Aqueous coatings containing biosurfactants as bio-adjuvants and methods for using same

Patent metadata

Field	Value
Publication number	US-11807780-B2
Application number	US-201916671971-A
Country	US
Kind code	B2
Filing date	Nov 1, 2019
Priority date	Nov 5, 2018
Publication date	Nov 7, 2023
Grant date	Nov 7, 2023

Abstract

Disclosed is an aqueous coating composition including at least one latex polymer derived from at least one monomer copolymerized or blended with a rhamnolipid and/or sophorolipid biosurfactant, which in one embodiment is a mono-rhamnolipid. Also provided is an aqueous architectural coating composition including at least one latex polymer derived from at least one monomer copolymerized or blended with a biosurfactant, at least one pigment, and water.

First claim

What is claimed is:

1. An aqueous coating composition, comprising a dispersion comprising
(a) at least one latex polymer;
(b) a biocide;
(c) a biosurfactant comprising a mono-rhamnolipid in an amount effective to reduce the necessary biocide concentration in the coating composition compared to an analogous composition that lacks the biosurfactant; and
(d) water,

wherein the biosurfactant further comprises a di-rhamnolipid, and wherein the wt % ratio of mono-rhamnolipid to di-rhamnolipid is in the range of between about 50:50 and 99.9:0.1, respectively.

2. The composition of claim 1 , wherein the wt % ratio of mono-rhamnolipid to di-rhamnolipid is in the range of between about 90:10 and 99:1, respectively.

3. The composition of claim 1 , wherein the wt % ratio of mono-rhamnolipid to di-rhamnolipid is in the range of between about 85:15 and 99.5:0.5, respectively.

4. The composition of claim 1 , wherein the wt % ratio of mono-rhamnolipid to di-rhamnolipid is in the range of between about 80:20 and 99.9:0.1, respectively.

5. The composition of claim 1 , wherein the effective amount of the biosurfactant is less than 5000 ppm of composition.

6. The composition of claim 1 , wherein the effective amount of the biosurfactant is less than 60 ppm of composition.

7. The composition of claim 1 , wherein the effective amount of the biosurfactant is from about 1 ppm to about 60 ppm of composition.

8. The composition of claim 1 , wherein the effective amount of the biosurfactant is from about 10 ppm to about 50 ppm of composition.

9. The composition of claim 1 , wherein the effective amount of the biosurfactant is from about 20 ppm to about 50 ppm of composition.

10. The composition of claim 1 , wherein the effective amount of the biosurfactant is from about 25 ppm to about 45 ppm of composition.

11. The composition according to claim 1 , wherein said at least one biocide comprises an isothiazolinone biocide.

12. The composition of claim 1 , further comprising at least one pigment and wherein the latex polymer comprises at least one acrylic monomeric unit.

13. The composition according to claim 12 , wherein the latex polymer is further derived from one or more monomers selected from the group consisting of styrene, alpha-methyl styrene, vinyl chloride, acrylonitrile, methacrylonitrile, ureido methacrylate, vinyl acetate, vinyl esters of branched tertiary monocarboxylic acids, itaconic acid, crotonic acid, maleic acid, fumaric acid, ethylene, and C 4 -C 8 conjugated dienes.

14. A process for using a biosurfactant for polymerization, comprising the step of emulsion polymerizing a reaction mixture to prepare a latex polymer, said reaction mixture comprising at least one monomer and at least one biosurfactant comprising a mono-rhamnolipid, wherein the biosurfactant further comprises a di-rhamnolipid, and wherein the wt % ratio of mono-rhamnolipid to di-rhamnolipid is in the range of between about 50:50 and 99.9:0.1, respectively.

15. The process according to claim 14 , wherein the emulsion polymerizing comprises: forming a stable aqueous pre-emulsion from the at least one monomer and the biosurfactant, and forming said reaction mixture comprising the pre-emulsion, an initiator, and water.

16. The process according to claim 14 , wherein the emulsion polymerizing comprises: forming an initiator solution comprising the initiator;
forming a stable aqueous stable pre-emulsion comprising the at least one monomer and the biosurfactant; adding the initiator solution to a reactor; and
adding the pre-emulsion to the reactor to form the reaction mixture.

17. The process according to claim 14 , further comprising at least one pigment.

18. The process according to claim 17 , wherein the at least one pigment includes at least one pigment selected from the group consisting of TiO 2 , clay, CaCO 3 , aluminum oxide, silicon dioxide, magnesium oxide, talc (magnesium silicate), barytes (barium sulfate), zinc oxide, zinc sulfite, sodium oxide, potassium oxide and mixtures thereof.

19. The process according to claim 14 , wherein the latex polymer is derived from at least one acrylic monomer selected from the group consisting of acrylic acid, acrylic acid esters, methacrylic acid, and methacrylic acid esters.

20. The process according to claim 14 , wherein the monomer comprises at least one first monomer selected from the group consisting of acrylic acid, acrylic acid esters, methacrylic acid, methacrylic acid esters, styrene, vinyl toluene, vinyl acetate, vinyl versatate, acrylonitrile, acrylamide, butadiene, ethylene, vinyl chloride and mixtures thereof.

21. The process according to claim 14 , wherein the at least one latex polymer is selected from the group consisting of pure acrylics, styrene acrylics, vinyl acrylics, acrylated ethylene vinyl acetate copolymers, and a butyl acrylate/methyl methacrylate copolymer.

22. The process according to claim 14 , comprising
forming a stable aqueous pre-emulsion from said at least one first monomer, at least one second monomer and the biosurfactant, and
forming said reaction mixture comprising the pre-emulsion, an initiator, and water,
wherein said at least one first monomer is at least one acrylic monomer selected from the group consisting of acrylic acid, acrylic acid esters, methacrylic acid, and methacrylic acid esters, and
wherein the at least one second monomer is selected from the group consisting of styrene, alpha-methyl styrene, vinyl chloride, acrylonitrile, methacrylonitrile, ureido methacrylate, vinyl acetate, vinyl esters of branched tertiary monocarboxylic acids, itaconic acid, crotonic acid, maleic acid, fumaric acid, ethylene, and C4-C8 conjugated dienes.

23. The process of claim 22 , wherein the initiator is selected from the group consisting of ammonium persulfate, hydrogen peroxide, sodium, potassium, ammonium peroxydisulfate, dibenzoyl peroxide, lauryl peroxide, ditertiary butyl peroxide, 2,2′-azobisisobutyronitrile, t-butyl hydroperoxide, benzoyl peroxide, and mixtures thereof.

24. The process of claim 22 , wherein the pre-emulsion is made of 0.001 to 10% by weight of the biosurfactant with respect to the total weight of aqueous pre-emulsion.

25. The process of claim 22 , wherein the aqueous coating composition comprises 0.5 to 10 parts by weight surfactant per 100 parts monomers used to form the latex polymer, wherein the surfactant is an emulsifier blend comprising (i) said biosurfactant and (ii) at least one non-ionic surfactant or anionic surfactant, wherein the aqueous pre-emulsion comprises sufficient emulsifier blend to stabilize the aqueous pre-emulsion.

26. The process of claim 25 , wherein at least 5 wt % of the emulsifier blend is said biosurfactant.

27. The process according to claim 22 , further comprising adding an isothiazolinone and/or isothiazolothione biocide to the emulsion after polymerization.

28. The process of claim 22 , wherein the emulsion polymerizing comprises the following sequential steps:
a) forming a stable aqueous pre-emulsion from a monomer and the biosurfactant,
b) forming said reaction mixture comprising the pre-emulsion, an initiator, and water
c) introducing the reaction mixture into a reactor and adding from 1 to 10% by weight of said pre-emulsion into said reaction mixture, and
d) heating said reaction mixture obtained at the end of step c) to a temperature of between 40° C. and 9

Assignees

• Rhodia Operations

Inventors

• Gage Laura
• Bendejacq Denis
• Jamasbi Homayoun

Classifications

• C09D5/025 Primary

  Preservatives, e.g. antimicrobial agents · CPC title

• C08F2/001

  Multistage polymerisation processes characterised by a change in reactor conditions without deactivating the intermediate polymer (C08F295/00, C08F297/00 take precedence) · CPC title

• C08F2/24

  with the aid of emulsifying agents · CPC title

• C08F2/44

  Polymerisation in the presence of compounding ingredients, e.g. plasticisers, dyestuffs, fillers · CPC title

• C08F212/08

  Styrene · CPC title