Novel Synthesis of Single- and Double-Cyclic Polystyrenes by Electrostatic Self-Assembly and Covalent Fixation with Telechelics Having Cyclic Ammonium Salt Groups

A novel telechelic polystyrene having moderately strained cyclic ammonium, i.e., six-membered bicyclic quinuclidinium salt groups, has been synthesized, and mono-, di-, and tetracarboxylate counteranions were introduced by the ion-exchange reaction. A monocarboxylate, i.e., benzoate, counteranion was found to cause a selective ring-opening reaction of the quinuclidinium salt end group by the heat treatment at 110 °C. A single-cyclic polystyrene 2 was then produced in a high yield from the polymer precursor carrying a dicarboxylate, i.e., terephthalate, counteranion by the heat treatment in a diluted (0.1 g/L) toluene solution. Furthermore, a double-cyclic (8-shaped) polystyrene 3 was produced relevantly from another precursor carrying a tetracarboxylate, i.e., tetrakis((4-carboxylatophenyl)oxymethyl)methane, counteranion.