Synthesis and characterization of high-temperature fluorine-containing PMRpolyimides

The synthesis and characterization of novel fluorine-containing PMR polyimi des derived from the diethyl eater of 4,4'-(2,2,2-trifluoro-1-phenylethylid ene)diphthalic acid, p-phenylenediamine, and the monoethyl. eater of cis-5- norbornene-endo-2,3-dicarboxylic acid in low boiling solvents were describe d. The fluoropolyimide resin solutions are stable for several weeks at mom temperatures and can easily impregnate carbon fibers to prepare prepregs. T he molded resins exhibit outstanding thermal and thermooxidative stabilitie s at temperatures as high as 350 degrees C.