Neorol CHO N=P(C6H5)3 / N1e's N OCEI

3,392,214 United States Patent Office Patented July 9, 1968

2 5 (preferably trimeric) with a phosphorus chloride selected 3,392,214 from the group consisting of phosphorus pentachloride CYCLOTRPHOSPHAZATRENE COMPOUNDS AND PROCESS FOR MAKENG SAME triphenoxy phosphorus dichloride and triphenyl phos Daniel J. Jaszka, Tonawanda, N.Y., assignor to Hooker phorus dichloride, and recovering the resulting product, Chemical Corporation, Niagara Falls, N.Y., a corpora which may thereafter be polymerized to a useful polymer. tion of New York 20 Additionally, the process of this invention includes react No Drawing. Filed Mar. 2, 1964, Ser. No. 348,877 ing diaminocyclophosphazene with phenol to form a 11 Claims. (Cl. 260-927) phenolated diaminocyclophosphazene compound, which may be treated with a phosphorus chloride and This invention relates to cyclophosphazene products, polymerized. including polymers thereof, and to processes for preparing 25 The exact structure of some of the new intermediate them. products and final polymers produced by the processes of The prior art discloses that cyclophosphazene polymers this invention, has not been definitively established. How which have good thermal stability have been made, but ever, it is believed that the following equations con often such polymers are not as hydrolytically stable as is stitute correct representations of the reactions effected desirable. In fact, many such polymers have a very rapid 30 and the products formed according to this invention.

C6H5O NspCl Cl NH2 C.H.0, NH N/ c1 N PCY c1 choir N e's\ oc.H. PO1, N e'\\ oc.H. 300° C. N / m- I/ u-d 1. - Polymer 7's /S KOE (C.H.O.P. /S (C6H5O)2P / N c? SN NH N. NH N, Y=PC, (I) (II) - (III) (IV) Neorol CHO N=P(C6H5)3 / N1e's N OCEI. 400° C. II/ - Polymer (C.H.0), P.n /N N N=P(C6H5)3 (V) (VI) CHO N=P(OCH)3 / (CHO)3P Cls e's --3 N1 Noctl. -m-3 Pol Inler (C.H.0), n K A oly N N=P(OCH)3 (VIII) (VII)

hydrolysis rate. Therefore, it is very desirable to find a Compounds II, III, V, VII, IX, XI, and XIII may be cyclophosphazene derivative which can be reacted to 60 considered cyclotriphosphazatriene of the formula, produce a polymer which has both good thermal stability and enhanced hydrolytic stability. Such products are A. Y useful as materials of construction for formed articles, Y/ such as structural parts, covers, gaskets or plastic con sumer articles subjected to heat and high humidities, and 65 may be employed with other plastics or polymers in molding compositions. Such products are described in this application. In accordance with this invention there is provided wherein A is selected from the group consisting of such a product and a process for preparing it, a cyclo 70 chlorine and phenoxy; and Y is selected from the group phosphazene polymer of increased hydrolytic stability, consisting of -NH2, -NFPCls, -N=P(CHO) and which comprises reacting diaminocyclophosphazene, -NFP(C6H5)3, and A is phenoxy when Y is -NH. 3,392,214 3. Cl N=P Cls / P 2D N PC) Cl N N Cl 300° C. -> N l/ --> Polymer

(IX) (X) N(CH).p Cl N y l N 2 N C N N / - PolyIner P P N / N N (XII)

2 (CoHo). Pol cN N Cl - Polymer P (XIV) It will be convenient in the balance of this specification avoid premature polymerization of the phosphazene to refer to these compounds by the assigned identifying molecule. The monomers are prepared by reacting a Roman numerals. The type of compound shown herein stoichiometric amount or a slight excess of phosphorus is often described as a phosphonitrilic halide derivative. chloride with the desired phosphazene molecule, prefer However, this term is less descriptive than the term 30 ably in a halogenated solvent. The reaction is continued phosphazene, since nitrile implies a under reflux conditions until the cessation of hydrogen chloride evolution. Thereafter, the reaction product is -CN filtered and is freed of solvent by distillation. It is pref bond, whereas the compounds of this invention have no erable that the solvent be distilled under vacuum condi such bonds. Using the phosphazene nomenclature, these 35 tions. Pressures of 5 to 10 millimeters of mercury and compounds are named as follows: lower are satisfactory. To make the intermediate product, compound II, an I. 2,2,4,6-tetrachloro-4,6-diaminocyclotriphosphazatri excess of phenol as an alkali salt thereof is employed ene; to insure complete phenolation of the product. While II. 2,2,4,6-tetraphenoxy-4,6-diaminocyclotriphosphaza 40 it is preferable to use potassium hydroxide to form the triene; phenate, other alkali metal hydroxides, such as sodium III. 2,2,4,6-tetraphenoxy-4,6-di(trichlorophosphazo) hydroxide, are also suitable. The reaction is compelted cyclotriphosphazatriene; when the distillation of water ceases. The reaction mix V. 2,2,4,6-tetraphenoxy-4,6-di(triphenylphosphazo) cy ture is then cooled and neutralized with alkali, such as clotriphosphazatriene; potassium hydroxide, and dried with anhydrous sodium VII. 2,2,4,6-tetraphenoxy-4,6-di(triphenoxyphosphazo)- Sulfate. Thereafter, the solvent is removed by distillation. cyclotriphosphazatriene; The monomers of this invention, compounds III, V, IX. 2,2,4,6-tetrachloro-4,6-di(trichlorophosphazo)cyclo VII, IX, XI and XIII are heated in the absence of oxy triphosphazatriene; gen until polymerized. Preferably the monomers are heat XI. 2,2,4,6-tetrachloro-4,6-di(triphenylphosphazo)cyclo 50 ed at a temperaure from 200 to about 400 degrees centi triphosphazatriene; grade, for a period of about one-half hour to thirty XIII. 2,2,4,6-tetrachloro-4,6-di(triphenoxyphosphazo)- hours. The resulting polymers are characterized by their cyclotriphosphazatriene. excellent hydrolytic stability and heat resisting properties. The diaminohalophosphazene starting material, The invention is illustrated by the following non-lim pound I, is conveniently prepared by aminolysis of cycliccom iting examples. Temperatures are expressed in degrees phosphazene chloride according to the method of De centigrade and parts are by weight unless otherwise indi Ficquelmont, A. M., Ann. chim., 12, 169 (1939). cated. It is desirable to prepaare the monomeric products of Example 1 this invention, compounds III, V, VII, IX, XI and XIII To a reaction vessel containing 344 parts p-xylene and intermediate II in an organic reaction medium. It 60 and equipped with a water-cooled condenser were is preferable in the case of preparation of the aforemen charged 48 parts of the prior art compound (compound tioned monomers to use a chlorinated solvent, such as I), 61 parts of phenol and 53 parts of potassium hydrox monochlorobenzene, trichlorobenzene, orthodichloro ide (85 percent). The mixture was refluxed at about 155 benzene, symmetrical-tetrachloroethane, tetrachloroeth degrees centigrade for about 10 hours, the HCl being ylene, benzyl chloride, chloroform and carbon tetra then removed, after which water was distilled off. After chloride. In addition to the foregoing list of chlorinated the distillation of water had ceased, the reaction mix solvents, compound II may also be satisfactorily pre ture was cooled and was successively treated with 5 per pared from non-halogenated aromatic solvents, such as cent aqueous potassium hydroxide and 5 percent aque paraxylene. While the solvent used may be at least par ous sodium sulfate solution. This treatment produced two tially dependent upon such factors as cost, toxicity and layers of liquid. The water layer was removed and the compatibility with the reaction equipment employed, it Xylene Solution was dried over sodium sulfate and was is preferable that the lower boiling point solvents be distilled at reduced pressure. Forty-two parts of an oily used, i.e., those boiling up to about 150 degrees centi residue were isolated, which residue slowly crystallized. grade, so as to keep the reaction temperature low and 75 Recrystaillization from 95 percent ethanol yielded white 3,392,214 5 6 needle-like crystals having a melting point of 105.5-106 to be stable on exposure to moist atmosphere, retaining degrees centigrade. appreciable elasticity after one month's exposure. For PN(OCH3)4(NH) (II)-Calculated, percent: These and the products of Examples 5-7 are useful Phosphorus, 17.2; carbon, 53.4; hydrogen, 4.5; nitrogen, construction, gasketing and covering materials in ma 13.0. Found, percent: Phosphorus, 17.6; carbon, 53.6; hy chines and articles subjected to high temperatures and drogen, 4.4; nitrogen, 12.7. humidities. Various changes and modifications may be made in the Example 2 method of this invention and in the products thereof. To a reaction vessel containing 135 parts of mono Certain preferred forms have been described but equiva benzene and equipped with water-cooled condenser were 0 lents may be substituted without departing from the spirit charged 46 parts of compound I and 62 parts of phos and scope of this invention. phorus pentachloride. The mixture was refluxed at about What is claimed is: 135 degrees centigrade for about 4 hours, with the evo 1. Cyclotriphosphazatriene of the formula, lution of hydrogen chloride. The reaction mixture was A. Y filtered and the clear liquid was distilled at a reduced 5 Y/ pressure to yield 86 parts of yellow viscous oil consid 1 ered to have the formula of compound IX. A N Y. A Example 3 ) / To a reaction vessel containing 136 parts of mono 20 A? S/ YA chlorobenzene and equipped with a water cooled con wherein A is selected from the group consisting of denser were charged 27 parts of the product of Exam chlorine and phenoxy; and Y is selected from the group ple 1 (II) and 22 parts of phosphorus pentachloride. consisting of -NH2, -N-PCl3, -NFP(C6H5O)3 The mixture was refluxed at about 135 degrees centi and -N=P(C6Hs), and A is phenoxy when Y is grade until the evolution of hydrogen chloride ceased. 25 -NH2. Thereafter, the monochlorobenzene was removed by dis 2. 2,2,4,6 - tetrachloro - 4,6 - di(trichlorophosphazo) tillation at a pressure of about 50 millimeters of mer cyclotriphosphazatriene. cury and 135 degrees centigrade to yield 39 parts of a yel 3. 2,2,4,6 - tetraphenoxy - 4,6 - diaminocyclotriphos low viscous oil considered to have the structure of com phazatriene. pound III. 30 4. 2,2,4,6-tetraphenoxy - 4,6 - di(trichlorophosphazo) Analogous products are obtained when compounds I 'cyclotriphosphazatriene. and II, respectively, are reacted under the same condi 5. 2,2,4,6 - tetraphenoxy - 4,6 - di(triphenylphospha tions with equivalent molar proportions of triphenoxy Zo(cyclotriphosphazatriene. . phosphorus dichloride, (C6H5O)3PCl2, to form com 6. A process for preparing cyclotriphosphazatriene pounds XIII and VII, respectively. Likewise, under the 35 products which comprises reacting at a temperature be same conditions, the reaction of triphenylphosphorusdi low about 150 degrees centigrade 4,6-diaminocyclophos chloride, (C6H5)PCl2 with compounds I and II, respec phazene with a phosphorus chloride selected from the tively, yields compounds XI and V, respectively, as ex group consisting of phosphorus pentachloride, triphenoxy emplified by Example 4. phosphorusdichloride and triphenylphosphorusdichloride 40 and thereafter recovering the resulting product. Example 4 7. The process of claim 6 wherein the diaminocyclo phosphazene is 4,6-diaminoperchlorocyclophosphazene. To a reaction vessel containing 90 parts of mono 8. The process according to claim 7 wherein the phos chlorobenzene and equipped with a water-cooled con phorus chloride is phosphorus pentachloride. denser were charged 13.4 parts of the product of Exam 9. The process according to claim 6 wherein the 4,6- ple 1 (II), and 19.7 parts of triphenylphosphorusdi 45 diaminocyclophosphazene is reacted with an alkali metal chloride, (C6H5)3PCl2. The mixture was refluxed until phenate to form diaminoperphenylcyclophosphazene and the evolution of hydrogen chloride ceased. Thereafter, thereafter reacting the diaminoperphenylcyclophos the monochlorobenzene was removed by distillation at phazene with a phosphorus chloride selected from the 135 degrees centigrade and at a reduced pressure of about group consisting of phosphorus pentachloride, triphen 50 millimeters of mercury to yield 31 parts of a yellow oxyphosphorusdichloride and triphenylphosphorusdi viscous oil considered to have the structure of com chloride. pound V. 10. The process according to claim 9 wherein the Example 5 phosphorus chloride is phosphorus pentachloride. Ten grams of the oily monomer of Example 3 was 11. The process according to claim 9 wherein the phos polymerized to a rubber polymer by heating it in a 5 5 phorus chloride is triphenoxyphosphorus dichloride. sealed tube placed in a molten bath held at 300 de grees centigrade for 4 hours. The rubber was very elas References Cited tic and remained stable on exposure to a moist at UNITED STATES PATENTS mosphere, retaining appreciable elasticity after one 60 2,876,248 3/1959 Ratz et al. ------260-461.303 month of such exposure. Differential thermal analysis 3,083,222 3/1963 Binder et al. ---- 260-461.303 on the rubber showed no major change up to a tempera 2,948,689 8/1960 Burg et al. ------260-2 ture of about 415 degrees centigrade. 3,071,552 1/1963 Burg ------260-2 Example 6 FOREIGN PATENTS Five grams of the oily monomer of Example 4 was 894,152 4/1962 Great Britain. polymerized to a useful resinous polymer by heating about 10 parts of it in a sealed tube placed in a molten bathheld OTHER REFERENCES at 400 degrees centigrade for 24 hours. Shaw et al., Chem. Reviews, vol. 62, 1962, pp. 247 277. Example 7 70 Ten grams of the oily monomer of Example 2 was CHARLES B. PARKER, Primary Examiner. polymerized to a rubber polymer by heating it in a sealed tube placed in a molten bath held at 300 degrees BERNARD HELFIN, Examiner. centigrade for 1 hour. The rubber resulting was found B. M. EISEN, A. H. SUTTO, Assistant Examiners.