Reversibly tunable lower critical solution temperature utilizing host-guest complexation of pillar[5]arene with triethylene oxide substituents.

A thermoresponsive macromolecule consisting of 10 outer triethylene oxide groups and a pillar[5]arene core was prepared. The macromolecule showed lower critical solution temperature behavior. Moreover, its clouding point can be reversibly tuned based on the addition of guest and host compounds; the clouding point increased upon addition of a guest didecylviologen salt and decreased when the competitive host cucurbit[7]uril was added.