Ionic liquid-containing coordination polymer: solvent-free synthesis, incongruent melting, and glass formation

An ionic-liquid-containing 2D coordination polymer was synthesized via a solvent-free reaction. The material exhibited incongruent melting at 112 °C, forming a solid–liquid mixture; further heating to 240°C led to complete melting. Upon cooling, the melt transformed into a solid–liquid mixture, from which the coordination polymer was gradually recovered at ambient temperature. Rapid cooling (>200°C s−1) of the melt resulted in complete vitrification at −28 °C.