Polymer dispersions, their preparation and use

Patent metadata

Field	Value
Publication number	US-11440978-B2
Application number	US-201917250136-A
Country	US
Kind code	B2
Filing date	May 30, 2019
Priority date	Jun 7, 2018
Publication date	Sep 13, 2022
Grant date	Sep 13, 2022

Abstract

A multistage emulsion polymerization process comprises polymerizing a first monomer composition comprising from 50 to 95 weight percent of vinyl acetate, from 5 to 40 weight percent of at least one vinyl ester of a C5 to C18 unsaturated carboxylic acid, and optionally up to 40 weight percent of ethylene, all based on the total weight of monomers in the first monomer composition, to produce a first stage polymer. A second monomer composition comprising 40 to 89.95 weight percent of at least one ester of methacrylic acid or a vinyl aromatic monomer, 10 to 59.95 weight percent of at least one ester of acrylic acid, and from 0.05 to 10 weight percent of at least one comonomer with acid functionality, based on the total weight of monomers in the second monomer composition, is then polymerized in the presence of the first stage polymer to produce a second stage polymer.

First claim

What is claimed is:

1. An emulsion polymerization process comprising:
(i) polymerizing, in a first stage, a first monomer composition comprising from 50 weight percent to 95 weight percent of vinyl acetate, from 5 weight percent to 40 weight percent of at least one vinyl ester of a C 5 to C 18 unsaturated carboxylic acid, optionally up to 40 weight percent of ethylene, optionally up to 40 weight percent of at least one alkyl ester of acrylic acid, and optionally up to 20 weight percent of one or more further monomers copolymerizable therewith, all based on the total weight of monomers in the first monomer composition, to produce a first stage polymer; and
(ii) polymerizing, in a second stage and in the presence of said first stage polymer, a second monomer composition comprising 40 weight percent to 89.95 weight percent of at least one alkyl ester of methacrylic acid or a vinyl aromatic monomer, 10 weight percent to 59.95 weight percent of at least one alkyl ester of acrylic acid, and from 0.05 weight percent to 10 weight percent of at least one comonomer with acid functionality, based on the total weight of monomers in the second monomer composition, to produce a second stage polymer,
wherein the weight ratio of the first stage polymer to the second stage polymer is from 95:5 to 25:75.

2. The process according to claim 1 , wherein the first stage polymer has a lower glass transition temperature, T g , than the second stage polymer.

3. The process according to claim 1 , wherein the glass transition temperature T g of the first stage polymer is at least 5° C., preferably at least 10° C., lower than the second stage polymer.

4. The process according to claim 1 , wherein the first stage polymer has a T g less than 30° C., preferably from −15 to 25° C., more preferably from −5 to 15° C.

5. The process according to claim 1 , wherein the second stage polymer has a T g of 5 to 90° C., such as from 15 to 80° C., preferably from 25 to 70° C.

6. The process according to claim 1 , wherein the at least one vinyl ester of a C 5 to C 18 unsaturated carboxylic acid comprises a vinyl ester of a C 7 to C 15 branched chain unsaturated carboxylic acid.

7. The process according to claim 6 , wherein the at least one vinyl ester of a C 7 to C 15 branched chain unsaturated carboxylic acid comprises a vinyl ester of a C 9 to C 11 branched chain unsaturated carboxylic acid.

8. The process according to claim 1 , wherein the first monomer composition comprises from 5 weight percent to 40 weight percent ethylene, based on the based on the total weight of monomers in the first monomer composition.

9. The process according to claim 1 , wherein the at least one ester of acrylic acid in the first monomer composition comprises ethyl acrylate, n-butyl acrylate, 2-octyl acrylate, 2-ethylhexyl acrylate, lauryl acrylate, and mixtures thereof.

10. The process according to claim 1 , wherein the first monomer composition further comprises from 0.05 weight percent to about 5 weight percent of at least one monomer selected from the group consisting of ethylenically unsaturated sulfonic acids, ethylenically unsaturated phosphonic and phosphoric acids, ethylenically unsaturated carboxylic acids, ethylenically unsaturated carboxylic amides, ethylenically unsaturated carboxylic anhydrides and mixtures thereof, based on the total weight of monomers in the first monomer composition.

11. The process according to claim 1 , wherein the first monomer composition further comprises from 0.05 weight percent to about 3 weight percent of at least one unsaturated silane monomer, based on the total weight of monomers in the first monomer composition.

12. The process according to claim 1 , wherein the second monomer composition comprises at least 60 weight percent, preferably at least 80 weight percent, more preferably at least 90 weight percent, based on the total weight of monomers in the second monomer composition, of the at least one ester of acrylic acid and the at least one ester of methacrylic acid.

13. The process according to claim 1 , wherein the second monomer composition contains less than 5 weight percent of any vinylaromatic monomer, based on the total weight of monomers in the second monomer composition, and preferably is free of any vinyl aromatic monomer.

14. The process according to claim 1 , wherein the at least one ester of methacrylic acid in the second monomer composition comprises methyl methacrylate, ethyl methacrylate, butyl methacrylate, isobornyl methacrylate or mixtures thereof.

15. The process according to claim 1 , wherein the at least one ester of acrylic acid in the second monomer composition comprises ethyl acrylate, n-butyl acrylate, 2-octyl acrylate, 2-ethylhexyl acrylate, lauryl acrylate, and mixtures thereof.

16. The process according to claim 1 , wherein the second monomer composition comprises from 0.1 weight percent to 10 weight percent, preferably from 0.5 weight percent to 8 weight percent, more preferably from 1 weight percent to 6 weight percent, based on the total weight of monomers in the second monomer composition, of the at least one comonomer with acid functionality.

17. The process according to claim 1 , wherein the at least one comonomer with acid functionality of the second monomer composition comprises at least one monomer selected from the group consisting of ethylenically unsaturated sulfonic acids, ethylenically unsaturated phosphonic and phosphoric acids, ethylenically unsaturated carboxylic acids, ethylenically unsaturated carboxylic anhydrides and mixtures thereof.

18. The process according to claim 1 , wherein the at least one comonomer with acid functionality of the second monomer composition comprises at least one monomer selected from the group consisting of ethylenically unsaturated carboxylic acids, ethylenically unsaturated carboxylic anhydrides and mixtures thereof.

19. The process according to claim 1 , wherein the at least one comonomer with acid functionality of the second monomer composition comprises methacrylic acid, acrylic acid, or mixtures thereof.

20. An emulsion polymerization process according to claim 1 , wherein the second monomer composition further comprises from about 0.05 weight percent to about 5 weight percent, based on the total weight of monomers in the second monomer composition, of an ethylenically unsaturated carboxylic amide.

21. A polymer dispersion produced by the process of claim 1 .

22. The polymer dispersion of claim 21 and having a minimum film forming temperature of less than 20° C., preferably less than 10° C., more preferably equal or less than 6° C.

23. The polymer dispersion of claim 21 , wherein the particles of the polymer dispersion have a weight-averaged diameter of less than 200 nm, preferably less than 150 nm, as measured by laser diffraction and polarization intensity differential scattering (PIDS) using a Beckman Coulter LS 13320 Particle Size Analyzer.

24. A coating composition comprising the polymer dispersion of claim 21 , at least one pigment and/or at least one filler.

25. The coating composition of claim 23 , wherein the coating is a wood protection paint.

26. The coating composition of claim 23 , wherein the coating is a façade paint.

27. The coating composition of claim 23 , wherein the coating is a plaster.

28. A coating produced from the coating composition of claim 23 and having a liquid water t

Assignees

• Celanese Int Corp

Inventors

• Wenzel Kerstin
• Junk Matthias
• Fichtner Thomas
• Krieger Stephan

Classifications

• C08F218/08 Primary

  Vinyl acetate · CPC title

• C08F230/085

  the monomer being a polymerisable silane, e.g. (meth)acryloyloxy trialkoxy silanes or vinyl trialkoxysilanes · CPC title

• C08F220/14

  Methyl esters {, e.g. methyl (meth)acrylate} · CPC title

• C08F220/06

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

• C08F218/10

  of monocarboxylic acids containing three or more carbon atoms · CPC title