US3664938A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrical coalescence of polymer fines
Assignee: Dow Chemical Co
•
Filing: 1970-01-05
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Granted: 1972-05-23
•
Expires: 1990-01-05
Abstract
Abstract Polymer fines suspended in the organic phase recovered from the polymerization of a suspension of aqueous water-soluble monomer in an organic liquid are precipitated by deposition or agglomeration by the application of an electrical field. The process is particularly applicable to the purification for recycle of an organic medium such as xylene in the inverse suspension polymerization of acrylamide.
Inventors
- 👤 Edward J Thomas
- 👤 Ralph E Friedrich
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 22:29
CPC Classifications
C; C08; C08F; C08F2/00; C08F2/58; B; B01; B01D; B01D21/00; B01D21/0009; B01J; B01J2/00; C08F6/00; C08F6/14; C08F6/22; C08J; C08J3/00; C08J3/12; C08J3/16
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
10 words
The process of claim 1 wherein the polymer is polyacrylamide.
Claim 2
Dependent Claim
13 words
The process of claim 2 wherein the liquid organic dispersion medium is xylene.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-05-23 | 1975-11-22 | 1976-05-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-05-23 | 1979-11-22 | 1980-05-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-05-23 | 1983-11-22 | 1984-05-23 | $7700.00 | Window Closed / Lapsed |