Moisture-curable, polyether urethanes with reactive silane groups and their use as sealants, adhesives and coatings

• US 6,833,423 B2
• Filed: 10/22/2003
• Issued: 12/21/2004
• Est. Priority Date: 06/18/2002
• Status: Expired due to Term

• Current Assignee: Covestro LLC (Covestro AG)
• Original Assignee: Bayer Polymers LLC (Covestro AG)
• Inventors: Roesler, Richard R., Danielmeier, Karsten, Frisch, Kurt C., Pethiyagoda, Dinesh, Crawford, Derek L.
• Primary Examiner(s): Moore, Margaret G.
• Application Number:
  US10/690,954
• Publication Number:
  US 20040127671A1
• Time in Patent Office: 426 Days
• Field of Search: 528/26, 528/28, 528/29, 528/33
• US Class Current: 528/33
• CPC Class Codes: C08G 18/0885 using additives, e.g. absorbing agents
• 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 18/283 Compounds containing ether groups, e.g. oxyalkylated monohydroxy compounds
• CPC Class Codes: C08G 18/289 containing silicon
• CPC Class Codes: C08G 18/3821 Carboxylic acids; Esters thereof with monohydroxyl compounds
• CPC Class Codes: C08G 18/3893 containing silicon
• CPC Class Codes: C08G 18/4866 having a low unsaturation value
• CPC Class Codes: C08G 18/718 containing silicon
• CPC Class Codes: C08G 2190/00 Compositions for sealing or packing joints
• CPC Class Codes: C09J 175/04 Polyurethanes
• CPC Class Codes: C09K 3/1021 Polyurethanes or derivatives thereof

Abstract

A moisture curable, alkoxysilane-functional polyether urethanes containing

a) 20 to 90% by weight, of a polyether urethane containing two or more reactive silane groups and polyether segments having a number average molecular weight (Mn) of at least 3000 and a degree of unsaturation of less than 0.04 milliequivalents/g, where the sum of Mn of the polyether segments averages 6000 to 20,000, and the reactive silane groups are incorporated by reaction of an isocyanate-reactive group with a compound of formula

OCN—Y—Si—(X)₃  (I)

b) 10 to 80% by weight, of a polyether urethane containing one reactive silane group and one or more polyether segments having Mn of 1000 to 15,000, where the reactive silane groups are incorporated by the reaction of an isocyanate group with a compound of formula

Claims

1. A moisture-curable, alkoxysilane-functional polyether urethane comprising

a) 20 to 90% by weight, based on the weight of a) and b), of a polyether urethane containing two or more reactive silane groups and one or more polyether segments, wherein the polyether segments have a number average molecular weight of at least 3000 and a degree of unsaturation of less than 0.04 milliequivalents/g, provided that the sum of the number average molecular weights of all of the polyether segments per molecule averages 6000 to 20,000, and wherein the reactive silane groups are incorporated by the reaction of an isocyanate-reactive group with a compound corresponding to the formula

2. The polyether urethane of claim 1 wherein

X represents identical or different alkoxy groups having 1 to 4 carbon atoms,

Y represents a linear radical containing 2 to 4 carbon atoms or a branched radical containing 5 to 6 carbon atoms and

R₁ represents an alkyl, cycloalkyl or aromatic group having 1 to 12 carbon atoms.

3. The polyether urethane of claim 1 wherein the reactive silane groups of component b) are incorporated as the reaction product of an isocyanate group and a compound corresponding to the formula

wherein

R₂ and R₅ are identical or different and represent organic groups which are inert to isocyanate groups at a temperature of 100°

C. or less and

R₃ and R₄ are identical or different and represent hydrogen or organic groups which are inert towards isocyanate groups at a temperature of 100°

C. or less.

4. The polyether urethane of claim 1 wherein the reactive silane groups of component b) are incorporated as the reaction product of an isocyanate group and a compound corresponding to the formula

(III)

wherein

X represents identical or different alkyl or alkoxy groups having 1 to 4 carbon atoms,

Y represents a linear radical containing 2 to 4 carbon atoms or a branched radical containing 5 to 6 carbon atoms,

R₂ and R₅ are identical or different and represent alkyl groups having 1 to 4 carbon atoms and

R₃ and R₄ represent hydrogen.

5. The polyether urethane of claim 1 wherein polyether urethane a) is present in an amount of 30 to 80% by weight and polyether urethane b) is present in an amount of 20 to 70% by weight, wherein the percentages are based on the weight of a) and b).

6. The polyether urethane of claim 2 wherein polyether urethane a) is present in an amount of 30 to 80% by weight and polyether urethane b) is present in an amount of 20 to 70% by weight, wherein the percentages are based on the weight of a) and b).

7. The polyether urethane of claim 3 wherein polyether urethane a) is present in an amount of 30 to 80% by weight and polyether urethane b) is present in an amount of 20 to 70% by weight, wherein the percentages are based on the weight of a) and b).

8. The polyether urethane of claim 4 wherein polyether urethane a) is present in an amount of 30 to 80% by weight and polyether urethane b) is present in an amount of 20 to 70% by weight, wherein the percentages are based on the weight of a) and b).

9. The polyether urethane of claim 1 wherein the polyether segments of polyether urethane a) have a number average molecular weight of at least 6000 and the polyether segments of component b) have a number average molecular weight of 3000 to 12,000.

10. The polyether urethane of claim 2 wherein the polyether segments of polyether urethane a) have a number average molecular eight of at least 6000 and the polyether segments of component b) have a number average molecular weight of 3000 to 12,000.

11. The polyether urethane of claim 3 wherein the polyether segments of polyether urethane a) have a number average molecular weight of at least 6000 and the polyether segments of component b) have a number average molecular weight of 3000 to 12,000.

12. The polyether urethane of claim 4 wherein the polyether segments of polyether urethane a) have a number average molecular weight of at least 6000 and the polyether segments of component b) have a number average molecular weight of 3000 to 12,000.

13. The polyether urethane of claim 5 wherein the polyether segments of polyether urethane a) have a number average molecular weight of at least 6000 and the polyether segments of component b) have a number average molecular weight of 3000 to 12,000.

14. The polyether urethane of claim 6 wherein the polyether segments of polyether urethane a) have a number average molecular weight of at least 6000 and the polyether segments of component b) have a number average molecular weight of 3000 to 12,000.

15. The polyether urethane of claim 7 wherein the polyether segments of polyether urethane a) have a number average molecular weight of at least 6000 and the polyether segments of component b) have a number average molecular weight of 3000 to 12,000.

16. The polyether urethane of claim 8 wherein the polyether segments of polyether urethane a) have a number average molecular weight of at least 6000 and the polyether segments of component b) have a number average molecular weight of 3000 to 12,000.

17. A sealant, adhesive or coating composition containing the moisture-curable, alkoxysilane-functional polyether urethane of claim 1.