US4339573A
Expired / Lapsed
US
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Preparation of cellulose derivatives using highly reactive alkali cellulose
Assignee: Henkel AG and Co KGaA
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Filing: 1980-07-07
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Granted: 1982-07-13
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Expires: 2000-07-07
Abstract
Abstract This invention relates to an improved process for preparing cellulose derivatives by alkalizing cellulose to form alkali cellulose, alkylating the alkali cellulose to form alkylated alkali cellulose, and recovering the alkylated alkali cellulose. According to the process of the invention, finely-divided, preferably powdered, cellulose is reacted with an aqueous-alcoholic alkali metal hydroxide solution at a temperature of from about 20 DEG to 120 DEG C., to form alkali cellulose, oxygen is removed, and the water content is reduced to from about 2.5 to 6.0 moles per anhydroglucose unit, prior to alkylization.
Inventors
- 👤 Willi Wust
- 👤 Hasso Leischner
- 👤 Wilfried Rahse
- 👤 Franz-Josef Carduck
- 👤 Norbert Kuhne
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 04:48
CPC Classifications
C; C08; C08B; C08B1/00; C08B1/08
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
89 words
In the process for the preparation of cellulose derivatives by alkalizing finely divided cellulose to form alkali cellulose, alkylating the alkali cellulose to form alkylated alkali cellulose, and recovering the alkylated alkali cellulose, the improvement which comprises reacting said cellulose with an aqueous-alcoholic alkakli metal hydroxide solution at a temperature of from about 20° to 120° C., to form alkali cellulose, removing all of the oxygen therefrom, and reducing the water content to from about 2.5 to 6.0 moles per anhydroglucose unit, prior to alkylation of said alkali cellulose.
Claim 2
Dependent Claim
89 words
In the process for the preparation of cellulose derivatives by alkalizing finely divided cellulose to form alkali cellulose, alkylating the alkali cellulose to form alkylated alkali cellulose, and recovering the alkylated alkali cellulose, the improvement which comprises reacting said cellulose with an aqueous-alcoholic alkakli metal hydroxide solution at a temperature of from about 20° to 120° C., to form alkali cellulose, removing all of the oxygen therefrom, and reducing the water content to from about 2.5 to 6.0 moles per anhydroglucose unit, prior to alkylation of said alkali cellulose.
Claim 3
Dependent Claim
20 words
The process of claim 1, wherein the cellulose is reacted at a temperature of from about 20° to 80° C.
Claim 4
Dependent Claim
22 words
The process of claim 1, wherein powdered cellulose is used which has a mean particle diameter of from about 20 to 120μ.
Claim 5
Dependent Claim
16 words
The process of claim 3, wherein the mean particle diameter is from about 40 to 60μ.
Claim 6
Dependent Claim
22 words
The process of claim 1, wherein primary and/or secondary alkanols with from 1 to 5 carbon atoms, are used in the alkalization.
Claim 7
Dependent Claim
14 words
The process of claim 5, wherein methanol and/or ethanol are used in the alkalization.
Claim 8
Dependent Claim
26 words
The process of claim 1, wherein the alkalization is carried out with molar ratios of alkali metal hydroxide to cellulose of from about 1.5:1 to 5:1.
Claim 9
Dependent Claim
44 words
The process of claim 1, wherein the viscosity of the alkali cellulose is adjusted by time-limited degassing and/or alkaline thermal decomposition in a temperature range of from about 30° to 100° C. and in a pressure range of from 30 torr to normal pressure.
Claim 10
Dependent Claim
16 words
The process of claim 8, wherein the temperature range is from about 40° to 65° C.
Claim 11
Dependent Claim
35 words
The process of claim 1, wherein the alkali metal hydroxide is sodium hydroxide, the etherification agent is methyl chloride, and the molar ratio of methyl chloride to sodium hydroxide is from about 1.0:1 to 1.5:1.
Claim 12
Dependent Claim
21 words
The process of claim 10, wherein the molar ratio of methyl chloride to sodium hydroxide is from about 1.1:1 to 1.3:1.
Claim 13
Dependent Claim
22 words
The process of claim 1, wherein excess water and alcohol are removed in the presence of inert liquids not miscible with water.
Claim 14
Dependent Claim
13 words
The process of claim 12, wherein the inert liquid is toluene or xylene.
Claim 15
Dependent Claim
19 words
The process of claim 1, wherein the process is effected in the presence of inert liquid in continuous operation.
Claim 16
Dependent Claim
35 words
The process of claim 1, wherein alkali cellulose or alkali cellulose partly reacted with monochloroacetic acid or an alkali metal salt thereof is alkylated with methyl chloride, ethylene oxide, propylene oxide, or a mixture thereof.
Claim 17
Dependent Claim
24 words
The process of claim 1, wherein alkali cellulose or partially alkylated alkali cellulose is reacted with chloroacetic acid or an alkali metal salt thereof.
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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) | 1985-07-12 | 1986-01-11 | 1986-07-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-07-12 | 1990-01-11 | 1990-07-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-07-12 | 1994-01-11 | 1994-07-13 | $7700.00 | Window Closed / Lapsed |