Elastic moduli of crystalline regions of poly (ether ether ketone)_??_(PEEK) in the direction parallel (E_l) and perpendicular (E_t) to the chain axis were determined by X-ray diffraction. The observed moduli E_t are as follows; (110); E_t=5.9 GPa, (200); E_t=4.2 GPa, (020); E_t=5.0 GPa. The E_t value for the (200) plane is nearly equal to that of polyethylene (ca. 4 GPa). This means that there is no especially strong interaction other than dispersion forces in this direction. But E_t values for the (020), (110) planes are somewhat large. This is considered to be due to the dipole-dipole interactions between ether (carbonyl) linkages, since these functional groups are superposed upon each other in these directions. On the other hand, different orders of meridional reflections give different E_l values (31, 57, 71 GPa for (002), (006) and (008) plane, respectively). This phenomena may be due to the increase of the crystallite size by the applied stress. Judging from the similarity to the calculated E_l value (69 GPa), it seems that the E_l value for the (008) plane (71 GPa) is valid, from which the force required to stretch a molecule by 1% can be calculated as 1.64×10^-5 dyne.

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Investigations have been made on the fine structure and the physical properties of the blend film composed of silk sericin of Bombyx mori and poly (vinyl alcohol). The microphase separated structure was found in the blend film. The interfacial region between two phases may consist of PVA-sericin complex. The complex formation seems to yield the increase of fracture strain and the decrease of elongation at high temperature.

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Variously deacetylated chitin (DAC) fibers were prepared by several coagulant systems, such as CuSO₄-NH₄OH, alcoholic sodium hydroxide and CuSO₄-H₂SO₄. These fibers were found to have similar tensile properties independent of the spinning conditions. But the higher degree of protein immobilization was observed for DAC fiber prepared from CuSO₄-NH₄OH coagulant than those by other systems. The tensile properties of DAC fibers, especially wet properties and knot strength, were improved remarkably comparing with those of chitin and alkyl-chitin fibers.

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The sorption behavior of disperse dyes, 4-hydroxyazobenzene and 1, 4-diaminoanthraquinone, on the unextended and extended wool fibers was compared with that of acid dyes and the results were discussed in connection with the structural change of wool fiber.
Linear sorption isotherms were obtained for the disperse dyes independent of the extent of extension of wool fibers, and the equilibrium dye uptake increased with increasing the extension ratio. The heat of sorption for each dye was constant irrespective of the structural modification not only of the cuticle layer but also of the interior of wool fiber. It was found that the increase of the equilibrium dye uptake with increasing the extension ratio is due not to the change of the keratin-dye interaction mode but to the increase of the effective volume for dye sorption by stretching. The sorption rate of disperse dye showed a straight line passing through the origin both for the unextended and extended wool fibers, indicating that there is no surface barrier effect for the disperse dye and that the structural modification of the cuticle layer and the interior of wool fibers little affects the sorption rate of disperse dye. These results are different from those on acid dyes reported previously.

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This paper deals with the durable-press finishing for cotton fabrics using dimethylol ethyleneurea (DMEU) condensates having various chain lengths. The results obtained at various concentrations of the crosslinking agents showed that such agents with shorter chain lengths improved dry crease recovery angle whereas wet crease recovery angle was not affected by chain length.
A better balance between the dry and wet crease recovery angles was obtained by increasing crosslinking agent content and also by using the crosslinking agents with the shorter chain length.
The increase of dry and wet crease resistance caused a decrease in the tensile strength of finished fabrics. A small decrease in tensile strength was observed when crosslinking agents with longer chain length were used. The effects of the chain length of crosslinking agents on the physical properties of durable-press cotton fabrics may be explained as the crosslinking structure formed in the finished cotton fabrics.

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The crosslinking structure and physical properties of cotton fabrics treated with dimethylol ethyleneurea (DMEU) condensates having different chain lengths were investigated.
It was found that the reaction of the reagent changed at 4% of the concentration. A crosslinking reaction between the reagent and cellulose was the main reaction below 4%, whereas the condensation reaction between the reagents occurred predominantly at the concentration above 4%.
The dry crease recovery angle was related to the product of the number of crosslinks and the square root of crosslinking length. The wet crease recovery angle was related to the product of the crosslinking length and the number of crosslinks.
Accordingly, when the crosslinking length was shorter, the dry crease recovery angle became larger and the balance between dry and wet crease recovery was improved.
It was also found that the tensile strength was directly related to the number of crosslinks: fewer crosslinks and longer crosslinking length increased the retention of tensile strength when nitrogen content of treated fabrics was the same.

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Fourier transform infrared transmission spectroscopy without destructive sample preparation was applied as a convenient method for evaluating the silane coupling treatment on E-glass cloth that is usually employed to make laminate boards. The glass cloth treated with a silane coupling agent, γ-anilinopropyltrimethoxysilane, was subjected to the measurement in the intact state. To eliminate the absorption and the scattering by the glass cloth from the spectra measured with the treated glass cloth, the difference spectra were obtained with the original cloth as a reference. Those spectra gave the same absorption bands as those of the coupling agent alone above 1200cm^-1 The siloxane band was affected by the erosion of glass surface with acetic acid which was employed in silane treatment. When the cloth treated with acetic acid solution free from agents was used as another reference, the difference spectra gave no peaks due to siloxane formed on glass surface. This disappearance means that the siloxane bonds are not detectable in this method. In addition, the absorption bands due to the coupling agent treated on the glass were little given below 1200cm^-1 These results are attributed to the anomalous dispersion near the intensive absorption due to the glass.

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Factors affecting the surface shape of a hard-twist-yarn fabric were experimentally examined in terms of the weaving and heat-set conditions, and particularly the crystallinity of the original fibers. The results obtained are as follows:
(1) The number of ribs increases in proportion to the torque which remains after the twist set was given to the yarns; the increasing rate is high (or low) at the set temperature higher (or lower) than the annealing temperature of the original yarns.
(2) The height of ribs depends on the torque and shrinking force generated in the yarns when the fabrics are scoured.
(3) The higher the crystallinity of the fibers, the larger the yarn torque is. This gives rise to a large number of thinner ribs.
(4) The number of ribs increases and the rib height decreases with increasing twisting tension of the yarn. The rib height also increases with increasing twist-set tension applied to yarns.

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Poly (ethylene terephthalate) (PET) fiber and fabric were treated with a continuous high pressure steaming machine. The degrees of fixations of C. I. Disperse Violet 1 and Yellow 7 for the fabrics treated with high pressure steam, superheated steam, and dry heat were compared. Also the morphological changes of the fibers caused by the high pressure steaming were investigated by measurements of X-ray diffraction pattern, crystallite size, density, and saturation dye-uptake value in comparison with those induced by the superheated steaming and the dry heat treatment. The degree of fixation was found to increase in the following order: dry heat treatment, superheated steaming, high pressure steaming. Furthermore, the high pressure steaming enhanced the crystallinity and crystallite size more largely than the dry heat treatment or the superheated steaming, whereas the saturation dye-uptake value was unchanged by these steaming and heat treatment.

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