Triptycene based organosoluble polyamides: synthesis, characterization and study of the effect of chain flexibility on morphology

Abstract

Synthesis of new triptycene-containing polyamides (TPAs) using 2,6-diaminotriptycene and various aromatic and aliphatic dicarboxylates (Yamazaki–Higashi phosphorylation polyamidation) is described. The effect of the polymer backbone flexibility on the surface morphology of the respective polymer is studied. Polyamides thus prepared are organosoluble and have relatively low solution viscosities (0.18–0.5 dL g⁻¹). TGA indicated that triptycene polyamides containing aliphatic chains are thermally less stable than the wholly aromatic triptycene polyamides. These polyamides may be categorized as self-extinguishing materials. FTIR spectroscopy studies show that hydrogen bonding interactions are weaker in wholly aromatic polyamides (TPA1–TPA3) relative to those in semi-aromatic polyamides (TPA4–TPA6). FE-SEM images of TPAs show that replacement of aromatic dicarboxylates with aliphatic dicarboxylates results in a drastic change in the morphology of the polyamides.