Primerless adhesion of adhesives and sealants based on silane-functional polymers

Patent metadata

Field	Value
Publication number	US-9708517-B2
Application number	US-201414779525-A
Country	US
Kind code	B2
Filing date	Apr 9, 2014
Priority date	Apr 10, 2013
Publication date	Jul 18, 2017
Grant date	Jul 18, 2017

Abstract

The present invention relates to a composition having at least one silane-functional polymer P; and at least one catalyst for the crosslinking of silane-functional polymers, selected from among an organotitanate, an organozirconate and an organoaluminate. The composition includes at least one base; and at least one ethoxy mercaptosilane. Compositions of this type are suitable for use as adhesives, sealants or coatings, such as for plastics, including PVC.

First claim

The invention claimed is:

1. A composition comprising:
at least one silane-functional polymer P;
at least one catalyst for crosslinking of silane-functional polymers, selected from the group consisting of organotitanate, organozirconate and organoaluminate;
at least one base; and
at least one ethoxy mercaptosilane,
wherein the at least one silane-functional polymer P comprises a polymer selected from the group consisting of:
a silane-functional polyurethane polymer P1 which is obtained by reacting a silane which has at least one group that is reactive to isocyanate groups with a polyurethane polymer which has isocyanate groups,
a silane-functional polyurethane polymer P2 which is obtained by reacting an isocyanatosilane with a polymer which has functional terminal groups that are reactive to isocyanate groups, and
a combination thereof.

2. The composition according to claim 1 , wherein the silane-functional polymer P has no methoxysilane groups.

3. The composition according to claim 2 , wherein the base is selected from the group consisting of: guanidine, imidazole, imidazoline, bicyclic amidine and derivatives of these compounds.

4. The composition according to claim 3 , wherein the ethoxy mercaptosilane is 3-mercaptopropyl triethoxysilane.

5. The composition according to claim 4 , wherein a fraction of ethoxy mercaptosilane is 0.4 to 2 wt % of the composition as a whole.

6. The composition according to claim 5 , wherein the composition additionally comprises: tetraethoxysilane.

7. The composition according to claim 1 , wherein the silane-functional polymer P is an ethoxysilane-functional polymer.

8. The composition according to claim 1 , wherein the composition contains no constituents that release methanol during curing with water.

9. The composition according to claim 1 , wherein the composition contains no phthalate plasticisers.

10. The composition according to claim 1 , wherein the base is selected from the group consisting of: guanidine, imidazole, imidazoline, bicyclic amidine and derivatives of these compounds.

11. The composition according to claim 1 , wherein the base is 1,8-diazabicyclo[5.4.0]undec-7-ene.

12. The composition according to claim 1 , wherein the ethoxy mercaptosilane is 3-mercaptopropyl triethoxysilane.

13. The composition according to claim 1 , wherein a fraction of ethoxy mercaptosilane is 0.1 to 7 wt % of the composition as a whole.

14. The composition according to claim 1 , wherein the composition additionally comprises: tetraethoxysilane.

15. The composition according to claim 1 , wherein a fraction of ethoxy mercaptosilane is 0.2 to 4 wt % of the composition as a whole.

16. The composition according to claim 1 , wherein a fraction of ethoxy mercaptosilane is 0.4 to 2 wt % of the composition as a whole.

17. The composition according to claim 1 , wherein the at least one silane-functional polymer P comprises a silane-functional polyurethane polymer P1 which is obtained by reacting a silane which has at least one group that is reactive to isocyanate groups with a polyurethane polymer which has isocyanate groups.

18. The composition according to claim 1 , wherein the at least one silane-functional polymer P comprises a silane-functional polyurethane polymer P2 which is obtained by reacting an isocyanatosilane with a polymer which has functional terminal groups that are reactive to isocyanate groups.

19. A method for applying a composition comprising:
providing a composition comprising at least one silane-functional polymer P; at least one catalyst for crosslinking of silane-functional polymers, selected from the group consisting of organotitanate, organozirconate and organoaluminate; at least one base; and at least one ethoxy mercaptosilane; and
applying the composition as an adhesive, sealant or coating, wherein the composition is applied without a primer,
wherein the at least one silane-functional polymer P comprises a polymer selected from the group consisting of:
a silane-functional polyurethane polymer P1 which is obtained by reacting a silane which has at least one group that is reactive to isocyanate groups with a polyurethane polymer which has isocyanate groups,
a silane-functional polyurethane polymer P2 which is obtained by reacting an isocyanatosilane with a polymer which has functional terminal groups that are reactive to isocyanate groups, and
a combination thereof.

20. The method according to claim 19 , comprising:
applying the composition for adhesion, sealing or coating of a plastic, wherein the plastic includes PVC.

21. A method comprising:
adding an ethoxy mercaptosilane
as an adhesion promoter to a composition comprising at least one silane-functional polymer P, for improving primerless adhesion of said composition to a plastic,
wherein the at least one silane-functional polymer P comprises a polymer selected from the group consisting of:
a silane-functional polyurethane polymer P1 which is obtained by reacting a silane which has at least one group that is reactive to isocyanate groups with a polyurethane polymer which has isocyanate groups,
a silane-functional polyurethane polymer P2 which is obtained by reacting an isocyanatosilane with a polymer which has functional terminal groups that are reactive to isocyanate groups, and
a combination thereof.

22. The method according to claim 21 , wherein the plastic is PVC.

Assignees

• Sika Tech Ag

Inventors

• Mennecke Klaas
• Fedier Sara

Classifications

• C08K5/548

  containing sulfur {(C08K5/5477 takes precedence)} · CPC title

• C08K5/3465

  condensed with carbocyclic rings · CPC title

• C08G2190/00

  Compositions for sealing or packing joints · CPC title

• C09J175/08 Primary

  from polyethers · CPC title

• C08G18/10

  Prepolymer processes involving reaction of isocyanates or isothiocyanates with compounds having active hydrogen in a first reaction step · CPC title