A cellulosic derivative (Cell-ox-sp) containing both chelating functional 8-hydroxyquinoline (ox) and photoresponsive spiropyran (sp) moieties was synthesized and photoregulation of metal ion-adsorption of Cell-ox-sp was examined. Reaction of powdered cellulose with 5-chloromethyl-8-hydroxyquinoline gave cellulosic derivatives with degree of substitution (DS) by ox up to 1.1, and subsequent reaction of the products with a spiropyran derivative containing carboxyl group did Cell-ox-sp with DS by sp of about 0.5. In the reaction sequence, metal ion- adsorption of the each product increased from cellulose to Cell-ox and considerably decreased from Cell-ox to Cell-ox-sp. Under irradiation with UV light, Cu2+- adsorption of Cell-ox-sp considerably increased and under subsequent irradiation with visible light it decreased as it had been before. These substantial changes in Cu2+- adsorption may suggest that ox moiety and merocyanine type sp moiety yielded with UV light irradiation co-operatively adsorbs Cu2+. Adsorption of Zn2+ showed similar behaviors under irradiations with UV light and with subsequent visible light, but the extent of the change was lower than that for Cu2+. These results show that metal ion-adsorption of Cell-ox-sp may be photoregulated under irradiation with UV light and visible light, possibly selectively in respect to ion species.
The photofading behaviors of azo disperse dyes on polylactide fabrics were investigated. The fabrics were dyed with 1% owf of 12 commercial dyes, whose chemical structures are known. When they were exposed to a carbon arc light source, their discoloration increased with increase in exposure time. The photofading behavior was proved to be correlated with the chemical structures. The dyes containing cyanoethyl or acetoxyethyl group as 4'-substituent, Disperse Red 50, Red 82 and Orange 30, showed high light fastness. Cyano or chloro group showed a positive effect on the light fastness, and methyl group did a negative one. The samples of Disperse Red 50 and Red 82 showed the highest light fastness grades, 4.19 and 4.00, respectively. Their light fastness depended on the amount of sorbed dye, and a deeper color fabric tended to have a higher light fastness than a paler color one. The light fastness of the fabric dyed with 0.01% owf of Disperse Red 50 was ca. 4 grade lower than that of 2% owf. The sample of Disperse Red 82 showed a similar dependence on the amount of sorbed dye, but the light fastness was not so strong in comparison with Disperse Red 50.
The photofading behaviors of anthraquinone disperse dyes on polylactide fabrics were investigated. The fabrics which had been dyed with 13 commercial dyes were exposed to a carbon arc light source. The polylactide fabrics dyed with Disperse Red 127 or Violet 26, which have phenoxy substituents, showed the light fastness higher than 4 grade. The dyes for acetate fabrics, Violet 1, Blue 3 and Blue 7, were not available for polylactide fabrics because of their large color change by light. Disperse Red 127 and Violet 27 on polylactide fabrics had the highest light fastness grades in them. Their light fastness depended on the amount of sorbed dye. The deeper color fabric tended to have a higher light fastness than the paler color one. However, in the case of Disperse Violet 27, the light fastness of the palest color fabric, which had been dyed with 0.01% ouf of it, was about 0.7 grade higher than that of 0.03% owf. When the polylactide fabric had been dyed with the mixture of Red 127 and Violet 27, the photofading behavior was retarded as compared with the individually dyed ones.
Melt-grown lamellar crystals of syndiotactic polypropylene were observed by cryogenic high-resolution transmission electron microscopy. Both the (200) and (020) lattice fringes were successfully recorded. The information about the stacking faults in the lamellar crystals was also recorded in the high-resolution images, as known from the streaked feature of the 020 reflection in the optical diffraction pattern. The processed image using a computer indicated that the persistent length along the b direction of the molecular layers divided by the faulted boundary is very large, and accordingly, the model structure of the stacking faults proposed by Lovinger et al. should hold for the observed specimens.