Polymer binder for intumescent coatings

• US 20040132910A1
• Filed: 12/19/2003
• Published: 07/08/2004
• Est. Priority Date: 12/20/2002
• Status: Active Grant

• Current Assignee: Eliokem, S.A.S.
• Original Assignee: Eliokem, S.A.S.
• Inventors: Duquesne, Sophie, Delobel, Rene, Jama, Charaf, Magnet, Serge
• Granted Patent: US 7,105,605 B2
• Time in Patent Office: Days
• US Class Current: 525/191
• CPC Class Codes: C08K 3/013 Fillers, pigments or reinforcing additives
• CPC Class Codes: C08K 5/0008 Organic ingredients according to more than one of the "one dot" groups of C08K5/01 - C08K5/59
• CPC Class Codes: C08L 2205/02 containing two or more polymers of the same C08L -group
• CPC Class Codes: C08L 25/14 with unsaturated esters
• CPC Class Codes: C08L 25/16 Homopolymers or copolymers of alkyl-substituted styrenes
• CPC Class Codes: C08L 2666/04 Macromolecular compounds according to groups C08L7/00 - C08L49/00, or C08L55/00 - C08L57/00; Derivatives thereof
• CPC Class Codes: C09D 125/14 with unsaturated esters
• CPC Class Codes: C09D 125/16 Homopolymers or copolymers of alkyl-substituted styrenes
• CPC Class Codes: C09D 5/185 Intumescent paints

Abstract

The present invention discloses a copolymer composition for use in or as a polymeric binder in an intumescent coating, said copolymer composition comprising a blend of a Newtonian copolymer and of a reticulated copolymer, wherein the Newtonian copolymer is comprised of p-methylstyrene repeat units and 2-ethylhexylacrylate repeat units, and wherein the reticulated copolymer is comprised of p-methylstyrene repeat units and 2-ethylhexylacrylate repeat units. The present invention further reveals a method of manufacturing an intumescent coating comprising the step of (a) dissolving a Newtonian and a reticulated copolymer in a solvent, wherein the Newtonian copolymer is comprised of p-methylstyrene repeat units and 2-ethylhexylacrylate repeat units, wherein the reticulated copolymer is comprised of p-methylstyrene repeat units and 2-ethylhexylacrylate repeat units, and wherein the solvent is selected from the group consisting of organic solvents and water, (b) optionally, adding a chlorinated paraffin to the solvent, (c) homogenizing the mixture in the solvent, wherein one or more additives selected from the group consisting of conventional reactive pigments systems, dispersants, plasticizers, defoamers, thickeners, chlorinated paraffin solvents, waxes, fillers, fibers, and anti-settling agents are added to the solvent during the homogenizing step.

Claims

1. A copolymer composition for use in or as a polymeric binder in an intumescent coating, said copolymer composition comprising a blend of a Newtonian copolymer and of a reticulated copolymer, wherein the Newtonian copolymer is comprised of p-methylstyrene repeat units and 2-ethylhexylacrylate repeat units, and wherein the reticulated copolymer is comprised of p-methylstyrene repeat units and 2-ethylhexylacrylate repeat units.

2. A copolymer composition as specified in claim 1 wherein the Newtonian copolymer is further comprised of p-tert-butylstyrene repeat units.

3. A copolymer composition as specified in claim 1 wherein the reticulated copolymer is further comprised of 2-ethylhexylacrylate repeat units.

4. A copolymer composition as specified in claim 1 wherein the Newtonian copolymer is further comprised of 2-ethylhexylacrylate repeat units.

5. A copolymer composition as specified in claim 1 wherein the reticulated copolymer is further comprised of p-tert-butylstyrene repeat units.

6. A copolymer according to claim 1 wherein the reticulated copolymer is a thixotropic copolymers.

7. A copolymer as specified in claim 1 wherein the reticulated copolymer is a pseudo-plastic copolymers.

8. A copolymer according to claim 1 wherein the ratio of p-methylstyrene and 2-ethylhexylacrylate is within the range of 100/0 to 50/50.

9. A copolymer according to claim 1 wherein the ratio of p-methylstyrene and 2-ethylhexylacrylate is within the range of 90/10 to 75/25.

10. A copolymer according to claim 1 wherein the Newtonian copolymer is further comprised of isobutylmethacrylate.

11. A copolymer according to claim 1 wherein the reticulated copolymer is further comprised of isobutylmethacrylate.

12. A copolymer according to claim 1 wherein the Newtonian copolymers is obtained by emulsion polymerisation.

13. A copolymer according to claim 1 wherein the reticulated copolymers is obtained by emulsion polymerisation.

14. An intumescent coating which is comprised of the copolymer as specified in claim 1.

15. An intumescent coating as specified in claim 14 further comprising a foam-forming substance, a carbon forming substances and other additional conventional additives.

16. An intumescent coating as specified in claim 15 wherein the foam-forming substance is an ammonium salt of phosphoric acid.

17. An intumescent coating as specified in claim 15 wherein the carbon forming substance is selected from the group consisting of pentaerythritol, dipentaerythritol, tripentaerythritol and polycondensates of pentaerythritol.

18. An intumescent coating as specified in claim 15 wherein said intumescent coating is water based.

19. An intumescent coating as specified in claim 15 wherein said intumescent coating is solvent based.

20. A method of manufacturing an intumescent coating comprising the step of (a) dissolving a Newtonian and a reticulated copolymer in a solvent, wherein the Newtonian copolymer is comprised of p-methylstyrene repeat units and 2-ethylhexylacrylate repeat units, wherein the reticulated copolymer is comprised of p-methylstyrene repeat units and 2-ethylhexylacrylate repeat units, and wherein the solvent is selected from the group consisting of organic solvents and water, (b) optionally, adding a chlorinated paraffin to the solvent, (c) homogenizing the mixture in the solvent, wherein one or more additives selected from the group consisting of conventional reactive pigments systems, dispersants, plasticizers, defoamers, thickeners, chlorinated paraffin solvents, waxes, fillers, fibers, and anti-settling agents are added to the solvent during the homogenizing step.