Patent US3558722A successfully refreshed from Google Patents.
US3558722A
Expired / Lapsed
US
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Process for the preparation of alpha,omega-dichloropolyalkylene oxides
Assignee: Asahi Kasei Corp
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Filing: 1967-08-03
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Granted: 1971-01-26
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Expires: 1987-08-03
Abstract
Abstract A PROCESS FOR THE PRODUCTION OF HIGH PURITY A,W-DICHLORO-POLYALKYLENE OXIDES HAVING AN AVERAGE MOLECULAR WEIGHT OF FROM 508 TO 5770 FROM TETRAHYDROFURAN OR A MIXTURE THEREOF WITH ONE OTHER CYCLIC ETHER. SAID PROCESS COMPRISES POLYMERIZING SAID CYCLIC ETHER OR ETHERS WITH A BINARY CATALYST CONSISTING OF THIONYL CHLORIDE AND A SPECIFIC LEWIS ACID, SUCH AS ANTIMONY PENTACHLORIDE, STANNIC CHLORIDE, SUCH AS ANTIMONY PENTACHLORIDE, STANNIC CHLORIDE, ETC., THEN REMOVING OR DEACTIVATING SAID LEWIS ACID COMPONENT AND THEREAFTER HEAT-TREATING THE POLYMERIZATION PRODUCT IN THE PRESENCE OF THIONYL CHLORIDE.
Inventors
- 👤 Hidehiko Kobayashi
- 👤 Kiichiro Sasaguri
- 👤 Yoshihisa Fujimoto
- 👤 Jyoji Ibata
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 22:28
CPC Classifications
C; C08; C08G; C08G65/00; C08G65/02; C08G65/04; C08G65/06; C08G65/16; C08G65/20; C08G65/26; C08G65/2642; C08G65/2645; C08G65/30; C08G65/32; C08G65/321; C08G65/326
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-01-25 | 1974-07-27 | 1975-01-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-01-25 | 1978-07-27 | 1979-01-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-01-25 | 1982-07-27 | 1983-01-26 | $7700.00 | Window Closed / Lapsed |