A polyrotaxane, in which many β-cyclodextrins (β-CDs) are threaded onto a triblock copolymer of poly(ethylene glycol) (PEG) and poly(propylene glycol) (PPG) capped with fluorescein-4-isothiocyanate (FITC), was synthesized as a model of stimuli-responsive molecular assemblies for nanoscale devices. Coupling of FITC with the terminal amino groups in the polypseudorotaxane was performed in DMF at 5 °C. Under these conditions, a side reaction between the hydroxyl groups of β-CD and FITC was prevented. The interaction of the β-CDs with terminal FITC moieties in the polyrotaxane was significantly observed at low temperature. However, the interaction of the β-CDs with the PPG segment was observed with increasing temperature. On the basis of these results, it is concluded that the majority of the β-CDs move toward the PPG segment with increasing temperature although some β-CDs may reside on the PEG segments.

SUMMARY: A polyrotaxane in which many b-cyclodextrins (b-CyDs) are threaded onto a triblock copolymer of poly(ethylene glycol) (PEG) and poly(propylene glycol) (PPG) capped with fluorescein-4-isothiocyanate (FITC) was synthesized as a model of stimuli-responsive molecular assemblies for nanoscale devices. bCyDs threaded onto the triblock copolymer enhance the solubility of the polyrotaxane and presumably contribute to the prevention of aggregation between PPG segments. The interaction of b-CyDs with a terminal FITC moiety was observed to be significant at 10 8C, however, with increasing temperature, the interaction of b-CyDs with a PPG segment becomes prominent. From these results, it is concluded that the majority of bCyDs move toward the PPG segment with increasing temperature although some b-CyDs may reside on PEG segments.

A polyrotaxane consisting of many /kyclodextrins @-CDs) and a triblock copolymer of poly(ethy1ene glycol) (PEG) and poly(propy1ene glycol) (PPG) capped with bulky end-groups was synthesized as a model of stimuli-responsive supramolecules for nanoscale devices. The polyrotaxane was reversibly soluble-insoluble in water in response to temperature. This was achieved through the assembled and dispersed states of BCDs along the block copolymer. It is considered that intermolecular hydrogen bondings of [I-CDs, as well as the PEG segment length of the copoloymer. are predominant factors for regulating such thermally switchable behavior of the polyrotaxane.

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This work aims to increase the interface between anode and electrolyte in solid oxide fuel cells by controlling the 3D microstructure with a commercial ink-jet 3D printer. Anode and electrolyte inks suitable for use in a 3D printer were prepared by altering the viscosity and the droplet size. A porous anode structure that ensures a flow path for gases was achieved by addition of acrylic particles into the anode ink. A dense electrolyte structure that prevents leakage was created. The anode and electrolyte layers were produced as long, flat strips which were aligned in parallel to form sheets; these sheets were stacked orthogonally to complete the 3D microstructure called the ‘anode functional layer’. The anode functional layer was roughly 100 micrometers on a side with a thickness of 4 micrometers. The anode functional layer was inserted between the anode and electrolyte. The assembled solid oxide fuel cell showed high performance when tested at 600 °C with dry methane as the fuel source.