Moisture curable hot melt adhesive composition

• US 7,914,895 B2
• Filed: 05/24/2007
• Issued: 03/29/2011
• Est. Priority Date: 05/24/2007
• Status: Expired due to Fees

• Current Assignee: HB Fuller Company
• Original Assignee: HB Fuller Company
• Inventors: Reid, Kevin J.
• Primary Examiner(s): Tran; Thao T.
• Application Number:
  US11/805,777
• Publication Number:
  US 20080292902A1
• Time in Patent Office: 1,405 Days
• Field of Search: 428/500, 428/424.6, 428/424.8, 428/423.1, 526/935, 156/332, 525/101, 525/173, 525/451
• US Class Current: 428/423.1
• CPC Class Codes: C08G 18/12 using two or more compounds having active hydrogen in the first polymerisation step
• CPC Class Codes: C08G 18/2825 having at least 6 carbon atoms
• CPC Class Codes: C08G 18/307 Atmospheric humidity
• CPC Class Codes: C08G 18/4233 derived from polymerised higher fatty acids or alcohols
• CPC Class Codes: C08G 2170/20 Compositions for hot melt adhesives
• CPC Class Codes: C09J 2475/00 Presence of polyurethane
• CPC Class Codes: Y10S 526/935 Hot melt adhesive
• CPC Class Codes: Y10T 428/12569 Synthetic resin
• CPC Class Codes: Y10T 428/31547 Of polyisocyanurate
• CPC Class Codes: Y10T 428/31551 Of polyamidoester [polyurethane, polyisocyanate, polycarbamate, etc.]
• CPC Class Codes: Y10T 428/3158 Halide monomer type [polyvinyl chloride, etc.]
• CPC Class Codes: Y10T 428/31587 Hydrocarbon polymer [polyethylene, polybutadiene, etc.]

Abstract

A moisture curable hot melt adhesive composition includes a polyurethane prepolymer, optionally a tackifying resin, and optionally a thermoplastic polymer. The polyurethane prepolymer includes a reaction product of an amorphous polyester polyol, a polyisocyanate, and a crystalline monofunctional alcohol that has a melting point of no less than about 80° C.

Claims

1. A moisture curable hot melt adhesive composition comprising:

a polyurethane prepolymer that comprises a reaction product of

an amorphous polyester polyol that is a reaction product of a monomeric polyol and a dimerized fatty acid,

a polyisocyanate, and

a crystalline monofunctional alcohol having a melting point of no less than about 80°

C.;

a thermoplastic polymer that is an ethylene vinyl acetate copolymer; and

optionally a tackifying resin,

wherein the polyester polyol is tailored to the polarity of the thermoplastic polymer such that the sum of the average equivalent weight of the monomeric polyol and the dimerized fatty acid is from about 300 to about 1500.

2. The adhesive composition of claim 1, wherein said monofunctional alcohol has carbon atoms of no less than 35.

3. The adhesive composition of claim 1, comprising

from about 10% by weight to about 80% by weight said polyurethane prepolymer,

from about 1% by weight to about 70% by weight said tackifying resin, and

from about 10% by weight to about 70% by weight said thermoplastic polymer.

4. The adhesive composition of claim 1, wherein said polyurethane prepolymer exhibits a glass transition temperature of no greater than about 10°

C.

5. The adhesive composition of claim 1, wherein said composition exhibits a melt viscosity of no greater than about 150,000 cps at 250°

F. (121°

C.).

6. The adhesive composition of claim 1, wherein the adhesive composition exhibits a peel adhesion of no less than 80% wood failure at 80°

C.

7. The adhesive composition of claim 1, wherein said dimerized fatty acid comprises a reaction product of two unsaturated carboxyl acids, each having carbon atoms of no less than 12.

14. An article comprising a first substrate, a second substrate and the adhesive composition of claim 1 sandwiched between said first and second substrates.

15. The article of claim 14, wherein at least one of said first and second substrates is selected from the group consisting of acrylonitrile-butadiene-styrene (ABS), fiber reinforced plastic (FRP), wood, wood composite panels, polyvinyl chloride (PVC), paper, impact modified polystyrene, polycarbonate, foamed polystyrene, metals, painted metals, galvanized metals, and combinations thereof.

18. A process of bonding a first substrate to a second substrate, comprising:

applying the moisture curable hot melt adhesive composition of claim 1 on at least one surface of a first substrate,

contacting said adhesive composition with a second substrate, and

curing said adhesive composition.

8. A moisture curable hot melt adhesive composition comprising

a polyurethane prepolymer that comprises a reaction product of

an amorphous polyester polyol that is a reaction product of a monomeric polyol and a dimerized fatty acid,

a polyisocyanate, and

a crystalline monofunctional alcohol having a inching point of no less than about 80°

C.;

optionally a tackifying resin; and

optionally a thermoplastic polymer,

wherein said composition is free of a crystalline or a semi crystalline polyester polyol, and exhibits a peel adhesion of no less than 80% wood failure at 80°

C.

9. The adhesive composition of claim 8, comprising

from about 10% by weight to about 80% by weight said polyurethane prepolymer,

from about 1% by weight to about 70% by weight said tackifying resin, and

from about 10% by weight to about 70% by weight said thermoplastic polymer.

10. The adhesive composition of claim 8, wherein said composition exhibits a melt viscosity of from about 5,000 cps to about 150,000 cps at 250°

F. (121°

C.).

11. The adhesive composition of claim 8, wherein said prepolymer has a weight average molecular weight of at least about 20,000 g/mol.

12. The adhesive composition of claim 8, wherein said thermoplastic polymer is selected from the group consisting of polyolefins, polyalphaolefins, polyesters, ethylene vinyl acetate, polyacrylates, polymethacrylates, polyacrylamides, polyacrylonitriles, polyimides, polyamides, polyvinyl chloride, polysiloxanes, polyurethanes, polystyrene, polyetheramide copolymers, styrene-butadiene copolymers, styrene-butadiene-styrene copolymers, styrene-isoprene-styrene copolymers, styrene-ethylene-butylene-styrene copolymers, styrene-ethylene-propylene-styrene copolymers, butyl rubber, polyisobutylene, isobutylene-isoprene copolymers, hydroxyl functional versions of any of the aforesaid polymers, and combinations thereof.

13. The adhesive composition of claim 8, wherein said amorphous polyester polyol comprises a reaction product of a polyol and a dimerized acid.

16. An article comprising a first substrate, a second substrate and the adhesive composition of claim 8 sandwiched between said first and second substrates.

17. The article of claim 16, wherein at least one of said first and second substrates is selected from the group consisting of acrylonitrile-butadiene-styrene (ABS), fiber reinforced plastic (FRP), wood, wood composite panels, polyvinyl chloride (PVC), paper, impact modified polystyrene, polycarbonate, foamed polystyrene, metals, painted metals, galvanized metals, and combinations thereof.

19. A process of bonding a first substrate to a second substrate, comprising:

applying the moisture curable hot melt adhesive composition of claim 8 on at least one surface of a first substrate,

contacting said adhesive composition with a second substrate, and

curing said adhesive composition.