US5840774A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Low density microporous polymers and process
Assignee: Research Foundation of the State University of New York
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Filing: 1991-02-28
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Granted: 1998-11-24
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Expires: 2011-02-28
Abstract
Abstract The disclosed invention is a crystalline microporous polymer and process for preparing a low density microporous polymer comprising, providing a mixture of a polymer and a polymer solvent, the mixture capable of achieving a supercritical condition; applying pressure, at a temperature sufficient for the mixture to attain a super critical condition; cooling the supercritical solution that results and precipitating a microporous crystalline polymer product.
Inventors
- 👤 Paul Ehrlich
- 👤 Robert Bruce Stewart
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 12:24
CPC Classifications
C; C08; C08J; C08J9/00; C08J9/28; C08J2201/00; C08J2201/02; C08J2201/032; C08J2201/04; C08J2201/05; C08J2323/00; C08J2323/02; Y; Y02; Y02P; Y02P20/00; Y02P20/50; Y02P20/54
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
66 words
A process for preparing a low density microporous polymer comprising, providing a mixture comprising a crystalline polymer and a polymer solvent, said mixture capable of achieving a supercritical condition; forming a supercritical solution from said mixture by applying pressure at a temperature sufficient for said mixture to attain a supercritical condition; cooling the supercritical solution at a rate sufficient to precipitate a porous crystalline polymer product.
Claim 2
Dependent Claim
66 words
A process for preparing a low density microporous polymer comprising, providing a mixture comprising a crystalline polymer and a polymer solvent, said mixture capable of achieving a supercritical condition; forming a supercritical solution from said mixture by applying pressure at a temperature sufficient for said mixture to attain a supercritical condition; cooling the supercritical solution at a rate sufficient to precipitate a porous crystalline polymer product.
Claim 3
Dependent Claim
18 words
The process of claim 1 wherein said mixture comprises from about 2 to about 50 weight percent polymer.
Claim 4
Dependent Claim
22 words
The process of claim 1 wherein said mixture comprises a solvent in a gaseous state and a polymer in a solid state.
Claim 5
Dependent Claim
14 words
The process of claim 1 wherein heat is applied to attain said supercritical condition.
Claim 6
Dependent Claim
12 words
The process of claim 1 wherein said polymer comprises an olefin polymer.
Claim 7
Dependent Claim
19 words
The process of claim 5 wherein said polymer is selected from the group consisting of polyethylene, polypropylene and polybutylene.
Claim 8
Dependent Claim
24 words
The process of claim 6 wherein said polymer is selected from the group consisting of linear polyethylene, branched polyethylene, poly-4 methylpentene-1 and isotactic polypropylene.
Claim 9
Dependent Claim
11 words
The process of claim 1 wherein said mixture comprises a copolymer.
Claim 10
Dependent Claim
30 words
The process of claim 8 wherein said copolymer is formed from an olefin and one of the group consisting of vinyl acetate, vinyl chloride, vinyl fluoride, chlorotrifluoroethylene and acrylic acid.
Claim 11
Dependent Claim
19 words
The process of claim 1 wherein said solvent has a critical temperature from about 5° to about 250° Centigrade.
Claim 12
Dependent Claim
24 words
The process of claim 10 wherein said solvent comprises one of the group consisting of carbon dioxide, lower alkane, lower alkene and lower halocarbon.
Claim 13
Dependent Claim
12 words
The process of claim 11 wherein said solvent comprises a lower alkane.
Claim 14
Dependent Claim
18 words
The process of claim 12 wherein said solvent is selected from the group consisting of propane and butane.
Claim 15
Dependent Claim
17 words
The process of claim 1 wherein said pressure is removed after precipitating said porous crystalline polymer product.
Claim 16
Dependent Claim
85 words
A low density microporous polymer produced from a process comprising, providing a mixture comprising a crystalline polymer and a polymer solvent, said mixture capable of achieving a supercritical condition; forming a supercritical solution from said mixture by applying pressure at a temperature sufficient for said mixture to attain a supercritical condition; cooling the supercritical solution at a rate sufficient to precipitate a porous crystalline polymer product having a network of crystals in an open cell gel configuration, which appear as a collection of lamellar stacks.
Claim 17
Dependent Claim
85 words
A low density microporous polymer produced from a process comprising, providing a mixture comprising a crystalline polymer and a polymer solvent, said mixture capable of achieving a supercritical condition; forming a supercritical solution from said mixture by applying pressure at a temperature sufficient for said mixture to attain a supercritical condition; cooling the supercritical solution at a rate sufficient to precipitate a porous crystalline polymer product having a network of crystals in an open cell gel configuration, which appear as a collection of lamellar stacks.
Claim 18
Dependent Claim
22 words
The product of claim 15 wherein said polymer is selected from the group consisting of substituted and unsubstituted polyethylene, polypropylene and polybutylene.
Claim 19
Dependent Claim
22 words
The product of claim 16 wherein said polymer is selected from the group consisting of linear polyethylene, branched polyethylene and isotactic polypropylene.
Claim 20
Dependent Claim
11 words
The product of claim 15 wherein said mixture comprises a copolymer.
Claim 21
Dependent Claim
30 words
The product of claim 18 wherein said copolymer is formed from an olefin and one of the group consisting of vinyl acetate, vinyl chloride, vinyl fluoride, chlorotrifluoroethylene and acrylic acid.
Claim 22
Dependent Claim
24 words
The product of claim 15 wherein said solvent comprises one of the group consisting of carbon dioxide, lower alkane, lower alkene and lower halocarbon.
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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) | 2001-11-23 | 2002-05-25 | 2002-11-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-11-23 | 2006-05-25 | 2006-11-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-11-23 | 2010-05-25 | 2010-11-24 | $7700.00 | Window Closed / Lapsed |