Unexpected LCST-type phase behaviour of a poly(vinyl thiazolium) polymer in acetone

We report on an unexpected lower critical solution temperature (LCST)-type phase transition of a poly(vinyl thiazolium) polymer in acetone solution, which was synthesized via radical polymerization of its corresponding ionic monomer bearing no thermoresponsiveness in acetone. The phase transition temperature can be conveniently varied by polymer concentration, ionic strength and addition of a cosolvent