Synthesis, characterization and nanoparticle formation of polyarylene poly(amic acid)s and polyimides containing fluorescent dye moieties

New naphthalene‐ and perylene‐containing polyarylene poly(amic acid)s and polyimides were synthesized from a new phenylated phenylenediamine. A small‐molecule model compound was also synthesized with naphthalene end‐groups. The new compounds were characterized, and the structures were confirmed using 1H NMR and attenuated total reflectance Fourier transform infrared spectroscopy. Thermal characterization was conducted using thermogravimetric analysis and differential scanning calorimetry. Onset of thermal degradation temperatures for the naphthalene and perylene polyimides were 561 and 545 °C, and char yields at 1000 °C were 61 and 59% (under nitrogen), respectively. The glass transition temperatures were 381 and 396 °C, respectively. Molecular weights determined using gel permeation chromatography were Mw = 35 000 and 24 000 g mol−1, respectively. The absorption maxima were at 387 and 427/458/491/527 nm, respectively, while the fluorescence emission maxima were at 498 and 541/582 nm, respectively. Nanoparticles were prepared from these new fluorescent dye‐containing polyarylene polyimides with sizes of 102/397 and 177 nm, respectively, as determined using dynamic light scattering. © 2020 Society of Industrial Chemistry A highly phenylated phenylenediamine was used for the synthesis of dye‐containing poly(amic acid)s and polyimides.