Polyimide resin composition
BACKGROUND OF THE INVENTION 
     The present invention relates to a molding resin composition, and more particularly relates to a molding resin composition of polyimide which is excellent in high-temperature stability, chemical resistance and mechanical strength as well as processing ability in molding. 
     Polyimide has so far been excellent in mechanical strength, dimensional stability, high-temperature stability, flame retardance and electrical insulative properties. Therefore polyimide has been used in the field of electric and electronic parts, aeronautics and space instruments and transport machinery. It is also expected for a wide use in the future in the field where high-temperature resistance is required. 
     A variety of polyimides which exhibit outstanding properties have been developed. Some polyimides, however, have no distinct glass transition temperature, although they are excellent in high-temperature stability. As a result, when employed as molding materials, specific methods such as sinter molding must be used for processing. Other polyimides which are excellent in processability have low glass transition temperatures and are soluble in halogenated hydrocarbons, which renders these polyimides unsatisfactory for use in applications which require high-temperature stability and solvent resistance. Thus, these polyimides have numerous advantages and disadvantages. 
     Accordingly a polyimide has been desired which is excellent in high-temperature stability and solvent resistance and also has an outstanding processing ability as a molding material. 
     The present inventors have found a polyimide which satisfies the aforementioned proparties. The polyimide has recurring units of the formula: ##STR2## wherein X is a divalent radical selected from the group consisting of a radical having the formula: ##STR3## and R is a tetravalent radical selected from the group consisting of an aliphatic radical having 2 or more carbon atoms, alicyclic radical, monoaromatic radical, fused polyaromatic radical, and polyaromatic radical where aromatic radicals are linked to one another directly or via a bridge member. 
     This polyimide is disclosed by Mitsui Toatsu Chemicals, Inc. in Japanese Laid-Open Patent Nos. TOKKAISHO 63-243132 (1988), 64-9226 (1989) and 64-9227 (1989). 
     The above polyimide is a thermoplastic polyimide having fluidity at high temperatures in addition to excellent mechanical, thermal and electrical properties. 
     Compared to ordinary engineering polymers represented by polyethylene terephthalate, polybutylene terephthalate, polysulfone and polyphenylene sulfide, polyimide is superior in high-temperature resistance and other properties. On the other hand, the processing ability of the polyimide is still inferior to these polymers. 
     Generally, in injection molding or extrusion molding, a lower melt viscosity leads to better processing ability. For example, a higher melt viscosity requires a higher injection pressure in the molding stage and the molded products are subject to excessive stress, thereby lowering operation efficiency and causing adverse effects on the properties of the molded products. The above stated polyimide can be injection molded because it has an excellent fluidity at high temperatures. Nevertheless it is desirable to enhance the workability of the polyimide. 
     SUMMARY OF THE INVENTION 
     The object of this invention is to provide a molding resin composition of polyimide which has a very excellent melt flowability without adverse affects on the essential properties of polyimide. 
     DETAILED DESCRIPTION OF THE INVENTION 
     The present invention relates to a polyimide resin composition comprised of 99.9 to 50.0% by weight of polyimide which consists essentially of recurring units of the formula: ##STR4## wherein X is a divalent radical selected from the group consisting of a radical having the formula: ##STR5## and R is a tetravalent radical selected from the group consisting of an aliphatic radical having 2 or more carbon atoms, alicyclic radical, monoaromatic radical, fused polyaromatic radical, and polyaromatic radical where aromatic radicals are linked to one another directly or via a bridge member, and 0.1 to 50.0% by weight of high-temperature engineering polymer selected from the group consisting of polyphenylene sulfide, aromatic polysulfone and aromatic polyetherimide. 
     Polyimide used in the method of this invention is derived from diamine of the following formula: ##STR6## where X is the same as above. 
     The diamine is bis[4-(3-(4-aminophenoxy)benzoyl)phenyl]ether or bis[4-(4-(4-aminophenoxy)phenoxy)phenyl]sulfone. 
     These diamines have the following formulae respectively: ##STR7## 
     The diamine is reacted with at least one of tetracarboxylic dianhydride in an organic solvent to yield polyamic acid. The polyamic acid is imidized to obtain polyimide. 
     The tetracarboxylic dianhydride used in the above reaction is an anhydride of the formula: ##STR8## where R is the same as above. 
     The tetracarboxylic dianhydride used in the method includes, for example, ethylenetetracarboxylic dianhydride, butanetetracarboxylic dianhydride, cyclopentanetetracarboxylic dianhydride, pyromellitic dianhydride, 
     3,3&#39;,4,4&#39;-benzophenonetetracarboxylic dianhydride, 
     2,2&#39;,3,3&#39;-benzophenonetetracarboxylic dianhydride, 
     3,3&#39;,4,4&#39;-biphenyltetracarboxylic dianhydride, 
     2,2&#39;3,3&#39;-biphenyltetracarboxylic dianhydride, 
     2,2-bis(3,4-dicarboxyphenyl)propane dianhydride, 
     2,2-bis(2,3-dicarboxyphenyl)propane dianhydride, 
     bis(3,4-dicarboxyphenyl) ether dianhydride, bis(2,3-dicarboxyphenyl) ether dianhydride, bis(3,4-dicarboxyphenyl) sulfone dianhydride, 
     1,1-bis-(2,3-dicarboxyphenyl)ethane dianhydride, 
     bis(2,3-dicarboxyphenyl)methane dianhydride, 
     bis(3,4-dicarboxyphenyl)methane dianhydride, 
     4,4&#39;-(p-phenylenedioxy)diphthalic dianhydride, 
     4,4&#39;-(m-phenylenedioxy)diphthalic dianhydride, 
     2,3,6,7-naphthalenetetracarboxylic dianhydride, 
     1,4,5,8-naphthalenetetracarboxylic dianhydride, 
     1,2,5,6-naphthalenetetracarboxylic dianhydride, 
     1,2,3,4-benzenetetracarboxylic dianhydride, 
     3,4,9,10-perylenetetracarboxylic dianhydride, 
     2,3,6,7-anthracenetetracarboxylic dianhydride and 
     1,2,7,8-phenanthrenetetracarboxylic dianhydride. 
     Particularly preferred tetracarboxylic dianhydrides are pyromellitic dianhydride, 3,3&#39;,4,4&#39;-biphenyltetracarboxylic dianhydride, 3,3&#39;,4,4&#39;-benzophenonetetracarboxylic dianhydride, bis(3,4-dicarboxyphenyl) ether dianhydride and 4,4&#39;-(p-phenylenedioxy)diphthalic dianhydride. 
     The tetracarboxylic dianhydride can be used singly or in mixtures of two or more. 
     The polyimide which is used in the composition of this invention is prepared by using the above stated diamine as a raw material. In order to obtain the composition of this invention, other diamines can also be used in combination with the diamine within the range which has no adverse effect on the advantageous properties of the polyimide. 
     Examples of diamines which may be used in admixture with the diamine include, m-phenylenediamine, o-phenylenediamine, p-phenylenediamine, m-aminobenzylamine, p-aminobenzylamine, bis(3-aminophenyl) ether, (3-aminophenyl) (4-aminophenyl) ether, bis(4-aminophenyl) ether, bis(3-aminophenyl) sulfide, (3-aminophenyl) (4-aminophenyl) sulfide, bis(4-aminophenyl) sulfide, bis(3-aminophenyl) sulfoxide, (3-aminophenyl) (4-aminophenyl) sulfoxide, bis(4-aminophenyl) sulfoxide, bis(3-aminophenyl) sulfone, (3-aminophenyl) (4-aminophenyl) sulfone, bis(4-aminophenyl) sulfone, 3,3&#39;-diaminobenzophenone, 3,4&#39;-diaminobenzophenone, 4,4&#39;-diaminobenzophenone, bis[4-(3-aminophenoxy)phenyl]methane, 
     bis[4-(4-aminophenoxy)phenyl]methane, 
     1,1-bis[4-(3-aminophenoxy)phenyl]ethane, 
     1,1-bis[4-(4-aminophenoxy)phenyl]ethane, 
     1,2-bis[4-(3-aminophenoxy)phenyl]ethane, 
     1,2-bis[4-(4-aminophenoxy)phenyl]ethane, 
     2,2-bis[4-(3-aminophenoxy)phenyl]propane, 
     2,2-bis[4-(4-aminophenoxy)phenyl]propane, 
     2,2-bis[4-(3-aminophenoxy)phenyl]butane, 
     2,2-bis[4-(4-aminophenoxy)phenyl]butane, 
     2,2-bis[4-(3-aminophenoxy)phenyl-1,1,1,3,3,3-hexafluoropropane, 
     2,2-bis[4-(4-aminophenoxy)phenyl-1,1,1,3,3,3-hexafluoropropane, 
     1,3-bis(3-aminophenoxy)benzene, 1,3-bis(4-aminophenoxy)benzene, 
     1,4-bis(3-aminophenoxy)benzene, 1,4-bis(4-aminophenoxy)benzene, 
     4,4&#39;-bis(3-aminophenoxy)biphenyl, 4,4&#39;-bis(4-aminophenoxy)biphenyl, 
     bis[4-(3-aminophenoxy)phenyl] ketone, 
     bis[4-(4-aminophenoxy)phenyl] ketone, 
     bis[4-(3-aminophenoxy)phenyl] sulfide, 
     bis[4-(4-aminophenoxy)phenyl] sulfide, 
     bis[4-(3-aminophenoxy)phenyl] sulfoxide, 
     bis[4-(4-aminophenoxy)phenyl] sulfoxide, 
     bis[4-(3-aminophenoxy)phenyl] sulfone, 
     bis[4-(4-aminophenoxy)phenyl] sulfone, 
     bis[4-(3-aminophenoxy)phenyl] ether and 
     bis[4-(4-aminophenoxy)phenyl] ether. 
     The high temperature engineering polymer which is used in the present invention includes, for example, polyphenylene sulfide, aromatic polysulfone and aromatic polyetherimide. 
     Polyphenylene sulfide is a resin having recurring units of the formula: ##STR9## The preparation process of the resin is disclosed, for example, by Phillips Petroleum Co. in U.S. Pat. No. 3,354,129 and Japanese Patent Publication TOKKOSHO 45-3368 (1970). The resin can be commercially available, for example, as RYTON (Trade Mark of Phillips Petroleum Co. in U.S.A.). According to the patent disclosure, polyphenylene sulfide is produced by reacting p-chlorobenzene with sodium sulfide monohydrate at 160-250° C. under pressure in N-methylpyrrolidone solvent. Polyphenylene sulfide includes various grades such as non-crosslinked or partially crosslinked polymers and polymers having different polymerization degrees. These grades can be easily produced by conducting a post-treatment process and are also available in the market. Therefore grades having suitable melt viscosity for the desired polymer blend can be optionally prepared or purchased in the market. 
     Aromatic polysulfone is a well known high temperature engineering polymer having a polymer chain represented by the formula: ##STR10## and described, for example, by V. J. Leslie et al, in CHEMITECH, July 1975, 426-432. 
     Representative examples of recurring units constituting aromatic polysulfone of this invention include: ##STR11## 
     Typical aromatic polysulfones include, for example, polysulfone consisting of recurring units represented by the formula: ##STR12## (Commercially available from Imperial Chemical Industries in Britain under the trademark VICTREX PES) and polysulfone consisting of recurring units represented by the formula: ##STR13## (Commercially available from Union Carbide Corp. in U.S.A. under the trademark UDEL POLYSULFONE). 
     Different grades of aromatic polysulfone having various polymerization degrees can be easily produced. Therefore grades having a suitable melt viscosity for the desired polymer blend can be optionally selected. 
     Aromatic polyetherimide is a polymer having both ether and imide linkages as a required bonding unit and is substantially composed of recurring units of the following formula: ##STR14## wherein Z is a trivalent aromatic radical where two valences out of three are connected with two adjacent carbon atoms, and Ar and Y are respectively a divalent monoaromatic radical and a divalent polyaromatic radical connected with a bridge member. 
     This polyetherimide is also a well known high temperature engineering polymer and is described, for example, by Takekoshi et al. in Polymer Preprint 24,(2),312-313 (1983). 
     Suitable examples of recurring units constituting aromatic polyetherimide of this invention include: ##STR15## 
     Aromatic polyetherimide is commercially available from General Electric Co. in U.S.A. under the trademarks ULTEM-1000, ULTEM-4000 and ULTEM-6000 etc. 
     Aromatic polyetherimide particularly consisting of recurring units of the formula: ##STR16## is commercially available from General Electric Co. under the trademark ULTEM-1000. 
     Several grades of aromatic polyetherimide having various polymerization degrees can be easily produced. Therefore grades having suitable melt viscosity for the desired polymer blend can be optionally selected. 
     The molding composition of resin in this invention is prepared so as to comprise to above mentioned polyimide in the range of 99.9 to 50.0% by weight and the high-temperature engineering polymer in the range of 0.1 to 50.0% by weight and total sum of 100% by weight. 
     The resin of this invention based on polyimide/polyphenylene sulfide exhibits remarkably low melt viscosity in a high temperature region above 350° C. The advantageous effect on melt viscosity obtained by the polyphenylene sulfide can be found even in small amounts. The lower limit of the amount in the composition is 0.1% by weight. The preferred amount is not less than 0.5% by weight. 
     Polyphenylene sulfide is excellent in chemical resistance, water absorption and flame retardance among the high-temperature stable resins. It, however, is inferior particularly in elongation at break and impact resistance. Therefore, too much polyphenylene sulfide in the above composition is unfavorable because the essential mechanical strength of polyimide can not be maintained. The amount of polyphenylene sulfide in the composition has an upper limit and is preferably 50.0% by weight or less. 
     The resin of this invention based on polyimide/aromatic polysulfone exhibits remarkably low melt viscosity in a high temperature region such as above 380° C. The advantageous effect on melt viscosity obtained by the aromatic polysulfone can be found even in a small amount. The lower limit of amount in the composition is 0.1% by weight. The preferred amount is not less than 0.5% by weight. 
     Aromatic polysulfone is excellent in mechanical strength at high temperatures among the high-temperature stable resins. It, however, is inferior to polyimide in mechanical strength, izod impact strength in particular. Therefore, too much aromatic polysulfone in the above composition is unfavorable because the essential mechanical strength of polyimide cannot be maintained. The amount of aromatic polysulfone in the composition has an upper limit and is preferably 50.0% by weight or less. 
     The resin of this invention based on polyimide/aromatic polyetherimide exhibits remarkably low melt viscosity as compared with polyimide alone in a high temperature region, above 350° C. in particular. The effect can be found even in a small amount of aromatic polyetherimide. The lower limit in the composition is 0.1% by weight. The preferred amount is not less than 0.5% by weight. 
     Aromatic polyetherimide is excellent in mechanical strength at high temperatures among the high-temperature stable resins. It, however, is inferior to polyimide in mechanical strength, izod impact strength in particular. Therefore, too much aromatic polyetherimide is unfavorable because the essential mechanical strength of polyimide cannot be maintained. 
     Aromatic polyetherimide is easily soluble in halogenated hydrocarbons such as methylene chloride and chloroform as well as amide type solvents such as dimethyl acetamide and N-methyl-pyrrolidone. Therefore, too much aromatic polyetherimide in the composition is unfavorable because the essential solvent resistance of polyimide cannot be maintained. 
     For these reasons, the amount of aromatic polyetherimide has an upper limit in the composition and is preferably 50.0% by weight or less. 
     In the preparation of the composition in this invention, known methods can be employed and, for example, the below described methods are preferred. 
     (1) Polyimide powder and high-temperature engineering polymer powder are pre-mixed to prepare a uniform mixture of powder by using a blender such as a mortar, Henschel mixer, drum blender, tumbler blender, ball mill or ribbon blender. 
     (2) Polyimide powder is previously dissolved or suspended in an organic solvent. High-temperature engineering polymer is added to the resulting solution or suspension and dispersed or dissolved uniformly, followed by removing the solvent to give a powdered mixture. 
     (3) High-temperature engineering polymer is suspended in an organic solvent solution of polyamic acid which is the precursor of polyimide in this invention. The resultant suspension is imidized by heat treatment at 100-400° C. or by chemical imidization with a usual imidizing agent, followed by removing the solvent to give a powdered mixture. 
     The powdered resin composition of polyimide thus obtained can be used as is for various molding applications such as injection molding, compression molding, transfer molding and extrusion molding. A more preferred method is fusion blending of the resins prior to molding. 
     Fusion blending of polyimide and high-temperature engineering polymer in the forms of, respectively, powder and powder, pellet and pellet, or powder and pellet is a simple and effective method. 
     Fusion blending can be carried out by using fusion blending equipment for known rubbers and plastics, for example, hot rolls, Banbury mixer, Brabender and extruder. The fusion temperature is set above the fusion temperature of the formulated system and below the initiation temperature of its decomposition. The temperature for blending polyimide with polyphenylene sulfide is normally in the range of 300-420° C. and preferably in the range of 320-400° C. The blending of polyimide with aromatic polysulfone or aromatic polyetherimide is carried out normally in the range of 280-420° C. and preferably in the range of 300-400° C. 
     As to the method of molding the resin composition in this invention, injection and extrusion molding are suitable because these methods form an uniform blend of fused polymers and have a high productivity. Other processing methods such as transfer molding, compression molding and sinter molding may also be applied. 
     In addition, the resin composition of this invention may contain at least one solid lubricant such as molybdenum disulfide, graphite, boron nitride, lead monoxide and lead powder. The composition may also contain at least one reinforcing material such as glass fibers, carbon fibers, aromatic polyamide fibers, potassium titanate fibers and glass beads. 
     The resin composition of this invention may contain at least one commonly used additive within the range which has no adverse effect on the object of this invention. Such additives include, for example, antioxidants, heat stabilizers, ultraviolet absorbers, flame retardants, auxiliary flame retardants, antistatic agents, lubricants and coloring agents. 
    
    
     EXAMPLES 
     The present invention will hereinafter be illustrated further in detail by way of synthesis examples, examples and comparative examples. 
     SYNTHESIS EXAMPLE 1 
     A reaction vessel equipped with a stirrer, reflux condenser and nitrogen inlet tube was charged with 5.92 kg (10 moles) of bis[4-(3-(4-aminophenoxy)benzoyl)phenyl] ether and 18.8 kg of N,N-dimethylacetamide. To the mixture was added 2.14 kg (9.8 moles) of pyromellitic dianhydride by portions in a nitrogen atmosphere at room temperature and at a rate to avoid a large temperature rise of the solution and stirred for 24 hours at room temperature. 
     To the resultant polyamic acid solution, 5.37 kg of N,N-dimethylacetamide was added, and then 4.08 kg (40 moles) of triethylamic and 6.03 kg (60 moles) of acetic anhydride were added dropwise in a nitrogen atmosphere at room temperature and further stirred for 24 hours at room temperature. The reaction mixture was poured into 250 l of water well stirred. The separated product was filtered, washed with methanol and dried at 150° C. for 24 hours under reduced pressure to obtain 7.47 kg of pale yellow polyimide powder (about 98% yield). The inherent viscosity of polyimide powder was 0.86 dl/g. The inherent viscosity was measured at 35° C. after dissolving 0.5 g of the polyimide powder in 100 ml of a solvent (a mixture of p-chlorophenol and phenol in a ratio of 90:10 by weight) at elevated temperatures and cooling the resulting solution. 
     The polyimide powder has a glass transition temperature of 235° C. in accordance with the DSC method. 
     
         ______________________________________                                    
Elemental analysis                                                        
           C         H      N                                             
______________________________________                                    
Calculated (%)                                                            
             74.42       3.38   3.62                                      
Found (%)    74.35       3.30   3.58                                      
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     SYNTHESIS EXAMPLES 2-5 
     The same procedures as Synthesis example 1 were carried out. However, raw materials were changed. The diamines and tetracarboxylic dianhydrides were varied to obtain various polyimide powders. Table 1 illustrates conditions for the synthesis of the polyimide resins, inherent viscosities and glass transition temperatures (Tg) thereof. 
     SYNTHESIS EXAMPLE 6 
     A reaction vessel equipped with a stirrer, reflux condenser and nitrogen inlet tube was charged with 61.67 kg (100 moles) of bis[4-4-(4-aminophenoxy)phenoxy)phenyl] sulfone and 473.0 kg of N,N-dimethylacetamide. To the mixture was added 20.7 kg (95 moles) of pyromellitic dianhydride by portions in a nitrogen atmosphere at room temperature and at a rate to avoid a large temperature rise of the solution and stirred for 20 hours at room temperature. 
     The inherent viscosity of the polyamic acid thus obtained was 0.56 dl/g. The inherent viscosity was measured at 35° C. after dissolving 0.5 g of the polyamic acid in 100 ml of N,N-dimethylacetamide. 
     To the resultant polyamic acid solution, 275 kg of N,N-dimethylacetamide was added, and then 40.4 kg (400 moles) of triethylamine and 61.2 kg (600 moles) of acetic anhydride were added dropwise in a nitrogen atmosphere at room temperature and stirred for 24 hours at room temperature. The reaction mixture was poured into 2,500 l of water well stirred. The separated product was filtered, washed with methanol and dried at 180° C. for 5 hours under reduced pressure to obtain 77.2 kg of polyimide powder (about 98% yield). 
     The polyimide powder had a glass transition temperature of 285° C. and melting point of 420° C. in accordance with the DSC method. 
     
                                           TABLE 1                                 
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                                              Inherent                    
Synthesis               Tetracarboxylic       Viscosity                   
                                                   Tg                     
example                                                                   
     Diamine      kg (mole)                                               
                        dianhydride    kg (mole)                          
                                              (dl/g)                      
                                                   (°C.)           
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2    Bis[4-(3-(4-aminophenoxy)-                                           
                  5.92 kg                                                 
                        3,3&#39;,4,4&#39;-Benzophenonetetra-                      
                                       3.16 kg                            
                                              0.67 198                    
     benzoyl)phenyl] ether                                                
                  (10 moles)                                              
                        carboxylic dianhydride                            
                                       (9.85 moles)                       
3    Bis[4-(3-(4-aminophenoxy)-                                           
                  5.92 kg                                                 
                        3,3&#39;,4,4&#39;-Biphenyltetra-                          
                                       2.90 kg                            
                                              0.69 107                    
     benzoyl)phenyl] ether                                                
                  (10 moles)                                              
                        carboxylic dianhydride                            
                                       (9.85 moles)                       
4    Bis[4-(3-(4-aminophenoxy)-                                           
                  4.74 kg                                                 
                        Pyromellitic dianhydride                          
                                       2.14 kg                            
                                              0.62 245                    
     benzoyl)phenyl] ether                                                
                  (8 moles)            (9.8 moles)                        
     Bis(4-aminophenyl) ether                                             
                  0.40 kg                                                 
                  (2 moles)                                               
5    Bis[4-(3-(4-aminophenoxy)-                                           
                  2.96 kg                                                 
                        Bis(3,4-dicarboxyphenyl) ether                    
                                        3.038 kg                          
                                              0.61 225                    
     benzoyl)phenyl] ether                                                
                  (5 moles)                                               
                        dianhydride    (9.8 moles)                        
     4,4&#39;-Bis(3-aminophenoxy)-                                            
                  1.84 kg                                                 
     biphenyl     (5 moles)                                               
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         ______________________________________                                    
Elemental analysis                                                        
            C    H         N      S                                       
______________________________________                                    
Calculated (%)                                                            
              69.17  3.26      3.51 4.01                                  
Found (%)     69.12  3.24      3.50 3.98                                  
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     SYNTHESIS EXAMPLES 7-10 
     The same procedures as Synthesis example 6 were carried out, except various tetracarboxylic dianhydrides were used in place of pyromellitic dianhydride. The amounts of diamine and tetracarboxylic dianhydrides were varied to obtain various polyimide powders. Table 2 illustrates conditions for the synthesis of the polyimide resins, inherent viscosities of the polyamic acids and glass transition temperatures (Tg) of the polyimides. 
     EXAMPLE 1-3 
     The polyimide powder obtained in Synthesis example 1 was dry blended with polyphenylene sulfide powder RYTON P-4 (a trademarked product of Phillips Petroleum Co.) in various compositions as illustrated in Table 3. The mixture was kneaded by fusing at 320-340° C. in a double screw extruder and extruded to obtain uniform pellets. The pellets thus obtained was injection molded with an Arburg injection molding machine (Type: All-round A-220 from Arburg Co.) at an injection temperature of 320-400° C. and a mold temperature of 150° C. The physical and thermal properties of the molded product were measured and the results are illustrated in Table 3. In Table 3, tensile strength and elongation at break, flexural strength and flexural modulus, izod impact strength, and heat distortion temperature were respectively measured in accordance with ASTM D-638, D-790, D-256 and D-648. 
     Besides Table 3 also illustrates minimum injection pressure which indicates melt flowability. Lower minimum injection pressure results from lower melt flowability. 
     
                                           TABLE 2                                 
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                                            Inherent                      
Synthesis               Tetracarboxylic     Viscosity                     
                                                 Tg                       
example                                                                   
     Diamine      kg (mole)                                               
                        dianhydride   kg (mole)                           
                                            (dl/g)                        
                                                 (°C.)             
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7    Bis[4-(4-(4-aminophenoxy)-                                           
                  61.67 kg                                                
                        3,3&#39;,4,4&#39;-Benzophenonetetra-                      
                                      30.59 kg                            
                                            0.53 242                      
     phenoxy)phenyl] sulfone                                              
                  (100 moles)                                             
                        carboxylic dianhydride                            
                                      (95 moles)                          
8    Bis[4-(4-(4-aminophenoxy)-                                           
                  61.67 kg                                                
                        Bis(3,4-dicarboxyphenyl)                          
                                      29.45 kg                            
                                            0.54 235                      
     phenoxy)phenyl] sulfone                                              
                  (100 moles)                                             
                        ether dianhydride                                 
                                      (95 moles)                          
9    Bis[4-(4-(4-aminophenoxy)-                                           
                  61.67 kg                                                
                        3,3&#39;,4,4&#39;-Biphenyltetra-                          
                                      27.93 kg                            
                                            0.51 261                      
     phenoxy)phenyl] sulfone                                              
                  (100 moles)                                             
                        carboxylic dianhydride                            
                                      (95 moles)                          
10   Bis[4-(4-(4-aminophenoxy)-                                           
                  61.67 kg                                                
                        4,4&#39;-(p-phenylenedioxy)-                          
                                      38.19 kg                            
                                            0.53 219                      
     phenoxy)phenyl] sulfone                                              
                  (100 moles)                                             
                        diphthalic dianhydride                            
                                      (95 moles)                          
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     COMPARATIVE EXAMPLE 1 
     The same procedures as Example 1-3 were carried out except that a composition outside the scope of this invention was used. The physical and thermal properties of molded specimens were measured and the results are illustrated in Table 3. 
     EXAMPLES 4-12 AND COMPARATIVE EXAMPLES 2-5 
     The procedures of Examples 1-3 were repeated by using the polyimide powder obtained in Synthesis examples 2-5 and polyphenylene sulfide powder RYTON-P-4 to give uniformly blended pellets. The pellets were injection molded. Physical and thermal properties were measured on the molded speciments. The results on both within and outside the scope of this invention are illustrated in Table 4 as Examples 4-12 and Comparative examples 2-5, respectively. 
     EXAMPLES 13-15 
     The polyimide powder obtained in Synthesis example 1 was dry blended with aromatic polysulfone powder UDEL POLYSULFONE P-1700 (a trademarked product of Union Carbide Corp.) in various compositions as illustrated in Table 5. The mixture was kneaded by fusing at 360-390° C. in a double screws extruder and extruded to obtain uniform pellets. The pellets thus obtained was injection molded at an injection temperature of 360-390° C. and a mold temperature of 170° C. The physical and thermal properties of the molded product were measured and the results are illustrated in Table 5. 
     The glass transition temperature was measured in accordance with the TMA penetration method. 
     
                                           TABLE 3                                 
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Example          Poly-                           Izod   Heat              
or               phenylene                                                
                        Minimum                  impact distortion        
Compara-                                                                  
      Polyimide  sulfide                                                  
                        injection                                         
                             Tensile                                      
                                  Elonga-                                 
                                       Flexural                           
                                            Flexural                      
                                                 strength                 
                                                        temperature       
tive  Synthesis  RYTON P-4                                                
                        pressure                                          
                             strength                                     
                                  tion strength                           
                                            modulus                       
                                                 (notched)                
                                                        (°C.)      
example                                                                   
      example                                                             
           (wt. parts)                                                    
                 (wt. parts)                                              
                        (kg/cm.sup.2)                                     
                             (kg/cm.sup.2)                                
                                  (%)  (kg/cm.sup.2)                      
                                            (kg/cm.sup.2)                 
                                                 (kg cm/cm)               
                                                        (18.6             
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                                                        kg/cm.sup.2)      
Ex. 1 1    95     5     450  960  93   1,400                              
                                            30,000                        
                                                 8.3    192               
Ex. 2 1    75    25     250  920  72   1,310                              
                                            33,000                        
                                                 7.4    187               
Ex. 3 1    50    50     *    890  48   1,200                              
                                            37,000                        
                                                 6.0    180               
Comp. 1                                                                   
      1    100    0     500  1,005                                        
                                  100  1,450                              
                                            28,000                        
                                                 8.4    200               
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 *Lower than detection limit of 40 kg/cm.sup.2.                           
 
    
     
                                           TABLE 4                                 
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Example          Poly-                           Izod   Heat              
or               phenylene                                                
                        Minimum                  impact distortion        
Compara-                                                                  
      Polyimide  sulfide                                                  
                        injection                                         
                             Tensile                                      
                                  Elonga-                                 
                                       Flexural                           
                                            Flexural                      
                                                 strength                 
                                                        temperature       
tive  Synthesis  RYTON P-4                                                
                        pressure                                          
                             strength                                     
                                  tion strength                           
                                            modulus                       
                                                 (notched)                
                                                        (°C.)      
example                                                                   
      example                                                             
           (wt. parts)                                                    
                 (wt. parts)                                              
                        (kg/cm.sup.2)                                     
                             (kg/cm.sup.2)                                
                                  (%)  (kg/cm.sup.2)                      
                                            (kg/cm.sup.2)                 
                                                 (kg cm/cm)               
                                                        (18.6             
__________________________________________________________________________
                                                        kg/cm.sup.2)      
Ex. 4 2    95    5      480  900  77   1,250                              
                                            24,000                        
                                                 7.0    177               
Ex. 5 2    50    50     280  830  43   1,180                              
                                            38,000                        
                                                 5.5    167               
Comp. 2                                                                   
      2    100   0      530  920  82   1,280                              
                                            23,000                        
                                                 7.2    181               
Ex. 6 3    95    5      420  870  72   1,150                              
                                            22,000                        
                                                 6.8    176               
Ex. 7 3    50    50     240  800  41   1,090                              
                                            36,000                        
                                                 5.2    166               
Comp. 3                                                                   
      3    100   0      480  900  75   1,190                              
                                            20,000                        
                                                 6.7    180               
Ex. 8 4    90    10     480  930  82   1,320                              
                                            31,500                        
                                                 7.2    214               
Ex. 9 4    50    50     260  850  48   1,230                              
                                            39,000                        
                                                 5.6    180               
Comp. 4                                                                   
      4    100   0      550  980  90   1,400                              
                                            29,100                        
                                                 7.5    227               
Ex. 10                                                                    
      5    95    5      430  1,000                                        
                                  120  1,280                              
                                            30,500                        
                                                 8.3    205               
Ex. 11                                                                    
      5    85    15     380  890  115  1,170                              
                                            32,000                        
                                                 8.0    197               
Ex. 12                                                                    
      5    75    25     330  790  109  1,120                              
                                            33,500                        
                                                 6.0    192               
Comp. 5                                                                   
      5    100   0      480  1,040                                        
                                  123  1,300                              
                                            28,100                        
                                                 8.5    208               
__________________________________________________________________________
 
    
     COMPARATIVE EXAMPLE 6 
     The same procedures as Examples 13-15 were carried out except that a composition outside the scope of this invention was used. The physical and thermal properties of molded specimens were measured and the results are illustrated in Table 5. 
     EXAMPLES 16-23 AND COMPARATIVE EXAMPLES 7-10 
     The procedures of Examples 13-15 were repeated except that the polyimide powder obtained in Synthesis examples 2-5 and aromatic polysulfone UDEL POLYSULFONE P-1700 were used to give uniformly blended pellets. The pellets were injection molded. Physical and thermal properties were measured on the molded specimens. The results on examples both within and outside the scope of this invention are illustrated in Table 6 as Examples 16-23 and Comparative examples 7-10, respectively. 
     EXAMPLES 24-27 
     The polyimide powder obtained in Synthesis example 1 was dry blended with aromatic polyetherimide ULTEM 1000 (a trademarked product of General Electric Co.) in various compositions as illustrated in Table 7. The mixture was kneaded by fusing at 370-400° C. in a double screw extruder and extruded to obtain uniform pellets. The pellets thus obtained was injection molded at an injection temperature of 360-390° C. and a mold temperature of 150° C. The physical and thermal properties of the molded product were measured and the results are illustrated in Table 7. 
     
                                           TABLE 5                                 
__________________________________________________________________________
              Aromatic                    Flex-                           
Example       Polysulfone                 ural                            
                                              Izod   Heat                 
or Com-       UDEL     Minimum   Elon-    modu-                           
                                              impact distortion           
para-                                                                     
     Polyimide                                                            
              POLYSULFONE                                                 
                       injection                                          
                            Tensile                                       
                                 ga- Flexural                             
                                          lus strength                    
                                                     temperature          
tive Synthesis                                                            
          (wt.                                                            
              P-1700   pressure                                           
                            strength                                      
                                 tion                                     
                                     strength                             
                                          (kg/                            
                                              (notched)                   
                                                     (°C.)         
                                                            Tg            
example                                                                   
     example                                                              
          parts)                                                          
              (wt. parts)                                                 
                       (kg/cm.sup.2)                                      
                            (kg/cm.sup.2)                                 
                                 (%) (kg/cm.sup.2)                        
                                          cm.sup.2)                       
                                              (kg cm/cm)                  
                                                     (18.6                
                                                            (°C.)  
__________________________________________________________________________
Ex. 13                                                                    
     1    95   5       400  1,000                                         
                                 100 1,430                                
                                          28,000                          
                                              8.3    195    230           
Ex. 14                                                                    
     1    75  25       300  930   94 1,360                                
                                          27,900                          
                                              8.0    191    222           
Ex. 15                                                                    
     1    50  50       260  880   86 1,300                                
                                          27,700                          
                                              7.7    186    210           
Comp. 6                                                                   
     1    100  0       500  1,005                                         
                                 100 1,450                                
                                          28,000                          
                                              8.4    200    235           
__________________________________________________________________________
 
    
     
                                           TABLE 6                                 
__________________________________________________________________________
              Aromatic                    Flex-                           
Example       Polysulfone                 ural                            
                                              Izod   Heat                 
or Com-       UDEL     Minimum   Elon-    modu-                           
                                              impact distortion           
para-                                                                     
     Polyimide                                                            
              POLYSULFONE                                                 
                       injection                                          
                            Tensile                                       
                                 ga- Flexural                             
                                          lus strength                    
                                                     temperature          
tive Synthesis                                                            
          (wt.                                                            
              P-1700   pressure                                           
                            strength                                      
                                 tion                                     
                                     strength                             
                                          (kg/                            
                                              (notched)                   
                                                     (°C.)         
                                                            Tg            
example                                                                   
     example                                                              
          parts)                                                          
              (wt. parts)                                                 
                       (kg/cm.sup.2)                                      
                            (kg/cm.sup.2)                                 
                                 (%) (kg/cm.sup.2)                        
                                          cm.sup.2)                       
                                              (kg cm/cm)                  
                                                     (18.6                
                                                            (°C.)  
__________________________________________________________________________
Ex. 16                                                                    
     2    95  5        420  900  81  1,250                                
                                          23,700                          
                                              7.2    180    197           
Ex. 17                                                                    
     2    50  50       270  830  77  1,190                                
                                          25,700                          
                                              7.2    177    195           
Comp. 7                                                                   
     2    100 0        500  920  82  1,280                                
                                          23,000                          
                                              7.2    181    198           
Ex. 18                                                                    
     3    90  10       370  890  72  1,200                                
                                          20,500                          
                                              6.9    183    205           
Ex. 19                                                                    
     3    50  50       260  880  65  1,230                                
                                          23,700                          
                                              7.6    192    218           
Comp. 8                                                                   
     3    100 0        480  900  75  1,190                                
                                          20,000                          
                                              6.7    180    197           
Ex. 20                                                                    
     4    95  5        430  970  83  1,380                                
                                          29,000                          
                                              7.6    223    241           
Ex. 21                                                                    
     4    50  50       280  930  73  1,360                                
                                          28,100                          
                                              8.2    216    235           
Comp. 9                                                                   
     4    100 0        550  980  90  1,400                                
                                          29,100                          
                                              7.5    227    245           
Ex. 22                                                                    
     5    95  5        390  1,000                                         
                                 118 1,300                                
                                          28,100                          
                                              8.4    204    222           
Ex. 23                                                                    
     5    50  50       250  920  100 1,210                                
                                          27,800                          
                                              7.9    193    218           
Comp. 10                                                                  
     5    100 0        480  1,040                                         
                                 123 1,300                                
                                          28,100                          
                                              8.5    208    225           
__________________________________________________________________________
 
    
     COMPARATIVE EXAMPLE 11 
     The same procedures as Examples 24-27 were carried out except that a composition outside the scope of this invention was used. The physical and thermal properties of molded specimens were measured and the results are illustrated in Table 7. 
     EXAMPLES 28-35 AND COMPARATIVE EXAMPLES 12-15 
     The procedures of Examples 24-27 were repeated except that the polyimide powder obtained in Synthesis examples 2-5 and aromatic polyetherimide ULTEM 1000 were used to give uniformly blended pellets. The pellets were injection molded. Physical and thermal properties were measured on the molded specimens. The results on examples both within and outside the scope of this invention are illustrated in Table 8 as Examples 28-35 and Comparative examples 12-15, respectively. 
     EXAMPLES 36-38 
     The polyimide powder obtained in Synthesis example 6 was dry blended with polyphenylene sulfide powder RYTON P-4 in various compositions as illustrated in Table 9. The mixture was kneaded by fusing at 320-420° C. in a double screw extruder and extruded to obtain uniform pellets. The pellets thus obtained was injection molded at an injection temperature of 320-420° C. and a mold temperature of 150° C. The physical and thermal properties of the molded product were measured and the results are illustrated in Table 9. 
     
                                           TABLE 7                                 
__________________________________________________________________________
Example          Aromatic                        Izod   Heat              
or               polyether-                                               
                        Minimum                  impact distortion        
Compara-                                                                  
      Polyimide  imide  injection                                         
                             Tensile                                      
                                  Elonga-                                 
                                       Flexural                           
                                            Flexural                      
                                                 strength                 
                                                        temperature       
tive  Synthesis  ULTEM-1000                                               
                        pressure                                          
                             strength                                     
                                  tion strength                           
                                            modulus                       
                                                 (notched)                
                                                        (°C.)      
example                                                                   
      example                                                             
           (wt. parts)                                                    
                 (wt. parts)                                              
                        (kg/cm.sup.2)                                     
                             (kg/cm.sup.2)                                
                                  (%)  (kg/cm.sup.2)                      
                                            (kg/cm.sup.2)                 
                                                 (kg cm/cm)               
                                                        (18.6             
__________________________________________________________________________
                                                        kg/cm.sup.2)      
Ex. 24                                                                    
      1    95     5     500  1,010                                        
                                  95   1,450                              
                                            28,500                        
                                                 8.3    200               
Ex. 25                                                                    
      1    85    15     460  1,020                                        
                                  91   1,455                              
                                            29,600                        
                                                 8.0    200               
Ex. 26                                                                    
      1    75    25     430  1,030                                        
                                  86   1,460                              
                                            30,400                        
                                                 7.6    200               
Ex. 27                                                                    
      1    50    50     400  1,040                                        
                                  80   1,470                              
                                            31,000                        
                                                 7.0    200               
Comp. 11                                                                  
      1    100    0     500  1,005                                        
                                  100  1,450                              
                                            28,000                        
                                                 8.4    200               
__________________________________________________________________________
 
    
     
                                           TABLE 8                                 
__________________________________________________________________________
Example          Aromatic                        Izod   Heat              
or               polyether-                                               
                        Minimum                  impact distortion        
Compara-                                                                  
      Polyimide  imide  injection                                         
                             Tensile                                      
                                  Elonga-                                 
                                       Flexural                           
                                            Flexural                      
                                                 strength                 
                                                        temperature       
tive  Synthesis  ULTEM-1000                                               
                        pressure                                          
                             strength                                     
                                  tion strength                           
                                            modulus                       
                                                 (notched)                
                                                        (°C.)      
example                                                                   
      example                                                             
           (wt. parts)                                                    
                 (wt. parts)                                              
                        (kg/cm.sup.2)                                     
                             (kg/cm.sup.2)                                
                                  (%)  (kg/cm.sup.2)                      
                                            (kg/cm.sup.2)                 
                                                 (kg cm/cm)               
                                                        (18.6             
__________________________________________________________________________
                                                        kg/cm.sup.2)      
Ex. 28                                                                    
      2    90    10     470  960  80   1,300                              
                                            24,600                        
                                                 7.0    183               
Ex. 29                                                                    
      2    50    50     390  1,000                                        
                                  73   1,390                              
                                            28,450                        
                                                 6.4    190               
Comp. 12                                                                  
      2    100    0     530  920  82   1,280                              
                                            23,000                        
                                                 7.2    181               
Ex. 30                                                                    
      3    70    30     415  920  70   1,230                              
                                            23,100                        
                                                 6.4    183               
Ex. 31                                                                    
      3    50    50     400  980  68   1,350                              
                                            27,000                        
                                                 6.0    190               
Comp. 13                                                                  
      3    100    0     480  900  75   1,190                              
                                            20,000                        
                                                 6.7    180               
Ex. 32                                                                    
      4    95     5     480  1,000                                        
                                  85   1,420                              
                                            30,000                        
                                                 7.4    223               
Ex. 33                                                                    
      4    75    25     400  1,020                                        
                                  70   1,460                              
                                            32,400                        
                                                 7.0    219               
Comp. 14                                                                  
      4    100    0     550  980  90   1,400                              
                                            29,100                        
                                                 7.5    227               
Ex. 34                                                                    
      5    75    25     420  1,050                                        
                                  112  1,350                              
                                            32,300                        
                                                 7.9    206               
Ex. 35                                                                    
      5    50    50     380  1,060                                        
                                  94   1,400                              
                                            31,000                        
                                                 7.1    204               
Comp. 15                                                                  
      5    100    0     480  1,040                                        
                                  123  1,300                              
                                            28,100                        
                                                 8.5    208               
__________________________________________________________________________
 
    
     COMPARATIVE EXAMPLE 16-17 
     The same procedures as Examples 36-38 were carried out except that a composition outside the scope of this invention was used. The physical and thermal properties of molded specimens were measured and the results are illustrated in Table 9. 
     EXAMPLES 39-47 AND COMPARATIVE EXAMPLES 18-21 
     The procedures of Examples 36-38 were repeated except that the polyimide powder obtained in Synthesis exaples 7-10 and polyphenylene sulfide powder RYTON P-4 were used to give uniformly blended pellets. The pellets were injection molded. Physical and thermal properties were measured on the molded specimens. The results on examples both within and outside the scope of this invention are illustrated in Table 10 as Examples 39-47 and Comparative examples 18-21, respectively. 
     EXAMPLES 48-50 
     The polyimide powder obtained in Synthesis example 6 was dry blended with aromatic polysulfone UDEL POLYSULFONE P-1700 in various compositions as illustrated in Table 11. The mixture was kneaded by fusing in a double screw extruder and extruded to obtain uniform pellets. The pellets thus obtained were injection molded at an injection temperature of 380-400° C. and a mold temperature of 170° C. The physical and thermal properties of the molded product were measured and the results are illustrated in Table 11. 
     COMPARATIVE EXAMPLE 22 
     The same procedures as Examples 48-50 were carried out except that a composition outside the scope of this invention was used. The physical and thermal properties of molded specimens were measured and the results are illustrated in Table 11. 
     
                                           TABLE 9                                 
__________________________________________________________________________
Example          Poly-                           Izod   Heat              
or               phenylene                                                
                        Minimum                  impact distortion        
Compara-                                                                  
      Polyimide  sulfide                                                  
                        injection                                         
                             Tensile                                      
                                  Elonga-                                 
                                       Flexural                           
                                            Flexural                      
                                                 strength                 
                                                        temperature       
tive  Synthesis  RYTON P-4                                                
                        pressure                                          
                             strength                                     
                                  tion strength                           
                                            modulus                       
                                                 (notched)                
                                                        (°C.)      
example                                                                   
      example                                                             
           (wt. parts)                                                    
                 (wt. parts)                                              
                        (kg/cm.sup.2)                                     
                             (kg/cm.sup.2)                                
                                  (%)  (kg/cm.sup.2)                      
                                            (kg/cm.sup.2)                 
                                                 (kg cm/cm)               
                                                        (18.6             
__________________________________________________________________________
                                                        kg/cm.sup.2)      
Ex. 36                                                                    
      6    95     5     360  980  38   1,480                              
                                            34,000                        
                                                 18.2   254               
Ex. 37                                                                    
      6    80    20     240  930  34   1,400                              
                                            36,000                        
                                                 15.9   239               
Ex. 38                                                                    
      6    50    50     130  850  20   1,250                              
                                            38,000                        
                                                 12.0   205               
Comp. 16                                                                  
      6    100    0     500  1,000                                        
                                  40   1,500                              
                                            29,000                        
                                                 18.9   260               
Comp. 17                                                                  
      6     0    100    *    680    1.6                                   
                                       1,000                              
                                            42,000                        
                                                  2.4   140               
__________________________________________________________________________
 *Lower than detection limit of 40 kg/cm.sup.2.                           
 
    
     
                                           TABLE 10                                
__________________________________________________________________________
Example          Poly-                           Izod   Heat              
or               phenylene                                                
                        Minimum                  impact distortion        
Compara-                                                                  
      Polyimide  sulfide                                                  
                        injection                                         
                             Tensile                                      
                                  Elonga-                                 
                                       Flexural                           
                                            Flexural                      
                                                 strength                 
                                                        temperature       
tive  Synthesis  RYTON P-4                                                
                        pressure                                          
                             strength                                     
                                  tion strength                           
                                            modulus                       
                                                 (notched)                
                                                        (°C.)      
example                                                                   
      example                                                             
           (wt. parts)                                                    
                 (wt. parts)                                              
                        (kg/cm.sup.2)                                     
                             (kg/cm.sup.2)                                
                                  (%)  (kg/cm.sup.2)                      
                                            (kg/cm.sup.2)                 
                                                 (kg cm/cm)               
                                                        (18.6             
__________________________________________________________________________
                                                        kg/cm.sup.2)      
Ex. 39                                                                    
      7    95    5      360  900  17   1,320                              
                                            25,300                        
                                                 10.0   213               
Ex. 40                                                                    
      7    50    50     240  800  11   1,150                              
                                            32,600                        
                                                  8.0   180               
Comp. 18                                                                  
      7    100   0      500  910  18   1,340                              
                                            20,000                        
                                                 10.3   217               
Ex. 41                                                                    
      8    95    5      350  990  27   1,430                              
                                            32,000                        
                                                 12.5   207               
Ex. 42                                                                    
      8    50    50     200  850  16   1,260                              
                                            37,300                        
                                                  9.0   175               
Comp. 19                                                                  
      8    100   0      480  1,000                                        
                                  28   1,450                              
                                            28,000                        
                                                 13.0   210               
Ex. 43                                                                    
      9    90    10     340  1,010                                        
                                  30   1,260                              
                                            30,800                        
                                                 14.2   227               
Ex. 44                                                                    
      9    50    50     220  890  17   1,200                              
                                            35,500                        
                                                  9.0   188               
Comp. 20                                                                  
      9    100   0      550  1,040                                        
                                  32   1,380                              
                                            25,600                        
                                                 15.5   236               
Ex. 45                                                                    
      10   95    5      340  980  35   1,460                              
                                            32,800                        
                                                 14.3   193               
Ex. 46                                                                    
      10   85    15     320  960  32   1,410                              
                                            34,000                        
                                                 13.1   188               
Ex. 47                                                                    
      10   75    25     240  930  28   1,360                              
                                            36,000                        
                                                 11.8   182               
Comp. 21                                                                  
      10   100   0      460  1,000                                        
                                  37   1,480                              
                                            28,500                        
                                                 15.0   196               
__________________________________________________________________________
 
    
     
                                           TABLE 11                                
__________________________________________________________________________
              Aromatic                    Flex-                           
Example       Polysulfone                 ural                            
                                              Izod   Heat                 
or Com-       UDEL     Minimum   Elon-    modu-                           
                                              impact distortion           
para-                                                                     
     Polyimide                                                            
              POLYSULFONE                                                 
                       injection                                          
                            Tensile                                       
                                 ga- Flexural                             
                                          lus strength                    
                                                     temperature          
tive Synthesis                                                            
          (wt.                                                            
              P-1700   pressure                                           
                            strength                                      
                                 tion                                     
                                     strength                             
                                          (kg/                            
                                              (notched)                   
                                                     (°C.)         
                                                            Tg            
example                                                                   
     example                                                              
          parts)                                                          
              (wt. parts)                                                 
                       (kg/cm.sup.2)                                      
                            (kg/cm.sup.2)                                 
                                 (%) (kg/cm.sup.2)                        
                                          cm.sup.2)                       
                                              (kg cm/cm)                  
                                                     (18.6                
                                                            (°C.)  
__________________________________________________________________________
Ex. 48                                                                    
     6    95   5       470  990  42  1,480                                
                                          28,900                          
                                              18.3   256    280           
Ex. 49                                                                    
     6    75  25       380  930  48  1,400                                
                                          28,600                          
                                              15.9   239    261           
Ex. 50                                                                    
     6    50  50       310  860  55  1,300                                
                                          28,300                          
                                              13.5   218    238           
Comp. 22                                                                  
     6    100  0       500  1,000                                         
                                 40  1,500                                
                                          29,000                          
                                              18.9   260    285           
__________________________________________________________________________
 
    
     EXAMPLES 51-58 AND COMPARATIVE EXAMPLES 23-26 
     The procedures of Examples 48-50 were repeated except that the polyimide powder obtained in Synthesis examples 7-10 and aromatic polysulfone VICTREX PES 3600P (a trademarked product of Imperial Chemical Industries) or aromatic polysulfone UDEL POLYSULFONE P-1700 were used to give uniformly blended pellets. The pellets were injection molded. Physical and thermal properties were measured on the molded specimens. The results on examples both within and outside the scope of this invention are illustrated in Table 12 as Examples 51-58 and Comparative examples 23-26, respectively. 
     EXAMPLES 59-62 
     The polyimide powder obtained in Synthesis example 6 was dry blended with aromatic polyetherimide ULTEM 1000 in various compositions as illustrated in Table 13. The mixture was kneaded by fusing at 350-370° C. in a double screw extruder and extruded to obtain uniform pellets. The pellets thus obtained were injection molded at an injection temperature of 380-400° C. and a mold temperature of 170° C. The physical and thermal properties of the molded product were measured and the results are illustrated in Table 13. 
     COMPARATIVE EXAMPLE 27 
     The same procedures as Examples 59-62 were carried out except that a composition outside the scope of this invention was used. The physical and thermal properties of molded specimens were measured and the results are illustrated in Table 13. 
     
                                           TABLE 12                                
__________________________________________________________________________
                                         Flex-                            
Example                                                                   
     Polyimide                           ural                             
                                             Izod   Heat                  
or Com-                                                                   
     Syn-    Aromatic Minimum   Elon-    modu-                            
                                             impact distortion            
para-                                                                     
     thesis  Poly-    injection                                           
                           Tensile                                        
                                ga- Flexural                              
                                         lus strength                     
                                                    temperature           
tive ex- (wt.                                                             
             sulfone                                                      
                  (wt.                                                    
                      pressure                                            
                           strength                                       
                                tion                                      
                                    strength                              
                                         (kg/                             
                                             (notched)                    
                                                    (°C.)          
                                                           Tg             
example                                                                   
     ample                                                                
         parts)                                                           
             U* or V*                                                     
                  parts)                                                  
                      (kg/cm.sup.2)                                       
                           (kg/cm.sup.2)                                  
                                (%) (kg/cm.sup.2)                         
                                         cm.sup.2)                        
                                             (kg cm/cm)                   
                                                    (18.6                 
                                                           (°C.)   
__________________________________________________________________________
Ex. 51                                                                    
     7   95  U    5   480  900  21  1,330                                 
                                         20,400                           
                                             10.1   215    239            
Ex. 52                                                                    
     7   50  U    50  320  820  44  1,220                                 
                                         23,800                           
                                              8.7   196    216            
Comp. 23                                                                  
     7   100      0   530  910  18  1,340                                 
                                         20,000                           
                                             10.3   217    242            
Ex. 53                                                                    
     8   90  V    10  420  990  30  1,440                                 
                                         27,800                           
                                             12.6   209    234            
Ex. 54                                                                    
     8   50  V    50  300  930  39  1,390                                 
                                         27,300                           
                                             10.9   207    230            
Comp. 24                                                                  
     8   100      0   480  1,000                                          
                                29  1,450                                 
                                         28,000                           
                                             13.0   210    235            
Ex. 55                                                                    
     9   95  V    5   480  1,030                                          
                                33  1,380                                 
                                         25,600                           
                                             15.2   234    259            
Ex. 56                                                                    
     9   50  V    50  310  950  41  1,350                                 
                                         26,000                           
                                             12.1   220    243            
Comp. 25                                                                  
     9   100      0   550  1,040                                          
                                32  1,380                                 
                                         25,600                           
                                             15.5   236    261            
Ex. 57                                                                    
     10  95  U    5   430  990  39  1,460                                 
                                         28,400                           
                                             14.6   195    218            
Ex. 58                                                                    
     10  50  U    50  300  860  54  1,290                                 
                                         28,000                           
                                             11.0   186    205            
Comp. 26                                                                  
     10  100      0   460  1,040                                          
                                37  1,480                                 
                                         28,500                           
                                             15.5   196    219            
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 *U: UDEL POLYSULFONE P1700                                               
 V: VICTREX PES 3600P                                                     
 
    
     
                                           TABLE 13                                
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Example          Aromatic                        Izod   Heat              
or               polyether-                                               
                        Minimum                  impact distortion        
Compara-                                                                  
      Polyimide  imide  injection                                         
                             Tensile                                      
                                  Elonga-                                 
                                       Flexural                           
                                            Flexural                      
                                                 strength                 
                                                        temperature       
tive  Synthesis  ULTEM-1000                                               
                        pressure                                          
                             strength                                     
                                  tion strength                           
                                            modulus                       
                                                 (notched)                
                                                        (°C.)      
example                                                                   
      example                                                             
           (wt. parts)                                                    
                 (wt. parts)                                              
                        (kg/cm.sup.2)                                     
                             (kg/cm.sup.2)                                
                                  (%)  (kg/cm.sup.2)                      
                                            (kg/cm.sup.2)                 
                                                 (kg cm/cm)               
                                                        (18.6             
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                                                        kg/cm.sup.2)      
Ex. 59                                                                    
      6    95     5     470  1,000                                        
                                  41   1,500                              
                                            29,300                        
                                                 18.2   257               
Ex. 60                                                                    
      6    85    15     440  1,000                                        
                                  43   1,500                              
                                            29,700                        
                                                 16.7   251               
Ex. 61                                                                    
      6    75    25     420  1,000                                        
                                  45   1,500                              
                                            30,200                        
                                                 15.2   245               
Ex. 62                                                                    
      6    50    50     390  1,000                                        
                                  50   1,510                              
                                            31,400                        
                                                 11.5   230               
Comp. 27                                                                  
      6    100    0     500  1,000                                        
                                  40   1,500                              
                                            29,000                        
                                                 18.9   260               
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     EXAMPLES 63-70 AND COMPARATIVE EXAMPLES 28-31 
     The procedures of Examples 59-62 were repeated the polyimide powder obtained in Synthesis examples 7-10 and aromatic polyetherimide ULTEM 1000 were used to give uniformly blended pellets. The pellets were injection molded. Physical and thermal properties were measured on the molded specimens. The results on examples both within and outside the scope of this invention are illustrated in Table 14 as Examples 63-70 and Comparative examples 28-31, respectively. 
     
                                           TABLE 14                                
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Example          Aromatic                        Izod   Heat              
or               polyether-                                               
                        Minimum                  impact distortion        
Compara-                                                                  
      Polyimide  imide  injection                                         
                             Tensile                                      
                                  Elonga-                                 
                                       Flexural                           
                                            Flexural                      
                                                 strength                 
                                                        temperature       
tive  Synthesis  ULTEM-1000                                               
                        pressure                                          
                             strength                                     
                                  tion strength                           
                                            modulus                       
                                                 (notched)                
                                                        (°C.)      
example                                                                   
      example                                                             
           (wt. parts)                                                    
                 (wt. parts)                                              
                        (kg/cm.sup.2)                                     
                             (kg/cm.sup.2)                                
                                  (%)  (kg/cm.sup.2)                      
                                            (kg/cm.sup.2)                 
                                                 (kg cm/cm)               
                                                        (18.6             
__________________________________________________________________________
                                                        kg/cm.sup.2)      
Ex. 63                                                                    
      7    90    10     480    920                                        
                                  22   1,360                              
                                            21,400                        
                                                  9.5   215               
Ex. 64                                                                    
      7    50    50     400    960                                        
                                  39   1,430                              
                                            26,900                        
                                                  7.2   209               
Comp. 28                                                                  
      7    100    0     530    910                                        
                                  18   1,340                              
                                            20,000                        
                                                 10.3   217               
Ex. 65                                                                    
      8    70    30     400  1,000                                        
                                  38   1,470                              
                                            29,700                        
                                                 10.3   207               
Ex. 66                                                                    
      8    50    50     380  1,000                                        
                                  44   1,490                              
                                            30,900                        
                                                  8.5   205               
Comp. 29                                                                  
      8    100    0     480  1,000                                        
                                  28   1,450                              
                                            28,000                        
                                                 13.0   210               
Ex. 67                                                                    
      9    95     5     510  1,040                                        
                                  33   1,390                              
                                            26,000                        
                                                 14.9   234               
Ex. 68                                                                    
      9    75    25     450  1,030                                        
                                  39   1,420                              
                                            27,600                        
                                                 12.6   227               
Comp. 30                                                                  
      9    100    0     550  1,040                                        
                                  32   1,380                              
                                            25,600                        
                                                 15.5   236               
Ex. 69                                                                    
      10   75    25     410  1,000                                        
                                  43   1,490                              
                                            29,800                        
                                                 12.3   197               
Ex. 70                                                                    
      10   50    50     380  1,000                                        
                                  49   1,500                              
                                            31,100                        
                                                  9.5   198               
Comp. 31                                                                  
      10   100    0     460  1,000                                        
                                  37   1,480                              
                                            28,500                        
                                                 15.0   196               
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