In the present study, removal of rust stain from silk and cotton fabrics using thioglycolic acid(TGA)that has reducing and chelating properties, was examined in supercritical carbon dioxide(scCO₂). The scCO₂ especially including co-solvent was expected to act as a medium carrying the TGA into and TGA-Fe complex out from the fabrics without damaging them. The rust artificially prepared on cotton and silk woven fabrics were significantly extracted by the treatment with TGA in water and partially in methanol, though replace with scCO₂ resulted no cleaning. Addition of co-solvent such water and ethyl acetate in scCO₂ made the fabric white by removing rust. However reduced iron was re-oxidized and the fabric was colored in brown by this ‘batch method’. Therefore, the fabric was washed in a mixed fluid of methanol and carbon dioxide after ‘batch method’. This method was called ‘batch/post-washing method’, which led to reduction and no re-oxidation.

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Cyanuric chloride-immobilized cotton fibers were prepared by treatment with cyanuric chloride in benzene followed by immersion with alkali. Surface characterization of the surface-modified cotton fiber was carried out by means of ATR-FTIR spectroscopy. Reactivity of active chlorine in cyanuric chloride moiety immobilized on the cotton fibers was evaluated by reaction with the amino group-containing compounds in both aqueous and non-aqueous systems. An acidic dye to the water-soluble amino group-containing compound and the alkylamines to water-insoluble amino-containing compound were used. In the aqueous system, it was found that substitution reaction of active chlorines with an amine group and the active chlorine proceeded remarkably under acidic conditions rather than under alkaline conditions. It was also suggested that two of chlorine atoms of cyanuric chloride immobilized on fibers did not exhibit stepwise sequential reaction which is common for low-molecular cyanuric chloride derivatives. Furthermore, after the reaction under acidic conditions, activity of the unreacted active chlorine is remained.This indicated that the chlorines were not consumed by a reaction with water. On the other hand, it was found that if the surface-modified fabrics were treated with different water-insoluble alkylamines, their fabrics demonstrated a good water repellency. This indicates that the active chlorine reacts with the amino group easily even in benzene. The degree of water repellency can be controlled by the alkylamine concentration in the non-aqueous media. Taking into consideration these results, it was concluded that the cotton fibers which have been treated with cyanuric chloride may be reacted sequentially with wide variety of water-soluble and/or water-insoluble amino group-containing compounds.

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In this article we prepared an amphiphilic peptide, (_L-Leu-_L-Lys)8, grafted poly(N-isopropylacrylamide)network membrane. The graft content of the peptide and the content of the cross-linker were 4% and 16%, respectively. We investigated the permeability of _L- and _D- phenylalanine through this membrane. The pH- and thermo-induced permeability changes of the network membrane were observed. Under the neutral condition(pH 6.5 and 20℃), the peptide grafted PNIPAm network membrane showed a significant difference between the permeability of L-phenylalanine and D-phenylalanine. The maximum permselectivity(α=2.6)was achieved under this condition. At temperatures above the LCST of PNIPAm, PNIPAm polymers become hydrophobic; hence, the membrane shrunk. And under these conditions the permeable path for _L- and _D- phenylalanine was formed in the membrane which results in the non-permselectivity through this membrane.

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