The present invention relates to an admixture system for a hydraulic composition
and its use to improve the maintenance of the rheology of hydraulic compositions, and
more particularly hydraulic compositions of Portland cement5 .
Hydraulic compositions are compositions comprising a hydraulic binder, i.e., a
compound having the property of hydrating in the presence of water and whose hydration
makes it possible to obtain a solid having mechanical resistance characteristics. Hydraulic
10 compositions are for example concrete, screed or mortar.
It is known to add thinners (also called plasticizers or superplasticizers) that make
it possible to thin the hydraulic composition and thus decrease the water content of the
hydraulic binder paste in order in particular to obtain higher mechanical strengths. These
thinners also provide maintenance of the rheology, thus allowing stabilization of the
15 hydraulic binder composition over a longer length of time before it hardens and sets.
In particular known from FR 2,696,736 are polyalkoxylated phosphonates
described as providing exceptional water reduction and fluidity maintenance properties
over time (also called maintenance of rheology or maintenance of workability).
Also known from FR 2,893,038 are hydraulic binder compositions comprising high
20 alumina cement (comprising aluminates) and a retarder and a superplasticizer. The
addition of a retarder in such a system is not problematic, since the aluminates that are
present play an accelerator role therefore making it possible to obtain mechanical
strengths quickly.
In order to obtain improved properties, in particular in terms of water reduction and
25 maintenance of rheology, while retaining good viscosity properties and reducing costs,
admixtures have been proposed (FR 2,776,285, WO 2011/015781) comprising, in mixture,
at least one polyalkoxylated phosphonate and at least one second superplasticizer of the
polyalkoxylated polycarboxylate type.
30 There is still an interest in providing admixture systems making it possible to
improve the fluidity maintenance of a hydraulic composition, in particular while decreasing
the cost of such admixture use.
One aim of the present invention is therefore to provide an admixture system
35 making it possible to improve the maintenance of fluidity of a hydraulic composition, in
particular of Portland cement, in particular at a reduced cost.
3
Another aim of the present invention is to provide an admixture system making it
possible to improve the maintenance of fluidity in a hydraulic composition over a
significant length of time. In particular, one of the aims of the present invention is to
provide an admixture making it possible to have a fluidity maintenance over a duration
greater than or equal to 90 minutes, for example 240 to 300 minutes, in particular greate5 r
than 300 minutes. Another aim of the present invention is to propose a method making it
possible to limit the polyalkoxylated phosphonate assay in the admixture s while improving
maintenance of the fluidity of a hydraulic composition.
Still other aims will appear upon reading the following description of the invention.
10
These aims are met by the present invention, which proposes an admixture system
for a hydraulic composition, comprising:
- at least one polyalkoxylated phosphonate polymer;
- at least one polyalkoxylated polycarboxylate polymer; and
15 - at least one setting retarder of formula (I):
C1R’H(OH)[CH(OH)]nC(O)O1R (I)
wherein
R’ represents H;
R represents H, an ammonium, an amine group or an alkali or alkaline-earth metal;
20 or R and R’ are absent and C1 and O1 are connected by a covalent bond so as to
form a polyhydroxylactone cycle n represents an integer comprised between 2 and 6, for
example 4 or 5.
In one particular embodiment, the setting retarder is a setting retarder with formula
25 (I):
C1R’H(OH)[CH(OH)]nC(O)O1R (I)
wherein
R’ represents H;
R represents H, an ammonium, an amine group or an alkali or alkaline-earth metal
30 n represents an integer comprised between 2 and 6, for example 4 or 5.
Preferably in this embodiment, n represents 4 or 5, preferably 4.
In another embodiment, the setting retarder is a compound of formula (Ia):
4
CH
OH
CH
O OH
O
n
(Ia)
wherein n represents an integer comprised between 2 and 6, for example 4 or 5.
In the context of the present invention, a hydraulic composition refers to a
5 composition comprising a hydraulic binder. For example, a hydraulic composition refers to
a composition comprising a hydraulic binder, optionally an aggregate, a mineral addition,
water, an additive (such as a superplasticizer, an anti-foaming additive, an air-entraining
additive, a plasticizer or a thinner).
In the context of the present invention, the hydraulic compositions are for example
10 concrete, mortar or screed compositions.
"Aggregate" refers to a set of mineral grains with an average diameter comprised
between 0 and 125 mm. Depending on their diameter, the aggregates are classified in one
of the six following families: fillers, fine sands, sands, gravels, crushed stone and ballast
(standard XP P 18-545). The most widely used aggregates are the following:
15 - fillers, which have a diameter smaller than 2 mm and for which at least 85% of the
aggregates have a diameter smaller than 1.25 mm and at least 70% of the aggregates
have a diameter smaller than 0.063 mm,
- sands, with a diameter comprised between 0 and 4 mm (standard 13-242, the
diameter being able to reach up to 6 mm),
20 - gravels, with a diameter greater than 6.3 mm,
- crushed rocks, with a diameter comprised between 2 mm and 63 mm.
Sands are therefore comprised in the definition of aggregate according to the invention.
The fillers may in particular be of limestone or dolomitic origin.
"Hydraulic binder" refers to any compound having the property of hydrating in the
25 presence of water and whose hydration makes it possible to obtain a solid having
mechanical characteristics, in particular a cement such as Portland cement, pozzolanic
cement or an anhydrous or semi-hydrated calcium sulfate. The hydraulic binder may be a
cement according to standard EN 197-1 (2001), and in particular a Portland cement,
mineral additions, in particular slag, or a cement comprising mineral additions.
30 "Cement", and in particular "Portland cement", refers to a cement according to
standard EN 197-1 (2001), and in particular a cement of type CEM I, CEM Il, CEM III,
5
CEM IV or CEM V according to Cement standard NF EN 197-1 (2001). The cement, and
in particular Portland cement as defined in standard EN 197-1 (2001), may comprise
mineral additions.
"Mineral additions" refers to slags (as defined in the Cement standard NF EN 197-
1(2001) paragraph 5.2.2), slag from steel mills, pozzolanic materials (as defined 5 in
Cement standard NF EN 197-1(2001) paragraph 5.2.3), fly ash (as defined in the Cement
standard NF EN 197-1(2001) paragraph 5.2.4), burnt shales (as defined in the Cement
standard NF EN 197-1(2001) paragraph 5.2.5), limestones (as defined in the Cement
standard NF EN 197-1(2001) paragraph 5.2.6) or silica fumes (as defined in the Cement
10 standard NF EN 197-1(2001) paragraph 5.2.7), or mixtures thereof. Other additions, not
currently recognized by Cement standard NF EN 197-1(2001), can also be used. These in
particular involve metakaolins, such as type A metakaolins according to standard NF P
18-513 (August 2012), and siliceous additions, such as siliceous additions of Qz
mineralogy according to standard 18-509 (September 2012).
15
Preferably, the hydraulic compositions according to the invention are Portland
cement compositions as defined in standard EN 197-1 (2001). The Portland cement
compositions according to the invention may further comprise mineral additions as defined
above, in particular with the exception of aluminate.
20
The invention more particularly covers the use of said admixture system as a thinner for
hydraulic compositions of Portland cement, in particular to improve the maintenance of
fluidity of these hydraulic compositions over time, in particular in the long term, and in
particular over durations greater than or equal to 90 minutes, preferably between 240 and
25 300 minutes, in particular greater than 300 minutes.
In the context of the present invention, the polyalkoxylated polycarboxylate
polymer is preferably a comb polymer comprising a skeleton and side chains including the
following patterns (III) and (IV):
30
*—R1—(C(O))m—R2-(Alk-O)n—R3 (III)
where * designates the attachment point to the skeleton of the comb polymer, R1
is a chemical bond or alkylene group of 1 to 8 carbon atoms, m is equal to 0 or 1, R2
35 designate an oxygen atom or an amine group, Alk designates alkylene with 2 to 4 carbon
atoms, linear or branched, n designates an integer comprised between 3 and 500, a same
6
polymer being able to bear grafts with different lengths, and R3 designates a hydrogen
atom or a hydrocarbon group such as an alkyl including 1 to 25 carbon atoms.
*—R4 (IV)
where R4 comprises an acid and/or dissociated anionic function.
5
A superplasticizer of the comb polymer type also refers to the superplasticizers
obtained by mixing different polymers including side chains of type (I) and (II).
In the context of the present invention, the polyalkoxylated phosphonate polymer is
preferably a polyalkoxylated phosphonate with formula (V) or one of its 10 salts, alone or in a
mixture:
wherein:
R5 is a hydrogen atom or monovalent hydrocarbon group including from 1 to 18
15 carbon atoms and optionally one or more heteroatoms;
the Ri are similar to or different from one another and represent an alkylene such
as ethylene, propylene, butylene, amylene, octylene or cyclohexene, or an arylene such
as styrene or methylstyrene, the Ri optionally containing one or more heteroatoms;
Q is a hydrocarbon group including 2 to 18 carbon atoms and optionally one or
20 more heteroatoms;
A is an alkylidene group including 1 to 5 carbon atoms;
the Rj are similar to or different from one another and can be chosen from among:
- the A-PO3H2 group, A having the aforementioned meaning,
- the alkyl group including 1 to 18 carbon atoms and able to bear [R5-O(Ri-O)m]
25 groups, R5 and Ri having the aforementioned meanings,
“m” is a number greater than or equal to 0,
"r" is the number of groups [R5-O(Ri-O)m] carried by the set of Rj,
"q" is the number of groups [R5-O(RiO)m] carried by Q, the sum
"r+q" is comprised between 1 and 10,
30 “y” is an integer comprised between 1 and 3,
Q, N and the Rj can form one or more cycles together, this or these cycles
further being able to contain one or more other heteroatoms.
7
Particularly preferably, the polyalkoxylated phosphonate is made up of a
hydrosoluble or hydrodispersible organic compound including at least one amino-di-
(alkylene phosphonic) group and at least one polyoxyalklyated chain or at least one of its
salt5 s.
Preferably, the polyalkoxylated phosphonate is a compound with formula (V) in
which:
R5 is a hydrogen atom or a monovalent hydrocarbon group, saturated or not,
including 1 to 8 carbon atoms and optionally one or more heteroatoms;
10 the Ri represent ethylene or propylene or a mixture of ethylene or propylene,
preferably 60 to 100% of the Ri are ethylene groups;
Q is a hydrocarbon group including 2 to 8 carbon atoms and, optionally, one or
more heteroatoms;
A is the methylene group;
15 each of the Rj represents the CH2-PO3H2 group;
m is an integer comprised between 10 and 250;
q is in integer greater than or equal to 1 or 2;
y is in integer equal to 1 or 2.
20 In particular, the polyalkoxylated phosphonate can be a polyalkoxylated
phosphonate of formula (V) in which R5 is a methyl group, the Ri are ethylene and
propylene groups, m being comprised between 30 and 50, r+q is equal to 1, Q is an
ethylene group, A is a methylene group, y is equal to 1 and Rj corresponds to the CH2-
PO3H2 group.
25
Preferably, the retarder is chosen from among gluconic acid and its salts, in
particular alkali salts, for example sodium, lithium or potassium, ammonium or amine
group.
30 The system according to the invention preferably comprises, by dry weight relative
to the total binder weight, 0.03 to 1% of polyalkoxylated phosphonate, 0.03 to 1% of
polyalkoxylated polycarboxylate and 0.03 to 0.3% of retarder of formula (I).
In the context of the present invention, total binder refers to the sum of the masses of
cement, preferably Portland cement, mineral additions and fillers. The fillers may in
35 particular be of limestone, siliceous or dolomitic origin.
8
The system according to the invention preferably comprises, in dry weight relative
to the total binder weight, preferably relative to the weight of Portland cement and any
mineral additions as defined above, 0.09 to 0.65%, preferably 0.09 to 0.35% of
polyalkoxylated phosphonate, 0.09 to 0.35% of polyalkoxylated polycarboxylate and 0.06
to 0.24% of retarder of formula (5 I).
Particularly advantageously, the inventors have shown that the particular choice of
a retarder of formula (I), in particular in the aforementioned proportions, added to an
admixture system comprising at least one polyalkoxylated polycarboxylate and at least
10 one polyalkoxylated phosphonate makes it possible to improve the maintenance of fluidity
(maintenance of rheology), in particular over the long term, in particular over durations
greater than or equal to 90 minutes, preferably between 240 and 300 minutes, in particular
greater than 300 minutes, relative to other retarders known by those skilled in the art.
Indeed, as shown by the examples of the present invention, retarders of formula (I)
15 compared to the other retarders known by those skilled in the art advantageously make it
possible, combined with a polyalkoxylated phosphonate and a polyalkoxylated
polycarboxylate, to obtain a hydraulic composition, preferably Portland cement, with
maintenance of rheology in particular over durations greater than or equal to 90 minutes,
preferably between 240 and 300 minutes, preferably greater than 300 minutes.
20 Particularly advantageously, the inventors have shown that replacing part of the
polyalkoxylated polycarboxylate or part of the polyalkoxylated phosphonate, in particular
part of the polyalkoxylated phosphonate, with an equivalent quantity of retarder of formula
(I), in particular in the aforementioned proportions, in a system comprising at least one
polyalkoxylated polycarboxylate and at least one polyalkoxylated phosphonate makes it
25 possible to improve the maintenance of fluidity (maintenance of rheology or maintenance
of workability) in particular over the long term, in particular over durations greater than or
equal to 90 minutes, preferably between 240 and 300 minutes, in particular greater than
300 minutes.
The admixture system of the present invention may further comprise additives of
30 the air-entraining additive type and/or anti-foaming additives.
A system made up of the three components described above, excluding other
additives, or at least additives that may affect workability and early resistance, for example
excluding aluminate, is particularly preferred.
35
9
The invention also relates to a method for preparing the admixture system
according to the invention comprising the step of mixing at least one polyalkoxylated
polycarboxylate, at least one polyalkoxylated phosphonate and a retarder of formula (I).
The invention also relates to a method for preparing hydraulic composit5 ions,
preferably Portland cement, in particular concrete, mortar or screed, comprising the step
of adding, in appropriate quantities, respectively:
(a) a polyalkoxylated polycarboxylate;
(b) a polyalkoxylated phosphonate; and
10 (c) a retarder of formula (I),
simultaneously or successively, preferably simultaneously, to a hydraulic binder
paste, preferably Portland cement, during mixing. The admixture system according to the
invention is consequently added in the mixing water.
The polyalkoxylated polycarboxylate, the polyalkoxylated phosphonate and the
15 retarder of formula (I) are as defined above.
The invention also relates to a method for preparing hydraulic compositions,
preferably Portland cement, in particular concrete, mortar or screed, comprising the step
of adding, in appropriate quantities, respectively:
20 (a) a polyalkoxylated polycarboxylate;
(b) a polyalkoxylated phosphonate; and
(c) a retarder of formula (I),
simultaneously or successively, to the solid components of the hydraulic
composition, preferably Portland cement, in particular to the hydraulic binder, preferably
25 Portland cement, or to the sand.
The polyalkoxylated polycarboxylate, the polyalkoxylated phosphonate and the
retarder of formula (I) are as defined above.
The invention also relates to a method for preparing hydraulic compositions,
30 preferably Portland cement, comprising the step of mixing:
- an admixture system according to the invention;
- at least one hydraulic binder, preferably Portland cement;
- sand;
- optionally at least one aggregate;
35 - water,
10
the components of the hydraulic composition being added in any order and the
components of the admixture system being added simultaneously or successively with
respect to the water, to the hydraulic binder, preferably Portland cement, the sand and/or
the aggregate making up the hydraulic composition.
5
The invention also relates to a hydraulic composition, preferably Portland cement,
comprising an admixture system according to the invention.
The invention also relates to the use of the admixture system described for the
preparation of hydraulic compositions, preferably Portland 10 land cement.
Advantageously, the admixture system is added to the hydraulic composition
during mixing, preferably by adding to the mixing water. Alternatively, the admixture can
be added to the solid components of the hydraulic composition, in particular to the
hydraulic binder, preferably Portland cement, and/or to the sand.
15 Of course, other typical additives known by those skilled in the art can also be
added to the concrete composition directly or by means of a component of the hydraulic
composition (for example, by means of the admixture system according to the invention).
Examples include air-entraining agents and anti-foaming agents.
20 The present invention also relates to the use of the admixture system as a thinner
for hydraulic compositions, in particular Portland cement, in particular to improve the
maintenance of fluidity (or maintenance of workability) of said hydraulic compositions over
time, in particular in the long term, in particular over durations greater than or equal to 90
minutes, preferably between 240 and 300 minutes, in particular greater than 300 minutes.
25 Preferably, the invention relates to the use of an admixture system comprising, by
dry weight relative to the total binder weight, in particular relative to the weight of Portland
cement and any mineral additions, 0.03 to 1% of polyalkoxylated phosphonate, 0.03 to 1%
of polyalkoxylated polycarboxylate and 0.03 to 0.3% of retarder of formula (I) as thinner for
hydraulic compositions, in particular to improve the maintenance of fluidity (or
30 maintenance of workability) of hydraulic compositions over time, in particular in the long
term, in particular over durations greater than or equal to 90 minutes, preferably between
240 and 300 minutes, in particular greater than 300 minutes.
Preferably, the invention relates to the use of an admixture system comprising, by
dry weight relative to the total binder weight, 0.09 to 0,35% of polyalkoxylated
35 phosphonate, 0.09 to 0,35% of polyalkoxylated polycarboxylate and 0.06 to 0.24% of
retarder of formula (I) as thinner for hydraulic compositions, in particular to improve the
11
maintenance of fluidity (or maintenance of workability) of hydraulic compositions over
time, in particular in the long term, in particular over durations greater than or equal to 90
minutes, preferably between 240 and 300 minutes, in particular greater than 300 minutes.
The present invention also relates to a method for improving the maintenance o5 f
fluidity (or maintenance of workability) over time of a hydraulic composition, in particular
Portland cement, comprising a step consisting of placing said hydraulic composition in
contact with an admixture system according to the invention.
10 The present application will now be described using non-limiting examples.
The invention is illustrated in the following examples of preparations of hydraulic
binder compositions of the mortar or concrete type.
15 The characterizations of the obtained hydraulic compositions (in particular
maintenance of fluidity) are done using the Abrams cone by measuring the slump test for
concretes and by measuring mortar spreading using the MCE (Mortar Concrete
Equivalent) cone of 700 cm³, according to the CALIBE method described in "Results of
Recommendations of the CALIBE National Project”, 2004 Edition: Presse de l'école
20 nationale des Ponts et chaussées, Chapter 5, page 111: "La méthode MBE".
The determination according to the Abrams cone method is done according to
standard EN 12350-2 from 2012. The test consists of using freshly prepared concrete to
fill a bottomless mold with a frustoconical shape with the following dimensions:
25 diameter of the circle of the base greater than 100 +/- 0.5 mm
diameter of the circle of the base less than 200 +/- 0.5 mm
height 300 +/- 0.5 mm
The cone is raised vertically. The spreading is measured between 5 and 300
minutes according to four diameters at 45° with a sliding caliper. The result of the
30 spreading measurement is the average of the four values at +/- 10 mm. The tests are
done at 20°C.
The admixture system is added to the hydraulic composition by the mixing water.
35 Example 1
12
The performance in terms of maintenance of rheology of an admixture system
according to the invention was compared to that of an admixture system not comprising a
retarder or comprising a different retarder from those of formula (I) for a concrete
composition with the following formulation (the cement used is CEM I 52.5 N PMES CE
CP2 NF Le HAVRE de LAFARGE) brought to 1m3 5 :
Portland cement 330 kg
Filler Millisil C10 60 kg
Condensil DM silica fume 30 kg
Sand 0/1 R SEL SOIL 120 kg
Sand 0/4 R SABCO 685 kg
Gravel 4/10 C Montebourg 200 kg
Gravel 10/20 C Montebourg 785 kg
Total water 173 kg
Effective water 160 kg
The mortar concrete equivalent was calculated based on this composition.
The concentrations of the admixtures are respectively expressed in percentage of
dry extract relative to the total quantity of binder (cement + filler and/or cement additions).
10
The polyalkoxylated phosphonate (A) is the CHRYSO®Fluid Optima 100 marketed
by the company CHRYSO.
The polyalkoxylated polycarboxylate (B) is a mixture of polyalkoxylated
polycarboxylate marketed by the company CHRYSO.
15 The retarder (C) according to the invention is sodium gluconate.
The obtained results are shown in table 1 below:
CHR: polyol-type additive
CE: potassium phosphate-type additive
20 % loss: (value of the spreading or slump at 300 minutes - value of the spreading or slump
at the initial T5) / value of the spreading or slump at initial T5
M=Mortar
C=Concrete
13
5
min
30
min
60
min
90
min
120
min
150
min
180
min
210
min
240
min
270
min
300
min
Test A B C CHR CE
Total
admixture (%) Spreading (mm)
%
loss
1 M 0.65 0.35 1 390 390 390 390 400 400 380 355 335 325 300 23.1
2 M 0.59 0.35 0.94 375 370 365 350 335 290 280 265 245 215 195 48
3 M 0.53 0.35 0.88 360 355 355 325 300 260 250 235 215 200 180 50
4 M 0.35 0.35 0.2 0.9 350 380 380 380 390 400 375 365 355 335 315 10
5 M 0.35 0.35 0.16 0.86 305 315 315 310 300 280 270 260 255 250 245 19.7
6 M 0.35 0.35 0.15 0.85 300 315 305 295 270 270 250 235 220 205 195 35
7 M 0.35 0.35 0.25 0.95 240 250 240 230 200 190 185 170 160 150 140 41.7
Slump (cm)
8 C 0.62 0.35 0.97 23 23 23 23 22 21 20 18 16 14 13 43.5
9 C 0.35 0.35 0.24 0.94 16 21.5 21 20 18 17 18 18 15 15 15 9.4
Table 1
14
These results show the impact of a retarder with formula (I) combined with a
polyalkoxylated polycarboxylate and a polyalkoxylated phosphonate on the maintenance
of rheology.
The comparison of tests 1 to 3 shows the decrease in the polyalkoxylated
phosphonate assay causes a drop in the maintenance of rheology5 .
On the contrary, the comparison of tests 3 and 4 and tests 8 and 9 shows that a
partial substitution of phosphonate by gluconate for an equivalent total additive assay
allows a significant improvement in the maintenance of rheology. The spreading loss %
goes from 50 to 10% and from 43.5 to 9.4%.
10 The results also show that the increase of the gluconate assay results in an
improvement in the plasticity and maintenance. The loss % goes from 19 to 10%
(comparison of tests 4 and 5).
The results of the maintenance of rheology are lower performing with CHR relative
to the gluconate (comparison of tests 5 and 6), which reflects the specificity of the
15 gluconate combined with a polyalkoxylated polycarboxylate and a polyalkoxylated
phosphonate on the rheology maintenance properties.
The rheology maintenance results are lower performing with CE relative to
gluconate (comparison of tests 4 and 7), which reflects the specificity of the gluconate
combined with a polyalkoxylated polycarboxylate and a polyalkoxylated phosphonate on
20 the rheology maintenance properties.
Example 2
The performance in terms of maintenance of rheology of an admixture system
according to the invention was compared to that of an admixture system not comprising a
25 retarder or comprising a different retarder from those of formula (I) for a concrete
composition with the following formulation (the cement used is CEM II/A-LL 42,5 R
Couvrot de Calcia) brought to 1m3 :
Cement 280 kg
Sand 0/4 R Rosnay 970 kg
Gravel 6.3/20 825 kg
Effective water 160 kg
15
The mortar concrete equivalent was calculated based on the following composition:
Cement 320 kg
Sand 0/4 R Rosnay 885 kg
Gravel 6.3/20 995 kg
Effective water 158 kg
The obtained results are shown in table 5 ble 2 below:
5
min
30
min
60
min
90
min
Test A C C
Total dry
admixture
(%)
Spreading (mm) %
loss
10 M 0.24 0.24 0.48 310 300 290 270 12.9
11 M 0.23 0.23 0.06 0.49 310 300 300 300 3.2
Slump (cm)
12 C 0.18 0.18 0.36 17 15 15 4 76.5
13 C 0.16 0.16 0.06 0.38 18 19 17 17 5.6
Table 2
% loss: (value of the spreading or slump at 90 minutes - value of the spreading or
slump at the initial T5) / value of the spreading or slump at initial T5
10
The results show (comparison of tests 10 and 11 and tests 12 and 13) that an
addition of gluconate with very low assay allows a significant improvement in the
maintenance of rheology.

I/We Claim:
1.- A use of an additive system, comprising
- at least one polyalkoxylated phosphonate polymer;
- at least one polyalkoxylated polycarboxylate polymer; 5 and
- at least one setting retarder of formula (I):
C1R’H(OH)[CH(OH)]nC(O)O1R (I)
wherein
R’ represents H;
10 R represents H, an ammonium, an amine group or an alkali or alkaline-earth metal;
or R and R’ are missing and C1 and O1 are connected by a covalent bond so as to
form a polyhydroxylactone cycle n represents an integer comprised between 2 and 6, for
example 4 or 5,
as thinner for hydraulic compositions made up of Portland cement, optionally mixed with
15 mineral additions chosen from among slags, pozzolanic materials, fly ash, burnt shales,
limestones, silica fumes, metakaolins, siliceous additions, or mixtures thereof, in particular
to improve the maintenance of fluidity of hydraulic compositions over time, in particular in
the long term, and in particular over durations greater than or equal to 90 minutes,
preferably between 240 and 300 minutes, in particular greater than 300 minutes.
20
2.- The use according to claim 1, wherein the retarder is a retarder of formula (I) wherein
R’ represents H and R represents H, an ammonium, an amine group or an alkali or
alkaline-earth metal and n is equal to 4 or 5.
25 3.- The use according to claim 1 or 2, wherein the retarder is chosen from among gluconic
acid and its salts, in particular alkali salts, for example sodium, lithium or potassium,
ammonium or amine group.
4.- The use according to one of claims 1 to 3, wherein the additive system comprises, by
30 dry weight relative to the total binder weight, 0.03 to 1% of polyalkoxylated phosphonate,
0.03 to 1% of polyalkoxylated polycarboxylate and 0.03 to 0.3% of retarder of formula (I).
5.- The use according to one of claims 1 to 4, wherein the additive system comprises, by
dry weight relative to the total binder weight, preferably Portland cement, 0.09 to 0.65% of
35 polyalkoxylated phosphonate, 0.09 to 0.35% of polyalkoxylated polycarboxylate and 0.06
to 0.24% of retarder of formula (I).
ARTICLE 19 AMENDED CLAIMS
17
6.- The use according to one of claims 1 to 4, wherein the additive system comprises, by
dry weight relative to the total binder weight, preferably Portland cement, 0.09 to 0.35% of
polyalkoxylated phosphonate, 0.09 to 0.35% of polyalkoxylated polycarboxylate and 0.06
to 0.24% of retarder of formula (I).
5
7.- The use according to one of claims 1 to 6, wherein the polyalkoxylated polycarboxylate
polymer is preferably a comb polymer including a skeleton and side chains having the
following patterns (III) and (IV):
*—R1—(C(O))m—R2-(Alk-O)n—R3 10 (III)
where * designates the attachment point to the skeleton of the comb polymer, R1
is a chemical bond or alkylene group of 1 to 8 carbon atoms, m is equal to 0 or 1, R2
designates an oxygen atom or an amine group, Alk designates alkylene with 2 to 4 carbon
15 atoms, linear or branched, n designates an integer comprised between 3 and 500, a same
polymer being able to bear grafts with different lengths, and R3 designates a hydrogen
atom or a hydrocarbon group such as an alkyl including 1 to 25 carbon atoms
*—R4 (IV)
where R4 comprises an acid and/or dissociated anionic function.
20
8.- The use according to one of claims 1 to 7, wherein the polyalkoxylated phosphonate
polymer is preferably a polyalkoxylated phosphonate of formula (V) or one of its salts,
alone or in a mixture:
25 wherein:
R5 is a hydrogen atom or monovalent hydrocarbon group including from 1 to 18 carbon
atoms and optionally one or more heteroatoms;
the Ri are similar to or different from one another and represent an alkylene such as
ethylene, propylene, butylene, amylene, octylene or cyclohexene, or an arylene such as
30 styrene or methylstyrene, the Ri optionally containing one or more heteroatoms;
Q is a hydrocarbon group including 2 to 18 carbon atoms and optionally one or more
heteroatoms;
18
A is an alkylidene group including 1 to 5 carbon atoms;
the Rj are similar to or different from one another and can be chosen from among:
- the A-PO3H2 group, A having the aforementioned meaning,
- the alkyl group including 1 to 18 carbon atoms and able to bear [R5-O(Ri-O)m]
groups, R5 and Ri having the aforementioned meaning5 s,
“m” is a number greater than or equal to 0,
"r" is the number of groups [R5-O(Ri-O)m] carried by the set of Rj,
"q" is the number of groups [R5-O(RiO)m] carried by Q, the sum
"r+q" is comprised between 1 and 10,
10 “y” is an integer comprised between 1 and 3,
Q, N and the Rj can form one or more cycles together, this or these cycles further being
able to contain one or more other heteroatoms.
9.- The use according to claim 8, wherein:
15 R5 is a hydrogen atom or a monovalent hydrocarbon group, saturated or not, including 1
to 8 carbon atoms and optionally one or more heteroatoms;
the Ri represent ethylene or propylene or a mixture of ethylene or propylene, preferably
60 to 100% of the Ri are ethylene groups;
Q is a hydrocarbon group including 2 to 8 carbon atoms and, optionally, one or more
20 heteroatoms;
A is the methylene group;
each of the Rj represents the CH2-PO3H2 group;
m is an integer comprised between 10 and 250;
q is in integer greater than or equal to 1 or 2;
25 y is in integer equal to 1 or 2.
10.- The use according to claim 8, wherein R5 is a methyl group, the Ri are ethylene and
propylene groups, m being comprised between 30 and 50, r+q is equal to 1, Q is an
ethylene group, A is a methylene group, y is equal to 1 and Rj corresponds to the CH2-
30 PO3H2 group.
11.- The use according to one of claims 1 to 10, further comprising additives of the airentraining
additive type and/or anti-foaming additives.
35 12.- A method for preparing hydraulic compositions of Portland cement, comprising the
step of adding, in appropriate quantities, respectively:
19
(a) a polyalkoxylated polycarboxylate according to one of claims 1 to 11;
(b) a polyalkoxylated phosphonate according to one of claims 1 to 11; and
(c) a retarder of formula (I) according to one of claims 1 to 11,
simultaneously or successively, to a Portland cement paste during mixing.
5
13.- A method for preparing hydraulic compositions of Portland cement, comprising the
step of adding, in appropriate quantities, respectively:
(a) a polyalkoxylated polycarboxylate according to one of claims 1 to 11;
(b) a polyalkoxylated phosphonate according to one of claims 1 to 11; and
(c) a retarder of formula (I) according to one of claims 1 10 to 11,
simultaneously or successively, to the solid components of the hydraulic composition of
Portland cement.
14.- A method for preparing a hydraulic composition of Portland cement, comprising the
15 step of mixing:
- an additive system according to one of claims 1 to 11;
- at least one Portland cement;
- sand;
- optionally at least one aggregate;
20 - water,
the components of the hydraulic composition being added in any order and the
components of the additive system being added simultaneously or successively with
respect to the water, the Portland cement, the sand and/or the aggregate making up the
hydraulic composition.
25
15.- A hydraulic composition made up of Portland cement, optionally mixed with mineral
additions chosen from among slags, pozzolanic materials, fly ash, burnt shales,
limestones, silica fumes, metakaolins, siliceous additions, or mixtures thereof, comprising
an additive system according to one of claims 1 to 11.