US4358587A
Expired / Lapsed
US
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Water-soluble cellulose mixed ethers which contain a phosphonomethyl substituent and a process for preparing same
Assignee: Hoechst AG
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Filing: 1981-10-20
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Granted: 1982-11-09
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Expires: 2001-10-20
Abstract
Abstract Disclosed are water-soluble cellulose mixed ethers which contain (a) at least one substituent from the group comprising alkyl, hydroxyalkyl, carboxyalkyl, sulfoalkyl and dialkylaminoalkyl and (b) a phosphonomethyl substituent and which has a DS of the first substituent(s) other than hydroxyalkyl from about 0.05 to 2.95 and/or an MS HAlk from about 0.5 to 6 and a DS PM from about 0.005 to 0.8. Also disclosed is a process for preparing such cellulose mixed ethers in which, per mole of the cellulose, from about 0.1 to 25 moles of the etherifying agent(s) for producing the substituent(s) under (a), from about 0.05 to 2 moles of halogenomethane phosphonate ions as the etherifying agent for producing the substituent under (b) and from about 0.8 to 12 moles of hydroxide ions are caused to react in a reaction mixture comprising up to about 30 parts by weight, per part by weight of the cellulose, of a mixture which is composed of an inert, preferably water-miscible organic solvent and H 2 O and in which the proportion of water ranges from about 3 to 40 percent by weight.
Inventors
- 👤 Lothar Brandt
- 👤 Arno Holst
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 16:07
CPC Classifications
C; C08; C08B; C08B11/00; C08B11/193
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
67 words
A water-soluble cellulose mixed ether, comprising: a substituted cellulose material having at least one first substituent selected from alkyl, hydroxyalkyl, carboxyalkyl, sulfoalkyl, or dialkylaminoalkyl, and a phosphonomethyl substituent, and having a DS of said first substituents, excluding hydroxyalkyl, from about 0.05 to 2.95 and/or an MS HAlk of from about 0.5 to 6 and a DS PM of said phosphonomethyl substituent of from about 0.005 to 0.8.
Claim 2
Dependent Claim
67 words
A water-soluble cellulose mixed ether, comprising: a substituted cellulose material having at least one first substituent selected from alkyl, hydroxyalkyl, carboxyalkyl, sulfoalkyl, or dialkylaminoalkyl, and a phosphonomethyl substituent, and having a DS of said first substituents, excluding hydroxyalkyl, from about 0.05 to 2.95 and/or an MS HAlk of from about 0.5 to 6 and a DS PM of said phosphonomethyl substituent of from about 0.005 to 0.8.
Claim 3
Dependent Claim
20 words
A cellulose mixed ether as defined in claim 1, wherein said first substituent comprises methyl, ethyl, hydroxyethyl, hydroxypropyl or carboxymethyl.
Claim 4
Dependent Claim
40 words
A cellulose mixed ether as defined in claim 2, wherein said first substituent comprises hydroxy ethyl having an MS HE of from about 0.8 to 5 and said phosphonomethyl substituent has a DS PM of from about 0.01 to 0.6.
Claim 5
Dependent Claim
39 words
A cellulose mixed ether as defined in claim 2, wherein said first substituent comprises carboxymethyl having a DS CM of from about 0.2 to 1.5 and said phosphonomethyl substituent has a DS PM of from about 0.01 to 0.6.
Claim 6
Dependent Claim
118 words
A process for preparing a water-soluble cellulose mixed ether as defined by claim 1, comprising the step of: reacting cellulose or a derivative thereof with from about 0.1 to 25 moles of a first etherifying agent for producing said first substituent, from about 0.05 to 2 moles of a second etherifying agent comprising halogenomethane phosphonate ions for producing said phosphonomethyl substituent; and from about 0.8 to 12 moles of hydroxide ions as an alkalizing agent, on a per mole of cellulose basis, in a reaction mixture comprising up to about 30 parts by weight, per part by weight of cellulose, of a mixture including from about 3 to 40% by weight of water and an inert organic solvent.
Claim 7
Dependent Claim
13 words
A process as defined in claim 5, wherein said organic solvent is water-miscible.
Claim 8
Dependent Claim
105 words
A process as defined in claim 5, comprising reacting cellulose or a derivative thereof with from about 0.3 to 8 moles of said first etherifying agent for producing said first substituent; from about 0.1 to 1 moles of said halogenomethane phosphonate ions for producing said phosphonomethyl substituent; and from about 1 to 6 moles of hydroxide ions as an alkalizing agent on a per mole of cellulose basis, and wherein said reaction mixture comprises from about 5 to 15 parts by weight, per part by weight of cellulose, of said second mixture including 10 to 30% by weight of water and said inert organic solvent.
Claim 9
Dependent Claim
13 words
A process as defined in claim 5, wherein said organic solvent comprises isopropanol.
Claim 10
Dependent Claim
51 words
A process as defined in claim 5, wherein said first etherifying agent for producing said first substituent comprises methyl chloride, ethyl chloride, ethylene oxide, propylene oxide or monochloroacetic acid or a salt thereof, and said second etherifying agent for producing said phosphonomethyl substituent comprises chloromethane phosphonic acid or a salt thereof.
Claim 11
Dependent Claim
15 words
A process as defined in claim 1, wherein said first etherifying agent comprises ethylene oxide.
Claim 12
Dependent Claim
15 words
A process as defined in claim 10, wherein said first etherifying agent comprises monochloroacetic acid.
Claim 13
Dependent Claim
50 words
A process as defined in claim 5, wherein said reacting step comprises the separate steps of alkalizing said cellulose with said alkalizing agent to produce an alkali cellulose intermediate and thereafter etherifying the intermediate in etherification steps with said first and second etherifying agents to produce the cellulose mixed ether.
Claim 14
Dependent Claim
24 words
A process as defined in claim 12, wherein said alkalizing agent and said first and second etherifying agents are introduced to said reaction simultaneously.
Claim 15
Dependent Claim
24 words
A process as defined in claim 12, wherein said first and second etherifying agents are introduced in said reaction subsequent to said alkalizing agent.
Claim 16
Dependent Claim
21 words
A process as defined in claim 5, wherein said reaction is carried out at a temperature up to about 100° C.
Claim 17
Dependent Claim
31 words
A process as defined in claim 12, wherein the alkalizing step occurs at room temperature and the first and second etherifying steps occur at a temperature up to about 100° C.
Claim 18
Dependent Claim
27 words
A process as defined in claim 5, wherein said hydroxide ions are provided by an alkali metal hydroxide selected from sodium hydroxide, potassium hydroxide or lithium hydroxide.
Claim 19
Dependent Claim
15 words
A process as defined in claim 17, wherein said alkali metal hydroxide comprises sodium hydroxide.
Claim 20
Dependent Claim
14 words
A process as defined in claim 5, wherein said cellulose is of natural origin.
Claim 21
Dependent Claim
16 words
A process as defined in claim 18, wherein said alkali metal hydroxide is in regenerated form.
Claim 22
Dependent Claim
18 words
A process as defined in claim 5, wherein the reaction time is from about 0.5 to 8 hours.
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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) | 1985-11-08 | 1986-05-10 | 1986-11-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-11-08 | 1990-05-10 | 1990-11-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-11-08 | 1994-05-10 | 1994-11-09 | $7700.00 | Window Closed / Lapsed |