Polyethers and polyesters having methoxybenzalazine units with hexamethylene (C₆) and octamethylene (C₈) groups were synthesized from vanillin, which is one of the oxidative products of lignin. The thermal properties, mainly featured in the isothermal crystallization of these polymers, were investigated by differential scanning calorimetry (DSC).
Each polyether showed an exothermic peak in a cooling curve from the molten state. Isothermal crystallization from the molten state was observed in DSC measurements. The Avrami's indices obtained from the isothermal crystallization were about 4, suggesting that the crystals grew three-dimensionally. It was observed in the qualitative measurements using a polarizing microscope that crystals grew spherically.
Each of the as-polymerized sample of polyesters showed an endothermic peak of melting in a heating curve of DSC. Among the polyesters, C₈ derivative showed an exothermic peak of cold-crystallization during heating from the glassy state. The polyesters did not show isothermal crystalli-zation from the molten state. However, the polyesters crystallized isothermally from the glassy state. The results of kinetic analysis of C₈ derivative suggested that the crystals grew two-dimensionally.

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Interrelationships between optical properties and layered structure of pulp sheets were discussed quantitatively by applying the layered model theory developed by Scallan and Borch.
The number of optically-effective layers in the sheet, determined from optical data was a good structural parameter which relates optical properties to the layered structure of the sheet. For the sheets from pulps of different grade of bleaching, the values of the number of layers conveniently estimated from their specific scattering coefficient and basis weight coincided with those obtained from stepwise computer calculation by applying the layered model theory.
It is found also that the number of effective layers for diffusely incident light is practically affected by two geometrical parameters of the sheet, the number of fibrous layers in the z-direction and the degree of orientation of fibrous layers to the plane of the sheet.
Fairly good agreement in the number of optically-effective layers estimated from optical data and from cross sections of the sheet was obtained experimentally.

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An investigation has been done to study the binding state of disperse dyes in poly(ethylene terephthalate) (PET) substrate. Ten anthraquinone derivatives were employed as models for disperse dyes. The equilibrium amount of sorption of these compounds on PET film was determined by vapor phase dyeing in sealed glass tubes. From these results, the heats of sorption were calculated. If necessary, the values were corrected by using the p-nitroaniline accessibility, and compared with the heats of sublimation.
From the results it was found that the main interaction between the dye molecules and PET substrate is the dispersion force and that, in the cases of the dyes having proton-donar groups such as 2-hydroxyanthraquinone, hydrogen bonding plays also an important role.

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Modification of poly(ethylene terephthalate) (PET) fabric with low temperature oxygen plasma has been studied. Prior to the plasma modification, the fabric was treated with a strongly-interacting solvent, dimethylformamide (DMF). The effect of the prior DMF treatment on the subsequent plasma treatment was examined. The plasma-treated sample was characterized by X-ray photoelectron spectroscopy and viewed under a scanning electron microscope. Also wettability and loss in weight after plasma treatment were measured. The oxidative functionalization, surface roughness, and wettability are significantly larger for the sample which has received DMF treatment prior to the plasma treatment than that treated solely with the plasma. Furthermore, DMF-treated PET is much more subjected to etching after plasma treatment than the DMF-untreated sample and hence the weight loss of the former sample is larger than that of the latter one. DMF followed by plasma treatment leads to significant effect on the surface morphology. DMF-induced plastisization in PET causes a marked influence on the subsequent plasma modification.

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Azonia betain dyes 2a_??_2c and 4-nitroanilines, 3 and 4, were used as solvatochromic indicators to investigate the behavior of water in organic solvents. The shift of the wavenumber of maximal absorption of these dyes by an addition of water in organic solvent was analyzed by assuming that water and solvent molecules selectively solvate a solute in Onsager cavity. It was considered that water around the dyes, 3 and 4, in aprotic solvent such as acetone or acetonitrile constitutes a cluster or other associated species, while water in a small amount solvates unimolecularly the azonia betain dyes in aprotic solvent. Solvatochromism in a binary mixture of solvents was discussed by using a selective solvation model.

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Heats of adsorption (ΔH°_d) of series of 4-Aminoazobenzenes (4AABs) on cellulose from the aqueous solutions were determined, and the relation between ΔH°_d and the dipole moments (μ) of 4AABs was discussed; ΔH°_d values were regarded as the measure of the dye-fiber bond energy.
The results obtained showed that ΔH°_d decreases with an increase in μ, i.e. the dye-fiber bond energies increase with μ. This fact indicates the contribution of dipole force of the dye to the adsorption on cellulose.
The fact can be interpreted by the difference in region in cellulose, on which the dye or water molecules are adsorbed; the dye molecules are adsorbed on a region, water molecules are absent.

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Diffusion and reaction behaviors of monochlorotriazinyl reactive dyes in cellulose were investigated. Their dyeing properties were revealed on the basis of the diffusion theory accompanied by the simultaneous chemical reaction in terms of three parameters, the surface concentration, C₀, of active species, the diffusion coefficient, D, and the rate constant, K_c, of the pseudofirst-order chemical reaction with cellulose. By minimizing the weighted residual sum of squares for the experimental and theoretical diffusion profiles of active and fixed species, the values of three parameters were determined. The experimental profiles of the active and fixed species, obtained by the method of cylindrical cellophane film roll, agreed well with the theoretical ones of active and fixed species. It was generally confirmed at 75, 80 and 85°C that the values of D and C₀ were almost constant over the range of pH6.8 to 11, and that the hydrolysis in cellulose was negligible below pH10.5.

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Nickel salt of 4, 4′-bisacetamidostilbene-2, 2′-disulfonic acid (BAAS-Ni), stilbene-florescent dye containing intramolecular singlet-oxygen quenching group, has been synthesized and its effects were examined on the photofading of some dyes in solution and on a solid with a UV irradiation. The rates of photofading of indigoid dye (C. I. Acid Blue 74) and anthraquinoid dyes (C. I. Acid Blue 45 and C. I. Acid Green 25) were accelerated in the presence of BAAS-Ni, but that of Rose Bengal (C. I. Acid Red 94) was retarded remarkably. The effects of added Nickel p-toluene-sulfonate and the Nickel salt of sulfonic acid of dyes on the photo-stability of dyes were also examined.

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A photoresponsive polypeptide has been prepared by condensation reaction of poly (L-glutamic acid) (PGA) with pararoseaniline (Rose) in dimethylformamide solution (Rose-modified PGA). The Rose side chains in the polymer exhibited the photo-ionization under uv light irradiation, yielding triphenylmethyl cations, which vanished completely in the dark. The helix content of Rose-modified PGA, 4.3% in the dark, was increased to 7.2% by uv light irradiation at pH9.7, owing to the compensation for carboxylate anion (glutamic acid side chain) repulsions resulting from the production of the triphenylmethyl cation on the polymer chains by uv irradiation. The photo-induced changes of the conformation of Rose-modified PGA at pH9.7 were reversible and in correlation with the change in absorbance at 560nm of Rose side chain groups. On the other hand, the Rose side chains in the polymer exhibited no photo-ionization under uv light at pH5.7, owing to the neutralization effect in the low pH aqueous solution. As a result, uv irradiation did not induce any variations in conformation of Rose-modified PGA at pH5.7.

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Fracture surface morphology of spherulitic PBFP films has been studied by scanning electron microscopy. Onion-like cospherical aggregates are obtained in THF solution cast films. This morphology changes to that of irregular shaped crystalline platelets after melting and crystallization. The striations originally associated with chain axis direction of PBFP crystals have been observed on the fracture surface by employing ion ethching technique. From this it can be concluded that [c] axis direction is perpendicular to the spherulite radius.

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β-galactosidase from E. Coli was immobilized on three kinds of poly (vinyl alcohol) super fine fibers (SFF) carrying a different functional group. Dimethylaminated SFF (D-SFF) and trimethylaminated SFF (T-SFF) were found to adsorb the enzyme much more than sulfonated SFF (S-SFF). Optimum pH, optimum temperature, and thermal stability of the enzyme were negligibly affected by immobilization. β-galactosidase from E. Coli immobilized on D-SFF retained the activity for a longer period than the enzyme from jack bean bound on S-SFF. D-SFF is found to be the excellent support for immobilizing β-galactosidase from E. Coli and is expected to be applied to a continuous enzymatic reactor.

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Microcrystalline cellulose powder for column chromatography was treated with N, N′-bis (2-chloroethyl) piperazine or N, N′-bis (2-hydroxyethyl) piperazine and epichlorohydrin in the presence of sodium hydroxide solution. Bovine serum albumin adsorption capacity of the products was examined and compared with that of commercially available diethylaminoethyl cellulose.

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The chemical modification of chitosan by N-acylation of the amino groups with various carboxylic anhydrides was performed to introduce a new functionality. The equilibrium sorption of tryptophan by the N-acylated chitosan gels was determined at 30°C. The N-dodecanoyl derivative has a lower equilibrium sorption as compared with the original chitosan resulting from the more compact structure of the gel. On the other hand, the N-octadecanoyl derivative, which can not form a compact structure due to a longer side chain, has a higher sorptivity of tryptophan. The N-octadecanoyl chitosan gel having a degree of substitution of 0.45, selectively sorbs L-tryptophan from an aqueous 1:1 D, L-tryptophan solution of 1.015×10^-2 mol•dm³ giving a ratio of sorption of L/D ≈60.

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