Multiresponsive Supramolecular Gel Based on Pillararene-Containing Polymers

A multiresponsive supramolecular gel was constructed based on a bis(pyridinium) dication guest and a copolymer with pillararenes as the pendant groups, which was synthesized by free radical copolymerization of methacrylate-functionalized pillararenes and methyl methacrylate. The mechanism of gel formation was explored by the intensive study. Upon addition of competitive host or guest molecules, pillararene-based gel could be transferred into sol due to the competition of host–guest complexation. Surprisingly, the ordered stacking of pillararenes was indispensable to obtain the supramolecular gel, which endowed the system with response to temperature change.