Идет обработка

Пожалуйста, подождите...

Настройки

Настройки

1. WO2017003805 - METHODS OF MAKING ACRYLAMIDE-ACRYLIC ACID COPOLYMERS

Примечание: Текст, основанный на автоматизированных процессах оптического распознавания знаков. Для юридических целей просьба использовать вариант в формате PDF

CLAIMS:

1. A composition comprising a water- in-oil latex, the water- in-oil latex comprising a water phase and an oil phase, the water phase comprising water, acrylamide, and acrylic acid and having a pH of about 3 to 5; wherein the latex further comprises a surfactant mixture consisting essentially of nonionic surfactants and comprising a block copolymer.

2. The composition of claim 1 wherein the water phase consists essentially of water, acrylamide, and acrylic acid, wherein the pH of the water phase is about 3 to 5.

3. The composition of claims 1 or 2 wherein the ratio of acrylamide to acrylic acid is about 60:40 to 99:1.

4. The composition of any of claims 1-3 wherein the block copolymer is a triblock copolymer comprising at least one block consisting essentially of ethylene glycol repeat units and having an HLB of about 4 to 6.

5. The composition of claim 4 wherein the triblock copolymer further comprises at least one block consisting essentially of hydroxyacid repeat units.

6. The composition of claim 5 wherein the hydroxyacid is 12-hydroxystearic acid.

7. The composition of any of claims 1-6 wherein the pH is about 3.5 to 4.0.

8. A method of making a water-in-oil copolymer latex, the method comprising

a. combining water and monomers to form a water phase, the monomers comprising acrylamide and acrylic acid;

b. adjusting the pH of the water phase to between about 3 and 5; c. combining a hydrocarbon solvent with a surfactant mixture to form an oil phase, the surfactant mixture consisting essentially of nonionic surfactants and comprising a block copolymer;

d. contacting the water phase and the oil phase to form a water-in-oil latex;

e. polymerizing the monomers to form a copolymer; and f. neutralizing the water phase.

9. The method of claim 8 further comprising diluting the latex with a water source after neutralizing, wherein the copolymer concentration after diluting is about 0.01 wt% to 1.00 wt%.

10. The method of claim 9 wherein the water source comprises water and a salt of Ca2+, Mg2+, Cr2+, Cr3+, Zn2+, or Al3+.

11. The method of claim 10 wherein the salt is aluminum citrate or chromium acetate.

12. The method of any of claims 8-11 wherein the neutralizing comprises contacting the composition with a neutralizing solution, the neutralizing solution comprising sodium hydroxide and an alkanolamide surfactant.

13. The method of claim 12 wherein the alkanolamide surfactant is N,N-diethanololeamide.

14. A water-in-oil copolymer latex formed using the method of any of claims

8-13.

15. Use of the composition of any of claims 1-7 to form a water-in-oil copolymer latex.