Expandable material

• US 7,199,165 B2
• Filed: 06/15/2004
• Issued: 04/03/2007
• Est. Priority Date: 06/26/2003
• Status: Active Grant

• Current Assignee: Zephyros, Inc.
• Original Assignee: L&L Products Inc.
• Inventors: Kassa, Abraham, Harthcock, Matthew, Apfel, Jeffrey
• Primary Examiner(s): ZEMEL, IRINA SOPJIA
• Application Number:
  US10/867,835
• Publication Number:
  US 20040266898A1
• Time in Patent Office: 1,022 Days
• Field of Search: 521/135, 521/178, 521/92, 521/94, 521/132, 521/142
• US Class Current: 521/135
• CPC Class Codes: C08J 2201/026 Crosslinking before of after foaming
• CPC Class Codes: C08J 2207/02 Adhesive
• CPC Class Codes: C08J 2331/00 Characterised by the use of copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by an acyloxy radical of a saturated carboxylic acid, or carbonic acid, or of a haloformic acid of hydrolysed polymers C08J2329/00
• CPC Class Codes: C08J 2333/06 of esters containing only carbon, hydrogen, and oxygen, the oxygen atom being present only as part of the carboxyl radical
• CPC Class Codes: C08J 2423/08 Copolymers of ethene C08J2423/16 takes precedence
• CPC Class Codes: C08J 2431/00 Characterised by the use of copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by an acyloxy radical of a saturated carboxylic acid, or carbonic acid, or of a haloformic acid of hydrolysed polymers C08J2429/00
• CPC Class Codes: C08J 9/0061 characterized by the use of several polymeric components
• CPC Class Codes: C08J 9/103 Azodicarbonamide

Abstract

An expandable material and articles incorporating the same are disclosed. The material includes a polymeric admixture; a blowing agent; a curing agent; a tackifier; and optionally, a filler or fiber.

Claims

1. An expandable material, comprising:

about 10% to about 70% by weight of a polymeric admixture, the polymeric admixture including one or more acrylates and one or more acetates;

about 6.0% to about 20% tackifier, the tackifier being a hydrocarbon resin;

about 0.1% to about 10% by weight epoxy resin;

5.5% or greater blowing agent, blowing agent accelerator or both;

a curing agent; and

one or more fillers, the one or more fillers including calcium carbonate or aramid pulp;

wherein, upon exposure to a temperature greater than about 180°

C., the expandable material expands to a volume that is at least 2000% greater than the volume of the expandable material in an unexpanded state.

2. An expandable material as in claim 1 further comprising a dispersant.

3. An expandable material as in claim 2 wherein the molecular weight of the dispersant is less than about 50,000 amu.

4. An expandable material as in claim 3 wherein the dispersant is selected from a paraffin wax or an EPDM.

5. An expandable material as in claim 1 wherein the one or more fillers includes calcium carbonate and aramid pulp.

6. An expandable material as in claim 1 wherein, upon exposure to elevated temperature, the expandable material expands to at least 3000% of its original size.

7. An expandable material as in claim 1 wherein the polymeric admixture is at least about 40% of the expandable material and the one or more acrylates comprise about 40% to about 85% of the polymeric admixture and the one or more acetates comprise about 15% to about 25% of the polymeric admixture.

9. An expandable material as in claim 1 wherein the epoxy resin is a solid.

10. An expandable material as in claim 1 wherein the curing agent is peroxide based.

11. An expandable material as in claim 1 wherein the curing agent has an activation temperature between about 60°

C. and about 110°

C.

12. An expandable material as in claim 1 wherein the one or more fillers include a fibrous filler material.

13. An expandable material as in claim 1 wherein the one or more fillers includes an aramid pulp.

14. An expandable material as in claim 1 wherein, the curing agents include a peroxide based curing agent and the hydrocarbon resin includes a hydrocarbon with two or more degrees of unsaturation.

15. An expandable material as in claim 1 wherein the polymeric admixture is at least about 40% by weight of the expandable material and the one or more acrylates comprise about 20% to about 95% of the polymeric admixture and the one or more acetates comprise about 5% to about 50% of the polymeric admixture.

8. An expandable material as in ctaim 1 further comprising an anti-oxidant.

16. An expandable material, comprising:

about 10% to about 70% by weight of a polymeric admixture, the polymeric admixture including;

i) about 20% to about 95% of one or more acrylates, the one or more acrylates including epoxidized acrylate copolymer and a copolymer of an ethylene butyl acrylate and ethylene methyl acrylate and an acrylate coagent; and

ii) about 5% to about 50% of one or more acetates, the one or more acetates including a relatively high content ethylene vinyl acetate and relatively low melt index ethylene vinyl acetate;

about 6.0% to about 20% tackifier, the tackifier being a hydrocarbon having two or more degress of unsaturation;

about 0.1% to about 10% by weight epoxy resin, the epoxy resin including at least one of a novalac type resin or a bisphenol resin;

8% or greater blowing agent and blowing agent accelerator, the blowing agent being selected from an amine or amide and the blowing agent accelerator being selected from a metal salt or an oxide;

a peroxide based curing agent;

about 3% to about 30% one or more fillers, the one or more fillers including calcium carbonate and aramid pulp; and

a dispersant, the dispersant being EPDM

wherein, upon exposure to elevated temperature, the expandable material expands to at least 3000% of its original size.

17. An expandable material as in claim 16 wherein the molecular weight of the dispersant is less than about 50,000 amu.

18. An expandable material as in claim 16 wherein, upon exposure to elevated temperature, the expandable material expands to at least 3500% of its original size.

19. An expandable material as in claim 16 further comprising a curing agent having an activation temperature between about 60°

C. and about 110°

C.