Supramolecular Polymer Networks Based on Calix[5]arene Tethered Poly(p-phenyleneethynylene)

A poly(p-phenyleneethynylene) polymer (PC[5]), featuring two pi-rich cone-like calix[5]arene cavities (assembling cores) connected to a rigid p-phenyleneethynylene spacer, was synthesized by a Pd-catalyzed cross-coupling reaction. NMR investigations provide support for the self-assembly dynamics of PC[5] (homopolytopic host molecule) and complementary 1,10-decanediyldiammonium (C-10) guest in solution in the construction of supramolecular polymer networks. Upon variation of the host/guest molar ratio, two distinct types of assemblies were identified in solution: a 1:2 bis-endo-cavity assembly C-10 subset of PC[5]superset of C-10 (PC[5](cap)) and a polycapsular polymer network assembly PC[5]superset of C-10 subset of PC[5] (PC[5](net)). The reversibility of the assembly/disassembly processes of PC[5](net) and PC[5](cap) upon successive additions of Et3N and TFA was also investigated. AFM analysis of PC[5](net) revealed the formation of a homogeneous continuous network on, surface.