PUR foam with enlarged cell structure
View Patent ↗Described are (a) a process for production of polyurethane foam by reacting one or more polyol components with one or more isocyanate components, wherein wax having a congealing point in the range from 40° C. to 90° C. is employed as an additive, (b) a polyurethane foam obtainable by said process, (c) the use of waxes having a congealing point in the range from 40° C. to 90° C. as an additive in the manufacture of polyurethane foams to coarsen the foam structure, and also (d) a polyurethane foam production composition containing a wax having a congealing point in the range from 40° C. to 90° C.
1. A process for production of polyurethane foam, said process comprising:
reacting one or more polyol components with one or more isocyanate components in the presence of an additive, wherein the additive is a wax having a predominately microcrystalline structure and having a congealing point from 50° C. to 85° C., and wherein the wax is present in an amount from 0.0001 to 0.1 parts by weight per 100 parts by weight of polyol, and wherein the wax is in a dispersed form and is present in a dispersion medium, said dispersion medium comprising at least one organic solvent.
2. The process according to claim 1 , wherein the congealing point of the wax is from 55° C. to 80° C.
3. The process according to claim 1 , wherein the wax is selected from mineral waxes, synthetic waxes and mixtures thereof.
4. The process according to claim 1 , wherein the wax has an entirely microcrystalline structure.
5. A polyurethane foam obtained by a process according to claim 1 .
6. The polyurethane foam according to claim 5 , wherein said polyurethane foam is a polyurethane flexible foam, a hot-cure flexible foam, a rigid foam, an ester foam, a viscoelastic flexible foam or a high-resilience foam (HR foam).
7. The process according to claim 1 , wherein the congealing point of the wax is from 60° C. to 75° C.
8. The process according to claim 1 , wherein the one or more isocyanate components comprise 2, 4-toylene diisocynate.
9. A polyurethane foam obtained by a process according to claim 2 .
10. A polyurethane foam obtained by a process according to claim 3 .
11. The process according to claim 1 , wherein the organic solvent is an ester of a monohydric or polyhydric alcohol.
12. The process of claim 11 , wherein the ester is selected from the group consisting of a glycerol ester and a sorbitol ester.
13. The process according to claim 1 , wherein dispersed form of the wax comprises from 0.1 to less than 10 weight percent of the wax and at least 90 weight percent of the dispersing medium.
14. A process for production of polyurethane foam, said process comprising:
reacting one or more polyol components with 2, 4-toylene diisocynate in the presence of an additive, wherein the additive is a wax having a predominately microcrystalline structure and having a congealing point from 50° C. to 85° C., and wherein the wax is present in an amount from 0.0001 to 1 parts by weight per 100 parts by weight of polyol, and wherein the wax is in a dispersed form and is present in a dispersion medium, said dispersion medium comprising a glycerol ester or a sorbital ester.
15. The process according to claim 14 , wherein the congealing point of the wax is from 60° C. to 75° C.
16. The process according to claim 14 , wherein the wax is selected from mineral waxes, synthetic waxes and mixtures thereof.
17. The process according to claim 14 , wherein the wax has an entirely microcrystalline structure.
18. A polyurethane foam obtained by a process according to claim 14 .
19. The polyurethane foam according to claim 18 , wherein said polyurethane foam is a polyurethane flexible foam, a hot-cure flexible foam, a rigid foam, an ester foam, a viscoelastic flexible foam or a high-resilience foam (HR foam).