A relatively high molecular weight polyphenyl-as-triazine (PPT) was preparedfrom two monomers--terephthalamidrazone and 1

4-bis (phenylglyoxaloyl) benzene.ηinh was equal to 1.93 dl/g (0.5% in eresol at 25℃) and T

was 320℃ as determined by differential thermal analysis (DTA).This polymer film exhibited good thermally oxidative stability and it's tensile strength at room temperature was higher than 1000 kg/em2. When the film was treated in boiling water for 200 hours

it retained good insulation (30-35 μ

1010Ω)and flexibility

and no change was observed in it's IR spectrum. The PPT film showed no loss in weight after being treated for 30 hours at 200℃ in water.