US5281632A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Cellular polymer containing perforated cell windows and a process for the preparation thereof
Assignee: Dow Chemical Co
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Filing: 1993-06-22
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Granted: 1994-01-25
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Expires: 2013-06-22
Abstract
Abstract A process for preparing a cellular polymer containing perforated cell windows in the presence of a perforating agent being a substance that has a critical surface free energy of less than about 23 mJ/m2 is disclosed. The cellular polymers obtained according to this invention have a fine cell structure and show enhanced dimensional and thermal insulation stability. The invention also relates to rigid polyurethane foam prepared in the presence of, for example, particulate poly(tetrafluoroethylene) or a liquid polyfluoro- or perfluorocarbon, with a boiling point of at least 130 degrees C., as perforating agent.
Inventors
- 👤 Guido F. Smits
- 👤 Johan A. Thoen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 19:33
CPC Classifications
C; C08; C08J; C08J9/00; C08J9/0061; C08J9/0014; C08J9/0019; C08J2205/00; C08J2205/04; C08J2205/05; C08J2323/00; C08J2323/02; C08J2323/04; C08J2323/06; C08J2325/00; C08J2325/02; C08J2325/04; C08J2325/06; C08J2361/00; C08J2361/04; C08J2361/06; C08J2367/00; C08J2367/02; C08J2371/00; C08J2375/00; C08J2375/04; C08J2377/00; C08J2427/00; C08J2427/02; C08J2427/12; C08J2427/18; Y; Y10; Y10S; Y10S521/00; Y10S521/908
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
85 words
A foamable polyurethane precursor composition comprising a polyurethane precursor, being a polyisocyanate or a substance containing a isocyanate-reactive hydrogen atoms, and a perforating agent characterized in that the perforating agent is present in from about 0.01 to about 2.0 percent based on total weight of precursor and agent present, and is a liquid polyfluorinated substance that has a critical surface free energy of less about 23 mJ/m 2 and having a boiling point greater than 130° C. and a molecular weight of at least 350.
Claim 2
Dependent Claim
85 words
A foamable polyurethane precursor composition comprising a polyurethane precursor, being a polyisocyanate or a substance containing a isocyanate-reactive hydrogen atoms, and a perforating agent characterized in that the perforating agent is present in from about 0.01 to about 2.0 percent based on total weight of precursor and agent present, and is a liquid polyfluorinated substance that has a critical surface free energy of less about 23 mJ/m 2 and having a boiling point greater than 130° C. and a molecular weight of at least 350.
Claim 3
Dependent Claim
17 words
The polyurethane precursor composition of claim 1 wherein said liquid perforating agent is a polyfluoro-or perfluorocarbon compound.
Claim 4
Dependent Claim
14 words
The polyurethane precursor composition of claim 1 where the precursor is an organic polyisocyanate.
Claim 5
Dependent Claim
26 words
The polyurethane precursor composition of claim 2 where the precursor substance containing isocyanate-reactive hydrogen atoms is a polyether polyol, polyester polyol, amine-terminated polyether or mixtures thereof.
Claim 6
Dependent Claim
136 words
A cellular polyurethane polymer containing perforated cell windows and which has a density of from about 10 to about 150 kg/m 3 prepared by reacting an organic polyisocyanate with a substance containing one or more isocyanate-reactive hydrogen atoms/molecule in the presence of a blowing agent and a perforating agent which has a critical surface free energy of less than 23 mJ/m 2 characterized in that: a) the blowing agent comprises water in an amount to provide for at least 50 mole percent of the blowing requirement; and b) the perforating agent is a liquid polyfluorocarbon or perfluorocarbon, with a boiling point at atmospheric pressure of at least 130° C. and a molecular weight of at least 350 and is present in from about 0.01 to about 0.6 percent based on total weight of the polyurethane polymer.
Claim 7
Dependent Claim
136 words
A cellular polyurethane polymer containing perforated cell windows and which has a density of from about 10 to about 150 kg/m 3 prepared by reacting an organic polyisocyanate with a substance containing one or more isocyanate-reactive hydrogen atoms/molecule in the presence of a blowing agent and a perforating agent which has a critical surface free energy of less than 23 mJ/m 2 characterized in that: a) the blowing agent comprises water in an amount to provide for at least 50 mole percent of the blowing requirement; and b) the perforating agent is a liquid polyfluorocarbon or perfluorocarbon, with a boiling point at atmospheric pressure of at least 130° C. and a molecular weight of at least 350 and is present in from about 0.01 to about 0.6 percent based on total weight of the polyurethane polymer.
Claim 8
Dependent Claim
30 words
The polyurethane precursor composition of claim 1 wherein the polyfluorinated substance has a boiling point of at least 175° C. and is insoluble or only sparingly soluble in the precursor.
Claim 9
Dependent Claim
19 words
The polyurethane precursor composition of claim 6 wherein the polyfluorinated substance is a mixture of C 15-18 perfluorinated compounds.
Claim 10
Dependent Claim
13 words
The polyurethane precursor composition of claim 3 wherein the polyisocyanate is toluene diisocyanate.
Claim 11
Dependent Claim
15 words
The polyurethane precursor composition of claim 3 wherein the polyisocyanate is a methylene-bridged polyphenyl polyisocyanate.
Claim 12
Dependent Claim
38 words
The polyurethane precursor composition of claim 4 wherein the precursor is a polyether polyol having a hydroxyl equivalent weight of from about 50 to about 700 and containing from about 2 to about 8 hydroxyl groups per molecule.
Claim 13
Dependent Claim
14 words
The polyurethane precursor composition of claim 4 wherein the precursor is a polyester polyol.
Claim 14
Dependent Claim
24 words
The polyurethane precursor composition of claim 11 wherein the polyester polyol has a melting point of from about 50° C. to about 115° C.
Claim 15
Dependent Claim
26 words
The polyurethane precursor composition of claim 4 which further comprises from about 0.5 to about 15 parts water per 100 parts by weight of polyol present.
References Cited (Backward Citations)
US3753933A
Cited
EP0224945A1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1997-01-24 | 1997-07-26 | 1998-01-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-01-24 | 2001-07-26 | 2002-01-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-01-24 | 2005-07-26 | 2006-01-25 | $7700.00 | Window Closed / Lapsed |