Moisture curable polyurethane compositions

• US 6,303,731 B1
• Filed: 01/20/2000
• Issued: 10/16/2001
• Est. Priority Date: 01/20/1999
• Status: Expired due to Fees

• Current Assignee: HB Fuller Company
• Original Assignee: H.B. Fuller Licensing & Financing, Inc.
• Inventors: Glasbrenner, Brian H., Simmons, Eugene R., Carlson, Brian W.
• Primary Examiner(s): GORR, RACHEL F
• Application Number:
  US09/488,261
• Time in Patent Office: 635 Days
• Field of Search: 528/59, 525/127, 525/130, 428/423.1
• US Class Current: 528/59
• CPC Class Codes: C08G 18/10 Prepolymer processes involving reaction of isocyanates or isothiocyanates with compounds having active hydrogen in a first reaction step
• CPC Class Codes: C08G 18/307 Atmospheric humidity
• CPC Class Codes: C08G 18/4866 having a low unsaturation value
• CPC Class Codes: C08G 2170/40 Compositions for pressure-sensitive adhesives
• CPC Class Codes: C08L 25/00 Compositions of, homopolymers or 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 aromatic carbocyclic ring; Compositions of derivatives of such polymers
• CPC Class Codes: C09J 175/08 from polyethers
• CPC Class Codes: Y10T 428/31551 Of polyamidoester [polyurethane, polyisocyanate, polycarbamate, etc.]

Abstract

A moisture curable composition that includes a polyurethane prepolymer comprising the reaction product of a) a polyol having an unsaturation of less than 0.02 meq/g; and b) a polyfunctional isocyanate, where the composition forms a pressure sensitive adhesive when cured, is disclosed.

Claims

1. A moisture curable composition comprising a polyurethane prepolymer comprising the reaction product of

a) a polyol having an unsaturation of less than 0.02 meq/g;

and

b) a polyfunctional isocyanate,

said composition forming a pressure sensitive adhesive when cured.

2. The composition of claim 1, wherein said polyol is a polyether polyol.

3. The composition of claim 1, wherein said polyol has an unsaturation of less than 0.01 meq/g.

4. The composition of claim 1 wherein said polyol comprises less than about 40 mole % ethylene oxide.

5. The composition of claim 1, wherein said polyol comprises less than about 20 mole % ethylene oxide.

6. The composition of claim 1 wherein said polyurethane prepolymer has an NCO:

OH ratio from about 1.5 to about 4.0.

7. The composition of claim 1 wherein said polyurethane prepolymer has an NCO:

OH ratio from about 2.0 to about 3.0.

8. The composition of claim 1 wherein said polyol has a molecular weight of greater than about 4,000 g/mole.

9. The composition of claim 1 wherein said polyol has a molecular weight of at least about 8,000 g/mole.

10. The composition of claim 1 wherein said polyol is selected from the group consisting of diols having an —

OH functionality from about 1.9 to 1.99, triols having a functionality from about 2.85 to about 2.99, and mixtures thereof.

11. The composition of claim 1 further comprising a tackifying resin.

12. The composition of claim 11 wherein said tackifying resin is a hydrocarbon tackifying resin.

13. The composition of claim 11 wherein said tackifying resin is an α

-methyl styrene resin.

19. An article comprising:

a) a substrate; and

b) the composition of claim 1 coated on a surface of said substrate.

20. A pressure sensitive adhesive composition comprising the moisture curable composition of claim 1.

14. A moisture curable composition comprising a polyurethane prepolymer comprising the reaction product of

a) a polyol having a molecular weight of at least about 6,000;

and

b) a polyfunctional isocyanate,

said composition forming a pressure sensitive adhesive when cured.

15. The moisture curable composition of claim 14, wherein said polyol has a molecular weight of at least about 8,000.

16. The moisture curable composition of claim 14, wherein said polyol has a molecular weight of at least about 12,000.

17. The moisture curable composition of claim 14, wherein said polyol has a molecular weight of from about 8,000 to about 20,000.

18. The composition of claim 14 wherein said polyurethane prepolymer has an NCO:

OH ratio from about 1.5 to about 4.0.

21. A pressure sensitive adhesive comprising the reaction product of

a) moisture, and

b) a polyurethane prepolymer comprising the reaction product of

i) a polyol having an unsaturation of less than 0.02 meq/g;

and

ii) a polyfunctional isocyanate.