The stress-induced solid-state phase transition in the uniaxially-oriented poly (tetramethylene terephthalate)-poly (tetramethylene oxide) block copolymers has been investigated at room temperature by X-ray diffraction and infrared and Raman spectroscopy. The phase transition in the hard crystalline region has been found to occur broadly over wide stress and strain region. The small-angle X-ray scattering measurement showed that, as the sample is stretched, a new meridional scattering is observed in addition to the original one, indicating a very heterogeneous structural deformation within the sample. The phenomenon has been considered to originate from the broad distribution of the hard segmental lengths in the multi-block copolymer samples.

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Effects of static electric field and moisture upon the electrification of pressure-sensitive adhesive paper and the surface potential at different places on the paper were studied. The surface potential at the end portion of the release-coating after completion of peeling increased with an increase in static electric field and had a maximum at about 60% relative humidity RH in the curve plotted against RH. It was shown that the width of the positive surface potential distribution at the end portion of the peeled release-coating reflects the distribution of the electric charges on the face-stock and depends on the magnitude of the electric capacity of the face-stock. On the basis of these and previous results, a mechanism is proposed for the electrification phenomenon of pressure-sensitive adhesive paper under peeling. The fact that the signs of surface potentials are different at the starting and end portions of the peeled surfaces could be accounted for in terms of induced electric polarization. A satisfactory agreement was obtained between the calculated and observed values of the surface potentials on the face stock.

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Thickness of diffusional boundary layer (δD) on a cellulose membrane was estimated by means of multiple membrane layer method using non-ionic diffusants. The values of δD estimated under a good stirring were 0.9-2 and 0.4-0.6×10^-3cm at 80 and 30°C, respectively.
Rates of dyeing (or desorption) of non-ionic dyes on nylon 6 and polyester yarn were determined carefully. Comparison of rate of dyeing curves determined with those calculated by Hill's equation revealed the presence of a sorption delay in the dyeing. The delay decreased significantly as the rate of stirring of dyebath was increased. The delay was attributed to the resistance to transport of dye across the diffusional boundary layer surrounding the fiber.
Newman's equation, theoretical formula to express the rate of dyeing with the delay was used to calculate theoretical rate of dyeing curve. Boundary layer parameter (L) and diffusion coefficient of dye in fiber (D_f) were estimated by fitting the calculated curve to the experimental one. Values of δ_D estimated under a good stirring ranged in 1.3-4.4×10^-3cm. These results obtained revealed that the sorption delay due to diffusional boundary layer is inevitable in dyeing of fiber assembly even if a good stirring is made, particularly for the dyes with high affinity or large D_f.
Effect of temperature on the barrier action of diffusional boundary layer is discussed briefly.

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The activity coefficients of disperse dyes, such as azobenzene (AB) and p-hydroxy-p'-phenylazoazobenzene (HP), in alcohols having a series of alkyl groups (methyl to n-butyl) were determined by means of isopiestic measurements at concentrations from 2×10-³ to 2× 10-² mol kg-¹ at 40°C. It has been found that the activity coefficients of AB and HP were smaller than unity, and decreased with increasing carbon number of alkyl groups of the alcohols used as solvents. The coefficients of AB were smaller than those of HP. The results has been interpreted on the basis of the interactions between dye and alcohols.

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The equilibrium dye uptake and the rate of dye uptake by irreversibly supercontracted Lincoln wool-fibers were examined and were compared with those by the intact and extended fibers. These experimental results were discussed in terms of the structural transformation of α-crystalline structure to disoriented β-structure of wool fiber
The X-ray pattern indicated that the supercontraction occurred accompanying the transformation of the original oriented α-structure to disoriented β-structure of the microfibrillar keratin.
The structural transformation led to an increase of dye uptake and facilitated the dye diffusion in the bulk phase of the fibers. The increases of both the equilibrium and the rate of diffusion are attributable to the destruction of the original oriented α-structure of the microfibrillar keratin accompanying breakdown of the crosslinks between the microfibril-matrix interface.
The order of the extent of the equilibrium dye uptake and the rate of dye diffusion were supercontracted > extended > intact wool fibers.

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The membrane potential and permeability of charged cellulosic membrane in alkaline metal salts solution were determined at 25°C. The membranes used were carboxyethyl cellulose (CEC), sulphoethyl cellulose (SEC) and phosphorylated cellulose (PC) with the same degree of substitutions. The membrane potential and permeability as a function of the salt concentration were analysed by means of TMS theory.
In a series of alkali metal chlorides the diffusion coefficients of cations in membranes decrease with increasing Stokes radius of the cations. On the other hand the diffusion coefficients of chloride anion which is the common counterion species increase with increasing Stokes radius of the cations. In the case of sodium salts carrying different counter anion, i.e., NaCI, NaNO₃, and C₆H₅SO₃Na, the larger the ionic sizes the diffusion coefficients of anion decrease. While the diffusion coefficients of sodium ions in these salts are approximately the same value.
The effective fixed charge density and the diffusion coefficient of ions in the membranes increase in a sequence of CEC<SEC≤PC membranes. These results are explained by considering the counterion binding by the negatively charged groups in the membranes.

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Rayon fibers with and without treatment of a mixture of ammonium sulfate (AS) and diammonium hydrogen phosphate (AP) were heated in a nitrogen atmosphere to various temperatures from 400 to 1000°C, and subsequently activated with steam at that temperature.
The surface area and the adsorption capacities for benzene and iodine were measured of the activated carbon fibers and of the original ones.
From the precursor treated with AS-AP, highly adsorptive carbon fibers were obtained by steam activation at 900 and 1000°C; the surface areas were between 1500 and 1800 m²/g; the adsorption capacities were 40 to 60% for benzene and 2000 to 2300mg/g for iodine. It was found furthermore that those carbon fibers were obtained with higher yield than the ones from the untreated precursor.
Therefore, the treatment with a mixture of AS and AP can be effective to give excellent adsorptivity to the resultant carbon fibers at high yield.

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The grafting of acrylic acid and methacrylic acid made poly (ethylene terephthalate) (PET) fibers hydrophilic, and Na salt form of the grafted PET showed eminent hygroscopicity and water absorbency, as reported previously. In this report, water transfer behavior of the grafted PET (Na salt form) was investigated in comparison with conventional hydrophilic fibers.
The water absorption and the water release of the grafted PET were almost similar to that of the surface modified hydrophilic PET. The amount of absorbed water measured under a load was higher than that of cotton, and the velocity of water release was faster than that of cotton.
It was considered that the grafting took place in the amorphous region of PET and formed the hydrophilic domains in a hydrophobic matrix. So, in the moisture absorbing or desorbing process of the grafted PET, some specific behavior was expected in comparison with a conventional hydrophilic fiber such as cotton. However, it became clear that the time dependence of moisture absorption and desorption of the grafted PET were also similar to that of cotton.

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