The tensile strength (σ_b) and the ultimate elongation (ε_b) of an acrylonitrile-methylacrylate copolymeric fiber were measured at various temperatures under conditions of constant stress and constant strain rate. Results obtained may be summarized as follows:
(1) In the creep rupture experiment, the curves of σ_b against the time to break (t_b) at various temperatures on double logarithmic scale are superposed by shifting them along the logt_b axis without any temperature correction of σ_b, the shift distance required to effect the superposition being loga_T. On the other hand, the curves logε_b against log t_b are superposed by shifting them along the logt_b axis and by shifting them along the logε_b axis, the shift distances required there being loga_T along the logt_b axis and logb_T along the logε_b axis. In the similar manner the composite curve of compliance at break against t_b, and a composite “failure envelope” plotting against ε_b/b_T are constructed.
(2) The tensile strength, which depends on a. local structure of the fiber, may hardly be affected by secondary structural changes of the fiber with temperature, so that the composite curve of ε_b against t_b, may be obtained without any temperature correction. The ultimate elongation, which may be correlated to sum of strains of the structural elements of fiber, may be affected by secondary structural changes of the fiber with temperature, so that the shifting along the logε_b axis is required in the superposition procedure to get the composite curve of ε_b against t_b.
(3) General behaviour of the composite curve of the compliance at break is similar to the one of the creep compliance for amorphous polymers, where the creep compliance shows the transition from the glassy to the rubbery state.
(4) In the constant strain rate experiment, the composite curve of ε_b, against t_b and the composite “failure envelope” are obtained, using the same values of the shift factors, a_T and b_T.
(5) Relation between the ultimate properties and the reduced time to break depends on the test methods, but the composite “failure envelope” is independent of the test methods.

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The graftfng of styrene onto dyed nylon 6 fabric by persulfate initiator has been studied. The experimental procedure and the results are as follows:
nylon 6 fabrics dyed with various acid dyes were treated with dilute Ammonium persulphate solution for 15 minutes at 50°C, and washed with water, dried at room temperature. Graft Copol-ymerization was carried out in vapour of water and styrene at 94°C. The homopolymer was extracted with benzol-ethanol mixtures.
The grafting was affected by the concentration and molecular structure of dyes. Although the degree of grafting of nylon 6 fabrics dyed with acid dyes was lower than that of undyed one, fabrics with light and medium shade were grafted with styrene smoothly without much fading and change of tensile strength. Almost no grafting was observed when fabrics were dyed with dyestuffs including quinone or aromatic nitro group in their molecule. The Measurement of the inhibitory power of acid dyes and hydroquinone were carried out by dilatometory: the inhibitory power of acid dyes was much lower than that of ordinary polymerization inhibitor (hydroquinone).

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The Rf-values for 15 acid azodyes were determined by paperchromatographical method using different developers, and it was found that if water was used as the developer, a close relation exists between the Rf-value and the affinity of the dye ion for Amilan.
From the determination of the Rf-value, in which the developers mixed with butanol, ethanol and water in the various ratios were used, it was found that the Rf-value varies with “inorganic property/organic property-value” of the dye and the developer, and showed a maximum where the values for both are nearly equal.
The relationship between the Rf-value obtained using water as developer and the affinity is discussed, and it is concluded that there is an intimate relation between them, provided that van der waals forces played an important role in the affinity of acid dyes for polyamide fiber. Furthermore, it is easy to obtain qualitatively the dyeing property of unknown acid azodyes for polyamide fiber by determining the Rf-value by the paperchromatography.

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Some aromatic compounds containing hydroxyl group in the ortho position to the nitroso group are isomerised to quinone oxime, which combines with metallic salt to produce coloured complex. Metal-complex possess property of very sparingly soluble in water. Showing part only of the benzene ring adjacent to a nitroso group, and its mechanism is two folds-
The typical process of its application is as follows: First, wetted loose wool are soaked at 50°C. in a bath containing 10_??_15% acetic acid and 8_??_15% naphthol sulfonic acid, the temperature of the bath is raised to boil in 30min. and kept at boiling for 1hr. Next, after the bath in drained, it is cooled slowly down to near 0°C., 3% sodium nitrite is added, cooling continued for 30_??_60min. And then after the wool is sufficiently rinsed, the colour is developed by chelation for 30min. at 100°C. in fresh bath containing 3_??_5% metallic salt and 10% acetic acid. Most compounds can produce complex by introducing nitroso group into the same bath, but in this case the necessary requirment is that it must be absorbed by the wool completly in the bath.
Amino naphthol, being cheaply available, are largely employed as intermediate of azo dyestuff for practical use, and a large range of shades are obtained from different metal, e. g. Al, Cr, Fe, ……, by taking advantage of the polygenetic character. In general, ferrous sal t gives the brightest hue and best fastness to rubbing. To dye the wool with Naphthol Green only a small quantity of nitroso dye is used, but nitrosocompounds also may be employed by making good use of its property capable of producing metal-complex.

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Dependencies of types of fibers and structures of the fiber assemblies on the transport mechanisms of water have been under investigation. In this paper, the comparative measurements were made on the process of horizontal transport of distilled water in the various assemblies which were made from several kinds of fibers and the results obtained are discussed.
Preparation of experimental materials is described in the previous paper. The required quantity of sample fiber was uniformly stuffed into an Acrilan tube of 0.9cm in diameter and 10cm in length, thus the column of fiber assembly was made. The degrees of porosity (degrees of opening) of the assemblies were 65, 75, 85 and 90% respectively. The Acrilan tube was kept horizontally and the end of the tube was brought to contact with distilled water. The rate of water transport through the assembly was measured by eye-observation and an electrical contacting device. The travel of water front as a function of time has been followed for each kind of fiber and degree of porosity.
The water transport curve varies greatly with the kind of fiber in the case of same degree of porosity. The assemblies of acrylics which belong to synthetic fiber were penetrated extremely rapidly at all ranges of porosity examined. It was described in the previous paper that in the vertical capillary penetration of water through the assemblies of acrylics, acetate, vinylon, absorbent cotton and rayon the increase in openness (porosity) of the assemblies give rise to the decrease in the penetrating quantity. In contrast to this, the rate of horizontal water transport has a linear relationship with the porosity, and, in general, the greater the diameter of capillaries the larger the rate of wicking. In the compact rayon assemblies of small porosity, the wicking rate was greatly reduced owing to the possible clogging of capillary spaces by the swelling of fibers. The square of the travelled distance (S_h) of water front was plotted against time (T_h) for each degree of porosity of rayon assembly. From the linearity of this relationship equation, S_h²=K^c•T_h was obtained in the wide variety of porosity of assemblies made from sufficiently wettable fibers.

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