Find in Library

Supramolecular polymer formed by non-covalent interactions between complementary building blocks entraps solvents and develops supramolecular polymer gel. A supramolecular polymer gel was prepared by the heating-cooling cycle of <i>β</i>-cyclodextrin (<i>β</i>-CD) and naphthalenedimide (NDI) solution in N,N-dimethylformamide (DMF). The host-guest inclusion complex of <i>β</i>-CD and NDI <b>1</b> containing dodecyl amine forms the supramolecular polymer and gel in DMF. However, <i>β</i>-CD and NDI <b>2,</b> having glutamic acid, fail to form the supramolecular polymer and gel under the same condition. X-ray crystallography shows that the alkyl chains of NDI <b>1</b> are complementary to the hydrophobic cavity of the two <i>β</i>-CD units. From rheology, the storage modulus was approximately 1.5 orders of magnitude larger than the loss modulus, which indicates the physical crosslink and elastic nature of the thermo-responsive gel. FE-SEM images of the supramolecular polymer gel exhibit flake-like morphology and a dense flake network. The flakes developed from the assembly of smaller rods. Photophysical studies show that the host-guest complex formation and gelation have significantly enhanced emission intensity with a new hump at 550 nm. Upon excitation by a 366 nm UV-light, NDI <b>1</b> and <i>β</i>-CD gel in DMF shows white light emission. The gel has the potential for the fabrication of organic electronic devices.