A bisporphyrin cleft molecule with a trinitrofluorenone moiety assembled to form supramolecular polymers through a head-to-tail host-guest interaction. Bispyridine derivatives work as interchain cross-linkers among the supramolecular polymer chains. The supramolecular networked polymers showed characteristic solution viscosity that revealed the formation of the entangled supramolecular polymers. Viscoelastic spectroscopy established that the supramolecular polymers resulted in well-entangled solutions with associating and networking polymers. Morphological transition of the supramolecular polymers was given by AFM images. The non-cross-linked polymer gave rise to wide-spread thin networks while the cross-linked networks resulted in thicker worm-like nanostructures. The supramolecular networks gelled in 1,1,2,2-tetrachloroethane, and an elastic free-standing film was fabricated with a Young's modulus of 1 GPa.

In this presentation, I will describe the synthesis and characterization of newly developed supramolecular porphyrin polymer, and macroscopic features.

1)    Kinjo, K.; Hirao, T.; Kihara, S.-i.; Katsumoto, Y.; Haino, T. Angew. Chem. Int. Ed. 2015, 54, DOI: 10.1002/anie.201508475.