Polyurethane foam premixes containing halogenated olefin blowing agents and foams made from same

1. A method of forming a thermoset foam comprising:

forming a polyol premix comprising: (a) from about 60 wt % to about 95 wt % of polyol; (b) from about 1 wt % to about 30 wt % of blowing agent, said blowing agent comprising from about 7 wt % to about 98 wt % of 1,1,1,4,4,4hexafluorobut-2-ene, wherein said 1,1,1,4,4,4hexafluorobut-2-ene consists essentially of 1,1,1,4,4,4hexafluorobut-2-ene (1336mzzm(Z)); (c) at least one surfactant; and (d) a catalyst system comprising metal-based catalyst, wherein said metal based-catalyst consists essentially of at least one bismuth-based metal catalyst;

storing said polyol premix for a period of at least one month;

forming a foamable composition by combining after said storing step said polyol premix with a reactive component,

forming a foam from said foamable composition, provided that said polyol premix is sufficiently free of non-bismuth-based catalyst such that said foam has a cream time of not greater than 10 seconds.

2. The method of claim 1 wherein said foam formed from said polyol premix has a cream time of not greater than 10 seconds when aged for 3 months at room temperature.

3. The method of claim 1 wherein said bismuth-metal catalyst comprises a catalyst represented by the formula Bi—(R) 3 , wherein each R is independently selected from the group consisting of a hydrogen, a halide, a hydroxide, a sulfate, a carbonate, a cyanate, a thiocyanate, an isocyanate, a isothiocyanate, a carboxylate, an oxalate, a C1-C10 alkane, a C1-C10 alkene, a C1-C10 alkyne, a heteroalkyl group, an aryl group, a ketone, an aldehyde, an esters, an ether, an alcohol, an alcoholate, a phenolate, a glycolates, a thiolates, an octoate, a hexanoate, and combinations thereof, where any of the foregoing R groups may be independently substituted or unsubstituted.

4. The method of claim 1 wherein said bismuth-metal catalyst is selected from the group consisting of a bismuth carboxylate, a bismuth octoate, bismuth hexanoate, bismuth 2-ethylhexanoate, a bismuth acetylacetonate, bismuth ethoxide, bismuth propoxide, bismuth butoxide, bismuth isopropoxide, bismuth butoxide, a derivative thereof, and combinations thereof.

5. The polyol premix of claim 1 wherein said bismuth-metal catalyst comprises a bismuth carboxylate or a derivative thereof.

6. The method of claim 1 wherein said bismuth-metal catalyst comprises bismuth 2-ethylhexanoate, or a derivative thereof.

7. The method of claim 1 wherein said at least one bismuth-based metal catalyst is present in the composition in an amount to provide foam formed from said aged polyol premix with a cream time of less than about 6 seconds after aging for 3 months at room temperature.

8. The method of claim 1 wherein said polyol premix further comprises an aromatic amine catalyst comprising a compound of the formula [R m C6H n —NH2] x , where m=0, 1, 2, 3, 4, or 5, n=0, 1, 2, 3, 4, or 5, x=1, or 2, and m+n+x=6 and wherein each R may be independently selected from the group consisting of comprises a hydrogen, a halide, a hydroxide, a sulfate, a carbonate, a cyanate, a thiocyanate, an isocyanate, a isothiocyanate, a carboxylate, an oxalate, a nitrate, a substituted or unsubstituted alkyl, heteroalkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heteroaryl group, and combinations thereof.

9. The method of claim 8 wherein at least one R is selected from the group consisting of aniline, fluoroaniline, chloroaniline, bromoaniline, nitroaniline, aminotoluene, fluoroaminotoluene, chloroaminotoluene, bromoaminotoluene, nitroaminotoluene, diaminobenzene, fluorodiaminobenzene, chlorodiaminobenzene, bromodiaminobenzene, nitrodiaminobenzene, diaminotoluene, 3,5-diethyltoluene-2,4-diamine, 3,5-diethyltoluene-2,6-diamine, dimethylthiotoluenediamine, benzidine, (di)fluorobenzidine, (di)chlorobenzidine, (di)bromobenzidien, (di)nitrobenzidine, (di)methylbenzidine, (di)ethylbenzidine, diaminodiphenylmethane, (di)fluorodiaminodiphenylmethane, (di)chlorodiaminodiphenylmethane, (di)bromodiaminodiphenylmethane, (di)methyldiaminodiphenylmethane, (di)ethyldiaminodiphenylmethane, diaminobenzophenone, (di)fluorodiaminobenzophenone, (di)chlorodiaminobenzophenone, (di)bromodiaminobenzophenone, (di)methyldiaminobenzophenone, (di)ethyldiaminobenzophenone, aminoimidazole, aminopyridine, bipyridinamine and combinations thereof.

10. The method of claim of claim 8 wherein the aromatic amine catalyst comprises a compound of the formula [R′—NH 2 ] x , wherein x=0, 1 or 2 and R′ comprises a heteroaryl ring moiety having at least one of N, O, or S, and from 2-20 carbon atoms and may be optionally substituted.

11. The method of claim 1 wherein said polyol premix further comprises a co-blowing agent selected from the group consisting of water, hydrocarbon, fluorocarbon, chlorocarbon, hydrochlorofluorocarbon, hydrofluorocarbon, halogenated hydrocarbon, ether, ester, alcohol, aldehyde, ketone, organic acid, gas generating material, and combinations thereof.

12. The method of claim 1 wherein said step of forming a foamable composition comprises combining an isocyanate component with said aged polyol premix composition, wherein said aged polyol premix composition comprises: (a) from about 60 wt % to about 95 wt % of polyol; (b) from about 1 wt % to about 30 wt % of blowing agent, said blowing agent comprising from about 7 wt % to about 98 wt % 1,1,1,4,4,4hexafluorobut-2-ene (1336mzzm(Z)); (c) at least one surfactant; and (d) a catalyst system comprising metal-based catalyst, wherein said metal based-catalyst consists essentially of at least one bismuth-based metal catalyst and being sufficiently free of non-bismuth-based catalyst to provide said foamable composition with an initial cream time of less than about 10 seconds and wherein said foamable composition combined with said aged polyol premix has a cream time of not greater than 10 seconds after aging for 3 months at room temperature, said weight percentages of each of (a) through (b) being based on the total of components (a)-(d) in the polyol premix.

13. The method of claim 12 wherein said at least one bismuth-based metal catalyst is present in the aged polyol premix in an amount to provide foam formed from said foamable composition with a cream time of less than about 6 seconds after aging for 3 months at room temperature.

14. The method of claim 13 wherein said polyol premix comprises (a) from about 65 wt % to about 95 wt % of at least one polyol; (b) from about 3 wt % to about 30 wt % of blowing agent, said blowing agent comprising from about 10% to about 95% of 1,1,1,4,4,4hexafluorobut-2-ene (1336mzzm(Z)).

15. A foam formed from the method of claim 1 .

16. A method of forming a thermoset foam comprising:

forming a polyol premix comprising a combination of: (i) an isocyanate component and (ii) an aged polyol premix composition comprising: (a) from about 60 wt % to about 95 wt % of at least one polyol; (b) from about 1 wt % to about 30 wt % of blowing agent, said blowing agent comprising from about 7 wt % to about 98 wt % of 1,1,4,4,4-hexafluorobut-2-ene, wherein said 1,1,4,4,4-hexafluorobut-2-ene consists essentially of 1,1,4,4,4-hexafluorobut-2-ene (1336mzzm(Z)); (c) at least one surfactant; and (d) a catalyst system comprising metal-based catalyst, wherein said metal based-catalyst consists essentially of at least one bismuth-based metal catalyst and being sufficiently free of non-bismuth-based catalyst to provide said foamable composition with at least about 10% front-end reactivity improvement relative to the same foamable composition in the absence of said bismuth-based metal catalyst.

17. The method of claim 16 wherein said at least one bismuth-metal catalyst comprises a catalyst represented by the formula Bi—(R)3, wherein each R is independently selected from the group consisting of a hydrogen, a halide, a hydroxide, a sulfate, a carbonate, a cyanate, a thiocyanate, an isocyanate, a isothiocyanate, a carboxylate, an oxalate, a nitrate, a Cl-C10 alkane, a C1-C10 alkene, a C1-C10 alkyne, a heteroalkyl group, an aryl group, a ketone, an aldehyde, an esters, an ether, an alcohol, an alcoholate, a phenolate, a glycolates, a thiolates, an octoate, a hexanoate, and combinations thereof, where any of the foregoing R groups may be independently substituted or unsubstituted.

18. The method of claim 17 wherein said at least one bismuth-metal catalyst is selected from the group consisting of a bismuth carboxylate, a bismuth octoate, bismuth hexanoate, bismuth 2-ethylhexanoate, a bismuth acetylacetonate, bismuth ethoxide, bismuth propoxide, bismuth butoxide, bismuth isopropoxide, bismuth butoxide, a derivative thereof, and combinations thereof.

19. The method of claim 18 wherein the amount of said at least one bismuth-based metal catalyst is effective to provide said foamable composition with at least about 20% front-end reactivity improvement relative to the same foamable composition in the absence of said bismuth-based metal catalyst.

20. A method of forming a thermoset foam comprising:

forming a polyol premix comprising: (a) from about 60 wt % to about 95 wt % of polyol; (b) from about 1 wt % to about 30 wt % of blowing agent, said blowing agent comprising from about 7 wt % to about 98 wt % of 1,1,4,4,4-hexafluorobut-2-ene, wherein said 1,1,4,4,4-hexafluorobut-2-ene consists essentially of 1,1,1,4,4,4hexafluorobut-2-ene (1336mzzm(Z)); (c) at least one surfactant; and (d) a catalyst system comprising metal-based catalyst, wherein said metal based-catalyst consists essentially of at least one bismuth-based metal catalyst;

using said polyol premix after a storage period of at least one month to form a foamable composition by combining said polyol premix with a reactive component,

forming a foam by spraying said foamable composition, where said sprayed foam has a cream time of not greater than 10 seconds.