Curable laminated article of EPDM elastomer and ethylene-containing polymer

• US 5,093,206 A
• Filed: 03/09/1990
• Issued: 03/03/1992
• Est. Priority Date: 03/09/1990
• Status: Expired due to Fees

• Current Assignee: E. I. du Pont de Nemours and Company (Corteva, Inc.)
• Original Assignee: E. I. du Pont de Nemours and Company (Corteva, Inc.)
• Inventors: Schoenbeck, Melvin A.
• Primary Examiner(s): Buffalow, Edith L.
• Application Number:
  US07/490,923
• Time in Patent Office: 725 Days
• Field of Search: 428/521, 428/500, 428/141, 525/222
• US Class Current: 428/521
• CPC Class Codes: B32B 2323/04 Polyethylene
• CPC Class Codes: B32B 2323/16 EPDM, i.e. ethylene propylene diene monomer
• CPC Class Codes: B32B 2331/04 Polymers of vinyl acetate, e.g. PVA
• CPC Class Codes: B32B 2419/06 Roofs, roof membranes
• CPC Class Codes: B32B 27/26 using curing agents
• CPC Class Codes: B32B 27/32 comprising polyolefins comprising vinyl (co)polymers or acrylic (co)polymers B32B27/30
• CPC Class Codes: C08K 3/04 Carbon
• CPC Class Codes: C08L 23/0815 Copolymers of ethene with aliphatic 1-olefins
• CPC Class Codes: C08L 23/0853 Vinylacetate
• CPC Class Codes: C08L 23/12 Polypropene
• CPC Class Codes: C08L 23/16 Elastomeric ethene-propene or ethene-propene-diene copolymers, e.g. EPR and EPDM rubbers
• CPC Class Codes: C08L 2312/00 Crosslinking
• CPC Class Codes: C08L 91/00 Compositions of oils, fats or waxes; Compositions of derivatives thereof
• CPC Class Codes: E04D 5/10 by making use of compounded or laminated materials, e.g. metal foils or plastic films coated with bitumen
• CPC Class Codes: Y10T 428/24355 Continuous and nonuniform or irregular surface on layer or component [e.g., roofing, etc.]
• CPC Class Codes: Y10T 428/31855 Of addition polymer from unsaturated monomers
• CPC Class Codes: Y10T 428/31931 Polyene monomer-containing

Abstract

A curable laminated article, useful for roofing application, comprising at least two layers, each layer comprising a blend of (a) 50-80% by weight of an ethylene/propylene/nonconjugated diene elastomer and (b) 20-50% by weight of an ethylene-containing polymer selected from the group consisting of polyethylene, an ethylene alpha-monoolefin copolymer wherein the monoolefin contains from 3-12 carbon atoms and is present in amounts of 2-8% by weight, and as ethylene/vinyl acetate copolymer having a vinyl acetate content up to about 10% by weight, and wherein each alternate layer contains either elemental sulfur as the crosslinking agent for the elastomer or a cure accelerator so that the elastomer in the laminated article subsequently cures when elemental sulfur and the accelerator in each layer migrate to an adjacent layer when the laminate is exposed to elevated temperatures.

Claims

1. A curable laminated article, useful for roofing application, comprising at least two layers, each layer comprising a blend of (a) 50-80% by weight of an ethylene/propylene/nonconjugated diene elastomer and (b) 20-50% by weight of an ethylene-containing polymer selected from the group consisting of polyethylene, ethylene alpha-monoolefin copolymers wherein the monoolefin contains from 3-12 carbon atoms and is present in amounts of 2-8% by weight, and ethylene/vinyl acetate copolymers having vinyl acetate contents up to about 10% by weight, and wherein each alternate layer contains either elemental sulfur as the crosslinking agent for the elastomer or a cure accelerator so that the elastomer in the laminated article subsequently cures when elemental sulfur and the accelerator in each layer migrate to an adjacent layer when the laminate is exposed to elevated temperatures.

2. A laminated article of claim 1 wherein the ethylene/propylene/diene elastomer contains 50-75% by weight ethylene units.

3. A laminated article of claim 1 wherein the ethylene-containing polymer is polyethylene.

4. A laminated article of claim 1 wherein the ethylene-containing polymer is an ethylene/butene copolymer.

5. A laminated article of claim 1 wherein the ethylene-containing polymer is an ethylene/vinyl acetate copolymer.

6. A laminated article of claim 1 wherein the elastomer is an ethylene/propylene/1,4-hexadiene elastomer.

7. A laminated article of claim 1 wherein the elastomer is an ethylene/propylene/ethylidene norbornene elastomer.

8. A laminated article of claim 4 wherein the elastomer is an ethylene/propylene/norboradiene/diene tetrapolymer.

9. A laminated article of claim 8 wherein the elastomer contains 50-75% by weight ethylene units.

10. A laminated article of claim 1 wherein the accelerator is a salt of a dialkyldithiocarbamate.

11. A laminated article of claim 10 wherein the accelerator is zinc dibutyldithiocarbamate.

12. A laminated article of claim 10 wherein the dialkyldithiocarbamate is zinc dimethyldithiocarbamate.

13. A laminated article of claim 1 wherein zinc oxide is present in a layer.

14. A laminated article of claim 9 wherein the elastomer is an ethylene/propylene/1,4-hexadiene/norbornadiene tetrapolymer.

15. A laminated article of claim 2 wherein the ethylene-containing polymer is an ethylene/butene copolymer and wherein the accelerator is a salt of a dialkyldithiocarbamate.

16. A laminated article of claim 4 wherein the elastomer contains about 65-72% by weight ethylene units.