Poly(2‐imidazolin‐5‐ones)—A new class of heterocyclic polymers

The reaction of bisazlactones (2‐oxazolin‐5‐ones) with primary diamines containing additional secondary or tertiary amine functionality (e.g., diethylenetriamine, triethylenetetramine, or N‐methyliminobispropylamine) readily produces polyamides which serve as precursors to a new class of heterocyclic polymers. Thermal cyclodehydration takes place under relatively mild conditions (180–200°C) to produce water‐soluble polymers containing the 2‐imidazolin‐5‐one heterocycle. Model reactions have been studied to verify this mode of cyclization and confirm the proposed polymer structure.