The mechanisms of plastic deformation in strip biaxially stretched syndiotactic 1, 2-polybutadiene film (st-1, 2-PB) have been explored by means of wide angle X-Ray pole figures. In strip biaxial stretching, reciprocal lattice vectors of (010) and (200) were found to orient preferentially in film normal (thickness) and transverse directions. Changes in distribution of each reciprocal lattice vector orientation with drawing of sample films are calculated by applying a previously reported method based on a modified affine deformation. These calculated results were compared with those of X-Ray diffraction measurements. Finally preferred orientations in the samples due to actual movements of the crystallographic plane were discussed.

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In thermal conductivity measurements determined using a probe, there have been no papers that have examined the effects of the probe diameter on the thermal conductivity of molten polymers. The purpose of this study is to investigate the performance of probes with different diameters in order to clarify this effect, to discuss the temperature dependence and accuracy of thermal conductivity measurements, and to determine the optimum relationship between sample diameter D and probe diameter d. The thermal conductivity of a number of polymers is estimated for a probe diameter that approaches 1 mm at 50, 100 and 200°C. From these results the following conclusions are drawn: The temperature dependence of the thermal conductivity of polypropylene (PP) and polystyrene (PS) increases with increasing temperature. The thermal conductivites of molten PP and PS are observed to be constant or to gently increase with increasing temperature, although they exhibit a dip at the melting and glass transition points. In addition, the thermal conductivity of molten polymer is found to decrease with decreasing probe diameter, and measurement accuracy can be improved from ±12.2% to ±7.3%. The estimated thermal conductivity of PP and PS in the case when a probe diameter of was used 1 mm are 0.12 W/m·°C and 0.10 W/m·°C, respectively. The optimal specimen diameter D for a given probe diameter d is D>9d.

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A novel method to measure the topological features of three-dimensional (3D) network structures is presented. It involves skeletonizing 3D structures using a new axis thinning (“skeletonization”) algorithm. The 3D structureswere imaged by laser scanning confocal microscopy (LSCM), and by transmission electron microscopy (TEM) assisted by computer tomography (CT). Unlike the existing 3D skeletonization techniques, the proposed method provides the rules for skeletonizing at the edge planes of the volume data. The algorithm assures the positions of the junctions. They are useful in the evaluation of the topological quantities of the network, which were neglected in the existing 3D skeletonization algorithms. The 3D skeletonization was thoroughly tested using a model network structure, Gyroid, which is one of the infinite periodic minimal surfaces (IPMS). We confirmed that the method was robust and gave an accurate number of junctions.

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Films of 6-dibutylamino-1, 3, 5-triazine-2, 4-dithiol (DB) were formed on a metal substrate by the conventional vacuum deposition method. Molecular structures of adsorbed DB were investigated using XPS to examine the influence of substrates on adsorbed gases, and the thickness of oxidized films. The metal substrates were baked under an ultra high vacuum condition to remove adsorbed gases, oxidized under an ambient atmosphere to give oxidized films, and subjected to deposition of metal to prepare a clean substrate. The results showed that DB easily formed disulfide bonds and mercaptide bonds to gases adsorbed on the substrate. The chemical reactions of the substrate occurred with an increase in OH group and adsorped H₂O, and the reactions were independent of the thickness of oxidized film. As for the depositing metal, C, N, and S of DB were shown to be bound to the surface by XPS. It is assumed that the adsorption on the surface occurred through the triazine ring.

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In the deterioration of oriental lacquer, four factors, i. e., humidity, temperature, atmosphere, and light, are considered important, and the effect of atmosphere was examined in this study. Oriental lacquer films were irradiated with a fluorescent lamp for museum in the atmosphere of oxygen, nitrogen, or air. The change in gloss and color of the films was suppressed at most in oxygen. Surface analysis indicated an increase in carboxyl groups under the oxygen atmosphere. It was found that the oxidation polymerization of the urushiol developed very fast in oxygen to suppress the change in the appearance.

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The changes of the dynamic viscoelasticity during the fatigue process and the fracture surface phases were investigated to explain the effects of the stress amplitude and environment temperature on the fatigue fracture mechanism of polycarbonate (PC) in this study. The results are as follows: (1) PC is a typical ductile material because PC has a high heat transformation temperature. (2) For the fatigue life change at each testing temperature, the fatigue life on the levels of low and high stress would decrease with the increase in the stress amplitude ; however, the reverse phenomenon would appear on the level of the middle stress. But this trend would be slight. The increase in the fatigue life is related to the partial ductile fracture during the crack propagation process and the rise in the molecule orientation due to the specimen extension. (3) The fatigue life would decrease with the increase in testing temperature. The degree of decrease on the high stress level was more than that on the low stress level. (4) The fatigue fracture mechanism is concerned with the E' value in the fatigue process and the change of tan σ on each stress amplitude at each testing temperature. (5) The fatigue fracture mechanism at high temperature is similar to that at room temperature.

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For obtaining paint films with high conductivity of paint films even for decreasing conductive filler content, the coatings consisting of nickel flake powders, methylethylketone, and polystyrene have been investigated using magnets. The critical nickel content which gave the highest conductivity in dry paint film was changed under magnetic treatment, but the volume resistivity of paint films treated magnetically was lower than that for untreated film at each nickel content. The magnetic treatment provided high conductivity to dry paint films even at a low magnetic force (200G). The volume resistivity of paint films increased with a magnetic force in the range of 200G to 3800G, which is given to the coating film. The magnetic treatment was also effective for expanding the available range for the amount of solvents as well as for increasing the conductivity of paint films. The conductivity of paint films treated magnetically did not depend upon distance between terminals in the measurement of conductivity. The increase of conductivity of paint films by magnetic treatment is explained by the shortening of contact distance between filler particles, which occurs thanks to the magnetic force.

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It has been almost impossible to make experimentally composite materials with randomly oriented fillers of a heavy density in matrix resins of low viscosity, because the fillers precipitate out at the bottom of the mold due to gravitation before the liquid resins have time to cure with chemical reactions. In this paper, a new bi-axial rotational molding apparatus to cure the resins containing heavy fillers has been developed and the distribution of short glass fibers and their nickel-coated fibers has been investigated (using this instrument). An aminimide compound, adopted as a latent hardener for epoxy resins, was thermolyzed to generate a tertiary amine for catalysts and an isocyanate at 130°C and above. The results obtained from SEM cross-section photographs and from fiber orientation measurements with a rotative polarization system of millimeter waves showed a random orientation of fibers. The moduli of the composites measured by flexural tests were very close to the values calculated from Nielsen's theoretical equation for random orientation in orthogonal directions.

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The dynamic storage modulus was investigated for some close-celled polyethylene foams by dynamic viscoelastic measurements in compression mode. The dynamic modulus has been found to correlate with the compression hardness positively, and the difference between the static modulus and the dynamic storage modulus is small. In the compression modulus of close-celled foams, E/E₀= (1-V_f) ² was determined by the absence of resistance against the pressure inside the cells in the experimental equation given by Mihira et al. Their value was found to be in reasonable agreement with the experimental data of the dynamic compression modulus. The resistance against the pressure inside the cells has no effect on the static modulus or the dynamic storage modulus.

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