Amine catalysts for polyurethane foams
The invention provides polyurethane and polyisocyanurate foams and methods for the preparation thereof. More particularly, the invention relates to open-celled, polyurethane and polyisocyanurate foams and methods for their preparation. The foams are characterized by a fine uniform cell structure and little or no foam collapse. The foams are produced with a polyol premix composition which comprises a combination of a hydrohaloolefin blowing agent, a polyol, a silicone surfactant, and a sterically hindered amine catalyst.
1. A polyol premix composition which has been aged for a period of at least three days and which comprises a combination of a blowing agent comprising trans-1-chloro-3,3,3-trifluoropropene (transHFCO-1233zd), a polyol, a silicone surfactant, and an amine catalyst comprising one or more morpholines and/or one or more imidazoles.
2. The polyol premix composition of claim 1 wherein the blowing agent further comprises water, formic acid, organic acids that produce CO 2 when they react with an isocyanate, hydrocarbons; ethers, esters, aldehydes, ketones, halogenated ethers; pentafluorobutane; pentafluoropropane; hexafluoropropane; heptafluoropropane; trans-1,2 dichloroethylene; methyl formate; 1-chloro-1,2,2,2-tetrafluoroethane; 1,1-dichloro-1-fluoroethane; 1,1,1,2-tetrafluoroethane; 1,1,1,2-tetrafluoroethane; 1-chloro 1,1-difluoroethane; 1,1,1,3,3-pentafluorobutane; 1,1,1,2,3,3,3-heptafluoropropane; trichlorofluoromethane; dichlorodifluoromethane; 1,1,1,3,3,3-hexafluoropropane; 1,1,1,2,3,3-hexafluoropropane; difluoromethane; difluoroethane; 1,1,1,3,3-pentafluoropropane; 1,1-difluoroethane; isobutane; normal pentane; isopentane; cyclopentane, or combinations thereof.
3. The polyol premix composition of claim 1 wherein the silicone surfactant comprises a polysiloxane polyoxyalkylene block co-polymer.
4. The polyol premix composition of claim 1 further comprising a non-silicone, non-ionic surfactant.
5. The polyol premix composition of claim 1 wherein the polyol comprises one or more of a sucrose containing polyol; phenol; a phenol formaldehyde containing polyol; a glucose containing polyol; a sorbitol containing polyol; a methylglucoside containing polyol; an aromatic polyester polyol; glycerol; ethylene glycol; diethylene glycol; propylene glycol; graft copolymers of polyether polyols with a vinyl polymer; a copolymer of a polyether polyol with a polyurea; one or more of (a) condensed with one or more of (b):
(a) glycerine, ethylene glycol, diethylene glycol, trimethylolpropane, ethylene diamine, pentaerythritol, soy oil, lecithin, tall oil, palm oil, castor oil;
(b) ethylene oxide, propylene oxide, a mixture of ethylene oxide and propylene oxide; or combinations thereof.
6. The polyol premix composition of claim 1 wherein the amine catalyst comprises dimorpholinodiethylether.
7. The polyol premix composition of claim 1 wherein the amine catalyst comprises N-ethylmorpholine.
8. The polyol premix composition of claim 1 wherein the amine catalyst comprises N-methylmorpholine.
9. The polyol premix composition of claim 1 wherein the amine catalyst comprises dimorpholinodimethylether.
10. The polyol premix composition of claim 1 wherein the amine catalyst comprises imidizole.
11. The polyol premix composition of claim 1 wherein the amine catalyst comprises n-methylimidazole.
12. The polyol premix composition of claim 1 wherein the amine catalyst comprises 1,2-dimethylimidazole.
13. A foamable composition comprising a mixture of an organic polyisocyanate and the polyol premix composition of claim 1 .
14. The foamable composition of claim 13 wherein the organic polyisocyanate comprises a polymethylene polyphenyl isocyanate, methylenebis(phenyl isocyanate), toluene diisocyanate, or combinations thereof.
15. A method of preparing a polyurethane or polyisocyanurate foam comprising reacting an organic polyisocyanate with the polyol premix composition of claim 1 .
16. A foam produced according to the method of claim 15 , wherein said foam includes closed cells that contain at least a portion of said blowing agent.