Synthesis of soluble and thermally stable triptycene-based poly(amide-imide)s

A series of new triptycene-based poly(amide-imide)s (PAIs) were prepared by the phosphorylation polyamidation reactions from 1,4-bis(4-trimellitimidophenoxy) triptycene with aromatic diamines. Most of the resulting PAIs were readily soluble in many organic solvents and could be solution-cast into tough and flexible polymer films. These PAIs exhibited glass-transition temperatures (Tgs) in the range of 274-305 degrees C, and they did not show significant weight-loss before 500 degrees C. In comparison with the structurally similar PAIs without the triptycene unit, the present PAIs exhibited higher solubility, lower crystallization tendency, and better film-forming ability.