Additive for suspensions

Patent metadata

Field	Value
Publication number	US-10106460-B2
Application number	US-201615044065-A
Country	US
Kind code	B2
Filing date	Feb 15, 2016
Priority date	Feb 16, 2015
Publication date	Oct 23, 2018
Grant date	Oct 23, 2018

Abstract

The present invention proposes a polycarboxylate ether-based additive having the general formula (I) for use as flow modifier in suspensions. The present invention further proposes a method for obtainment of such additive, wherein the method comprises the sequential steps of esterification of polyethylene glycol (PEG) with maleic anhydride (MA) and thus obtainment of a chemical product (PEGMA); and free radical polymerization in a mixture comprising acrylic acid (AA), 2-acrylamido-2 methylpropanesulfonic acid (AMPS) and PEGMA as reactants, further comprising water and an initiator, initial pH value of said mixture is within the range between 7.5 and 8.5, and any free oxygen is removed from the mixture throughout the free radical polymerization.

First claim

The invention claimed is:

1. A polycarboxylate ether-based additive (PCE) having the general formula (I) for use in suspensions,

wherein x is an integer value between 25 and 75, y is an integer value between 1 and 3, z is an integer value between 25 and 75, and n is an integer value between 23 and 46.

2. A mixture comprising the polycarboxylate ether-based additive according to the claim 1 .

3. A method for obtainment of a polycarboxylate ether-based additive for use in suspensions, wherein the method comprises the sequential steps of:
a) Esterification of polyethylene glycol (PEG) with maleic anhydride (MA) and thus obtainment of a chemical product (PEGMA);
b) Free radical polymerization of a mixture comprising acrylic acid (AA), 2-acrylamido-2 methylpropanesulfonic acid (AMPS) and PEGMA as reactants, said mixture further comprising water and an initiator; said mixture having an initial pH value within the range between 7.5 and 8.5; and any free oxygen is removed from the mixture throughout the free radical polymerization;
wherein the polycarboxylate ether-based additive (PCE) has the general formula (I)

wherein x is an integer value between 25 and 75, y is an integer value between 1 and 3, z is an integer value between 25 and 75, and n is an integer value between 23 and 46.

4. The method according to the claim 3 , wherein the step (b) comprises following sequential steps:
c) stirring upon preparation of a mixture in a reactor comprising water, acrylic acid (AA), 2-acrylamido-2 methylpropanesulfonic acid (AMPS) and PEGMA for a first time interval ranging between 25 and 35 minutes, along with removal of free oxygen from the mixture,
d) controlled addition of a first portion of initiator into the reactor, and raising the reactor temperature to a range between 48 and 53° C. and maintaining the reactor temperature within said range for a second time interval ranging between 45 and 55 minutes,
e) controlled addition of a second portion of initiator into the reactor, raising the reactor temperature to a range between 55 and 65° C. and maintaining the reactor temperature within said range for a third time interval ranging between 65 and 90 minutes,
f) raising the reactor temperature to a range between 75 and 90° C. and maintaining the reactor temperature within said range for a fourth time interval ranging between 210 and 300 minutes.

5. The method according to the claim 3 , wherein the initial pH value is within the range between 7.8 and 8.2.

6. The method according to the claim 3 , wherein the PEG in the step (a) is PEG-1000.

7. The method according to the claim 3 , wherein the esterification in the step (a) is performed with equimolar initial amounts of PEG and MA.

8. The method according to the claim 3 , wherein the esterification in the step (a) is performed for 100 to 130 minutes and with the esterification reaction temperature within the range of 85 to 95° C.

9. The method according to claim 4 , wherein the esterification in the step (a) is performed for 100 to 130 minutes and with the esterification reaction temperature within the range of 85 to 95° C.

10. The method according to the claim 3 , wherein the total reactants content in the mixture of step (b) is between 10 to 20% w/w.

11. The method according to the claim 4 , wherein the total reactants content in the mixture of step (b) is between 10 to 20% w/w.

12. The method according to the claim 3 , wherein the mixture of step (b) initially comprises 23 to 28 moles of AA and 22 to 27 moles of AMPS per each mol of PEGMA.

13. The method according to the claim 4 , wherein the mixture of step (b) initially comprises 23 to 28 moles of AA and 22 to 27 moles of AMPS per each mol of PEGMA.

14. The method according to the claim 3 , wherein the initiator of step (b) comprises an inorganic peroxide selected from the group consisting of ammonium persulfate, hydroxymethanesulfinic acid monosodium salt dehydrate, potassium persulfate, sodium persulfate, and a mixture thereof.

15. The method according to the claim 3 , wherein the initiator comprises potassium persulfate (KPS) having a mass concentration within the range 0.5% to 1.5% w/w with regard to the mass of the reactants in the mixture.

16. The method according to the claim 4 , wherein the initiator comprises potassium persulfate (KPS) having a total mass concentration within the range 0.5% to 1.5% w/w with regard to the mass of the reactants in the mixture.

17. The method according to the claim 4 , wherein the controlled addition of the initiator in at least one of step (d) and step (e) is performed throughout a time interval within the range between 4 and 8 minutes.

18. The method according to the claim 4 , wherein the first time interval ranges between 28 and 32 minutes, the second time interval ranges between 47 and 52 minutes, the third time interval ranges between 70 and 80 minutes, and the fourth time interval ranges between 225 and 260 minutes.

19. The method according to the claim 3 , wherein the removal of free oxygen is performed by sweeping with an inert gas.

Assignees

• Univ Sabanci

Inventors

• Menceloglu Yusuf
• Akhlaghi Omid
• Akbulut Özge

Classifications

• C04B28/02

  containing hydraulic cements other than calcium sulfates · CPC title

• C08F220/06

  Acrylic acid; Methacrylic acid; Metal salts or ammonium salts thereof · CPC title

• C08F230/02

  containing phosphorus · CPC title

• C04B24/2694 Primary

  containing polyether side chains · CPC title

• C04B24/165

  containing polyether side chains · CPC title