Crystal orientation function, crystallite sizes and mechanical properties of drawn poly (ether ether ketone) (PEEK) filaments obtained by drawing amorphous unoriented filaments at temperatures from 20 to 280°C were investigated. The properties of filaments redrawn at 260 to 320°C after drawing at 145°C and 150°C (“two-step-drawn” filaments) were also examined. The degree of orientation increases with drawing temperature above 160°C and reached to the maximum value at 260°C. The maximum value of the crystal orientation function and the birefringence of amorphous region are 0.983 and 0.234, respectively. The largest value of tensile modulus of drawn filaments was 12.2GPa. Plots of amorphous compliance against birefringence of amorphous region showed a straight line, which have a large slope below the draw ratio of 2 and a small slope above the value of the draw ratio. The filaments redrawn at 260°C after drawing at 145°C showed almost the same values of the degree of crystallinity and orientation as the filaments drawn directly at 260°C. While the degree of orientation of amorphous region decreased with drawing temperature for the filaments drawing directly above 260°C, it increased up to 300°C for the “two-step-drawn” filaments. The number of crystallite in the filaments seems to affect the restriction of the amorphous regin.

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Effects of types of fibers and fabrics on the rate constant in the falling rate period in drying were investigated by the automatic measurement of drying process. It was found that the rate constant in the falling rate period (k₂) could be converted to the decreasing coefficient of evaporation rate (k) by using the following equation: k=k₂x_d/k_l where, x_d and k₁ were the dry fabric weight and the evaporation rate in the constant rate period, respectively. The light fabric showed the large k₂ value when the same fiber was used. The k₂ x_d value increased in the following order; wool, silk, cotton, nylon, acrylic, and polyester, and they dried faster in that order.

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The rate constant in the falling rate period of drying process was considered by assuming an equilibrium sorption condition in the materials. The rate constant, k, was expressed by the following equation: k=αn/Vo where, α, n and Vo were the coefficient determined by temperature and water vapor pressure, the constant in Halsey equation described the sorption isotherm, and the water regain after drying, respectively. The experimental k values were in good agreement with the calculated values for the natural fibers having small k values. In the case of synthetic fibers and low humidity which gave large k values, the experimental k values were smaller than the calculated ones.

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The uncertainty of the diffusion coefficient (D_θ) of glassy polymer film determined by the time-lag method (D_θ=l²/6θ), can be attributed to the relaxational behavior characteristic of glassy polymers. For glassy polymers, a surface concentration at one face of membrane is initially zero and reaches an equilibrium concentration exponentially. Fick's second law was solved under the boundary condition considering the time dependence of surface concentration and initial condition. Then, we obtained the total amount of penetrant diffusing through the membrane in time t. As t → ∞, this equation converges on the straight line. This line has an intercept on a t axis, which expresses the time-lag as a function of α(=βl²/D) indicating the time dependence of surface concentration. The time-lag method for the glassy polymer membrane was examined for different gases and different glassy polymers by using the equation obtained.

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Porous chitosan membrane was prepared by drying a mixed solution of chitosan and polyethylene glycol (PEG) in an oven at 50°C on a plate, followed by dialysis, and lipase was immobilized in the porous chitosan membrane with glutaraldehyde. The lipase immobilized in porous chitosan membrane obtained from the mixture of chitosan and PEG with the molecular weight of 20000 (1:1 in weight) had a high hydrolysis activity towards olive oil. The activity yield of the immobilized enzyme was as much as 64% of the native enzyme, and increased with decreasing membrane thickness. Much difference was found neither in pH nor temperature dependency between the activities of immobilized and native enzymes. The immobilized lipase in porous chitosan membrane retained about 180% of the activity at initial use after repeated use of 7 times.

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The effectiveness of tension control method is made clear by measuring the internal strain and the shape in end faces of the two yarn packages. One is formed according to the theoretical tension curve which makes the residual circumferential stress to be same for all yarn layers, and the other is formed under constant winding tension. Tension controller manufactured in this experiment can form yarn packages according to winding tension of arbitrary theoretical curve from the internal yarn layer to the external yarn layer. In the yarn package formed under controlled winding tension on the assumption that the degree of anisotropy in the nylon-6 yarn package is in the range from 0.36 to 0.50, bulge and cob-webbing of the eng faces of it are smaller than the yarn package formed under constant winding tension. The values and distributions of internal strain, and unwinding tension for the yarn package formed under controlled winding tension, are smaller than ones of the yarn package formed under constant winding tension.

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Alcaligenes faecalis cells were immobilized in calcium alginate gel beads and employed for production of chitosanase by repeated batch processes. The activity of the immobilized cells increased with extending the culture period, and reached a maximum, 3.6U/ml in 6 days. This value corresponded to about 1/3 of that of free cells. In repeated batch experiments the activity of the immobilized cells increased gradually in the early cycles, and it decreased slightly after the four cycle. Chitosanase was produced by the immobilized cells in an enzyme production medium containing 0.1% glucose, 0.5% peptone, 0.1% yeast extract, 0.1% KH₂PO₄, 0.02%MgSO₄•7H₂O, 0.1%NaCl, 0.5%CaCl₂•H₂O and 0.5% colloidal chitosan.

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