The interaction of water molecules with textiles was investigated by analyzing the moisture sorption isotherm in terms of thermodynamic parameters as well as the parameters of Brunauer, Emmett and Teller (B. E. T.)'s multi-layer adsorption model or Hill's multi-molecular adsorption model of water cluster formation for a series of natural polypeptide and synthetic polyamide fibers. The investigation was further proceeded by a broadline proton NMR spectroscopy to discuss the interaction more directly by molecular parameters than by the parameters basing on the physico-chemical and physical models.
The following conclusions were obtained to characterize the interaction: (i) From temperature dependence of the moisture sorption isotherm, the differential heat of moisture sorption and, subsequently, the excess energy (entropy decrease relative to bulk water) were estimated for scoured wool and nylon 6 fibers as a function of relative humidity at a given temperature of 30°C, validating the concept of rather regular structure of sorbed water in the B. E. T. multi-layer adsorption model or the Hill's multi-molecular adsorption model of cluster formation. (ii) From the analysis of sorption isotherm of the polypeptide and polyamide fibers in terms of the B. E. T. parameters, n_max, the maximum number of layers below which the calculated sorption isotherm is closest but never exceeds the observed isotherm, is found to be 6 for almost every specimen tested. The molar concentration of monolayer-adsorbed water (Langmuir's adsorption) normalized by the degree of noncrystallinity, [V_m/(l-X_x)], is found to increase gradually at first and then rapidly with increase in the molar concentration of [CONH] groups in the back bone chain for a series of aliphatic nylons including a scoured silk, but excluding the scoured wool and an aromatic polyamide fiber, Kevlar 29; i.e., the denser the distribution of [CONH] groups along the back-bone chain, the greater is the water adsorptive capacity per [CONH] group. (iii) The narrow linewidth ΔH_n in the broadline proton NMR spectrum exhibits a transition at a certain moisture regain at which the sorbed water changes in its nature from layered-adsorbed water with the number of layers up to n_max to less interacted water with the number of layers of n>n_max, but not to an extent of far less interaction as comparable to the water in liquid state; i.e., the so-called bulk water.

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Limiting Young's modulus along the chain direction has been calculated based on the lattice dynamical theory for the several rigid-rod polymers: 371.0 GPa for poly-p-phenylene benzobisthiazole (PBT) (macroscopic modulus ca. 250 GPa), 275.1GPa for poly-p-phenylene, 588.3GPa for poly-pbenzobisthiazole, and 505.3GPa for poly-p-phenylene pyromellitimide (macroscopic modulus ca. 130GPa). The difference in the Young's modulus among these polymers has been discussed based on the atomic displacements and potential energy distribution calculated for the tensile deformation of the chains. Tentative band assignments of the infrared and Raman spectra of PBT were made in order to check the propriety of the force field used in the above calculation.

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The state of water in the liquid silk from Bombyx mori was investigated as a function of moisture regain with drying. In the case of the drying by the heat treatment, the nuclei of silk I type crystal were formed at moisture regain of 65 wt% by the drying at room temperature, while by drying at 50°C, those of silk II type crystal were formed at lower moisture regain (55 wt%) than those of silk I. In these cases, the bound state of water was weakened suddenly, and then the crystal grew.
The liquid silk was also immersed into the aqueous solution of acetic acid and then dried. The relationship between the bound state of water and the formation of crystal was similar to the case of the formation of silk II type crystal.

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Photodegradation behaviors of some glassy polymers as polystyrene (PS), poly(methyl methacrylate) (PMMA), styrene-methyl vinylketone copolymer [P(St-MVK)] and methyl methacrylate-methyl vinylketone copolymer [P(MMA-MVK)] have been investigated in terms of some mechanical properties as tensile strength, elongation, flexure strength and flexure strain. The results obtained are as follows.
1) PS and P (St-MVK) have the same photodegradation tendency. However, the photodegradation of P (St-MVK) is so remarkable as to attain its limitation in about 15 days, while that of PS in about 2 years. The degradation was found to be the decrease of molecular weight by photo reaction because the polymer viscosity lowers in proportion to lowering of mechanical properties.
2) Mercury lamp irradiation is an effective method for the accelerative photodegradation test.
3) Mechanical properties of PMMA and P (MMA-MVK) do not deteriorate in proportion to lowering of molecular weight.
4) Blending of PS homopolymer and MVK copolymer can endow the photodegradabilities and change the photodegradation rate.
5) Photodegradation of MVK copolymer can be adjusted by the addition of the absorbent of ultraviolet rays.
6) The temperature has a great influence on the photodegradation. The activation energy of the degradation for P (St-MVK) is as low as for rubber.

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Poly(ethylene terephthalare) (PET) fibers blended with poly (ethylene oxide) (PEO) and sodium dodecylbenzenesulfonate (DSAS) were prepared by melt spinning at 280°C in order to make an antistatic modification of polyester fiber. The blend fibers as-spun were drawn by five times at 80°C and heat-treated at 140°C. Three PEO samples with molecular weight (M_n) of 4, 000, 10, 000, and 20, 000 were used. At a constant blend ratios of DSAS to PEO, both spinnability and drawability of the blend fibers were improved by increasing molecular weight of PEO. The fiber blended with 1.5wt% of PEO (M_n=20, 000) and 1.0wt% of DSAS had the optimum quality that was comparable to the control PET fiber. The antistatic property of these fibers was evaluated by half-life-time (t_1/2) of leakage of electrostatic charge at 20°C and 45% RH. The values of t_1/2 for the fibers before and after washing were in the range of 0.5-9.4sec and 3.4-11.5sec, respectively. Both values were much lower than those for the control PET fiber and the blend PET fibers containing PEO only. The higher the molecular weight of PEO, the higher the antistatic property of the blend fibers. The best property was attained with the fibers blended with 1.5wt% of PEO (M_n=20, 000) and 1.0wt% of DSAS. The tensile strength of the blend fibers was a little lower than that of the control PET fiber while the elongation became a little larger. The blend fibers had a Young's modulus higher than the PET fiber. From these results, the role of ionic surfactant DSAS is discussed in relation to the phase separation of PEO in the fiber matrix.

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The membrane potential and permeability of charged cellulosic membranes in tetraalkylammonium chloride solution were determined at 25°C. The membranes used were carboxyethyl cellulose (CEC), sulphoethyl cellulose (SEC), and phosphorylated cellulose (PC). The salts, tetraalkylammonium chlorides used were (CH₃)₄NCl, (C₂H₅)₄NCl, and (n-C₄H₉)₄NCl. The membrane potential and permeability as a function of the salt concentration were interpreted by means of the TMS theory.
The diffusion coefficients of ions in membranes are dependent on Stokes radius of the cations. As the radius increases, the diffusion coefficient of the cations decreases and that of the anion increases. The above correlations are expressed by the same curve for the case of alkaline metal salts.
The effective fixed charge concentration in the membranes increases with increase in Stokes radius of the cations, An anomalous value of the effective fixed charge concentration was obtained when calculated for the systems of SEC and PC membrane - (n-C₄H₉)₄NCl. The obstruction effect by the large ions is proposed in the interpretation of the findings using the TMS theory. The effectivity and the diffusion coefficient of ions in the membranes increase in a sequence of CEC<SEC<PC membranes.

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Among the factors which affect the adsorption efficiencies of the vapor phase components of cigarette smoke by activated carbon fibers (ACF), the effects of smoke temperature, TPM (Total Particulate Matter) and water vapor were evaluated. Even at the final puffing, namely 14th puff for a cigarette used, the smoke temperature was only 7°C higher than the ambient temperature. Therefore, it was recognized that the smoke temperature has practically no effect on the adsorption in the case of the cigarettes used in this work. The adsorption ability of ACFs for the vapor phase components, especially of those having narrow micropore radius, was extremely lowered by TPM. For ACFs having narrow micropores, even a slight difference in pore radius resulted in great difference in the adsorption efficiency. Among the components in the vapor phase, those having relatively high boiling points underwent more inhibition of adsorption than low boiling point components. It has been suggested, therefore, that ACFs behave as if their pore radii and specific surface areas become small. From the adsorption experiments of organic component vapor and water vapor, it was confirmed that the adsorbed amounts depend on pore radii rather than specific surface areas because there exist combinations for the maximum adsorption of smoke components. In the presence of water vapor, this combination indicated a considerable substitution of organic components by water. Water vapor had appreciable effects on the adsorption efficiency of ACFs.

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