Polyurethane adhesive
View Patent ↗The present invention relates to acrylic compositions capable of bonding directly with an isocyanate-containing composition, e.g. polyurethane, and methods for manufacturing the same. The acrylic compositions of the invention have multifunctional chain transfer agents and/or multifunctional crosslinkers with isocyanate-reactive groups.
1. A method for manufacturing an article, comprising:
(a) formulating an acrylic composition having a multifunctional chain transfer agent, wherein said multifunctional chain transfer agent comprises at least one chain transfer moiety and an isocyanate-reactive group;
(b) curing the acrylic composition; and
(c) bonding the cured acrylic composition with an isocyanate-containing composition to form a bond by reacting at least a portion of the multifunctional chain transfer agent with the isocyanate-containing composition.
2. A method according to claim 1 , wherein said isocyanate-containing composition is polyurethane.
3. A method according to claim 1 , wherein said bonding occurs after applying a mixture of said isocyanate-containing composition onto said acrylic composition.
4. A method according to claim 1 , wherein said bonding occurs after coating said acrylic composition onto said isocyanate-containing composition.
5. A method according to claim 1 , wherein said isocyanate-reactive group and said isocyanate-containing composition react to produce a carbamate bond, a thiocarbamate bond, or a carbamide bond.
6. The method of claim 1 , wherein said multifunctional chain transfer agent is pentaerythritol tetra(3-mercaptopropionate).
7. A method for manufacturing an article, comprising:
(a) formulating an acrylic composition having:
i) a multifunctional crosslinker, comprising an isocyanate-reactive group; and/or
ii) a multifunctional chain transfer agent, comprising at least one chain transfer moiety and an isocyanate-reactive group;
(b) curing the acrylic composition; and
(c) reacting the cured acrylic composition with an isocyanate-containing composition to form a bond.
8. The method of claim 1 , wherein the bond formed between said acrylic composition and the isocyanate-containing composition comprises a residue of the multifunctional chain transfer agent within the acrylic composition and a residue of an isocyanate within the isocyanate-containing composition.
9. The method of claim 8 , wherein the bond comprises a carbamate bond, a thiocarbamate bond, or a carbamide bond.
10. The method of claim 1 , wherein said multifunctional chain transfer agent is selected from a group consisting of pentaerythritol tris(3-mercaptopropionate), pentaerythritol tris(2-mercaptoacetate), pentaerythritol tetra(2-mercaptoacetate), pentaerythritol tetra(3-mercaptopropionate), or trimethylolpropane tris(2-mercaptoacetate).
11. The method of claim 2 , wherein the bonding increases adhesive strength between the polyurethane and the acrylic composition, according to the chisel test.
12. The method of claim 11 , wherein the increased adhesive strength is provided by the method without a lamination step.
13. The method of claim 1 , wherein the acrylic composition comprises 0.01-10 wt. % of the multifunctional chain transfer agent.
14. The method of claim 1 , wherein the method is exclusive of a lamination step.
15. The method of claim 1 , wherein the method provides an acrylic substrate layer having a polyurethane material layer bonded thereto.
16. The method of claim 15 , wherein the provided acrylic substrate layer having a polyurethane material layer bonded thereto is prepared exclusive of a lamination step.