High modulus, nonconductive adhesive useful for installing vehicle windows

• US 20060096694A1
• Filed: 11/08/2004
• Published: 05/11/2006
• Est. Priority Date: 11/08/2004
• Status: Active Grant

• Current Assignee: Dow Global Technologies LLC (Dow, Inc.)
• Original Assignee: Dow Global Technologies, Inc. (Dow, Inc.)
• Inventors: Zhou, Lirong
• Granted Patent: US 7,361,292 B2
• Time in Patent Office: Days
• US Class Current: 156/99
• CPC Class Codes: B32B 17/10293 Edge features, e.g. inserts or holes
• 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 18/12 using two or more compounds having active hydrogen in the first polymerisation step
• CPC Class Codes: C08G 18/307 Atmospheric humidity
• CPC Class Codes: C08G 18/4072 Mixtures of compounds of group C08G18/63 with other macromolecular compounds
• CPC Class Codes: C08G 18/792 formed by oligomerisation of aliphatic and/or cycloaliphatic isocyanates or isothiocyanates
• CPC Class Codes: C09J 175/04 Polyurethanes

Abstract

The invention is a composition comprising a) one or more isocyanate functional polyether based prepolymers containing one or more organic based polymers dispersed therein; b) one or more isocyanate functional polyester based prepolymers which is solid at 23° C.; c) one or more polyisocyanates having a nominal functionality of about 3 or greater; d) one or more conductive carbon blacks in an amount such that the composition has a dielectric constant of about 15 or less; and e) one or more catalysts for the reaction of isocyanate moieties with hydroxyl groups,

wherein the composition demonstrates upon cure a modulus of 2.0 MPa or greater at 25° C. measured according to ASTM D4065; a dielectric constant of about 15 or less; a sag of an uncured sample of less than 2 mm, a press flow viscosity of about 20 to about 50 and a storage modulus of about 5.3×10⁵ Pa or greater.

Claims

1. A composition comprising

a) one or more isocyanate functional polyether based prepolymers containing one or more organic based polymers dispersed therein;

b) one or more isocyanate functional polyester based prepolymers which is solid at 23°

C.;

c) one or more polyisocyanates having a nominal functionality of about 3 or greater;

d) one or more conductive carbon blacks in an amount such that the composition has a dielectric constant of about 15 or less; and

e) one or more catalysts for the reaction of isocyanate moieties with hydroxyl groups;

wherein the composition demonstrates upon cure a modulus of 2.0 MPa or greater at 25°

C. measured according to ASTM D4065;

a dielectric constant of about 15 or less;

a sag of an uncured sample of less than 2 mm, a press flow viscosity of about 20 to about 50 and a storage modulus of about 5.3×

10⁵ Pa or greater.

2. A composition according to claim 1 wherein the isocyanate functioinal polyester prepolymer exhibits a melting point of about 50°

C. or greater.

3. A composition according to claim 2 wherein the polyfunctional polyisocyanate is an oligomer or polymer based on hexamethylene diisocyanate or methylene diphenyl diisocyanate.

4. A composition according to claim 3 wherein

a) the one or more isocyanate functional polyether based prepolymers are present in an amount of about 25 to about 55 percent;

b) the one or more isocyanate functional polyester based prepolymers are present in an amount of about 0.5 to about 10 percent;

c) one or more polyfunctional isocyanates are present in an amount of about 1 to about 8 percent;

d) one or more conductive carbon blacks are present in an amount of about 10 to about 18 percent; and

e) one or more catalysts for the reaction of isocyanate moieties with hydroxyl groups are present in an amount of about 0.005 to about 2 percent;

wherein the percentages are based on the weight of the composition.

5. A composition according to claim 4 wherein the organic based polymer is a thermoplastic polymer, a rubber modified thermoplastic polymer or a polyurea.

6. A composition according to claim 5 wherein the organic based polymer is a rubber modified thermoplastic polymer.

7. A method of bonding two or more substrates together which comprises contacting the two or more substrates together with a composition according to claim 1 disposed along at least a portion of the area wherein the substrates are in contact.

8. A method according-to claim 7 wherein the isocyanate functional polyester prepolymer exhibits a melting point of about 50°

C. or greater.

9. The method of claim 7 wherein the at least one of the substrates is window glass.

10. The method of claim 9 wherein at least one of the other substrates is a building or a vehicle.

11. The method of claim 10 wherein the substrate is a vehicle.

12. A method according to claim 7 wherein the polyfunctional polyisocyanate is an oligomer or polymer based on hexamethylene diisocyanate or methylene diphenyl diisocyanate.

13. A method according to claim 11 wherein

a) the one or more isocyanate functional polyether based prepolymers are present in an amount of about 25 to about 55 percent;

b) the one or more isocyanate functional polyester based prepolymers are present in an amount of about 0.5 to about 10 percent;

c) one or more polyfunctional isocyanates are present in an amount of about 1 to about 8 percent;

d) one or more conductive carbon blacks are present in an amount of about 10 to about 18 percent; and

e) one or more catalysts for the reaction of isocyanate moieties with hydroxyl groups are present in an amount of about 0.005 to about 2 percent;

wherein the percentages are based on the weight of the composition.

14. A method of replacing a window of a vehicle comprising

i) removing the window from the vehicle;

ii) applying a composition according to claim 1 to a replacement window or to the flange of the vehicle adapted to hold the window into the vehicle;

iii) contacting the flange of the vehicle and the replacement window with the composition disposed between the replacement window and the flange of the vehicle; and

iv) allowing the adhesive to cure.

15. The method of claim 14 wherein the vehicle can be safely driven after 60 minutes from installation of the window into the vehicle.

16. A method according to claim 15 wherein

a) the one or more isocyanate functional polyether based prepolymers are present in an amount of about 25 to about 55 percent;

b) the one or more isocyanate functional polyester based prepolymers are present in an amount of about 0.5 to about 10 percent;

c) one or more polyfunctional isocyanates are present in an amount of about 1 to about 8 percent;

d) one or more conductive carbon blacks are present in an amount of about 10 to about 18 percent; and

e) one or more catalysts for the reaction of isocyanate moieties with hydroxyl groups are present in an amount of about 0.005 to about 2 percent;

wherein the percentages are based on the weight of the composition.