Insulating thermoplastic foams made with methyl formate-based blowing agents
View Patent ↗A blowing agent blend for making thermoplastic polymer foams comprises methyl formate. The blowing agent blend can further comprise at least one co-blowing agent. The co-blowing agent is either a physical co-blowing agent (e.g. an inorganic agent, a hydrocarbon, a halogenated hydrocarbon, a hydrocarbon with polar, functional group(s), water or any combination thereof), or a chemical co-blowing agent, or combinations thereof. The thermoplastic polymer foam can be an alkenyl aromatic polymer foam, e.g. a polystyrene foam. The blowing agent blend can comprise any combination of methyl formate and one or more co-blowing agents. The methyl formate-based blowing agent blends produce stable foams for various applications, including containers, packaging systems, as well as insulation boards and building materials. A process for the preparation of such foams is also provided.
1. A process for making an alkenyl aromatic polymer foam board comprising:
melting a thermoplastic alkenyl aromatic polymer;
dissolving an effective amount of a blowing agent blend in the alkenyl aromatic polymer to define a mixture, the blowing agent blend comprising greater than about 39 weight percent of methyl formate;
forming an extrudate from the mixture; and
expanding the extrudate to produce the alkenyl aromatic polymer foam board, wherein the alkenyl aromatic polymer foam board has a thickness of at least 0.5 inch and an R value of about 4 per inch or greater.
2. The process of claim 1 , wherein the blowing agent blend further includes at least one co-blowing agent selected from the group consisting of propane, butane, and pentane, or an isomer thereof.
3. The process of claim 1 , wherein the blowing agent blend further includes carbon dioxide or water.
4. The process of claim 1 , wherein the blowing agent blend further includes a chemical blowing agent.
5. The process of claim 1 , wherein the average cell size of the alkenyl aromatic polymer foam board is about 160 to about 285 microns.
6. The process of claim 1 , wherein the extrudate comprises from about 1 to about 18 weight percent blowing agent.
7. The process of claim 6 , wherein the extrudate comprises from about 4 to about 10 weight percent blowing agent.
8. The process of claim 1 , wherein the alkenyl aromatic polymer foam board has a density of about 1.5 to about 3.9 lb/ft 3 .
9. The process of claim 1 , wherein the alkenyl aromatic polymer is polystyrene.
10. A process for making an alkenyl aromatic polymer foam board comprising:
melting a thermoplastic alkenyl aromatic polymer;
dissolving an effective amount of a blowing agent blend in the alkenyl aromatic polymer to define a mixture, the blowing agent blend consisting of about 5 to about 85 weight percent of methyl formate and about 15 to about 95 weight percent of at least one co-blowing agent selected from the group consisting of C 2 to C 5 hydrocarbon, carbon dioxide and water;
forming an extrudate from the mixture; and
expanding the extrudate to produce the alkenyl aromatic polymer foam board, wherein the alkenyl aromatic polymer foam board has a thickness of at least 0.5 inch and an R value of about 4 per inch or greater, and wherein the blowing agent blend is the sole blowing agent in the polymer.
11. The process of claim 10 , wherein the average cell size of the alkenyl aromatic polymer foam board is about 160 to about 285 microns.
12. The process of claim 10 , wherein the extrudate comprises from about 1 to about 18 weight percent blowing agent.
13. The process of claim 12 , wherein the extrudate comprises from about 4 to about 10 weight percent blowing agent.
14. The process of claim 10 , wherein the alkenyl aromatic polymer foam board has a density of about 1.5 to about 3.9 lb/ft 3 .
15. The process of claim 10 , further comprising adding at least one additive selected from the group consisting of fillers, colorants, light and heat stabilizers, anti-oxidants, acid scavengers and stability control agents to the polymer.
16. The process of claim 10 , further comprising mixing a nucleating agent with the alkenyl aromatic polymer prior to the extrudate forming step.
17. A process for making an alkenyl aromatic polymer foam board comprising:
melting a thermoplastic alkenyl aromatic polymer;
dissolving an effective amount of a blowing agent blend in the alkenyl aromatic polymer to define a mixture, the blowing agent blend consisting essentially of methyl formate and ethane;
forming an extrudate from the mixture; and
expanding the extrudate to produce the alkenyl aromatic polymer foam board, the alkenyl aromatic polymer foam board having a thickness of at least 0.5 inch and an R value of about 4 per inch or greater, wherein the blowing agent blend is the sole blowing agent in the polymer.
18. The process of claim 17 , wherein the blowing agent blend consists of methyl formate and ethane.
19. The process of claim 17 , wherein the alkenyl aromatic polymer foam board has a density of about 1.5 to about 3.9 lb/ft 3 .
20. The process of claim 17 , wherein the extrudate comprises from about 1 to about 18 weight percent blowing agent.
21. The process of claim 20 , wherein the extrudate comprises from about 4 to 10 weight percent blowing agent.
22. The process of claim 17 , wherein the average cell size of the alkenyl aromatic polymer foam board is about 160 to about 285 microns.
23. The process of claim 17 , wherein the process further comprises mixing a nucleating agent with the alkenyl aromatic polymer prior to the extrudate forming step.
24. The process of claim 17 wherein the alkenyl aromatic polymer foam board is a substantially closed-cell structure.
25. The process of claim 17 , wherein the alkenyl aromatic polymer foam board is dimensionally stable.
26. The process of claim 17 , further comprising adding at least one additive selected from the group consisting of fillers, colorants, light and heat stabilizers, anti-oxidants, acid scavengers and stability control agents to the polymer.
27. A process for making an alkenyl aromatic polymer foam board comprising:
melting a thermoplastic alkenyl aromatic polymer;
dissolving an effective amount of a blowing agent blend in the alkenyl aromatic polymer to define a mixture, the blowing agent blend consisting of methyl formate and 1,1,1,2-tetrafluoroethane (HFC-134a);
forming an extrudate from the mixture; and
expanding the extrudate to produce the alkenyl aromatic polymer foam board, wherein the alkenyl aromatic polymer foam board has a thickness of at least 0.5 inch and an R value of about 4 per inch or greater, and wherein the blowing agent blend is the sole blowing agent in the polymer.
28. The process of claim 27 , the blowing agent blend consisting of about 40 to about 55 percent by weight methyl formate and 45 to 60 percent by weight 1,1,1 ,2-tetrafluoroethane (HFC-134a).
29. The process of claim 26 , wherein the average cell size of the alkenyl aromatic polymer foam board is about 180 to about 285 microns.
30. The process of claim 26 , wherein the extrudate comprises from about 1 to about 18 weight percent blowing agent.
31. The process of claim 30 , wherein the extrudate comprises about 4 to about 10 weight percent blowing agent.
32. The process of claim 26 , wherein the alkenyl aromatic polymer foam board has a density of about 2.5 to about 3.9 lb/ft 3 .
33. The process of claim 27 , further comprising adding at least one additive selected from the group consisting of fillers, colorants, light and heat stabilizers, anti-oxidants, acid scavengers and stability control agents to the polymer.
34. The process of claim 27 , further comprising mixing a nucleating agent with the alkenyl aromatic polymer prior to the extrudate forming step.
35. A process for making an alkenyl aromatic polymer foam board comprising:
melting a thermoplastic alkenyl aromatic polymer;
dissolving an effective amount of a blowing agent blend in the alkenyl aromatic polymer to define a mixture, the blowing agent blend consisting of methyl formate and 1,1,1,2-tetrafluoroethane (HFC-134a) and carbon dioxide;
forming an extrudate from the mixture; and
expanding the extrudate to produce the alkenyl aromatic polymer foam board, wherein the alkenyl aromatic polymer foam board has a thickness of at least 0.5 inch and an R value of about 4 per inch or greater, and wherein the blowing agent blend is the sole blowing agent in the polymer.
36. The process of claim 35 , the blowing agent blend consisting of about 40 to about 55 percent by weight methyl formate, of about 45 to about 60 percent by weight 1,1,1 ,2-tetrafluoroethane (HFC-134a) and of about 0 to about 4 percent by weight carbon dioxide.
37. The process of claim 35 , wherein the alkenyl aromatic polymer foam board has a density of about 2.5 to about 3.9 lb/ft 3 .
38. The process of claim 35 , wherein the extrudate comprises from about 1 to about 18 weight percent blowing agent.
39. The process of claim 38 , wherein the extrudate comprises from about 4 to about 10 weight percent blowing agent.
40. The process of claim 35 , further comprising adding at least one additive selected from the group consisting of fillers, colorants, light and heat stabilizers, anti-oxidants, acid scavengers and stability control agents to the polymer.
41. The process of claim 35 , further comprising mixing a nucleating agent with the alkenyl aromatic polymer prior to the extrudate forming step.
42. An alkenyl aromatic polymer foam board prepared by a process comprising:
melting a thermoplastic alkenyl aromatic polymer;
dissolving an effective amount of a blowing agent blend in the alkenyl aromatic polymer to define a mixture, the blowing agent blend comprising greater than about 39 weight percent of methyl formate;
forming an extrudate from the mixture; and
expanding the extrudate to produce the alkenyl aromatic polymer foam board, wherein the alkenyl aromatic polymer foam board has a thickness of at least 0.5 inch and an R value of 4 per inch or greater.
43. The alkenyl aromatic polymer foam board of claim 42 , wherein the blowing agent blend includes a chemical blowing agent.
44. The alkenyl aromatic polymer foam board of claim 42 , wherein the blowing agent blend further comprises at least one co-blowing agent selected from the group consisting of propane, butane, and pentane, or an isomer thereof.
45. The alkenyl aromatic polymer foam board of claim 42 , wherein the blowing agent blend further includes carbon dioxide or water.
46. The alkenyl aromatic polymer foam board of claim 42 , wherein the extrudate comprises from about 1 to about 18 weight percent blowing agent.
47. The alkenyl aromatic polymer foam board of claim 46 , wherein the extrudate comprises from about 4 to about 10 weight percent blowing agent.
48. The alkenyl aromatic polymer foam board of claim 42 , further comprising mixing a nucleating agent with the thermoplastic alkenyl aromatic polymer prior to the extrudate forming step.
49. The alkenyl aromatic polymer foam board of claim 42 , wherein the alkenyl aromatic polymer foam board is a substantially closed-cell structure.
50. The alkenyl aromatic polymer foam board of claim 42 , wherein the alkenyl aromatic polymer foam board is dimensionally stable.
51. The alkenyl aromatic polymer foam board of claim 42 , wherein the alkenyl aromatic polymer foam board has a density of about 1.5 to about 3.9 lb/ft 3 .
52. An alkenyl aromatic polymer foam board prepared by a process comprising:
melting a thermoplastic alkenyl aromatic polymer;
dissolving an effective amount of a blowing agent blend in the alkenyl aromatic polymer to define a mixture, the blowing agent blend consisting of methyl formate, 1,1,1,2-tetrafluoroethane (HFC-134a) and optionally carbon dioxide;
forming an extrudate from the mixture; and
expanding the extrudate to produce the alkenyl aromatic polymer foam board, wherein the alkenyl aromatic polymer foam board has a thickness of at least 0.5 inch and an R value of about 4 per inch or greater, and wherein the blowing agent blend is the sole blowing agent in the polymer.
53. The alkenyl aromatic polymer foam board of claim 52 , the blowing agent blend consisting of about 40 to about 55 percent by weight methyl formate, of about 45 to about 60 percent by weight 1,1,1,2-tetrafluoroethane (HFC-134a) and of about 0 to about 4 percent by weight carbon dioxide.
54. The alkenyl aromatic polymer foam board of claim 52 , wherein the alkenyl aromatic polymer foam board has a density of about 2.5 to about 3.9 lb/ft 3 .
55. The alkenyl aromatic polymer foam board of claim 52 , wherein the average cell size of the alkenyl aromatic polymer foam board is about 160 to about 285 microns.
56. The alkenyl aromatic polymer foam board of claim 52 , wherein the extrudate comprises from about 1 to about 18 weight percent blowing agent.
57. The alkenyl aromatic polymer foam board of claim 56 , wherein the extrudate comprises from about 4 to about 10 weight percent blowing agent.
58. The alkenyl aromatic polymer foam board of claim 52 , wherein the alkenyl aromatic polymer foam board is dimensionally stable.
59. A process for making an alkenyl aromatic polymer foam board comprising:
melting a thermoplastic alkenyl aromatic polymer;
dissolving an effective amount of a blowing agent blend in the alkenyl aromatic polymer to define a mixture, the blowing agent blend consisting of methyl formate and carbon dioxide, and optionally water;
forming an extrudate from the mixture; and
expanding the extrudate to produce the alkenyl aromatic polymer foam board, wherein the alkenyl aromatic polymer foam board has a thickness of at least 0.5 inch and an R value of about 4 per inch or greater, and wherein the blowing agent blend is the sole blowing agent in the polymer.
60. The alkenyl aromatic polymer foam board of claim 52 , further comprising mixing a nucleating agent with the alkenyl aromatic polymer prior to the extrudate forming step.
61. A process for making an alkenyl aromatic polymer foam board comprising:
melting a thermoplastic alkenyl aromatic polymer;
dissolving an effective amount of a blowing agent blend in the alkenyl aromatic polymer to define a mixture, the blowing agent blend consisting of methyl formate and carbon dioxide, and optionally water;
forming an extrudate from the mixture; and
expanding the extrudate to produce the alkenyl aromatic polymer foam board, wherein the alkenyl aromatic polymer foam board has a thickness of at least 0.5 inch and an R value of about 4 per inch or greater, and wherein the blowing agent blend is the sole blowing agent in the polymer.
62. The process of claim 61 , wherein the average cell size of the alkenyl aromatic polymer foam board is about 160 to about 285 microns.
63. The process of claim 61 , wherein the extrudate comprises from about 1 to about 18 weight percent blowing agent.
64. The process of claim 61 , wherein the alkenyl aromatic polymer is polystyrene.
65. The process of claim 61 , wherein the alkenyl aromatic polymer foam board is dimensionally stable.