A new kind of pyridine-containing aromatic diamine monomer, 4-phenyl-2,6-bis[4-(4-aminophenoxy)phenyl]-pyridine (PAPP), was successfully synthesized by a modified chichibabin reaction of benzaldehyde and a substituted acetophenone, 4-(4-nitrophenoxy)-acetophenone (NPAP), followed by a reduction of the resulting dinitro compound 4-phenyl-2,6-bis[4-(4-nitrophenoxy)phenyl]-pyridine (PNPP) with Pd/C and hydrazine monohydrate. The aromatic diamine was employed to synthesize a series of new pyridine-containing polyimides by polycondensation with various aromatic dianhydrides in Nmethy-2-pyrrolidone (NMP) via the conventional two-step method, i.e., ring-opening polycondensation forming the poly (amic acid)s and further thermal or chemical imidization forming polyimides. The inherent viscosities of the resulting polyimides were in the range of 0.79-1.13 dL/g, and most of them were soluble in common organic solvents such as N,N-dimethylacetamide (DMAc), NMP, and tetrahydrofuran (THF), etc. Meanwhile, strong and flexible polyimide films were obtained, which had good thermal stability, with the glass transition temperatures (T g ) of 268-3388C and the temperature at 5% weight loss of 521-5488C in air atmosphere, as well as outstanding mechanical properties with tensile strengths of 89.2-112.1 MPa and elongations at break of 9.5-15.4%. The polyimides also were found to possess low dielectric constants ranging from 2.53 to 3.11.

A new poly(arylene ether) (PAET) with terpyridine substituent groups has been synthesized which shows a turn-off fluorescent response in the presence of Ni(2+) over other cations and allows discrimination of these cations from each other on the basis of the extent of quenching.

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