Claims
- 1. A process for producing halophosphazene polymer which comprises (i) heating a nitrogen source with a stoichiometric excess of a phosphorous source so that hydrogen halide is evolved and halophosphazene is formed, said helophosphazene having the formula
- [X--(PX.sub.2 .dbd.N).sub.n --PX.sub.3 ].sup.+ PX.sub.6.sup.-
- wherein n is a numeral which averages at least 3 and X is halogen, and (ii) heating at least a portion of the halophosphazene with at least a stoichiometric amount of nitrogen source so that hydrogen halide is evolved and substantially linear halophosphazene phazene polymer of higher molecular weight is formed.
- 2. A process of claim 1 wherein in (ii) a stoichiometic excess of the nitrogen source is employed.
- 3. A process of claim 1 wherein (i) is conducted in a liquid inert reaction medium.
- 4. A process of claim 3 wherein said medium is at least predominantly a halohydrocarbon.
- 5. A process of claim 3 wherein said medium is at least predominantly a nitroaromatic hydrocarbon.
- 6. A process of claim 3 wherein in (i) the mole ratio of phosphorus source:nitrogen source is in the range of above 1:1 to about 3:1.
- 7. A process of claim 6 wherein said mole ratio is in the range of from 1.1:1 to 1.5:1.
- 8. A process of claim 3 wherein in (i) the temperature falls within the range of from about 50.degree. C. to about 200.degree. C.
- 9. A process of claim 8 wherein said temperature falls within the range of from about 70.degree. C. to about 150.degree. C.
- 10. A process of claim 3 wherein at least a portion of (ii) is conducted in bulk.
- 11. A process of claim 3 wherein a first portion of (ii) is conducted in bulk and wherein a subsequent portion of (ii) is conducted in a liquid inert solvent.
- 12. A process of claim 11 wherein the solvent employed in (ii) is at least predominantly an aromatic hydrocarbon, a cycloaliphatic hydrocarbon, a halogenated hydrocarbon, or any mixture thereof.
- 13. A process of claim 3 wherein (ii) is performed in a liquid inert solvent.
- 14. A process of claim 13 wherein the solvent employed in (ii) is at least predominantly an aromatic hydrocarbon, a cycloaliphatic hydrocarbon, a halogenated hydrocarbon, or any mixture thereof.
- 15. A process of claim 13 wherein at least a portion of (ii) is conducted at superatmospheric pressure and hydrogen halide is continuously or periodically bled from the reaction system.
- 16. A process of claim 3 wherein (ii) is conducted at a temperature within the range of from about 100.degree. C. to about 350.degree. C.
- 17. A process for producing substantially linear chlorophosphazene polymer which comprises (i) heating a nitrogen source with a stoichiometric excess of a phosphorus source so that hydrogen chloride is evolved and chlorophosphazene is formed, said chlorophosphazene having the formula
- [CL--(CL.sub.2 .dbd.N).sub.n --PCl.sub.3 ].sup.+ PCl.sub.6.sup.-
- wherein n is a numeral which averages at least 3, and (ii) heating at least a portion of the chlorophosphazene with at least a stoichiometric amount of a nitrogen source so that hydrogen chloride is evolved and substantially linear chlorophosphazene polymer of higher molecular weight is formed.
- 18. A process of claim 17 wherein in (i) the nitrogen source is ammonia or ammonium chloride or both, and the phosphorus source is phosphorus pentachloride or the combination of phosphorus trichloride and chlorine or a combination of all three of them.
- 19. A process of claim 17 wherein in (ii) the nitrogen source is ammonia or ammonium chloride.
- 20. A process of claim 17 wherein ammonium chloride is employed as the nitrogen source in at least (ii), the ammonium chloride having a mean particle size below 100 microns.
- 21. A process for producing substantially linear chlorophosphazene polymer which comprises (i) heating a nitrogen source with a stoichiometric excess of a phosphorus source in a liquid inert reaction medium so that hydrogen chloride and chlorophosphazene are formed, said chlorophosphazene having the formula
- [Cl--(PCl.sub.2 .dbd.N).sub.n --PCl.sub.3 ].sup.+ PCl.sub.6.sup.-
- wherein n is a numeral which averages at least 3, and removing hydrogen chloride from the reaction mixture during the reaction; and (ii) heating at least a portion of the chlorophosphazene with an excess of a nitrogen source so that hydrogen chloride and substantially linear chlorophosphazene polymer of higher molecular weight are formed, and removing hydrogen chloride from the reaction mixture during the reaction.
- 22. A process of claim 21 wherein removal of hydrogen chloride during at least a portion of (ii) is effected by sweeping the heated reaction mixture during at least a portion of (ii) with an inert vapor or gas.
- 23. A process of claim 22 wherein in (ii) cyclic chlorophosphazene oligomer is also removed from the reaction mixture along with hydrogen chloride.
- 24. A process of claim 21 wherein removal of hydrogen chloride during at least a portion of (ii) is effected by reducing the pressure on the heated reaction mixture during at least a portion of (ii) to below atmospheric pressure.
- 25. A process of claim 24 wherein in (ii) cyclic chlorophosphazene oligomer is also removed from the reaction mixture along with hydrogen chloride.
- 26. A process of claim 21 wherein removal of hydrogen chloride during at least a portion of (ii) is effected by conducting at least a portion of (ii) in a boiling inert solvent whereby the solvent vapors drive off hydrogen chloride.
- 27. A process of claim 26 wherein in (ii) cyclic chlorophosphazene oligomer is also removed from the reaction mixture along with hydrogen chloride.
- 28. A process of claim 21 wherein in (ii) a stoichiometric excess of the nitrogen source is employed and at least a portion of (ii) is conducted substantially in bulk.
- 29. A process for producing substantially linear halophosphazene polymer which comprises (i) heating a nitrogen source with a stoichiometric excess of a phosphorus source so that hydrogen halide is evolved and halophosphazene is formed, said halophosphazene having the formula
- [X--(PX.sub.2 .dbd.N).sub.n --PX.sub.3 ].sup.+ PX.sub.6.sup.-
- wherein is a numeral which averages at least 3 and X is halogen, (ii) heatIng at least a portion of such halophosphazene with at least a stoichiometric amount of a nitrogen source so that hydrogen halide is evolved and substantially linear halophosphazene Polymer of the higher molecular weight is formed, and (iii) heating at least a portion of such halophosphazene polymer in an inert liquid diluent to increase the molecular weight of the halophosphazene polymer so formed.
- 30. A process of claim 29 wherein hydrogen halide is removed from the reaction mixture either continuously or periodically during at least a portion of (ii) and during at least a portion of (iii).
- 31. A process of claim 29 wherein (ii) and (iii) are conducted on a substantially continual basis.
- 32. A process of claim 29 wherein at least a portion of (ii) is conducted substantially in bulk and wherein said diluent in (iii) is at least predominantly an aromatic hydrocarbon, a cycloaliphatic hydrocarbon, a halogenated hydrocarbon, or any mixture thereof.
- 33. A process of claim 29 wherein the phosphorus source in (i) is phosphorus pentachloride or a combination of phosphorus trichloride and chlorine or a combination of all three of them, wherein the nitrogen source in (i) and (ii) is ammonia or ammonium chloride or both of them, and wherein hydrogen chloride formed in (i), (ii) and (iii) is removed from the reaction mixtures thereof.
- 34. A process of claim 33 wherein the nitrogen source at least in (ii) is ammonium chloride having a mean particle size below about 100 microns.
- 35. A process of claim 29 wherein at least a portion of (iii) is conducted at superatmospheric pressure and hydrogen halide is continuously or periodically bled from the reaction system.
- 36. A process of claim 29 wherein (iii) is conducted at a temperature within the range of from about 100.degree. C. to about 350.degree. C.
- 37. A process of claim 1 wherein (i) and (ii) are conducted on a substantially continual basis by introducing at least a portion of the nitrogen source material for (ii) into the reaction mixture from (i) so that the reaction mixture contains at least a stoichiometric amount of the nitrogen source material relative to the halophosphazene from (i).
REFERENCE TO RELATED APPLICATIONS
This is a continuation-in part of my copending application, Ser. No. 447,720, filed Dec. 7, 1982,now U.S. Pat No. 4,447,408, which in turn is a continuation-in-part of my still earlier application, Ser. No. 314,522, filed Oct. 26, 1981, now U.S. Pat. No. 4,374,815, issued Feb. 22, 1983.
US Referenced Citations (5)
Non-Patent Literature Citations (1)
Entry |
Lund et al., J. Chem. Soc. (1960), 2542-2547. |
Continuation in Parts (2)
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Number |
Date |
Country |
Parent |
447720 |
Dec 1982 |
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Parent |
314522 |
Oct 1981 |
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