After sufficient degradation of acetylcelluloses with degree of substitution (DS) from 0.58 to 1.08 by cellulase, glucose as well as monomers, dimers, trimers, and oligomers of acetylated saccharides were detected in their hydrolysates. The amount of liberated glucose was rather close to the number of unsubstituted glucose units in the molecular chains, estimated theoretically by Timel's method. The extent of enzymatic hydrolysis of the substrates was decided by the number of unsubstituted glucose units in their molecules. In the case of the acetylcellulose with DS=1.56, no chain cleavage was observed. Consequently it was found that cellulase can interact with unsubstituted glucose units in the acetylcellulose and cleaves β-1, 4-glucosidic bond attached to unsubstituted glucose unit.

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Phosphate esters of calix_??_4_??_resorcinarenes having four alkyl chains (_??_4_??_Ar-R_n (P)) were prepared and examined as auxiliaries for dyeing of nylon 6 fiber with a disperse dye (KPLR). The dyeing with_??_4_??_Ar-R_n (P) was effective and the dye uptake was 40% more than that with a commercially available disperse agent (Disp-TL). The dyeing at 80°C and 95°C gave 10% and 25% higher dyeability respectively, as compared with the dye uptake using phosphate esters of monododecylresorcinol (M-R₁₂ (P)). The maximal dye uptakes were obtained with 1-2g/dm³ of_??_4_??_Ar-R_n (P), and with 12g/dm³ of Disp-TL. respectively. The effect of_??_4_??_Ar-R_n (P) on the level dyeing was confirmed by the observation of the cross section of dyed fiber.

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The effect of poly (ethylene glycol) (PEG) on the dyeing properties of vinylon fiber with a milling acid dye, Kayanol Milling Red RS 125 (C. I. Acid Red 114), has been investigated in dye-PEG-sodium chloride aqueous solutions at 80 and 90°C. Each dyeing was made in a finite bath (liquor ratio 1:1, 500) with1×10^-4 mol/L of the dye in the presence of 0.1mol/L of sodium chloride. The reduced viscosities of dye-PEG (0.1g/dL) aqueous solutions increased with increasing dye concentrations and showed a maximum value. The absorption maximum (λ_max) of the dye shifted to shorter wavelength and the equilibrium sorption of dye (C_∞) gradually decreased with an increase in the concentration and weight-average molecular weight (_??__W) of PEG. The results are attributed to dye-PEG complex formation. The Apparent diffusion coefficient (D) and apparent rate constant (K) of dyeing varied in an opposit tendency from C_∞

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The relation between the pressure-dependence of water absorption and the compression characteristics of cotton fabrics, and the changes in the water absorption of the fabrics by the treatment of a softener, thickener, or a mixture of them were investigated. The initial water absorption rate of the cotton fabric increased with the pressure, and was equilibrated at 626 Pa or above. The compression ratio also increased with the pressure, reached about 25% at the pressure of 626 Pa, where the initial water absorption rate was eqilibrated, and continued to increase after this point. The time needed for the saturation of water was shortened with the increase in the pressure, showing the peaks of the saturation of water at the pressure of 210 Pa and 349 Pa. No changes were observed in the compression-characteristics of the fabrics with the treatment of the finishing agents (softener, thickener or the mixture of them) or with the treating times. However, the amount of absorbed water at 626 Pa showed the most decrease in the fabric treated with a softening agent of the all finishing agents examined. The amount of absorbed water was increased in the fabric treated with a thickening agent compared with the untreated fabric when the treating time was 2 minutes or longer. Changes in the amount of absorbed water with the treating time was smallest in the fabric treated with a mixture of the softener and the thickener.

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Applying of plasticizer effect of water and acrylonitrile (AN) on Polyacrylonitrile (PAN) for AN polymerization in melt state, continuous PAN polymerization and direct spinning of the PAN melt was studied. The product, porous fiber, was found to be used as “synthetic rush for TATAMI” through modification of polymer composition, molecular weight, spinning conditions such as drying, drawing, and surface treatment. The product still contains residual AN though the content is less than Ippm, future work is needed to diminish the residual AN completely.

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The direct reaction of ethylene oxide with trioxane was thought impossible because of the weak basicity of trioxane. Thus, as the initiation mechanism of the copolymerization of trioxane and ethylene oxide, the formation mechanism of dioxolane from ethylene oxide and formaldehyde was proposed by several authors, and this mechanism was thought plausible for a long time.
We found a new reaction, that is, the direct reaction of ethylene oxide with trioxane and isolated a novel cyclic formal. From this novel cyclic formal, 1, 3, 5-trioxepane was formed and then dioxolane was also generated. A new intermediate, or a novel cyclic compound, was separated using a micro-distillation apparatus. Its chemical structure was confirmed using ¹H-NMR, ¹³C-NMR, Mass spectrum and elemental analysis. The new isolated intermediate or novel cyclic compound was 1, 3, 5, 7-tetraoxacyclononane, which identifies a new direct reaction between trioxane and ethylene oxide. This reaction identified the precise initiation mechanism of the copolymerization of trioxane and ethylene oxide.

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The decreased dyeability of the polyamide fibers whose amino terminal groups were triazinylated was studied. The terminal modification could be performed by the “reactive spinning” method in which polymer pellets of Nylon-6 (Ny6) and 1, 3, 5-triphenoxy-2, 4, 6-triazine (TPT) were directly reacted during melt spinning. When the TPT to Ny6 ratio in feed was less than 1.5 wt%, the polymer viscosity and tensile properties of the resultant modified fibers were even higher than those of the original Ny6 fiber (control). Due to the high level of triazinylation of N-terminuses of Ny6, the dyeability of the modified fibers became one tenth compared with that of the control fiber. Since the dyeability was controlled by the amount of TPT added, this technique can possibly be applied to the separate dyeing of polyamide fibers in one pot.

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