Patent US4891407A successfully refreshed from Google Patents.
US4891407A
Expired / Lapsed
US
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Interpenetrating polymeric networks comprising polytetrafluoroethylene and polysiloxane
Assignee: Donaldson Co Inc
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Filing: 1988-05-20
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Granted: 1990-01-02
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Expires: 2008-05-20
Abstract
Abstract There is provided a composition having interpenetrating matrices comprising (a) a first polymer network characterized by nodes interconnected by fibrils and (b) a second polymer network comprising diorganosiloxy units. In another aspect, there are provided compositions comprising an interpenetrating polymer network of polytetrafluoroethylene and polydiorganosiloxane. Methods for making the foregoing compositions are also provided.
Inventors
- 👤 Tyrone D. Mitchell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 09:59
CPC Classifications
C; C08; C08L; C08L27/00; C08L27/02; C08L27/12; C08L27/18; B; B29; B29C; B29C55/00; B29C55/005; C08L83/00; C08L83/04; B29K; B29K2027/00; B29K2027/12; B29K2027/18; B29K2083/00; C08G; C08G77/00; C08G77/04; C08G77/12; C08G77/20
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
63 words
A method for making a composition capable of being processed into a material having a porous microstructure of interpenetrating matrices in cured form, comprising the steps: (a) dissolving a curable polydiorganosiloxane composition in a solvent, and (b) mixing the solution obtained in (a) with polytetrafluoroethylene powder wherein the weight ratio of said polydiorganosiloxane to said polytetrafluoroethylene powder is from 1:100 to about 20:80.
Claim 2
Independent Claim
63 words
A method for making a composition capable of being processed into a material having a porous microstructure of interpenetrating matrices in cured form, comprising the steps: (a) dissolving a curable polydiorganosiloxane composition in a solvent, and (b) mixing the solution obtained in (a) with polytetrafluoroethylene powder wherein the weight ratio of said polydiorganosiloxane to said polytetrafluoroethylene powder is from 1:100 to about 20:80.
Claim 3
Dependent Claim
15 words
A method as in claim 1, wherein the solvent is kerosene, toluene, or mineral spirits.
Claim 4
Dependent Claim
20 words
A method as in claim 1, wherein mixing is effected in a tumbler-type mixer suitable for mixing liquids with solids.
References Cited (Backward Citations)
US4010136A
Cited
US4544692A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-01-01 | 1993-07-03 | 1994-01-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-01-01 | 1997-07-03 | 1998-01-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-01-01 | 2001-07-03 | 2002-01-02 | $7700.00 | Window Closed / Lapsed |