Polyether-ether-ketone (PEEK) fibers were prepared at a range of take-up speed from 9.9 to 920m/min, and the effects of take-up speed, drawing (draw ratio=x1-x4) and heat treatment (200-325°C) on structure and properties were investigated. The molecular, crystalline and amorphous orientations, crystallinity and crystallite size were determined from the measurements of WAXS, SAXS, density and birefringence. In a range of take-up speed up to 110m/min, the molecular orientation of as-spun fibers increased with increasing take-up speed, and then showed a tendency to level-off. The birefringence of the amorphous region of as-spun fibers was more than ten times larger as the crystalline region. This suggests that the crystallization proceeds mainly in a highly oriented structural region in fibers on the spin line. The crystallite size of as-spun fibers was comparable to that of heat-treated fibers. The crystallite size was the largest in the direction of the normal of the (110) plane for all the fibers prepared, irrespectively of take-up speed, drawing and heat treatment. With the fibers heat-treated after drawing, the amorphous orientation showed a maximum at a heat-treatment temperature of about 250°C. On the other hand, with the fibers heat-treated at a fixed length it increased monotonically by heat treatments up to 325°C. For analysing the mechanical properties measured for PEEK fibers prepared under various conditions, the theoretical modulus of an extended PEEK molecule was calculated, and as the moduli of the crystalline and amorphous regions, values of 69 and 63 GPa were obtained, respectively. It has been found that the initial moduli of the PEEK fibers of various crystallinities can be related to the orientations of amorphous region. By applying a two-phase model combining the crystalline and amorphous regions in series, it has been obtained for various PEEK fibers that the initial compliance of the amorphous region can be represented as a linear function of the amorphous orientation.
The glass-transition, cold crystallization and melting behaviors were also measured by DSC, and their relation to fiber preparation conditions were studied. The heat of fusion, which was calculated for the PEEK crystal from the DSC measurement, was about 130kJ/kg.

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A mathematical model is developed to predict the transverse elastic moduli of unidirectional fiber composites. Two cases are investigated for fiber/matrix interfacial bondings: perfect bonding and complete debonding. The elastic property of a fiber is assumed to be transversely isotropic. Elastic interaction among fibers is considered there. In the case of complete debonding, the cavity formation model is adopted and the fiber and the cavity around it are replaced by an anisotropic imaginary inclusion. Effective elastic moduli are obtained for the transverse tensile and compressive modes, and for the transverse and longitudinal shear ones. The limiting case in which the matrix contains fiber-shaped voids in place of fibers is also touched upon. Numerical case studies are presented for two metal matrix composites, where the effect of interfacial bonding state on the transverse properties is mainly discussed.

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The fatigue behavior of Poly (ethylene terephthalate) (PET) tire cords were investigated as functions of degree of polymerization and twist number of tire cords both of which were the major factors governing the fatigue properties.
The fatigue tests were conducted by means of a Goodyear tube and a Goodrich disk fatigue testers. After the fatigue tests, tire cords isolated from rubber were examined by an optical microscope in a view point of fractography.
The results are summarized as follows:
(1) The higher the degree of polymerization of PET tire cord, the greater the resistance to compression-induced fatigue.
(2) In the tube fatigue test, the fatigue life considerably depends on the temperature of tube. The tube temperature was found to be affected by the degree of polymerization of PET tire cord.
(3) In the case of disk fatigue test, a fibrillation was observed at the very early stage of fatigue test.
(4) The structural deterioration such as occurrence of kinkband was observed only in the cases of low degrees of polymerization or low twist number which are considered as giving the cords a very severe fatigue condition.

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The optimum reaction conditions in solid-state polycondensation of poly (1, 4-butylene terephthalate) (PBT) were investigated in order to obtain high molecular weight PBT. It was found that the solid-state polycondensation of PBT proceeds at a temperature in the range of 185 to 200°C under reduced pressure. This is due to the fact that the activation energy of the polycondensation reaction is 29.5kcal/mol and considerably smaller than that of the thermal decomposition reaction of PBT, i.e., ca. 40kcal/mol. To accelerate the reaction rate, it is important to carry out the polycondensation reaction at low humidity using PBT having a low carboxyl end group content and a large specific surface area.

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A semilogarithmic dependence of the effect of the anthraquinone (AQ) addition level within 0.05-1.0% on the weight of spruce and pinewood chips mixture (75:25) has been verified in soda process. The following resulting pulp characteristics are involved: Kappa number, Kappa number reduction, lignin content, lignin content reduction, carbohydrate content, and viscosity. The quality characteristics of soda-AQ-based pulps are affected vitally by the AQ addition level and alkali concentration. At an equal AQ charge a higher delignification selectivity will be obtained through the application of an increased active alkali charge (18% Na₂O on wood), this being expressed in the yield-to-lignin unit ratio in contrast to a lower active alkali charge (16% Na₂O on wood). At an identical delignification selectivity during soda pulping with the catalytic effect of AQ a higher degradation of carbohydrates will occur, expressed in the viscosity reduction, than during kraft delignification.
Mechanical properties expressed in the tear index to breaking length relationship of the soda-AQ based pulps delignified by 16% Na₂O active alkali with 0.3-1.0% AQ addition are identical with or even better than those present in kraft pulps. Pulps produced by delignification with 18% Na₂O active alkali and 0.3-1.0% AQ addition give mechanical properties similar to those of kraft pulp.

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This is a paper concerned with investigating how the consumers and specialists perceive value or chroma differences of color pile fabrics in various value or chroma conditions. And the relationships between sensory values evaluated by the sense of sight and the visual physical properties (hue, value and chroma) were examined by the use of multiple regression analysis.
The results are as follows.
(1) When consumers converted the visual physical properties (hue, value and chroma) into the sensory values, their change rate were high. But the change accuracies were not good. On the other hand, the specialists' change rates from the visual physical properties to the sensory values were low because of a long term training in the color recognition.
(2) As a result of multiple regression analysis, it was found that the common predictive variable of the four sensory values “softness”, “thickness”, “smoothness” and “lightness” evaluated by consumers and specialists was mainly value and that “fullness” was described by the multiple regression equation of hue and chroma.

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Dye solution (Orange II) from an infinite dyebath was passed through a semi-micro textile assembly (silk fibroin, 10-30mg) placed in a glass column (3mm diameter) at constant temperature. The change in the dye consentration after passing through the assembly was measured continuously by means of photometry. The data obtained from such measurement allows to draw the curve of dyeing rate from the infinite bath.
The value of the apparent diffusion coefficient of dye in the fiber (D_w) and the equilibrium uptake of the dye (M_∞) were estimated from the curve of dyeing rate by means of non-linear least squares method. The value of D_w was increased as the amount of the specimen placed in the tube (W) was decreased, but the value of M_∞ was almost constant regardless of W. The value of D_w extrapolated to W→O may be regarded as the true diffusion coefficient (D_o). The value of activation energy of diffusion calculated using D_o or various D_w was almost constant.

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