US3676476A
Expired / Lapsed
US
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A method for preparing trivalent and pentavalent antimony esters of polyhydroxy compounds
Assignee: EIDP Inc
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Filing: 1970-11-30
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Granted: 1972-07-11
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Expires: 1990-11-30
Abstract
Abstract A method for the preparation of esters of pentavalent antimony and mixed esters of trivalent antimony and pentavalent antimony with polyhydroxy compounds having vicinal hydroxy groups in solutions of the polyhydroxy compounds or other polar organic solvents, which comprises (1) oxidizing antimony trioxide with aqueous nitric acid in presence of hydrochloric acid to provide pentavalent antimony oxide and hydroxide or mixed trivalent and pentavalent antimony oxides and hydroxides, (2) adding the oxides and hydroxides to an excess of the polyhydroxy compound and heating to cause the components to react while simultaneously distilling under reduced pressure to remove water of reaction, and optionally (3) removing the bulk of the excess unreacted polyhydroxy compound by continued distillation to form a slurry of the ester or mixed esters in the remaining polyhydroxy compound, and either recovering the crystallized pentavalent antimony ester or dissolving the slurry in another polar organic solvent. The solutions are used to incorporate antimony into organic polymers to provide flame resistance.
Inventors
- 👤 Michael J Randolph
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 13:21
CPC Classifications
C; C07; C07F; C07F9/00; C07F9/90; C07F9/902; C08; C08K; C08K5/00; C08K5/59
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
30 words
Method of claim 1 wherein water liberated in reaction between the oxides or hydroxides and the polyhydroxy compound is removed continuously by distillation under reduced pressure as the reaction proceeds.
Claim 2
Dependent Claim
11 words
Method of claim 2 wherein the polyhydroxy compound is ethylene glycol.
Claim 3
Dependent Claim
103 words
Method of claim 2 comprising the further steps of removing the bulk of the excess unreacted polyhydroxy compound by distillation under reduced pressure to form a slurry of the pentavalent antimony ester or a solution containing the mixed esters in the remaining unreacted polyhydroxy compound, then adding to the slurry or solution a polar organic solvent characterized by a dielectric constant measured at 25* C. and 104 to 105 cycles per second which exceeds 35 electrostatic units and ratio of carbon atoms to heteroatoms less than 1.7, whereby there is formed a clear solution of said ester or mixed esters in said solvent.
Claim 4
Dependent Claim
28 words
Method of claim 4 wherein the solvent is selected from the group consisting of formic acid, formamide, methylformamide, dimethylformamide, acetamide, 1,3-propanediol, ethylene glycol, diethylene glycol, glycerol, and dimethylsulfoxide.
Claim 5
Dependent Claim
18 words
Method of claim 4 wherein the polyhydroxy compound is ethylene glycol and the solvent is dimethylformamide or dimethylsulfoxide.
Claim 6
Dependent Claim
71 words
Method of claim 2 wherein the oxidation is carried out at 25* to 122* C., the weight ratio of nitric acid to hydrochloric acid, calculated as 70 percent nitric acid and 37 percent hydrochloric acid, is in the range of 2:1 to 200:1, the mol ratio of nitric acid to antimony trioxide is at least 4:1, and the reaction with the polyhydroxy compound is carried out at 150* to 200* C.
Claim 7
Dependent Claim
71 words
Method of claim 4 wherein the oxidation is carried out at 25* to 122* C., the weight ratio of nitric acid to hydrochloric acid, calculated as 70 percent nitric acid and 37 percent hydrochloric acid, is in the range of 2:1 to 200:1, the mol ratio of nitric acid to antimony trioxide is at least 4:1, and the reaction with the polyhydroxy compound is carried out at 150* to 200* C.
Claim 8
Dependent Claim
11 words
Method of claim 8 wherein the polyhydroxy compound is ethylene glycol.
Claim 9
Dependent Claim
11 words
Method of claim 9 wherein the solvent is dimethylformamide or dimethylsulfoxide.
Claim 10
Dependent Claim
77 words
Method of claim 2 wherein sufficient antimony is oxidized to pentavalent state that the mole ratio of pentavalent antimony ester to trivalent antimony ester is greater than 2:1 and comprising the further steps of removing any undissolved solids from the solution by filtration, concentrating the solution by vaporization of the polyhydroxy compound under reduced pressure to give a slurry, then filtering the slurry whereby there is obtained a solid, crystalline pentavalent antimony ester of the polyhydroxy compound.
Claim 11
Dependent Claim
12 words
Method of claim 11 wherein the polyhydroxy compound used is ethylene glycol.
Claim 12
Dependent Claim
77 words
Method of claim 7 wherein sufficient antimony is oxidized to pentavalent state that the mole ratio of pentavalent antimony ester to trivalent antimony ester is greater than 2:1 and comprising the further steps of removing any undissolved solids from the solution by filtration, concentrating the solution by vaporization of the polyhydroxy compound under reduced pressure to give a slurry, then filtering the slurry whereby there is obtained a solid, crystalline pentavalent antimony ester of the polyhydroxy compound.
Claim 13
Dependent Claim
12 words
Method of claim 13 wherein the polyhydroxy compound used is ethylene glycol.
Claim 14
Dependent Claim
69 words
Method of claim 2 wherein the oxidation is carried out at 80* to 110* C., the weight ratio of nitric acid to hydrochloric acid, calculated as 70 percent nitric acid and 37 percent hydrochloric acid, is in the range of 10:1 to 50:1, the mole ratio of nitric acid to antimony trioxide is at least 4:1, and the reaction with the polyhydroxy compound is carried out at 160*-180* C.
Claim 15
Dependent Claim
77 words
Method of claim 15 wherein sufficient antimony is oxidized to pentavalent state that the mole ratio of pentavalent antimony ester to trivalent antimony ester is greater than 2:1 and comprising the further steps of removing any undissolved solids from the solution by filtration, concentrating the solution by vaporization of the polyhydroxy compound under reduced pressure to give a slurry, then filtering the slurry whereby there is obtained a solid, crystalline pentavalent antimony ester of the polyhydroxy compound.
Claim 16
Dependent Claim
30 words
Method of claim 16 wherein the slurry of pentavalent antimony ester is diluted with tetrahydrofuran prior to filtration and after filtration the filtered cake is washed with tetrahydrofuran and dried.
Claim 17
Dependent Claim
11 words
Method of claim 17 wherein the polyhydroxy compound is ethylene glycol.
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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) | 1975-07-11 | 1976-01-10 | 1976-07-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-07-11 | 1980-01-10 | 1980-07-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-07-11 | 1984-01-10 | 1984-07-11 | $7700.00 | Window Closed / Lapsed |