Polyester-polyether hybrid urethane acrylate oligomer for UV curing pressure sensitive adhesives
View Patent ↗The invention is a pressure sensitive adhesive (PSA) composition, which is the ultraviolet radiation (UV) cured reaction product of a polyester-polyether-based urethane acrylate, one or more acrylate monomers, and a UV photosensitizer. The polyester-polyether-based urethane acrylate is the reaction product of between about 50 and 90 wt-% of a polyester diol having a molecular weight ranging from about 500 to 3200; between about 10 and 50 wt-% of a polyether polyol having a molecular weight ranging from about 1000 to 6000; between about 1 and 5 wt-% of a hydroxy-functional acrylate; and a polyisocyanate.
1. A pressure sensitive adhesive (PSA) composition, which comprises the ultraviolet radiation (UV) cured reaction product of:
(a) an acrylate end capped polyester-polyether-based urethane acrylate being reaction product of:
(i) between about 50 and 90 wt-% of a polyester diol having a molecular weight ranging from about 500 to about 3200;
(ii) between about 10 and 50 wt-% of a polyether polyol having a molecular weight ranging from about 1000 to about 6000;
(iii) between about 1 and about 5 wt-% of a hydroxy-functional acrylate; and
(iv) a polyisocyanate,
wherein the reaction product contains no residual isocyanate groups;
(b) one or more acrylate monomers; and
(c) a UV photosensitizer.
2. The PSA of claim 1 , wherein said polyester diol is synthesized by the condensation reaction of one or more of a C 1 –C 12 diacid or a C 1 –C 12 anhydride with a mixture of diols, wherein said polyester diol has a glass transition temperature, T g , of less than about 25° C.
3. The PSA of claim 2 , wherein said T g is less than about 0° C.
4. The PSA of claim 1 , wherein said polyether polyol is synthesized from the reaction of one or more of ethylene oxide or propylene oxide with one or more of a diol, a triol, a dithiol, a diacid, or a diamine.
5. The PSA of claim 4 , wherein said polyether polyol is synthesized from the reaction of one or more of ethylene oxide or propylene oxide with a C 2 to C 8 alkylene glycol.
6. The PSA of claim 5 , wherein said alkylene glycol is one or more of ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,2-propanediol, 1,3-butanediol, 2,3-butanediol, 1,3-pentanediol, 1,2-hexanediol, 3-methyl pentane, 1,5-diol, 1,4-cyclohexanedimethanol, diethylene glycol, or dipropylene glycol.
7. The PSA of claim 2 , wherein said polyether polyol is synthesized from the reaction of one or more of ethylene oxide or propylene oxide with a C 2 to C 8 alkylene glycol.
8. The PSA of claim 1 , wherein said hydroxy-functional acrylate is one or more of hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, hydroxybutyl (meth)acrylate, caprolactone acrylate, hydroxybutyl vinyl ether, or allyl alcohol.
9. The PSA of claim 2 , wherein said hydroxy-functional acrylate is one or more of hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, hydroxybutyl (meth)acrylate, caprolactone acrylate, hydroxybutyl vinyl ether, or allyl alcohol.
10. The PSA of claim 5 , wherein said hydroxy-functional acrylate is one or more of hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, hydroxybutyl (meth)acrylate, caprolactone acrylate, hydroxybutyl vinyl ether, or allyl alcohol.
11. The PSA of claim 1 , wherein said polyisocyanate is one or more of hexamethylene diisocyanate, toluene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), m-phenylene diisocyanate, p-phenylene diisocyanate, bitolylene diisocyanate, cyclohexane diisocyanate (CHDI), bis-(isocyanatomethyl) cyclohexane (H 6 XDI), dicyclohexylmethane diisocyanate (H 12 MDI), dimer acid diisocyanate (DDI), trimethyl hexamethylene diisocyanate, lysine diisocyanate and its methyl ester, isophorone diisocyanate, methyl cyclohexane diisocyanate, 1,5-napthalene diisocyanate, xylylene and xylene diisocyanate and methyl derivatives thereof, polymethylene polyphenyl isocyanates, chlorophenylene-2,4-diisocyanate, a polyphenylene diisocyanate, isophorone diisocyanate (IPDI), hydrogenated methylene diphenyl isocyanate (HMDI), tetramethyl xylene diisocyanate (TMXDI), hexamethylene diisocyanate (HDI), or oligomer derivatives thereof.
12. The PSA of claim 1 , which additionally comprises one or more of a wetting agent, a pigment, antioxidant, a ultraviolet absorber, an antistatic agent, a lubricant, a filler, an opacifying agent, an anti-foam agent, a rheology agent.
13. A method for formulating an ultraviolet radiation (UV) curable pressure sensitive adhesive (PSA), which comprises the steps of:
(a) forming an acrylate end capped polyester-polyether-based urethane acrylate by reacting the following ingredients:
(i) between about 50 and 90 wt-% of a polyester diol having a molecular weight ranging from about 500 to about 3200;
(ii) between about 10 and 50 wt-% of a polyether polyol having a molecular weight ranging from about 1000 to about 6000;
(iii) between about 1 and about 5 wt-% of a hydroxy-functional acrylate; and
(iv) a polyisocyanate,
wherein the reaction product contains no residual isocyanate groups;
(b) forming a reaction mixture comprising said polyester-polyether-based urethane acrylate, one or more acrylate monomers, and a UV photosensitizer; and
(c) subjecting said reaction mixture to the influence of ultraviolet radiation to form said PSA.
14. The method of claim 13 , wherein said polyester diol is synthesized by the condensation reaction of one or more of a C 1 –C 12 diacid or a C 1 –C 12 anhydride with a mixture of diols, wherein said polyester diol has a glass transition temperature, T g , of less than about 25° C.
15. The method of claim 14 , wherein said polyester diol is synthesized to have a T g of less than about 0° C.
16. The method of claim 13 , wherein said polyether polyol is synthesized from the reaction of one or more of ethylene oxide or propylene oxide with one or more of a diol, a triol, a dithiol, a diacid, or a diamine.
17. The method of claim 16 , wherein said polyether polyol is synthesized from the reaction of one or more of ethylene oxide or propylene oxide with a C 2 to C 8 alkylene glycol.
18. The method of claim 17 , wherein said alkylene glycol is one or more of ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,2-propanediol, 1,3-butanediol, 2,3-butanediol, 1,3-pentanediol, 1,2-hexanediol, 3-methyl pentane, 1,5-diol, 1,4-cyclohexanedimethanol, diethylene glycol, or dipropylene glycol.
19. The method of claim 14 , wherein said polyether diol is synthesized from the reaction of one or more of ethylene oxide or propylene oxide with a C 2 to C 8 alkylene glycol.
20. The method of claim 1 , wherein said hydroxy-functional acrylate is one or more of hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, hydroxybutyl (meth)acrylate, caprolactone acrylate, hydroxybutyl vinyl ether, or allyl alcohol.
21. The method of claim 14 , wherein said hydroxy-functional acrylate is one or more of hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, hydroxybutyl (meth)acrylate, caprolactone acrylate, hydroxybutyl vinyl ether, or allyl alcohol.
22. The method of claim 17 , wherein said hydroxy-functional acrylate is one or more of hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, hydroxybutyl (meth)acrylate, caprolactone acrylate, hydroxybutyl vinyl ether, or allyl alcohol.
23. The method of claim 13 , wherein said polyisocyanate is one or more of hexamethylene diisocyanate, toluene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), m-phenylene diisocyanate, p-phenylene diisocyanate, bitolylene diisocyanate, cyclohexane diisocyanate (CHDI), bis-(isocyanatomethyl) cyclohexane (H 6 XDI), dicyclohexylmethane diisocyanate (H 12 MDI), dimer acid diisocyanate (DDI), trimethyl hexamethylene diisocyanate, lysine diisocyanate and its methyl ester, isophorone diisocyanate, methyl cyclohexane diisocyanate, 1,5-napthalene diisocyanate, xylylene and xylene diisocyanate and methyl derivatives thereof, polymethylene polyphenyl isocyanates, chlorophenylene-2,4-diisocyanate, a polyphenylene diisocyanate, isophorone diisocyanate (IPDI), hydrogenated methylene diphenyl isocyanate (HMDI), tetramethyl xylene diisocyanate (TMXDI), hexamethylene diisocyanate (HDI), or oligomer derivatives thereof.
24. The method of claim 13 , which additionally comprises one or more of a wetting agent, a pigment, antioxidant, a ultraviolet absorber, an antistatic agent, a lubricant, a filler, an opacifying agent, an anti-foam agent, a rheology agent.
25. The cured reside of the PSA of claim 1 .
26. The cured reside of the PSA of claim 3 .
27. The cured reside of the PSA of claim 8 .
28. The cured reside of the PSA of claim 11 .