Two new polytriazines: poly[2-methyl-4

6-(4

′ 4″-diphenylene)-1

3

5-triazine] (Ⅰ) and poly[2-phenyl-4

6-(4′

4″-diphenylene)-1

3

5-triazine] (Ⅱ) were synthesized from the solution condensation of biphenyl-4

4′-diamidine dihydrochloride with acetic anhydride and biphenyl-4

4′-diamidine with benzaldehyde respectively. These two polymers were characterized by TGA

DTA

elemental analysis and IR spectroscopy. They exhibited good thermal oxidative stability as shown by the fact that the powders of these polymers suffered 5.4%

2.4% weight loss after isothermal aging in air at 300℃ for 200 hours.The decomposition temperature of (Ⅱ) was 583℃ in air and 590℃ in N2.These linear poly-1

3

5-triazines were soluble in concentrated sulfuric acid

phosphoric acid and trifluoroacetic acid whereas the crosslinked poly-1

3

5-triazines reported in the literature were insoluble and infusible.It is interesting that these polymers can form complexes with metal halides as determined by X-ray photoelectron spectroscopy(XPS).The polymer metal complex(Ⅲ).PdCl2 possesses catalytic activity for hydrogenation.