
appropriate quantities. The molecular weight of the polymer of the
present invention may be adjusted by known means such as, for
example, adjusting the reaction temperature, the amount of
catalyst, the presence or absence of transfer agents, or any other
means or combination of means known to one of skill in the polymer
synthesis art.
[0034] The polymerization catalyst system, which can vary in
quantity from 0.1% to 20% by weight with respect to the total
weight of monomers, is preferably selected from catalysts which are
water-soluble such as, for example, sodium, potassium or ammonium
persulphates, azo compounds, or peroxides or hydroperoxides such
as, for example, hydrogen peroxide. These catalysts may also be
combined with a known reducing compound such as sodium
metabisulphite, sodium hypophosphite, phosphorous acid,
hypophosphorous acid or metallic salts.
[0035] The chain transfer agent is preferably selected from
alkyl-mercaptans such as, for example, octanethiol, decanethiol,
n-dodecanethiol or t-dodecanethiol or from mercapto-propionic acid,
mercapto-succinic acid, thioglycolic acid or mercaptoethanol or
secondary alcohols, certain alkyl halides or the salts of
phosphorus acids with an oxidation number of less than 5, as well
as various other additives, known to one of skill in the polymer
art, as a chain limiter.
[0036] Throughout the present application, the abbreviations used
have the following meaning:
[0037] EGMAPO.sub.4=ethylene glycol methacrylate phosphate
[0038] EGMA=ethylene glycol methacrylate
[0039] PEG 350=polyethylene glycol with a molecular weight of
350
[0040] PEG 750=polyethylene glycol with a molecular weight of
750
[0041] and by analogy any number following the letters PEG
indicates the molecular weight of the said PEG.
[0042] EA=ethyl acrylate
[0043] Acryl=acrylamide
[0044] MAA=methacrylic acid
[0045] AA=acrylic acid
[0046] TEA=triethanolamine
[0047] TDI=toluene diisocyanate
[0048] IPDI=isophorone diisocyanate
[0049] Preferably, the following monomers are polymerized to
provide the polymer of the present invention:
[0050] a) at least one anionic monomer,
[0051] b) optionally at least one non-ionic monomer,
[0052] c) optionally at least one alkoxy-, aryloxy-, alkylaryloxy-
or arylalkyloxy-polyalkylene glycol ethylenic ester, ether or
urethane monomer, sometimes referred to as a special monomer,
[0053] d) optionally one of the ethylenic monomers having at least
two polymerizable double bonds and referred to as cross-linking
agents,
[0054] e) optionally at least one cationic monomer.
[0055] Even more preferably, the polymer of the present invention
is prepared from the following ethylenically unsaturated monomers
(% by weight):
[0056] a) 2% to 100% of at least one anionic monomer,
[0057] b) 0% to 50% of at least one non-ionic monomer,
[0058] c) 0% to 95% of at least one alkoxy-, aryloxy-,
alkylaryloxy- or arylalkyloxy-polyalkylene glycol ethylenic ester,
ether or urethane monomer, sometimes referred to as a special
urethane monomer,
[0059] d) 0% to 3% of one or more ethylenic monomers having at
least two polymerizable double bonds and referred to as
cross-linking agents,
[0060] e) 0% to 98% of at least one cationic monomer,
[0061] the total of monomers a), b), c), d) and e) being equal to
100%.
[0062] The preferred anionic monomer or monomers are selected from
acrylic acid, methacrylic acid, 2-acrylamido-2-methyl-1-propane
sulphonic acid, 2-methacrylamido-2-methyl-1-propane sulphonic acid,
3-methacrylamido-2-hydroxy-1-propane sulphonic acid, allylsulphonic
acid, methallylsulphonic acid, allyloxybenzene sulphonic acid,
methallyloxybenzene sulphonic acid,
2-hydroxy-3-(2-propenyloxy)propane sulphonic acid,
2-methyl-2-propene-1-sulphonic acid, ethylene sulphonic acid,
propene sulphonic acid, 2-methyl propene sulphonic acid, styrene
sulphonic acid, vinyl sulphonic acid, sodium methallylsulphonate,
sulphopropyl acrylate or methacrylate, sulphomethylacrylamide,
sulphomethylmethacrylamide, alkylene glycol acrylate or
methacrylate phosphate or phosphonate or sulphate or sulphonate,
itaconic acid, maleic anhydride, sodium methallylsulphonate and
more particularly chosen from amongst acrylic acid, methacrylic
acid, 2-acrylamido-2-methyl-1-propane sulphonic acid, ethylene
sulphonic acid, propene sulphonic acid, 2-methylsulphonic acid,
ethylene glycol methacrylate phosphate or ethylene glycol acrylate
phosphate.
[0063] The preferred non-ionic monomer or monomers are selected
from acrylamide or methacrylamide or derivatives thereof, the
C.sub.1 to C.sub.40 acrylic or methacrylic acid alkyl-esters, vinyl
acetate, vinylpyrrolidone, styrene or .alpha.-methylstyrene and
more particularly from amongst acrylamide or ethyl acrylate.
[0064] The alkoxy-, aryloxy-, alkylaryloxy- or
arylalkyloxy-polyalkylene glycol ester monomers are particularly
selected from alkoxy-, aryloxy-, alkylaryloxy- or
arylalkyloxy-polyalkylene glycol acrylates, methacrylates or
hemialeates or an oxyalkylated, oxyarylated, oxyarylalkylated or
oxylalkylarylated alkoxy-, aryloxy-, alkylaryloxy- or
arylalkyloxy-acrylate or methacrylate (the alkylene, arylene,
alkylarylene or arylalkylene oxide number being between 1 and
120).
[0065] The alkoxy-, aryloxy-, alkylaryloxy- or
arylalkyloxy-polyalkylene glycol urethane monomers are particularly
chosen from amongst alkoxy-polyalkylene glycols, reaction products
of alkoxy-polyalykylene glycol with a polymerizable unsaturated
isocyanate and more particularly from the reaction products of
methoxy-PEG with an acrylic, methacrylic, vinyl or allyl
isocyanate, wherein the PEG has a molecular weight greater than
300.
[0066] The ethylenically unsaturated cationic monomer or monomers
are particularly selected from methacrylamido propyl trimethyl
ammonium chloride or sulfate, trimethyl ammonium ethyl methacrylate
chloride or sulfate, as well as the corresponding acrylates or
acrylamides, either quaternized or not, and/or the dimethyldiallyl
ammonium chloride.
[0067] The polymer of the present invention may, subsequent to the
polymerization step, be fractionated by any fractionation means
known to one of skill in the polymer art.
[0068] The polymer of the present invention may be in a completely
acidic form, or partially or completely neutralized by one or more
neutralization agents having a monovalent function and possibly a
polyvalent function. For example, neutralization agents having a
monovalent function may be selected from the group consisting of
compounds containing alkaline cations, in particular sodium,
potassium, lithium, or ammonium, or the primary or secondary
aliphatic and/or cyclic amines, such as, for example,
ethanolamines, mono- or diethylamine or cyclohexylamine. The
neutralization agents having a polyvalent function may be selected
from the group consisting of compounds containing divalent
alkaline-earth cations, in particular magnesium, calcium, and zinc,
and trivalent cations, including, in particular, aluminum, or
compounds containing cations with a higher valency.
[0069] The mineral fillers of the present invention may be
selected, but are not limited to, natural calcium carbonate (chalk,
calcite, marble or other natural forms of calcium carbonate),
precipitated calcium carbonate, barium carbonate, limy rocks,
dolomite, talc, ground silica, silicas in general, fumed silica,
fumed titanium dioxide, diatomites, iron oxides, manganese oxides,
titanium dioxide, lime, kaolin, metakaolins, clays, mica, plasters,
fly ash, slag, calcium sulphate, zeolites, basalt, barium sulphate,
aluminum trihydroxide, or mixtures thereof.
[0070] The suspension of ground mineral filler of the present
invention may be prepared by grinding the mineral filler to be
refined in the following manner. First, an aqueous suspension of
the mineral matter to be refined is formed, containing the mineral
matter and the grinding aid agent or agents. Then the mineral
filler is ground with a grinding medium consisting of very fine
particles in the aqueous medium containing the grinding aid agent
or agents.
[0071] In a variant of the method of the present invention, it is
possible to prepare a suspension of a mixture of fillers by means
of co-grinding the fillers. That is, an aqueous suspension of the
mineral fillers to be refined is formed, then the mineral fillers
are co-ground. Another method of preparing a suspension of a
mixture of fillers according to the present invention comprises
grinding each of the fillers separately as described above, and
then mixing the suspensions of ground filler material together. The
dry weight of the suspension may vary from 10% by weight to 85% by
weight.
[0072] The ground mineral filler may be ground to the ultrafine
stage. In particular, the ground mineral filler may be a calcium
carbonate ground to the ultrafine stage, having a median diameter
of less than or equal to 20 .mu.m measured by means of a Cilas.TM.
850 or Sedigraph.TM. 5100 type granulometer (depending on the
granulometry of the filler to be measured).
[0073] The grinding aid agent is preferably selected from the
polymers, according to the present invention, obtained by radical
polymerisation and optionally at least one alkoxy-, aryloxy-,
alkylaryloxy- or arylalkyloxy-polyalkylene glycol ethylenic ester,
ether or urethane monomer and more particularly alkoxy-polyethylene
glycol urethane with at least one anionic monomer, and optionally
at least one non-ionic monomer in the possible presence of
ethylenic monomers having at least two polymerizable double bonds,
also referred to as cross-linking agents.
[0074] A second object of the present invention is a suspension of
filler or a mixture of fillers comprising a ground mineral filler
or fillers as described above, and at least one grinding aid agent
as defined above.
[0075] A third embodiment of the present invention is a cement
matrix or hydraulic binder, such as concrete, mortar, grout, or
compositions based on cement and/or calcium sulphate hemihydrate,
and more particularly hydraulic concrete, prepared by mixing the
cement matrix or hydraulic binder with the aqueous suspension of
the ground mineral filler or fillers and at least one grinding aid
agent of the present invention. Such cement matrices or hydraulic
binders have improved strength at young ages.
[0076] The cement matrices or hydraulic binders of the present
invention, containing the novel grinding aid agent which improves
the strength of the cement matrix or hydraulic binder at young
ages, may be used in construction, building, public works, civil
engineering, offshore works or as petroleum cements and
parapetroleum services.
[0077] The invention also covers all embodiments and all
applications which will be directly accessible to one of skill in
the art, from reading the present application, from his own
knowledge, and possibly from simple, routine tests.
[0078] Having generally described this invention, a further
understanding can be obtained by reference to certain specific
examples which are provided herein for purposes of illustration
only, and are not intended to be limiting unless otherwise
specified.
EXAMPLE 1
[0079] This example demonstrates an improvement in the mechanical
properties of a mortar provided by the use of a suspension of a
ground natural calcium carbonate.
[0080] In each of the tests of the example, the different
constituents of the standard mortar with a 450 kg/m.sup.3 cement
content were poured into a mortar mixer (EN 196-1) in the operating
position. The experiment was carried out on mortars whose rheology,
measured with a mortar workability meter defined by NF P 15-412,
was between 1 and 3 seconds. The quantities of constituents were
adjusted for each of the mortars of the different tests in order to
work at constant compactness. The composition was as follows:
[0081] 450 g of CEM I 42.5R CP2 cement from Gaurain in accordance
with NF P 15-301;
[0082] the quantity of ground calcium carbonate suspension to be
tested;
[0083] the necessary quantity of water;
[0084] a variable quantity, in grams, of standard Leucate sand (EN
196-1).
[0085] The sand was added according to EN 196-1 over 30 seconds and
after 30 seconds of slow stirring of the mixture of previously
added constituents. After 90 seconds of mixing, the mixer was
stopped in order to be able to scrape the walls of the mixer. Once
the scraping of the mortar adhering to the walls had ended, the
mixing was resumed for 1 minute at fast speed. This procedure
provided obtain a mixing cycle which lasted for 4 minutes, in
accordance with EN 196-1. At the end of the mixing, the test pieces
were formed and placed in a humid climatic chamber (EN 196-1) for
between 20 and 24 hours and then removed from the molds, weighed,
and placed in a storage vessel. This procedure was in accordance
with EN 196-1. At the required age, these test pieces were taken
from their storage chamber and then tested under bending and
compression in accordance with EN 196-1.
[0086] Test No 1
[0087] This test was of a reference mortar with a 450 kg/m.sup.3
cement content, without calcium carbonate, and having a
water/cement W/C ratio of 0.55.
[0088] Test No 2
[0089] This test was of a mortar of the prior art with a 450
kg/m.sup.3 cement content using 10% of a calcite powder sold under
the name Betocarb.TM. 2 (based on the dry weight of cement), having
a W/C ratio of 0.54.
[0090] Test No 3
[0091] This test was of a mortar of the prior art with a 450
kg/m.sup.3 cement content using 30% of a calcite powder sold under
the name Betocarb.TM. 2 (based on the dry weight of cement), having
a W/C ratio of 0.52.
[0092] Test No 4
[0093] This test was of a mortar according to the present
invention, with a 450 kg/m.sup.3 cement content and having a W/C
ratio of 0.55 and having 10% (dry weight, based on the dry weight
of cement), of an aqueous suspension of calcium carbonate having a
75% dry matter content, obtained by grinding a calcite to a median
diameter of 2 .mu.m (measured with the Sedigraph.TM. 5100) in the
presence of 0.75% (dry weight with respect to the dry weight of
calcium carbonate), of a copolymer comprising:
[0094] 15.0% by weight methacrylic acid;
[0095] -65.0% by weight methoxymethacrylate-PEG 750;
[0096] -20.0% by weight methoxymethacrylurethane-PEG 750.
[0097] Before the calcite was ground, the aqueous suspension of
calcium carbonate was prepared from calcite having a mean diameter
of around 50 .mu.m at a dry matter concentration of 75%. Thus,
0.75% by dry weight of the aforementioned grinding aid agent (based
on the dry weight of the calcium carbonate), was added into the
aqueous suspension of calcium carbonate. The suspension was then
circulated in a Dyno-Mill.TM. type grinder, having a fixed cylinder
and rotating impeller, whose grinding medium consisted of corundum
balls with a diameter within the range 0.6 mm to 1.0 mm. The total
volume occupied by the grinding medium was 1150 cm.sup.3, and the
weight of the grinding medium was 2900 g. The grinding chamber had
a volume of 1400 cm.sup.3, the circumferential speed of the grinder
was 10 m/s, and the calcium carbonate suspension was recycled at
the rate of 18 liters per hour. The outlet of the Dyno-Mill.TM.
grinder was provided with a separator having a 200 .mu.m mesh for
separating the suspension resulting from the grinding and the
grinding medium. The temperature during the grinding test was
maintained at approximately 60.degree. C. The calcium carbonate
suspension obtained by this process had the required granulometry
measured with a Sedigraph.TM. 5100 granulometer from
Micromeritics.
[0098] Test No 5
[0099] This test was of a mortar according to the present
invention, having a 450 kg/m.sup.3 cement content and with a W/C
ratio of 0.49 and using 30% (dry weight, based on the dry weight of
cement) of the same aqueous suspension of calcium carbonate as in
Test No 4. In addition, the procedure and the equipment used for
the grinding of the calcium carbonate were identical to those of
Test No 4.
[0100] The results of measuring the compression strength at 2 days,
7 days and 28 days for the different tests are set out in Table I
below.
1TABLE I REFERENCE PRIOR ART PRIOR ART INVENTION INVENTION TEST
N.degree. 1 2 3 4 5 Weight of cement in g 450 450 450 450 450
Weight of sand in g 1580 1534 1475 1516 1516 Weight of calcium
carbonate in g 0 45 135 45 135 Effective addition of water in g 248
242 234 248 220 Effective water/cement ratio 0.55 0.54 0.52 0.55
0.49 Workability in seconds 2.59 2.38 2.43 2.87 2.95 Compressive
strength in kN at 2 days 39.7 41.5 51.8 57.1 82.1 Compressive
strength in kN at 7 days 64.5 67.5 77.2 80.6 99.9 Compressive
strength in kN at 28 days 81.8 -- -- 96.2 115.2 Gain in strength in
% at 2 days 0 4.6 30.6 44 107 Gain in strength in % at 7 days 0 4.7
19.7 25 55 Gain in strength in % at 28 days 0 -- -- 13 35
[0101] The results of Table I, above, show that the compression
strength of mortars according to the present invention (i.e., the
strength at 2 days, 7 days and 28 days), are significantly improved
by the suspension of ground calcium carbonate (i.e., ultrafine
calcium carbonate), ground in the presence of the grinding aid
agent, compared to conventional mortars. In particular, the
strength of the mortars of the present invention at young ages
(i.e., the strength at 2 days and 7 days) is improved compared to
conventional mortars.
EXAMPLE 2
[0102] This example relates to the use of a suspension of ground
calcium carbonate having a different ultrafine granulometry.
[0103] A standard mortar having a 450 kg/m.sup.3 content was
prepared, having a suspension of ground calcium carbonate with a
median diameter of 1.55 .mu.m, measured with the Sedigraph.TM.
5100, using 0.7% of the grinding aid agent of Test No 4 and with
the same equipment and same procedure as Test No 4. The suspension
replaced volumes of water and sand so as to work at constant
compactness. In addition, the mortars have a rheology, measured on
a workability meter, between 1 to 3 seconds, according to the same
procedure as that of the previous example.
[0104] Test No 6
[0105] This test was of a reference mortar having a 450 kg/m.sup.3
cement content, without calcium carbonate, and with a water/cement
W/C ratio of 0.54.
[0106] Test No 7
[0107] This test was of a mortar according to the present
invention, having a 450 kg/m.sup.3 cement content, a W/C ratio of
0.49, and having 10% (dry weight, based on the dry weight of
cement) of the aqueous suspension of calcium carbonate described
above, with a median diameter of 1.55 .mu.m. The procedure and the
equipment used for grinding the calcium carbonate were identical to
those of Test No 4.
[0108] Test No 8
[0109] This test was of a mortar according to the present
invention, having a 450 kg/m.sup.3 cement content, a W/C ratio of
0.44, and having 30% (dry weight, based on the dry weight of
cement) of the aqueous suspension of calcium carbonate described
above, with a median diameter of 1.55 .mu.m. The procedure and the
equipment used for grinding the calcium carbonate were identical to
those of Test No 4.
[0110] The results of compression strength measurements at 2 days,
7 days and 28 days for the different tests are set out in Table II
below.
2TABLE II REFERENCE INVENTION INVENTION TEST N.degree. 6 7 8 Weight
of cement in g 450 450 450 Weight of sand in g 1580 1526 1510
Weight of calcium 0 45 135 carbonate in g Effective addition of 242
221 199 water in g Effective water/cement 0.54 0.49 0.44 ratio
Workability in seconds 2.79 2.11 2.74 Compressive strength 35.4
52.9 73.5 in kN at 2 days Compressive strength 60.1 77.4 91.5 in kN
at 7 days Compressive strength 76.7 89.9 104 in kN at 28 days Gain
in strength in % 0 49 107 at 2 days Gain in strength in % 0 29 52
at 7 days Gain in strength in % 0 17 35 at 28 days
[0111] The results of Table II, above, shows that the compression
strength (strength at 2 days, 7 days and 28 days) of a mortar
according to the present invention are significantly improved by a
suspension of ground calcium carbonate having an ultrafine
granulometry different from that of the previous example. In
particular, the strength at young ages (strength at 2 days and 7
days) is improved.
EXAMPLE 3
[0112] This example relates to the improvement in the mechanical
properties of a mortar according to the present invention, provided
by a suspension of natural calcium carbonate ground in the presence
of another type of grinding aid agent.
[0113] Thus, a mortar was produced using a suspension having 78% of
ground calcium carbonate (as dry matter) having a median diameter
of 1.0 .mu.m, measured with the Sedigraph.TM. 5100, containing
0.48% (dry weight, based on the dry weight of calcium carbonate) of
a polyacrylate completely neutralized by 70% sodium ions and 30%
calcium ions, using the same procedure and equipment as in Example
1.
[0114] Test No 9
[0115] This test was of a reference mortar having a 450 kg/m.sup.3
cement content, without calcium carbonate, and a water/cement W/C
ratio of 0.54.
[0116] Test No 10
[0117] This test was of a mortar according to the present
invention, having a 450 kg/m.sup.3 cement content, a W/C ratio of
0.54, and 10% (dry weight, based on the dry weight of cement) of
the aqueous suspension of calcium carbonate described above, with a
median diameter of 1.0 .mu.m. The procedure and equipment used for
grinding the calcium carbonate were identical to those of Test No
4.
[0118] Test No 11
[0119] This test was of a mortar according to the present
invention, having a 450 kg/m.sup.3 cement content, a W/C ratio of
0.54, and 30% (dry weight, based on the dry weight of cement) of
the aqueous suspension of calcium carbonate described above, with a
median diameter of 1.0 .mu.m. The procedure and equipment used for
grinding the calcium carbonate were identical to those of Test No
4.
[0120] The results of compression strength measurements carried out
at 2 days for the different tests are set forth in Table III,
below.
3TABLE III REFERENCE INVENTION INVENTION TEST N.degree. 9 10 11
Weight of cement in g 450 450 450 Weight of sand in g 1580 1535
1444 Weight of calcium 0 45 135 carbonate in g Effective addition
of 242 242 242 water in g Effective water/cement 0.54 0.54 0.54
ratio Compressive strength 39.7 48.6 57.4 in kN at 2 days Gain in
strength in % 0 22.4 44.6 at 2 days
[0121] The results of Table III, above, show that the compression
strength, at young ages (i.e., strength at 2 days) of a mortar
according to the present invention are significantly improved by a
suspension of calcium carbonate ground with another type of
grinding aid agent.
EXAMPLE 4
[0122] This example relates to the improvement in the mechanical
properties of a mortar provided by a suspension of different ground
fillers.
[0123] For each of the tests of this example, the different
constituents of a standard mortar with a 450 kg/m.sup.3 cement
content were poured into a mortar mixer (EN 196-1) in the operating
position. The quantities of constituents were adjusted for each of
the mortars of the different tests in order to work at constant
compactness. In addition, the experiment was carried out on mortars
whose rheology, measured with a mortar workability meter defined by
NF P 15-412, was between 1 and 3 seconds.
[0124] The composition of the standard mortar was as follows:
[0125] 450 g of CEM I 42.5R CP2 cement from Gaurain, according to
NF P 15-301;
[0126] the quantity of ground filler suspension to be tested
(except for the reference, where no suspension is added);
[0127] the necessary quantity of water;
[0128] a variable quantity, in grams, of standard Leucate sand (EN
196-1).
[0129] The sand was added according to EN 196-1 over 30 seconds,
and after 30 seconds of slow stirring of the mixture of the
previously added constituents. After 90 seconds of mixing, the
mixer was stopped in order to scrape the walls of the mixer. Once
the scraping of the mortar adhering to the walls had ended, the
mixing was resumed for 1 minute at fast speed. Thus, the mixing
cycle lasted for 4 minutes and was in accordance with EN 196-1.
[0130] At the end of the mixing, the test pieces were formed and
placed in a humid climatic chamber (EN 196-1) for between -20 and
24 hours, and then removed from the molds, weighed, and placed in a
storage vessel. This procedure was in accordance with EN 196-1. At
the required age, these test pieces were taken from their storage
chamber and then tested under bending and compression in accordance
with EN 196-1.
[0131] Test No 12
[0132] This test was of a reference mortar with a 450 kg/m.sup.3
cement content, without any filler, and having a water/cement W/C
ratio of 0.55.
[0133] Test No 13
[0134] This test was of a mortar according to the present
invention, having a 450 kg/m.sup.3 cement content, a W/C ratio of
0.59, and having 10% (dry weight, based on the dry weight of
cement) of an aqueous suspension of fumed silica with a 58.2% dry
matter content, obtained by grinding a fumed silica to a median
diameter equal to 3.03 .mu.m, measured with the Sedigraph.TM. 5100,
in the presence of 0.75% (dry weight based on the dry weight of
fumed silica) of a copolymer comprising:
[0135] 5.0% by weight methacrylamido propyl trimethyl ammonium
chloride, and
[0136] 95.0% by weight trimethyl ammonium ethyl methacrylate
chloride.
[0137] The device used for the grinding of the fumed silica was a
planetary grinder, MMS (Macchine Macina Smalto).
[0138] The fumed silica suspension thus obtained had the required
granulometry, measured by means of a Sedigraph.TM. 5100
granulometer from Micromeritics.
[0139] Test No 14
[0140] This test was of a mortar according to the present
invention, having a 450 kg/m.sup.3 cement content, a W/C ratio of
0.60, and 30% (dry weight, based on the dry weight of cement) of an
aqueous suspension of mixed calcium carbonate-talcum (75%-25% by
weight), having a 60% dry matter content, obtained by co-grinding a
mixture of calcium carbonate-talcum (75%-25% by weight) to a median
diameter equal to 0.74 .mu.m, measured with the Sedigraph.TM. 5100,
in the presence of 2.5% (dry weight, based on the dry weight of the
mixture of calcium carbonate-talcum) of a totally soda neutralized
copolymer comprising:
[0141] 95.0% by weight acrylic acid, and
[0142] 5.0% by weight tristyrylphenol methacrylate with 25 units of
ethylene oxide.
[0143] The procedure and equipment used for grinding the mixed
calcium carbonate-talcum are identical to those of test No 4,
above.
[0144] Test No 15
[0145] This was of a mortar according to the present invention,
having a 450 kg/m.sup.3 cement content, a W/C ratio of 0.48, and
30% (dry weight, based on the dry weight of cement) of an aqueous
suspension of chalk having a 59.9% dry matter content, obtained by
grinding a chalk suspension to a granulometry in which 75.2% of the
particles have a diameter less than 2 .mu.m, and 30.7% of the
particles have a diameter less than 1 .mu.m, measured with the
Sedigraph.TM. 5100, in the presence of 0.30% (dry weight based on
the dry weight of chalk) of a non-neutralized copolymer
comprising:
[0146] 14.1% by weight acrylic acid,
[0147] 3.4% by weight methacrylic acid, and
[0148] 82.5% by weight methoxy-PEG 2000 methacrylate.
[0149] The procedure and equipment used for grinding the chalk are
identical to those of test No 4, above.
[0150] Test No 16
[0151] This test was of a mortar according to the present
invention, having a 450 kg/m.sup.3 cement content, a W/C ratio of
0.52, and 30% (dry weight, based on the dry weight of cement) of an
aqueous suspension of precipitated calcium carbonate (PCC) having a
59.8% dry matter content, obtained by grinding a PCC suspension to
a granulometry such that 96.8% of the particles have a diameter of
less than 2 .mu.m, and 81.4% of the particles have a diameter less
than 1 .mu.m, measured with the Sedigraph.TM. 5100, in the presence
of 0.80% (dry weight based on the dry weight of PCC) of a 50 mol. %
triethanolamine neutralized copolymer comprising:
[0152] 42.0% by weight acrylic acid,
[0153] 42.0% by weight acrylamide,
[0154] 11.0% by weight ethylene glycol methacrylate condensed with
toluene diisocyanate and nonylphenol with 50 units of ethylene
oxide, and
[0155] 5.0% by weight ethyl acrylate.
[0156] The procedure and equipment used for grinding the PCC are
identical to those of test No 4.
[0157] Test No 17
[0158] This test was of a mortar according to the present
invention, having a 450 kg/m.sup.3 cement content, a W/C ratio of
0.52, and 30% (dry weight, based on the dry weight of cement) of an
aqueous suspension of dolomite having a 59.5% dry matter content,
obtained by grinding a dolomite suspension to a granulometry such
that 66.0% of the particles have a diameter less than 2 .mu.m and
42.3% of the particles have a diameter less than 1 .mu.m, measured
with the Sedigraph.TM. 5100, in the presence of 0.80% (dry weight
based on the dry weight of dolomite) of a 85 mol. % ammonia
neutralized copolymer comprising:
[0159] 76.0% by weight acrylic acid,
[0160] 15.0% by weight 2-acrylamido-2-methyl-1-propane sulfonic
acid, and
[0161] 9.0% by weight itaconic acid.
[0162] The procedure and equipment used for grinding the dolomite
are identical to those of test No 4.
[0163] Test No 18
[0164] This test was of a mortar according to the present
invention, having a 450 kg/m.sup.3 cement content, a W/C ratio of
0.50, and 30% (dry weight, based on the dry weight of cement) of an
aqueous suspension of silica having a 58.2% dry matter content,
obtained by grinding a silica suspension to a median diameter equal
to 2.51 .mu.m, measured with the Sedigraph.TM. 5100, in the
presence of 0.50% (dry weight based on the dry weight of silica) of
a totally lithium neutralized homopolymer of methacrylic acid.
[0165] The silica was ground in a one liter beaker containing 1 kg
of grinding beads with a diameter between 0.6 to 1 mm.
[0166] Test No 19
[0167] This test was of a mortar according to the present
invention, having a 450 kg/m.sup.3 cement content, a W/C ratio of
0.56, and 10% (dry weight, based on the dry weight of cement) of an
aqueous suspension of zeolite having a 30.6% dry matter content
obtained by grinding a zeolite suspension to a median diameter
equal to 1.67 .mu.m, measured with the Sedigraph.TM. 5100, in the
presence of 0.50% (dry weight based on the dry weight of zeolite)
of sodium polyaspartate.
[0168] The procedure and the equipment used for the grinding of the
zeolite are identical to those of test No 18.
[0169] Test No 20
[0170] This test was of a mortar according to the present
invention, having a 450 kg/m.sup.3 cement content, a W/C ratio of
0.68, and 30% (dry weight, based on the dry weight of cement) of an
aqueous suspension of zeolite having a 30.6% dry matter content
obtained by grinding a zeolite suspension to a median diameter
equal to 1.67 .mu.m, measured with the Sedigraph.TM. 5100, in the
presence of 0.50% (dry weight based on the dry weight of zeolite)
of sodium polyaspartate.
[0171] The procedure and the equipment used for grinding the
zeolite are identical to those of test No 18.
[0172] Test No 21
[0173] This test was of a mortar according to the present
invention, having a 450 kg/m.sup.3 cement content, a W/C ratio of
0.61, and 30% (dry weight, based on the dry weight of cement) of an
aqueous suspension of fly ash having a 39.2% dry matter content
obtained by grinding a fly ash suspension to a median diameter
equal to 5.27 .mu.m, measured with the Sedigraph.TM. 5100, in the
presence of 0.50% (dry weight based on the dry weight of fly ash)
of sodium polynaphthalene sulfonate.
[0174] The procedure and equipment used for grinding the fly ash
are identical to those of test No 18.
[0175] Test No 22
[0176] This test was of a mortar according to the present
invention, having a 450 kg/m.sup.3 cement content, a W/C ratio of
0.68, and 30% (dry weight, based on the dry weight of cement) of an
aqueous suspension of diatomite with a 42.2% dry matter content
obtained by grinding a diatomite suspension to a median diameter
equal to 4,78 .mu.m, measured with the Sedigraph.TM. 5100, in the
presence of 0.50% (dry weight, based on the dry weight of
diatomite) of sodium lignosulfonate. The procedure and equipment
used for grinding the diatomite are identical to those of test No
18.
[0177] Test No 23
[0178] This test was of a mortar according to the present
invention, having a 450 kg/m.sup.3 cement content, a W/C ratio of
0.57 and using 30% (dry weight, based on the dry weight of cement)
of an aqueous suspension of metakaolin with a 33,6% dry matter
content obtained by grinding a metakaolin suspension to a median
diameter equal to 3,46 .mu.m, measured with the Sedigraph.TM. 5100,
in the presence of 0.50% (dry weight, based on the dry weight of
metakaolin) of a mixture composed of 90% by weight of a sodium
polyacrylate and 10% by weight of a surfactant commercialized by
BASF under the trade name Pluronic.TM. PE 3100.
[0179] The procedure and equipment used for grinding the metakaolin
are identical to those of test No 18.
[0180] Test No 24
[0181] This test was of a mortar according to the present
invention, having a 450 kg/m.sup.3 cement content, a W/C ratio of
0.56 and using 30% (dry weight, based on the dry weight of cement)
of an aqueous suspension of slag with a 52,4% dry matter content
obtained by grinding a slag suspension to a median diameter equal
to 10,64 .mu.m, measured with the Sedigraph.TM. 5100, in the
presence of 0.50% (dry weight, based on the dry weight of slag) of
a totally soda neutralized copolymer comprising:
[0182] 54,5% by weight acrylic acid,
[0183] 34,6% by weight ethylene glycol methacrylate phosphate,
[0184] 10,8% by weight methylmethacrylate.
[0185] The procedure and equipment used for grinding the slag are
identical to those of test No 18.
[0186] For the different tests, the results of compression strength
measurements at 2 days, determined by the same method as described
in the previous examples, are set forth in Tables IVa and IVb,
below.
4TABLE IVa REFERENCE INVENTION INVENTION INVENTION INVENTION
INVENTION TEST N.degree. 12 13 14 15 16 17 Weight of cement in g
450 450 450 450 450 450 Weight of sand in g 1569 1487 1388 1436
1355 1485 Weight of mineral suspension 0 181 229 225 226 226 or
slurry in g Effective addition of water in g 248 267 269 214 233
234 Effective water/cement ratio 0.55 0.59 0.60 0.48 0.52 0.52
Compression strength in kN at 2 days 40 42.4 44.4 64 55.1 42.2 Gain
in strength in % at 2 days 0 6 11 60 38 5
[0187]
5TABLE IVb REFERENCE INVENTION INVENTION INVENTION INVENTION
INVENTION INVENTION TEST N.degree. 18 19 20 21 22 23 24 Weight of
cement in g 450 450 450 450 450 450 450 Weight of sand in g 1499
1494 1348 1406 1395 1490 1443 Weight of mineral suspension 232 147
441 344 319 134 258 or slurry in g Effective addition of water in g
225 252 306 275 246 257 252 Effective water/cement ratio 0.50 0.56
0.68 0.61 0.55 0.57 0.56 Compressive strength in kN at 51.3 56.0
48.0 48.4 53.6 45.2 48.4 2 days Gain in strength in % at 2 days 28
40 20 21 34 13 21
[0188] The results of Tables IVa and IVb, above, show that that the
compression strength, at young ages (i.e., strength at 2 days) of a
mortar according to the present invention are significantly
improved by a suspension or slurry of different ground fillers with
different types of grinding aid agent.
[0189] It is noted that one of skill in the art, who has read the
previous examples relating to mortars, could reliably predict that
the performance of concretes which are composed of the same
mortars, with an addition of gravel, would likewise have improved
properties. In the same manner, grouts (mortars without sand)
should show the same improvements.
[0190] The priority document of the present application, French
application 00 13661, filed Oct. 25, 2000, is incorporated herein
by reference.
* * * * *