The spherulites formed on the gradually cooled polyethylene film were treated by low temperature plasma initiated from various gases such as argon, nitrogen, oxygen and carbon tetrafluoride. Observation by scanning electron microscope (SEM) showed that the surface morphology of spherulite was dependent on the kind of gases and treatment time. The most suitable condition for SEM observation was obtained by oxygen gas plasma treatment with the electric power at 200-300W and the treated time of 20min. The effect of low temperature plasma was different from that of chemical treatment by sulfuric acid.

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In accordance with the newly developed homogeneous periodate oxidation procedure, we prepared high cleavage level 2, 3-dialcohol cellulose (DAC) which gives off a clear and transparent film. Viscoelastic properties of DAC were investigated in relation to those of cellulose. Dynamic mechanical measurements for DAC at 110Hz over the temperature range from -150°C to 150°C revealed two kinds of relaxation processes, which were respectively centered around -70°C and 112°C. The first process at -70°C was related to dielectric relaxion, and was regarded to be, similar to the process in cellulose, due to the motion of methylol groups. On the other hand, the cleavage of C₂-C₃ bonds of the glucopyranose ring resulted in the process at around 112°C, while no comparable process has been reported for cellulose in the similar region. This process was ascribed to the micro- Brownian motion along the main chain. From the temperature variation of the stress-elongation diagrams, the glass transition temperature Tg for DAC was estimated to be about 80°C. The DAC film above Tg showed a marked elongation reaching 200% at 112°C.

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The mechanical properties of silk fibroin membranes were improved by mixing with a suitable amount of chitosan. The strength increased by 80%, while the elongation decreased to 60%. The change in mechanical properties was considered to be the result of the high orientation of molecules backed up by the strong hydrogen bonding between the molecules of chitosan and silk fibroin.

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Silk powders were prepared by freeze-drying of a silk fibroin solution, which was obtained by dialysis of an aqueous calcium chloride solution of silk fibroin. Silk powders were treated with formaldehyde or with water-solution urethane resin, and their properties were studied. The DTA results showed that the thermal stability of silk powders increased by the treatment with formaldehyde and urethane. The chemically modified silk powders were molded at 150°C under pressure. The molded silk powder had better water absorbing property than those of other resins. The wet strength of the molded formaldehyde-treated silk powders did not decline while a declining tendency was observed for the molded untreated silk powders.

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Wool fabrics were treated with butyl and phenyl isocyanates (designated as BI and PI, respectively) in N, N-dimethylformamide and the setting properties were studied by the IWS crease angle test with a Hoffman press or by a similar but handy method with a home steam iron. The results obtained by the two set methods agreed well when the fabrics were set without a reducing agent: both BI- and PI- treated fabrics gave temporary set values much higher than those of the control, but only a PI-treated fabric with a high add-on of 14% gave a high permanent set value and other samples were not permanently set. When fabrics were set under reducing conditions, all the fabrics gave high permanent set values with a Hoffman press, while BI- and PI- treated wool samples gave lower permanent set values than that of the control, when set with a home steam iron. Lincoln wool fibers were treated with BI and PI and the extention set with boiling water was also studied with the treated samples. The results of set experiments with the three different methods indicated that the introduction of hydrophobic groups by treatment with isocyanates, especially with PI, gave two different effects on the set values: the treated samples became more resistant to the diffusion of a reducing agent so that mercaptan/disulfide interchange reaction during setting was not enhanced as much as the interchange in the control, while the hydrophobic groups made the set of the samples more stable in hot water. Depending on the setting conditions under reducing conditions, the set values of the treated samples varied with the balance of the two adverse effects.

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A layered structure of the paperboards manufactured from two different consistency levels of pulp slurry was examined by measurement of the fiber orientation in the paper thickness direction. The standard deviation of the probability density distribution function of the fiber orientation in the paperboard made from 3.3% (high consistency) pulp slurry was found to be higher than that from 0.9% (low consistency) slurry. This indicates that the paperboard from a high consistency pulp suspension has rather a felt-like structure. The felt-like sheet structure of the high consistency paperboard was proved to be attributable to the core layer structure. The standard deviation of the fuction in the cross machine direction in all of the paperboards tested was higher than that in the machine direction. This implies the existence of microstriation in the papers which was probably introduced during the drying process.

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Wool fabrics were treated with O₂, Ar, CH₄, CHF₃, and CF₄ low temperature plasmas. The effects of the treatments on the dimensional stabilities of the fabrics were investigated on the basis of dimensional change at various moisture regain and felt shrinkage after repeated home laundering. In order to soften the harsh handling of wool fabrics caused by low temperature plasma treatment, the fabrics were treated with several kind of softners. Low hygral expansion and low felt shrinkage were achieved without deterioration of soft handling by the plasma treatment and the subsequent reactive silicone elastmer treatment.

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The strengh of two needle lockstitch seams was studied using the theory of the minimum loop strength of thread. In general, the strength of two needle seams F₂ is expressed as follows: where θ is a variable which lays between 0 and 1 and is considered to be influenced by sewing factors such as thread combination, thread properties and consumption. Both F₁ and F₁′ are the theoretical strength, and F₁ is the strength of a stitched line broken faster than another one in testing. In case of θ=1, two stitched lines in the seam will be broken at the same time and the seam will show the maximum strength in its combination of threads. F₁ (and F₁′) could be given by the following formula: where N is the number of loops in a stitched line, μ and σ, mean value and standard deviation of loop strength of thread respectively, and k, the correction term which mainly reflects the influence of loop angle at the interlacing part of the stitch. E(R_m) is the expected value of R_m which is defined as follows: where x_m is the minimum loop strength. E(R_m) is calculated from the following equation: where Φ is the standard normal distribution function. In this study, k was assumed to be constant under our experimental condition and was given by the average value of k calculated from a case of single needle seams. θ was equated as the linear form using Δl which means the difference of the thread lengths per stitch between two stitched lines at the both breaking points. It was shown that the predicted strength of two needle seams agreed well with the experimental values.

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