Trifluoroacetaldehyde azine (TFAcAz) was-prepared as a new monomer and its polymerizabilities were studied. Poly(TFAcAz) was obtained by bulk polymerization with triethylamine at -20 degrees C, although only oligomers were obtained by typical anionic initiators. The structure and properties of the polymer were investigated by IR, Raman, and solid-state C-13 NMR spectroscopies, powder X-ray diffraction, and thermogravimetric analysis. The polymer is crystalline; composed of 1,2-addition units with pendant C=N double bonds, and decomposed to the monomer at about 200 degrees C.