Novel para-linked and CF3-substituted poly(amide-ether-imidazole)s: Solubility, optical and thermal properties

A new photoactive fluorinated diamine, 2-(4-trifluoromethylphenyl)-4,5-bis(4-(4-amino-2-trifluoromethylphenoxy)phenyl)imidazole (TFIA), was synthesized and used for preparation of novel fluorinated poly(amide-ether-imidazole)s (PAEIs) by using direct polycondensation of the diamine with various dicarboxylic acids. The resulting PAEIs were amorphous and had intrinsic viscosity [η] in the range of 0.68–0.80 dL/g. The weight average (Mw) and number average (Mn) molecular weights of one of the polymer, measured by GPC, were 18,600 g/mol and 11,500 g/mol, respectively. These polymers were readily soluble in a variety of organic solvents and formed low-colored and flexible thin films via solution casting. Their values of cut-off wavelength (λ0) were in the range of 380–390 nm, and all PAEIs films exhibited high optical transparency. According to thermal analysis, these polymers exhibited glass transition temperatures (Tg)s in the range of 160–250 °C, initial decomposition temperature (Ti) from 295 to 400 °C and temperature of 10% weight loss (T10%) from 400 to 490 °C in N2. These polymers exhibited strong UV–vis absorption at 310 nm in solution and in films and their fluorescence emission peaks appeared around 430–520 nm with the quantum yields in solution varied from 10% to 29%.