US4188469A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Composition of hydrophilic fluoropolymers with fibrous matter and liquid carrier
Assignee: EIDP Inc
•
Filing: 1978-04-11
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Granted: 1980-02-12
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Expires: 1998-04-11
Abstract
Abstract Certain fluoropolymers, when chemically modified by reacting them with sulfur or phosphorus containing compounds, become hydrophilic materials useful for making ion-exchange membranes, especially diaphragms for electrolytic cells, particularly chlor-alkali cells used in the production of chlorine, hydrogen and sodium hydroxide from brine.
Inventors
- 👤 James C. Fang
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 22:55
CPC Classifications
C; C25; C25B; C25B13/00; C25B13/04; C08; C08J; C08J5/00; C08J5/20; C08J5/22; C08J5/2206; C08J5/2218; C08J5/2231; C08J5/2243; C08J5/225; C25B13/05; C25B13/06; C25B13/08; C08J2327/00; C08J2327/02; C08J2327/12
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
112 words
A composition suitable for preparing a diaphragm for a chlor-alkali cell, the composition comprising (a) a hydrophilic fluoropolymer containing nonterminal units represented by the structure ##STR28## where Z is ##STR29## where M is hydrogen, sodium, potassium, lithium, calcium or magnesium; R is an alkyl radical of 1-12 carbon atoms or a cycloalkyl radical of 3-12 carbon atoms; and x is 1, 2, 3, 4 or 5, the hydrophilic fluoropolymer having a sulfur or phosphorus content of about 0.1-10% by weight, not more than about 1% by weight of the fluoropolymer dissolving in water at 20° C.; (b) a fibrous material resistant to attack by the cell liquor; and (c) a liquid carrier.
Claim 2
Dependent Claim
112 words
A composition suitable for preparing a diaphragm for a chlor-alkali cell, the composition comprising (a) a hydrophilic fluoropolymer containing nonterminal units represented by the structure ##STR28## where Z is ##STR29## where M is hydrogen, sodium, potassium, lithium, calcium or magnesium; R is an alkyl radical of 1-12 carbon atoms or a cycloalkyl radical of 3-12 carbon atoms; and x is 1, 2, 3, 4 or 5, the hydrophilic fluoropolymer having a sulfur or phosphorus content of about 0.1-10% by weight, not more than about 1% by weight of the fluoropolymer dissolving in water at 20° C.; (b) a fibrous material resistant to attack by the cell liquor; and (c) a liquid carrier.
Claim 3
Dependent Claim
13 words
The composition of claim 1 wherein the fibrous material in (b) is asbestos.
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) | 1983-02-11 | 1983-08-13 | 1984-02-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-02-11 | 1987-08-13 | 1988-02-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-02-11 | 1991-08-13 | 1992-02-12 | $7700.00 | Window Closed / Lapsed |