A triple-monomer methodology to construct controllable supramolecular hyperbranched alternating polymers

A novel D3-AC-E3 triple-monomer methodology was proposed to construct supramolecular hyperbranched alternating polymers. Two rigid homotritopic monomers tris(per-methylated pillar[5] arene) (D-3) and tris(benzo-21-crown-7) (E-3), and a heteroditopic monomer bearing a dialkylammonium salt and a neutral guest moiety, were prepared. The supramolecular hyperbranched alternating polymer was formed by selective binding interaction between the pillar[5] arene moiety with the neutral guest moiety and between the benzo-21-crown-7 group and the dialkylammonium salt group. The triple-monomer system was found to effectively avoid the formation of cyclic oligomers/gels/precipitates usually formed in the traditional A(2) + B-3 double-monomer system. This study will be helpful in designing supramolecular hyperbranched polymers with controllable structure and function.