Patent US4668709A successfully refreshed from Google Patents.
US4668709A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Porous polymers
Assignee: Lever Brothers Co
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Filing: 1986-06-26
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Granted: 1987-05-26
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Expires: 2006-06-26
Abstract
Abstract This invention provides a highly porous crosslinked functionalised polymer having interconnected cavities of micron dimensions and having a pore volume greater than about 5.6 cc/g and having a capacity to absorb water and also to absorb saline solutions. The polymers are generally based on styrene or various acrylates or mixtures and have a functional group selected from a large range of ionic and polar compositions.
Inventors
- 👤 Keith Jones
- 👤 Barry R. Lothian
- 👤 Alexander Martin
- 👤 Graham Taylor
- 👤 Ziq Hao
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 07:40
CPC Classifications
B; B01; B01J; B01J20/00; B01J20/22; B01J20/26; C; C08; C08J; C08J9/00; C08J9/28; C08J2201/00; C08J2201/04; C08J2201/05; C08J2201/0504
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
67 words
A porous, homogeneous, cross-linked polymeric material having interconnected cavities or chambers of micron dimensions whose total pore volume is greater than 95% (20 cc/g), said material formed from a water-in-oil emulsion, said emulsion containing at least 95% by weight water, the material having a dry density of less than 0.15 g/cc and comprising at least 30% by weight of chloromethyl styrene residues crosslinked with a di-functional agent.
Claim 2
Dependent Claim
67 words
A porous, homogeneous, cross-linked polymeric material having interconnected cavities or chambers of micron dimensions whose total pore volume is greater than 95% (20 cc/g), said material formed from a water-in-oil emulsion, said emulsion containing at least 95% by weight water, the material having a dry density of less than 0.15 g/cc and comprising at least 30% by weight of chloromethyl styrene residues crosslinked with a di-functional agent.
Claim 3
Dependent Claim
22 words
A polymeric material according to claim 1 wherein said emulsion further comprises a surfactant in an amount greater than 20% by weight.
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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) | 1990-05-25 | 1990-11-24 | 1991-05-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-05-25 | 1994-11-24 | 1995-05-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-05-25 | 1998-11-24 | 1999-05-26 | $7700.00 | Window Closed / Lapsed |