Additive for hydraulically setting compositions

Patent metadata

Field	Value
Publication number	US-9796628-B2
Application number	US-201515111213-A
Country	US
Kind code	B2
Filing date	Jan 20, 2015
Priority date	Jan 22, 2014
Publication date	Oct 24, 2017
Grant date	Oct 24, 2017

Abstract

The present invention relates to an additive for hydraulically setting compositions, comprising a colloidally disperse preparation of at least one salt of a mono- or polyvalent metal cation and of at least one compound which is able to release an anion which forms a low-solubility salt with the metal cation, and of at least one polymeric sulphonated dispersant. The additive is suitable particularly as a slump retainer.

First claim

The invention claimed is:

1. An additive for hydraulically setting compositions, comprising a colloidally disperse preparation of at least one salt of a mono- or polyvalent metal cation, at least one compound which is able to release an anion which forms a low-solubility salt with the metal cation, and a dispersant comprising 70 to 100% by weight of the total dispersant of a polymeric sulfonated dispersant having anionic and/or anionogenic groups which is selected from sulfonated ketone-formaldehyde condensates, sulfonated melaminesulfonate-formaldehyde condensates, naphthalenesulfonate-formaldehyde condensates, lignosulfonates and sulfonated copolymers obtained by radical copolymerization and
where the metal cation is selected from Ca 2+ , Al 3+ , Fe 3+ , Fe 2+ , Zn 2+ , Mn 2+ , Cu 2+ , Mg 2+ , Sr 2+ , Ba 2+ , Li + , and mixtures thereof, and where the metal cation is present in a quantity such that the following condition (a) is met:

0.1
<

∑
i

⁢

z

K
,
i

*

n

K
,
i

∑
j

⁢

z

S
,
j

*

n

S
,
j

<
30

(
a
)

where
z K,i is the amount of the charge number of the metal cation,
n K,i is the number of mols of the weighed-in metal cation,
z S,j is the amount of the charge number of the anionic and anionogenic groups present in the polymeric dispersant,
n S,j is the number of mols of the anionic and anionogenic groups present in the weighed-in polymeric sulfonated dispersant,
the indices i and j are independent of one another and are an integer greater than 0, where i is the number of different kinds of metal cations and j is the number of different kinds of anionic and anionogenic groups present in the polymeric dispersant.

2. The additive according to claim 1 , where at least one metal cation and at least one anion are present in an amount calculated according to the following formulae:

0.01
≤

∑
l

⁢

z

A
,
l

·

n

A
,
l

∑
i

⁢

z

K
,
i

·

n

K
,
i

<
3

(
b
)

where
z K,i is the amount of the charge number of the metal cation,
n K,i is the number of mols of the weighed-in metal cation,
z A,l is the charge number of the weighed-in anion,
n A,l is the number of mols of the weighed-in anion,
the indices i and 1 are independent of one another and are an integer greater than 0, i is the number of different kinds of metal cations and 1 is the number of different kinds of anions which are able to form a low-solubility salt with the metal cation.

3. The additive according to claim 1 , where the anion is selected from an aluminate, a phosphate and a silicate.

4. The additive according to claim 1 , where the cation is selected from Ca 2+ , Al 3+ , Fe 3+ ,and Mg 2+ .

5. The additive according to claim 1 , further comprising at least one neutralizing agent.

6. The additive according to claim 5 , where the neutralizing agent is an organic monoamine, polyamine, ammonia or an alkali hydroxide.

7. The additive according to claim 1 , having a pH of 2 to 13.

8. The additive according to claim 1 , where the polymeric sulfonated dispersant is the sole dispersant or where the dispersant additionally comprises at least one polymeric dispersant comprising anionic and/or anionogenic groups and polyether side chains.

9. The additive according to claim 8 , where the dispersant comprises 70 to 90% by weight of polymeric sulfonated dispersant and 10 to 30% by weight of the polymeric dispersant comprising anionic and/or anionogenic groups and polyether side chains.

10. The additive according to claim 1 , obtained by precipitating the salt of the polyvalent metal cation in the presence of the polymeric sulfonated dispersant, to give a colloidally disperse preparation of the salt, or obtained by dispersing a freshly precipitated salt of the polyvalent metal cation in the presence of the polymeric sulfonated dispersant, to give

Assignees

• Construction Research & Technology Gmbh

Inventors

• Gädt Torben
• Grassl Harald
• Nicoleau Luc
• Dengler Joachim
• Winklbauer Martin

Classifications

• C04B28/02

  containing hydraulic cements other than calcium sulfates · CPC title

• C04B24/2647

  containing polyether side chains · CPC title

• C04B22/085

  containing nitrogen in the anion, e.g. nitrites · CPC title

• C04B2103/308

  Slump-loss preventing agents · CPC title

• C04B24/267

  containing polyether side chains · CPC title