Patent US4329445A successfully refreshed from Google Patents.
US4329445A
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Process for preparing a tetrahydrofuran-alkylene oxide copolymer with treated bentonite catalyst
Assignee: EIDP Inc
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Filing: 1980-05-30
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Granted: 1982-05-11
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Expires: 2000-05-30
Abstract
Abstract A modified montmorillonite clay is prepared by heating it, impregnating it with an organic liquid, acid-activating it with a strong acid, and then washing it with water until it is substantially free of acid anions. The modified clay is useful as a catalyst, particularly for the preparation of tetrahydrofuran/alkylene oxide copolymers.
Inventors
- 👤 Thomas W. Del Pesco
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 19:34
CPC Classifications
C; C08; C08G; C08G65/00; C08G65/02; C08G65/26; C08G65/2642; C08G65/2645; C08G65/2654; C08G65/2657; B; B01; B01J; B01J21/00; B01J21/16; C08G65/04; C08G65/06; C08G65/16; C08G65/20
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
102 words
In a process for catalytically preparing a tetrahydrofuran/alkylene oxide polymer, the improvement comprising using as the catalyst a material prepared by (a) holding a raw granular Wyoming bentonite at a temperature of about 300°-600° C. for about 1-20 hours, in air; (b) impregnating the product of (a) with an organic liquid capable of being intercalated into said product; p1 (c) activating the product of (b) with hydrochloric acid, nitric acid, sulfuric acid or phosphoric acid; (d) removing residual acid from the product of (c); and then (e) washing the product of (d) with water until it is substantially free of acid anions.
Claim 2
Dependent Claim
102 words
In a process for catalytically preparing a tetrahydrofuran/alkylene oxide polymer, the improvement comprising using as the catalyst a material prepared by (a) holding a raw granular Wyoming bentonite at a temperature of about 300°-600° C. for about 1-20 hours, in air; (b) impregnating the product of (a) with an organic liquid capable of being intercalated into said product; p1 (c) activating the product of (b) with hydrochloric acid, nitric acid, sulfuric acid or phosphoric acid; (d) removing residual acid from the product of (c); and then (e) washing the product of (d) with water until it is substantially free of acid anions.
Claim 3
Dependent Claim
12 words
The process of claim 1 wherein the alkylene oxide is ethylene oxide.
Claim 4
Dependent Claim
12 words
The process of claim 1 wherein the alkylene oxide is propylene oxide.
Claim 5
Dependent Claim
20 words
The process of claim 1 in which residual organic liquid from step (b) is removed before step (c) is performed.
Claim 6
Dependent Claim
23 words
The process of claim 1 having the additional step of drying the product of step (e) at a temperature below about 150° C.
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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) | 1985-05-10 | 1985-11-09 | 1986-05-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-05-10 | 1989-11-09 | 1990-05-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-05-10 | 1993-11-09 | 1994-05-11 | $7700.00 | Window Closed / Lapsed |