An improved synthetic route to a previously prepared self-polymerizable poly(phenylquinoxaline) (PPQ) monomer mixture, i.e., 2-(4-hydroxyphenyl)-3-phenyl-6-fluoroquinoxaline and 3-(4-hydroxyphenyl)-2-phenyl-6-fluoroquinoxaline was developed. The monomer mixture was then polymerized in stages in N-methyl-2-pyrrolidinone/toluene and in N-cyclohexyl-2-pyrrolidinone at elevated temperatures in the presence of potassium carbonate. Polymer samples were obtained that had intrinsic viscosities as high as 1.64 dl/g in In-cresol at 30.0 +/- 0.1 degrees C and glass transition temperatures (T(g)s) of 250-252 degrees C. Thin films of the PPQ had a room temperature (RT) tensile strength of 114 MPa, a RT Young＇s modulus of 3.7 GPa, and a RT elongation at break; of 93%. The neat resin had a flexural modulus of 3.12 GPa, a fracture energy (G(1c)) of 2170 J/m(2) and a titanium-titanium lap shear strength of 31.4 MPa at room temperature. The polymer melt underwent shear thinning at 320 degrees C. The melt viscosity decreased from 10(5) to 10(6) Pa s to less than 10(4) Pa s as the frequency was increased from 10(-2) to 10(2) rad/s. Carbon-fiber(T650)(R)-reinforced composites of the PPQ were prepared and their mechanical properties determined.