High modulus, nonconductive adhesive useful for installing vehicle windows

• US 7,361,292 B2
• Filed: 11/08/2004
• Issued: 04/22/2008
• Est. Priority Date: 11/08/2004
• Status: Expired due to Fees

• Current Assignee: Dow Global Technologies LLC (Dow, Inc.)
• Original Assignee: Dow Global Technologies, Inc. (Dow, Inc.)
• Inventors: Zhou, Lirong
• Primary Examiner(s): Kopec; Mark
• Assistant Examiner(s): THOMAS, JAISON P
• Application Number:
  US10/983,387
• Publication Number:
  US 20060096694A1
• Time in Patent Office: 1,261 Days
• Field of Search: 156/331.4, 252/511, 528/59
• US Class Current: 252/511
• 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) from about 25 to about 55 percent of one or more isocyanate functional polyether based prepolymers containing one or more organic based polymers dispersed therein having a free isocyanate content of about 0.8 to about 2.2 percent by weight based on the weight of the prepolymer;

b) from about 0.5 to about 10 percent of one or more isocyanate functional polyester based prepolymers which is solid at 23°

C.;

c) from about 1 to about 8 percent of one or more polyisocyanates having a nominal functionality of about 3 or greater;

d) from about 10 to about 18 percent of one or more conductive carbon blacks in an amount such that the composition has a dielectric constant of about 15 or less; and

e) from about 0.005 to about 2 percent one or more catalysts for the reaction of isocyanate moieties with hydroxyl groups;

wherein the percentages are based on the weight of the composition and 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 functional 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 1 wherein the organic based polymer is a thermoplastic polymer, a rubber modified thermoplastic polymer or a polyurea.

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

6. A composition according to claim 1 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 1 to about 5 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 0.1 to about 1.75 percent;

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