Fluorescent and electrochromic polyamides with pyrenylamine chromophore

A series of novel polyamides with a pyrenylamine chromophore in the backbone were prepared from a newly synthesized diamine monomer, N,N-di(4-aminophenyl)-1-aminopyrene,and various dicarboxylic acids via the phosphorylation polyamidation technique. These polyamides were readily soluble in many organic solvents and could be solution-cast into tough and amorphous films. They had useful levels of thermal stability with glass-transition temperatures in the range of 246-326 degrees C and 10% weight loss temperatures in excess of 500 degrees C. The dilute NMP solutions of these polyamides exhibited fluorescence maxima around 522-544 nm with quantum yields up to 30.2%. These polyamides also showed remarkable fluorescence solvatochromism in various solvents. The polymer films showed reversible electrochemical oxidation and reduction accompanied by strong color changes from the yellow neutral state to a purple oxidized state and to an orange reduced state. The anodically electrochromic films had high coloration efficiency (up to 172 cm(2) C-1 at 834 nm) and good redox stability, which still retained a high electroactivity after long-term redox cycles.