Silanol-functionalized compounds for the preparation of polyurethane foams
Methods for preparing polyurethane flexible foam are described, wherein an organic polyisocyanate is reacted with an active hydrogen-containing component such as an organic polyol, in the presence of a urethane catalyst, a blowing agent, optionally a cell opener, and a siloxane-based surfactant composition as a stabilizer for the foam. The siloxane-based surfactant composition comprises a silanol-functionalized organosiloxane having general formula (I), wherein: the R groups are independently a C 1 -C 3 alkyl, phenyl, or —OSi(R) 3 ; provided that at least one R group is a hydroxyl (—OH) bonded directly to any silicon atom and X is an integer from 0-200.
1. A method for preparing a polyurethane foam which comprises contacting at least one polyisocyanate; at least one polyol; at least one catalyst; at least one blowing agent; and at least one surfactant composition comprising at least one organosiloxane of formula (I),
wherein: the R groups are C 1 -C 3 alkyl and hydroxyl (—OH); provided that one R group is a hydroxyl bonded directly to any silicon atom and X is an integer form 1-200 and the organosiloxane is present in an amount of about 0.001 to about 0.5 pphpp.
2. The method of claim 1 in which the organosiloxane is linear.
3. The method of claim 1 in which the polyol is a polyether polyol, a polyester polyol, or mixtures thereof.
4. The method of claim 1 in which the C1-C3 alkyl is methyl.
5. The method of claim 4 in which the blowing agent comprises water.
6. The method of claim 5 in which X is an integer from 1 to 60.
7. A method for preparing an open celled polyurethane foam which comprises reacting a reaction mixture comprising at least one polyisocyanate; at least one polyol; at least one blowing agent; and at least one surfactant composition in the presence of at least one tertiary amine catalyst; wherein the surfactant composition comprises at least one organosiloxane of formula (I)
wherein: the R groups are methyl, and hydroxyl (—OH); provided that at least one R group is a hydroxyl bonded directly to any silicon atom and X is an integer from 1-25 and the organosiloxane is present in an amount of about 0.001 pphpp to about 0.5 pphpp.
8. The method of claim 7 in which the polyol is a polyether polyol, a polyester polyol, or mixtures thereof.
9. The method of claim 7 in which the blowing agent comprises water.
10. An open celled polyurethane foam, obtained from a foam-forming reaction mixture containing a polyisocyanate, polyester and/or polyether polyol, a blowing agent comprising water and an effective amount of a stabilizer for the foam, wherein the stabilizer comprises a organosiloxane composition of general formula (I),
wherein: the R groups are methyl, and hydroxyl (—OH); provided that X is an integer from 1-200, the organosiloxane having 1 to 5 hydroxyls bonded directly to silicon atoms and the amount of organosiloxane is present in an amount of about 0.001 pphp to about 0.5 pphpp, the reaction mixture having an Isocyanate Index of 60 to 100.
11. The method according to claim 7 , wherein the organosiloxane is dissolved in solvents selected from the group consisting of glycols, fatty alcohols, aliphatic or aromatic hydrocarbons, and polyethers.
12. The polyurethane foam of claim 10 , wherein the shrinkage value is 25%.
13. The method of claim 1 wherein the reaction mixture has an Isocyanate Index of about 60 to about 100.
14. A method for preparing an open celled polyurethane foam which comprises contacting toluene diisocyanate; at least one polyether polyol; water; at least one amine; and at least one organosiloxane wherein the organosiloxane is dissolved in at least one solvent and has from about 1 to about 200 siloxane repeat units of formula (I)
and wherein the R groups are methyl and hydroxyl; provided that one R group is a hydroxyl bonded directly to any silicon atom and X is an integer from 1-60 and the amount of organosiloxane is from about 0.001 to about 0.5 pphpp.
15. The method of claim 1 wherein the catalyst comprises a urethane catalyst.
16. The method of claim 1 wherein the foam has a force to crush value of 175 lbf.
17. The method of claim 1 wherein the foam has a force to crush value of 203 lbf.
18. The method of claim 1 wherein the foam has an airflow rating of 2.20 ft 3 /min.
19. The method of claim 14 wherein the method comprises combining the siloxane and the polyol, adding the amine, and adding the toluene diisocyanate.
20. The method of claim 1 wherein the surfactant composition further comprises polydimethylsiloxane.
21. The method of claim 1 further comprising at least one crosslinker.
22. The method of claim 1 further comprising at least one cell opening agent.
23. The method of claim 1 wherein the polyisocyanate comprises at least one of MDI and TDI.
24. The method of claim 1 wherein the catalyst comprises at least one tertiary amine.
25. A method for preparing a polyurethane foam which comprises contacting at least one polyisocyanate; at least one polyether polyol; at least one tertiary amine catalyst; water; and a surfactant composition comprising at least one diluent and least one organosiloxane of formula (I),
wherein: the R groups are methyl and hydroxyl; provided that, the organosiloxane comprises 1 to 2 hydroxyls bonded directly to silicon atoms and X is an integer from 1-25 and the organosiloxane is used in an amount of about 0.001 to about 0.5 pphpp.
26. The method of claim 25 wherein the diluent comprises at least one of glycols, fatty alcohols, aliphatic or aromatic hydrocarbons and polyethers and the organosiloxane comprises about 0.2 to about 40 wt.% of the surfactant composition.
27. The method of claim 26 wherein the polyol, tertiary amine, water, and surfactant composition are mixed before contacting with the polyisocyanate.
28. The method of claim 26 wherein the contacting comprises mixing the polyisocyanate, polyol, tertiary amine, water and surfactant composition, and supplying a resultant mixture onto a conveyor or into a mold.
29. The method of claim 26 wherein the surfactant composition consists essentially of the diluent and the organosiloxane.