Creation of epoxy-based foam-in-place material using encapsulated metal carbonate

• US 20030060523A1
• Filed: 08/05/2002
• Published: 03/27/2003
• Est. Priority Date: 09/24/2001
• Status: Active Grant

• Current Assignee: Zephyros, Inc.
• Original Assignee: L&L Products Inc.
• Inventors: Czaplicki, Michael J.
• Granted Patent: US 6,730,713 B2
• Time in Patent Office: Days
• US Class Current: 521/50
• CPC Class Codes: C08J 2363/00 Characterised by the use of epoxy resins; Derivatives of epoxy resins
• CPC Class Codes: C08J 9/122 Hydrogen, oxygen, CO2, nitrogen or noble gases

Abstract

The invention and formulation relates to methods, materials, and products for foam-in-place materials comprising a two-component foam-in-place structural material for producing a foamed product. A first component of the system includes an epoxy-based resin preferably formulated with a coated particles, such as a metal salt, a metal carbonate encapsulated within a wax, or a polymer, (e.g., Thermoset, thermoplastic, or mixture). The metal carbonate particle may be encapsulated within a wax, shell or skin that will change state to expose the core to chemically react for initiating the production of gas for blowing. The second component is an acid that is capable of initiating polymerization of the resin. A reactive mixture is achieved through the combination of the first and second components wherein heat from the exothermic reaction of the acid with the epoxy component causes the thermoplastic shell, skin, or wax encapsulating a metal carbonate core to soften or melt thereby exposing the metal carbonate to the reactive mixture.

Claims

1. A method for producing a foamed article, comprising the steps of:

providing an epoxy resin formulation, said formulation comprising a pre-mixed epoxy resin and an encapsulated metal salt core;

providing an acid; and

combining said resin formulation and said acid to form a reactive mixture and allowing said acid to catalyze polymerization of said resin formulation and react with said coated particulate to generate a blowing gas to form voids in said polymerized epoxy resin.

2. The method for producing a foamed article recited in claim 1, wherein said acid comprises phosphoric acid.

3. The method for producing a foamed article recited in claim 1, wherein said metal carbonate particulate comprises calcium carbonate coated with meltable solid.

15. The method for producing a foamed article recited in claim 3, wherein the meltable solid is selected from the group consisting of a wax and a polymer.

4. A method for producing a foamed article, comprising the steps of:

providing an epoxy resin formulation, said formulation having an epoxy resin and an encapsulated metal carbonate core;

providing phosphoric acid; and

combining said resin formulation and said phosphoric acid to form a reactive mixture and allowing said phosphoric acid to catalyze polymerization of said resin formulation and react with said metal carbonate core to generate a blowing gas to form voids in said polymerized epoxy resin.

5. The method for producing a foamed article recited in claim 4, wherein said resin formulation comprises from about 35% to about 95% by weight of said reactive mixture.

6. The method for producing a foamed article recited in claim 4, further comprising the steps of combining an additive with said reactive mixture.

7. The method for producing a foamed article recited in claim 4, wherein said phosphoric acid comprises from about 1 to about 15% by weight of said reactive mixture.

8. The method for producing a foamed article recited in claim 6, wherein said filler is selected form the group consisting of thixotropic fillers, metal carbonates and metal bicarbonates.

9. The method for producing a foamed article recited in claim 4 wherein said epoxy resin and said encapsulated metal carbonate core are combined prior to adding said phosphoric acid.

10. The method for producing a foamed article recited in claim 9, further including the step of combining said phosphoric acid with an inert filler prior to combining said phosphoric acid with said epoxy resin and said encapsulated metal carbonate core.

11. The method for producing a foamed article recited in claim 4, wherein the molarity of said phosphoric acid is from about 10 to about 14.7.

12. The method for producing a foamed article recited in claim 4, wherein said reactive mixture further includes an additive selected form the group consisting of carbon black, ceramic microspheres, thixotropic fillers, polymer particles, rubber particles, ceramic particles, inert mineral particles and combinations thereof.

16. The method for producing a foamed article recited in claim 4, wherein the encapsulated metal carbonate core includes a meltable solid selected from the group consisting of a wax and a polymer.

13. A method for producing a foamed article, comprising the steps of:

providing an epoxy resin;

providing a metal carbonate core encapsulated by a meltable solid;

combining said epoxy resin and said metal carbonate core encapsulated by a polymer to form an epoxy-based formulation;

providing phosphoric acid;

combining said epoxy-based formulation and said phosphoric acid to form a reactive mixture and allowing said phosphoric acid to catalyze polymerization of said epoxy-based formulation and react with said metal carbonate core to generate a blowing gas to form voids in said polymerized epoxy resin.

14. The method for producing a foamed article recited in claim 13, wherein said metal carbonate core comprises calcium carbonate.

17. The method for producing a foamed article recited in claim 13, wherein the meltable solid is selected from the group consisting of a wax and a polymer.