Copolymers having gem-acetophone groups

1. A copolymer comprising a main hydrocarbon chain and side groups, wherein the side groups comprise carboxylic groups, polyoxyalkylate groups and gem acetophosphonate groups.

2. The copolymer according to claim 1 , wherein the polyoxyalkylate side groups are bound to the main chain through an ester, ether or amide group.

3. The copolymer according to claim 1 , wherein the gem acetophosphonate side groups fit the formula (IA) below:

wherein:

L represents a linkage to the main chain;

n represents 0 or 1;

X is a spacer group;

R 1 independently of each other is a monovalent group or a cation; and

R 2 is a hydrogen atom, a hydroxyl group or a C 1 -C 10 alkyl group.

4. The copolymer according to claim 3 , wherein L is an oxygen atom or —N(R 4 )—, wherein R 4 is hydrogen or a C 1 -C 6 alkyl group.

5. The copolymer according to claim 3 , wherein n is 0.

6. The copolymer according to claim 3 , wherein n is 1 and X is a C 1 -C 6 alkylene group.

7. The copolymer according to claim 3 , wherein R 1 is a hydrogen atom or an alkali metal, alkaline earth metal or ammonium cation.

8. The copolymer according to claim 3 , wherein R 2 is a hydroxyl group or a hydrogen atom.

9. The copolymer according to claim 1 , wherein the polyoxyalkylate groups are of the formula (II) below:

—R e —Z-A  (II)

wherein:

R e is a C 1 -C 12 alkylene group or a C═O group or further absent; and

Z is an oxygen atom or —N(R 4 )—, wherein R 4 is a hydrogen or a C 1 -C 6 alkyl group; and

A is -(QO) m —R 3 wherein:

Q represents an alkylene group with 2 to 4 carbon atoms or a mixture of these alkylene groups;

m is an integer from 1 to 500; and

R 3 represents a hydrogen atom or a C 1 -C 12 alkyl, aryl, alkylaryl or arylalkyl group.

10. The copolymer according to claim 9 , wherein R 3 is methyl.

11. The copolymer according to claim 1 , wherein the carboxylic groups fit the formula (III) below:

—C(O)—O—R d   (III)

wherein:

R d represents H or a C 1 -C 12 alkyl, aryl, alkylaryl or arylalkyl group, or an alkali metal, alkaline earth metal or ammonium cation.

12. The copolymer according to claim 2 , wherein the gem acetophosphonate side groups fit the formula (IA) below:

wherein:

L represents a linkage to the main chain;

n represents 0 or 1;

X is a spacer group;

R 1 independently of each other is a monovalent group or a cation; and

R 2 is a hydrogen atom, a hydroxyl group or a C 1 -C 10 alkyl group.

13. The copolymer according to claim 3 ,

wherein:

L is selected from the group consisting of a bond, an oxygen atom, —N(R 4 )—, a sulfur atom and an alkylene group, wherein R 4 is hydrogen or a C 1 -C 6 alkyl group;

X is an optionally substituted C 1 -C 20 alkylene group or -(QO) m —, wherein Q represents an alkylene group with 2 to 4 carbon atoms or a mixture of these alkylene groups, and m is an integer from 1 to 500; and

R 1 is selected from the group consisting of a hydrogen, a C 1 -C 6 alkyl group and -(QO) m R 5 , wherein Q represents an alkylene group with 2 to 4 carbon atoms or a mixture of these alkylene groups, m is an integer from 1 to 500, and R 5 is a hydrogen or C 1 -C 3 alkyl; or

R 1 is an alkali metal, alkaline earth metal, or ammonium cation.

14. The copolymer according to claim 12 ,

wherein:

L is selected from the group consisting of a bond, an oxygen atom, —N(R 4 )—, a sulfur atom and an alkylene group, wherein R 4 is hydrogen or a C 1 -C 6 alkyl group;

X is an optionally substituted C 1 -C 20 alkylene group or -(QO) m —, wherein Q represents an alkylene group with 2 to 4 carbon atoms or a mixture of these alkylene groups, and m is an integer from 1 to 500; and

R 1 is selected from the group consisting of a hydrogen, a C 1 -C 6 alkyl group and -(QO) m R 5 , wherein Q represents an alkylene group with 2 to 4 carbon atoms or a mixture of these alkylene groups, m is an integer from 1 to 500, and R 5 is a hydrogen or C 1 -C 3 alkyl; or

R 1 is an alkali metal, alkaline earth metal, or ammonium cation.

15. A method for preparing the copolymer according to claim 1 , comprising the steps:

(i) polymerizing a monomer bearing a carboxylic group, in the presence of a monomer bearing a polyoxyalkylate group to obtain a polymer; and

(ii) grafting the obtained polymer with a reactive gem acetophosphonate compound.

16. A method for preparing the copolymer according to claim 1 , comprising the steps:

(i) polymerizing a monomer bearing a carboxylic group to obtain a polymer comprising carboxylic groups;

(ii) esterifying part of the carboxylic groups of the obtained polymer from step (i) with polyoxyalkylate compounds to obtain a polymer comprising carboxylic groups and polyoxyalkylate groups; and

(iii) grafting the obtained polymer form step (ii) with a reactive gem acetophosphonate compound to obtain a polymer comprising carboxylic groups, polyoxyalkylate groups and gem acetophosphonate groups.

17. An admixture comprising a solution of the copolymer according to claim 1 .

18. The admixture according to claim 17 , comprising 1 to 50% by weight of the copolymer based on the total weight.

19. A method for fluidifying suspensions of mineral particles comprising the use of the copolymer according to claim 1 .

20. A method for maintaining workability of hydraulic binders comprising the use of the copolymer according to claim 1 .

21. A method for reducing the sensitivity of hydraulic compositions to clays comprising the use of the copolymer according to claim 1 .

22. A method for reducing the sensitivity of hydraulic binders to alkali metal sulfates comprising the use of the copolymer according to claim 1 .

23. A composition of mineral particles comprising the copolymer according to claim 1 .