US3920587A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Open-cell rigid polyether polyurethane foam
Assignee: Union Carbide Corp
•
Filing: 1973-11-21
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Granted: 1975-11-18
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Expires: 1993-11-21
Abstract
Abstract Process for the production of open-cell rigid polyether polyurethane foam employing as the cell-opening agent a siloxaneoxyalkylene (AB)n block copolymer and the cured foams produced thereby.
Inventors
- 👤 John Watkinson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 11:24
CPC Classifications
C; C08; C08J; C08J9/00; C08J9/0061; C08G; C08G18/00; C08G18/06; C08G18/28; C08G18/40; C08G18/48; C08G2110/00; C08G2110/0025; C08G2110/0041; C08G2110/005; C08G2350/00; C08J2375/00; C08J2375/04; C08J2375/08; C08J2483/00; Y; Y10; Y10S; Y10S521/00; Y10S521/908
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
138 words
A PROCESS FOR PRODUCING AN OPEN-CELL RIGID POLYETHER POLYURETHANE FOAM HAVING A CLOSED CONTENT OF LESS THAN 50 PER CENT WHICH COMPRISES FOAMING AND CURING A REACTION MIXTURE COMPRISING: A. A POLYETHER POLYCOL HAVING AN AVERAGE MOLECULAR WEIGHT OF ABOUT 200 TO ABOUT 1500 AND A HYDROXYL NUMBER OF ABOUT 200 TO ABOUT 1000; B. AN ORGANIC POLYISOCYANATE, SAID ESTER AND POLYISOCYANATE, TAKEN TOGETHER, BEGIN PRESENT IN THE MIXTURE IN A MAJOR AMOUNT AND IN THE RELATIVE AMOUNT REQUIRED TO PRODUCE THE POLYURETHANE; C. A BLOWING AGENT IN A MINOR AMOUNT SUFFICIENT TO FOAM THE REACTION MIXTURE; D. A CATALYTIC AMOUNT OF A CATALYST FOR THE PRODUCTION OF THE POLYUKRETHANE FROM THE POLYETHER AND THE POLYISOCYANATE; AND E. AS THE CELL-OPENING AGENT A MINOR AMOUNT OF AN ESSENTIALLY LINEAR NON-HYDROLYZABLE SILOXANE-OXYALKYLENE (AB)" BLOCK COPOLYMER HAVING THE AVERAGE FORMULA:
Claim 2
Dependent Claim
138 words
A PROCESS FOR PRODUCING AN OPEN-CELL RIGID POLYETHER POLYURETHANE FOAM HAVING A CLOSED CONTENT OF LESS THAN 50 PER CENT WHICH COMPRISES FOAMING AND CURING A REACTION MIXTURE COMPRISING: A. A POLYETHER POLYCOL HAVING AN AVERAGE MOLECULAR WEIGHT OF ABOUT 200 TO ABOUT 1500 AND A HYDROXYL NUMBER OF ABOUT 200 TO ABOUT 1000; B. AN ORGANIC POLYISOCYANATE, SAID ESTER AND POLYISOCYANATE, TAKEN TOGETHER, BEGIN PRESENT IN THE MIXTURE IN A MAJOR AMOUNT AND IN THE RELATIVE AMOUNT REQUIRED TO PRODUCE THE POLYURETHANE; C. A BLOWING AGENT IN A MINOR AMOUNT SUFFICIENT TO FOAM THE REACTION MIXTURE; D. A CATALYTIC AMOUNT OF A CATALYST FOR THE PRODUCTION OF THE POLYUKRETHANE FROM THE POLYETHER AND THE POLYISOCYANATE; AND E. AS THE CELL-OPENING AGENT A MINOR AMOUNT OF AN ESSENTIALLY LINEAR NON-HYDROLYZABLE SILOXANE-OXYALKYLENE (AB)" BLOCK COPOLYMER HAVING THE AVERAGE FORMULA:
Claim 3
Dependent Claim
33 words
A process as defined in claim 1, wherein the siloxane-oxyalkylene block copolymer has an average molecular weight of at least about 35,000 up to about 60,000 and where R represents a methyl radical.
Claim 4
Dependent Claim
100 words
A process as defined in claim 2, wherein (CnH2nO) represents a mixture consisting of about 30 to 75 weight per cent of oxyethylene groups and about 70 to 25 weight per cent of oxypropylene groups; wherein the siloxane blocks constitute about 25 to about 50 weight per cent of the copolymer and the polyoxyalkylene blocks constitute about 75 to about 50 weight per cent of the copolymer; and wherein the average molecular weight of each siloxane block ranges from about 500 to about 5000 and the average molecular weight of each polyoxyalkylene block ranges from about 1,000 to about 5,000.
Claim 5
Dependent Claim
98 words
A process as defined in claim 2, wherein in the siloxane blocks constitute about 30 to about 45 weight per cent of the copolymer and the polyoxyalkylene blocks constitute about 70 to about 55 weight per cent of the copolymer; wherein the average molecular weight of each siloxane block raNges from about 1000 to about 3,500 and wherein the average molecular weight of each polyoxyalkylene block ranges from about 2000 to about 3,500; and wherein (CnH2nO) represents a mixture constituting of about 50 weight per cent of oxyethylene groups and about 50 weight per cent of oxypropylene groups.
Claim 6
Dependent Claim
32 words
A process as defined in claim 2, wherein the polyether polyol has an average molecular weight of about 250 to about 800 and a hydroxyl number of about 300 to about 600.
Claim 7
Dependent Claim
15 words
A process as defined in claim 5, wherein the organic polyisocyanate is a poly(phenylmethane) polyisocyanate.
Claim 8
Dependent Claim
21 words
A process as defined in claim 5 wherein the polyether polyol comprises a mixture of two or more different polyether polyols.
Claim 9
Dependent Claim
22 words
A process as defined in claim 5 wherein the blowing agent is selected from the group consisting of water and haloflurocarbon compounds.
Claim 10
Dependent Claim
13 words
A process as defined in claim 8 wherein the blowing agent is trichlorofluoroethane.
Claim 11
Dependent Claim
25 words
A process as defined in claim 7 wherein the catalyst is selected from the group consisting of tertiary amine compounds, organo-tin compounds, and mixtures thereof.
Claim 12
Dependent Claim
22 words
A process as defined in claim 10, wherein the catalyst is a mixture of a tertiary amine compound and an organo-tin compound.
Claim 13
Dependent Claim
32 words
A process as defined in claim 2, wherein the siloxane-oxyalkylene (AB)n copolymer cell-opening agent employed is sufficient to provide the polyurethane foam with a closed-cell content of less than 20 per cent.
Claim 14
Dependent Claim
19 words
A process as defined in claim 12 which comprises foaming and curing the reaction mixture with a single step.
Claim 15
Dependent Claim
19 words
A process as defined in claim 5, wherein the reaction mixture contains a flame retardant as an additional ingredient.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-11-17 | 1979-05-19 | 1979-11-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-11-17 | 1983-05-19 | 1983-11-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-11-17 | 1987-05-19 | 1987-11-18 | $7700.00 | Window Closed / Lapsed |