Patent GB-1029042-A (GB)
Title: Triphosphonitrilic compounds,process for their production and polymers obtained therefrom
IPC: C08G79/02
Filed: 1964-03-18
Abstract: The invention comprises compounds of the general formula <FORM:1029042/C2/1> wherein R1 represents a phenyl radical, X represents halogen or an amino group and R represents a phenyl radical, halogen or an amino group.  Compounds in which X represents halogen and R represents a phenyl radical or a halogen atom are prepared by reacting 2,4,6-trihalo - 2,4,6 - triphenyl - triphosphonitrile with benzene in the presence of an aluminium halide such as aluminium trichloride or tribromide at a temperature of 50 DEG  to 90 DEG  C., said aluminium halide being present in an amount greater than 3 moles (preferably at least 6 moles, e.g. as high as 50 moles) per mole of 2,4,6-trihalo-2,4,6-triphenyltriphosphonitrile. The aluminium halide may be added to the reaction mixture all at once or in portions.  Dry inert gas such as nitrogen may be passed through the reaction mixture to remove hydrogen halide.  Complexes formed during the reaction may be decomposed by dilute mineral acids. Besides using benzene as a reactant for the process it may be used as a solvent and the preferred amount is from 10 to 100 parts by weight per part by weight of trihalotriphenyl-triphosphonitrile. Compounds in which X represents an amino radical and R represents an amino or phenyl radical are prepared by ammoniation of the corresponding halopolyphenyltriphosphonitrile which may be carried out either by contacting a solution of the halogen compound in an inert solvent with a gaseous ammonia, or by contacting the halogen compound with liquid ammonia.  Suitable solvents for the reaction include inert solvents such as CHCl3, CS2, CCl4 or C6H6.  Suitable temperatures for the reaction with gaseous ammonia are from about 0 DEG  to 80 DEG C., and when liquid ammonia is used from about - 75 DEG  to about - 35 DEG  C. are preferred.  Examples are given for the preparation of cis- and trans-2,4-dichloro-2,4,6,6 - tetraphenyltriphosphonitrile, 2 - chloro-2,4,4,6,6 - pentaphenyltriphosphonitrile and the corresponding diamino and amino compounds respectively.  The diamino compounds of the above formula polymerize on heating to a temperature from about 250 DEG  to 350 DEG  C. (see also Division C3) to form polymers having the recurring unit <FORM:1029042/C2/2> where R1 is a phenyl radical.  The polymers may have as terminal groups pentaphenyltriphosphonitrile groups, for example <FORM:1029042/C2/3> where n is an integer from 1 to 10 inclusive. Compounds of this structure may be obtained by condensing the diamino compound with a suitable amount of the monoamino compound.ALSO:The invention comprises a phosphonitrilic polymer having the recurring structural unit <FORM:1029042/C3/1> wherein R1 represents a phenyl radical.  It is prepared by heating a diamino compound of the formula <FORM:1029042/C3/2> (wherein R1 represents a phenyl radical) (see Division C2) to a temperature of from about 250 DEG  to 350 DEG  C. The diamino compound of the above formula may be used in its cis or trans forms or a mixture thereof.  The polymers can have as terminal groups pentaphenyltriphosphonitrile groups.  An example of such a polymer is <FORM:1029042/C3/3> wherein R1 represents a phenyl radical and n is an integer of from 1 to 10.  Polymers of this structure may be obtained by condensing the diamino compound with a suitable amount of a monoamino compound of the formula <FORM:1029042/C3/4> wherein R1 represents a phenyl radical, X represents an amino group and R represents a phenyl radical.  It is preferred to conduct the polymerization under reduced pressure or in an inert atmosphere.  The linear polymers can be cross-linked by using a small amount of a 2,4,6 - triamino - 2,4,6 - triphenyltriphosphonitrile. The preferred amount of the latter compound is from about 1% to about 25% by weight of the linear polymer.  An example of a cross-linked polymer is <FORM:1029042/C3/5> wherein R1 represents a phenyl radical.  Examples are given for the preparation of linear polymers from cis and/or trans 2,4-diamino-2,4,6,6 - tetraphenyltriphosphonitrile and for the preparation of a cross-linked polymer from the linear polymer (derived from the trans diamino compound) and trans-2,4,6-triamino-2,4,6 - triphenyltriphosphonitrile.  This polymer may be used in a coating composition (see Division B2).ALSO:Coating compositions comprising a polymer of the unit formula <FORM:1029042/B1-B2/1> wherein R1 represents a phenyl radical in a solvent such as chloroform, dimethylformamide or another suitable non-reactive solvent is applied to a substrate, the solvent evaporated and the polymer cured at a temperature of about 145 DEG to 350 DEG C.  In an example the coating composition is brushed on to anodized aluminium, stainless steel and titanium strips, dried and then heated at 145-150 DEG C., then at 200 DEG C., and finally at 300-325 DEG C. The invention also comprises a coating composition containing from about 1 to about 100 parts by weight of 2, 4-diamino-2, 4, 6, 6-tetraphenyltriphosphonitrile and one part by weight of 2, 4, 6-triamino-2, 4, 6-triphenyl triphosphonitrile dissolved in a volatile inert solvent, applied to an object to be coated and subsequently heating to a temperature of from about 145 DEG  to 350 DEG C.