Method for the preparation of bis(haloimides)

Abstract

Bis(halophthalimides) are prepared in a solvent such as ortho-dichlorobenzene or anisole, by a reaction at a temperature of at least 150° C. between at least one diamine compound and at least one halophthalic anhydride in the presence of imidization catalyst. The reaction produces a vapor stream comprising solvent and water formed as a by-product of the imidization reaction. A suitable vapor handling system comprising a partial reflux condenser is used to recycle the solvent, maintain the reactant concentration, conduct the reaction at a higher temperature, and effect more efficient conversion of reactants to product bis(halophthalimides). Reaction conditions disclosed may also be used to prepare organic polyimides.

1 . A method for preparing a bis(halophthalimide), said method comprising steps (a)-(d): 
 (a) contacting in a substantially water-immiscible solvent at least one halophthalic anhydride with at least one diamine to form a reaction mixture;    (b) heating the reaction mixture to form a product mixture comprising the substantially water-immiscible solvent and a product bis(halophthalimide), and a vapor stream comprising the substantially water immiscible solvent and water;    (c) introducing the vapor stream into a vapor handling system comprising a partial reflux condenser; and    (d) separating the vapor stream to provide a water-rich component and a solvent-rich component.    
     
     
         2 . The method of  claim 1  wherein said bis(halophthalimide) has structuture I  
       
         
           
           
               
               
           
         
       
       wherein X 1  is independently in each instance, a fluorine, chlorine, bromine or iodine group; R 1  is a hydrogen, C 1 -C 20  aliphatic radical, a C 2 -C 20  aromatic radical, or a C 4 -C 20  cycloaliphatic radical; Q is a C 2 -C 20  divalent aliphatic radical, a C 2 -C 40  divalent aromatic radical, or a C 4 -C 20  divalent cycloaliphatic radical; “a” is independently at each occurrence an integer in a range from 1 to 4; and “b” is independently at each occurrence an integer from 0 to 3.  
     
     
         3 . The method of  claim 1  wherein said halophthalic anhydride is 4-chlorophthalic anhydride, 3-chlorophthalic anhydride, 4-fluorophthalic anhydride, 3-fluorophthalic anhydride, 4,5-dichlorophthalic anhydride, 3,6-dichlorophthalic anhydride, or a mixture comprising at least two of the foregoing.  
     
     
         4 . The method of  claim 1  wherein the at least one diamine has structure II  
         H 2 N-Q-NH 2   II  
       wherein Q is a C 2 -C 20  divalent aliphatic radical, a C 2 -C 40  divalent aromatic radical, or a C 4 -C 20  divalent cycloaliphatic radical.  
     
     
         5 . The method of  claim 1  wherein the at least one diamine is selected from the group consisting of 4,4′-oxydianiline, and bis(4-aminophenyl)sulfone.  
     
     
         6 . The method of  claim 1  wherein said diamine is selected from the group consisting of aromatic diamines III and diamines IV  
       
         
           
           
               
               
           
         
       
       wherein R 2  and R 3  are independently at each occurrence a halogen atom, a nitro group, a cyano group, a C 1 -C 20  aliphatic radical, a C 2 -C 40  aromatic radical, or a C 4 -C 20  cycloaliphatic radical; and “n” and “m” are independently integers in a range from 0 to 4.  
     
     
         7 . The method of  claim 6  wherein the aromatic diamine is selected from the group consisting of meta-phenylene diamine and para-phenylene diamine.  
     
     
         8 . The method of  claim 1  wherein the solvent has a boiling point at atmospheric pressure of at least 110° C.  
     
     
         9 . The method of  claim 1  wherein the solvent is selected from the group consisting of chlorobenzene, ortho-dichlorobenzene, anisole, toluene, ortho-xylene, meta-xylene, para-xylene, mesitylene, phenetole, veratrole, and mixtures of the foregoing solvents.  
     
     
         10 . The method of  claim 1  wherein step (b) comprises heating the reaction mixture to at least about 150° C.  
     
     
         11 . The method of  claim 1  wherein the reaction mixture further comprises an imidization catalyst.  
     
     
         12 . The method of  claim 11  wherein the imidization catalyst comprises sodium phenylphosphinate.  
     
     
         13 . The method of  claim 1  wherein the halophthalic anhydride, and the diamine when taken together are present in an amount corresponding to an initial solids content of the reaction mixture in a range from about 5% to about 25% by weight.  
     
     
         14 . The method of  claim 1  wherein said contacting is carried out in a reaction vessel, and wherein the solvent-rich component is refluxed back into the reaction vessel.  
     
     
         15 . A method for preparing a bis(chlorophthalimide), said method comprising steps (a)-(d): 
 (a) contacting in a substantially water-immiscible solvent a mixture comprising at least one chlorophthalic anhydride and at least one diamine to form a reaction mixture;    (b) heating the reaction mixture to form a product mixture comprising said solvent and at least one product bis(chlorophthalimide), and a vapor stream comprising the substantially water-immiscible solvent and water;    (c) introducing the vapor stream into a vapor handling system comprising a partial reflux condenser; and    (d) separating the vapor stream to provide a water-rich component and a solvent-rich component.    
     
     
         16 . The method of  claim 15  wherein the solvent-rich component is refluxed back into the reactor.  
     
     
         17 . A method for preparing a bis(chlorophthalimide), said method comprising steps (a)-(d): 
 (a) contacting in a solvent comprising ortho-dichlorobenzene a mixture comprising at least one chlorophthalic anhydride, meta-phenylene diamine, and para-phenylene diamine to form a reaction mixture;    (b) heating the reaction mixture to form a product mixture comprising said solvent and product bis(chlorophthalimide) and a vapor stream comprising ortho-dichlorobenzene and water;    (c) introducing the vapor stream into a vapor handling system comprising a partial reflux condenser; and    (d) separating the vapor stream to provide a water-rich component and an ortho-dichlorobenzene-rich component.    
     
     
         18 . The method of  claim 17  wherein the solvent-rich component is refluxed back into the reactor.  
     
     
         19 . A method for preparing an organic polyimide, said method comprising steps (a)-(d): 
 (a) contacting in a substantially water-immiscible solvent a mixture comprising at least one dianhydride and at least one diamine to form a reaction mixture;    (b) heating the reaction mixture to form a product mixture comprising the substantially water-immiscible solvent and a product organic polyimide, and a vapor stream comprising the substantially water-immiscible solvent and water;    (c) introducing the vapor stream into a vapor handling system comprising a partial reflux condenser; and    (d) separating the vapor stream to provide a water-rich component and a solvent-rich component.    
     
     
         20 . The method of  claim 19  wherein the solvent comprises ortho-dichlorobenzene.  
     
     
         21 . The method of  claim 19  wherein the mixture further comprises an imidization catalyst.  
     
     
         22 . The method of  claim 21  wherein the imidization catalyst comprises sodium phenyl phosphinate.