In order to examine the structure of interlamellar tie fibrils found by Keith et al. (J. Polymer Sci., A-2, 4, 267 (1966)), the mixtures of polyethylene and paraffine were crystallized at various temperatures from melt into thin films on various substrates, and the resultant textures were studied by an electron microscope before and after paraffine was extracted by xylene. When a micro cover glass was used as the substrate, sheaf-like crystals in the order of 3μ were observed, suggesting that the substrate facillitated the nucleation in the thin film. When carbon and mica sheets were used as the substrate, the ordinary two dimensional spherulites with macro fibrils grown radially and the so-called banded spherulites were observed in the thicker region of the film. In the very thin region of the film were observed ribbon like crystals, which have not been found so far. They are fibrilar but can be considered as monolayer lamellae laid on the substrate. The lack of twisting of the lamellae suggests again some effects of the substrate. Under the same conditions as those used by Keith et al., the open structure of the spherulite they found was not observed. When polethylene/C₃₂H₆₆ ratio was 1:2 and the mixture was crystallized under higher supercoolings, the open texture similar to the Keith's was observed. However, the interlamellar fibrils was not observable but the fibril like materials seen among the lamellae were in fact composed of small irregular shaped lamellae. In view of the pronounced effect of the substrate on the morphology of the resultant spherulites, it seems rather questionable that the interlamellar fibrils found by Keith et al. are formed in bulk crystalline polymers.

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Effects of drawing on the α-β transition and the formation of voids in Tussah silk fibroin were studied by means of X-ray diffraction at wide and small angles, polarizing microscopy, and electron microscopy.
1) It is found that the fibroin coagulated in silk gland has a morphology of small spherulitic particles (ca. 240A in radius) in which hydrophobic residues in the polypeptide are arranged in the inner part and the hydrophilic residues in the outer part. This structure is destroyed by the drawing of gel. The α-helix form of the molecule changes gradually into the extended β-form as the draw ratio increases: the β-component becomes predominant at the draw ratio higher than 6-8times. However a small amount of αa-conformation still remains even at the highest draw ration 14. The crystallinityof the specimen (36% at the beginning) decreases at first but turns to increase, having a minimum at the draw ratio of 8. On the other hand, the birefringence increases slowly but monotonously as the draw ratio.
2) The mechanism of the void formation as well as the effects of drawing on their shapes was examined through use of microscopies and a small-angle X-ray method. It is considered that the formation of voids is caused by the emission of water which have been occluded in the gel. Such voids become smaller and longer by drawing the gel and align in the direction of the fiber axis, the ratio of the length to the width of the voids attaining two.

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Graft copolymerization of acrylamide onto the ⁶⁰Co γ-ray pre-irradiated cotton fabrics was investigated in various water-dioxane mixtures. The effects of the grafting mediums on the swelling behavior of the fabrics, degree of grafting or dimensional stability of the grafted fabrics (after extracted with hot water) was also studied.
The degree of swelling of the cotton fabric in aqueous dioxane and 15% acrylamide aqueous dioxane solution where water contents are 20_??_80% shows higher values than those in water or dioxane alone.
Absorbed monomer content in the cotton fabrics from the monomer solutions is almost constant and independent of the composition of the mediums and the degree of swelling of the fabrics.
Degree of grafting or rate of graft copolymerization is nearly constant up to 50% dioxane content in the grafting mediums and then a significant decrease is observed, while the rate of catalysed solution polymerization of acrylamide gradually decreases with increasing dioxane content in the polymerization mediums with the exception of the medium containing 10_??_30% water content.
Cotton fabrics which were grafted in relatively higher swelling media show less dimensional stability during grafting and hot water extraction, and the conditioned (dry) tensile strength of warp of the fabrics appears to be slightly higher than those obtained in less swelling media.

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The present investigation was undertaken to shed light on the effects of the composition of hard and soft component, block length and distribution of sequence length of elastic condensation block copolymer upon fiber properties.
The polymer used for this purpose was polyether-polyester block copolymer composed of B type polyester (polyethylene-1, 2-diphenoxyethane-p, p′-dicarboxylate) as hard segment and PEG (polyethyleneglycol) as soft segment.
The results are summarized as follows:
(1). The effect of composition; The values of tensile strength, Young's modulus and work for extention of melt spun fiber became larger with the increase of B type polyester content, whereas elongation and tensile recovery became lower. When 4000 molecular weight PEG was used, these properties showed minimum or maximum value at the composition of 50:50 (wt).
(2). The effect of block sequence length; As the glycol molecular weight was increased, fiber properties varied with a trend toward greater tensile strength, Young's modulus and work for extention, and toward lower elongation and elasticity. These result; could be explained on the basis of crystallinity of PEG block sequence and confirmed by X-ray diffraction diagrams which showed that the crystallinity of PEG segment was enhanced with increment of its component or lengthening of its sequence in block copolymer.
(3). The effect of distribution of block sequence length; Though two block copolymers having the same composition and the same block sequence length (one of which was prepared by the method of “two step polycondensation” and the other by “one step polycondensation” had nearly the same intrinsic viscosity numbers, peak widths of heat of fusion of crystalline region in DTA melting thermograms were sharper in the former and especially in the solution properties, Huggin's constants were widely dissimilar from each other.
“Two step polycondensation” mentioned above refered to the following polycondensation procedure, that was, block copolymer was prepared by polycondensing polyester oligomer having both terminal OH groups with certain molecular weight polyether derivatives having both terminal ester groups. “One step polycondensation” block copolymer was prepared by copolymerizing polyether having both terminal OH groups with ethyleneglycol and dimethyl carboxylate.
It was reasonable to estimate that the properties of these two polymers suggested the difference of distributions of sequence length in these polymers, and then the mechanical properties of the melt-spun fibers of these polymers were compared with each other.
It was manifested that no marked differences were observed in tensile strength and elongation between “one step” method copolymer and “two step” one, while higher Young's modulus and larger work for extention were obtained for “two step” procedure.

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A method for determing the degree of swelling was derived, since the centrifugal method gives no accurate results.
A clear transition point was found on a stress-strain curve of fabrics during drying process. This transition point can be observed only when the fabric is uniformly wet and the water evaporates slowly from the fabric. A correlation between the dyeability and swelling degree was found in the pad dyeing of Nylon-6 fabrics.

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Polarographic half-wave potentials E1/2 of some disperse azo dyes were measured in dioxane Britton-Robinson's buffer solution (3: 7) at pH 5.0. The relation between the chemical structure and the E1/2 were studied.
1. [E1/2] of the disperse azo dyes and their model compounds were measured by extrapolating their concentration to zero.
2. [E1/2] attributed to the nitro groups of azo dyes were -0.553_??_-0.705 volt.
Nucleophilic groups increased (-[E1/2]) while electrophilic groups decreased it.
(-[E1/2]) of dyes of this type were considerably lower than that of monosubstituted nitrobenzene.
3. [E1/2] attributed to the azo groups of azo dyes without nitro groups were -0.444_??_-0.999 volt and lower than that of azo benzene (-0.404).
This is because the dyes have some nucleohilic groups.
(-[E1/2]) of 4′-×-4 amino (or oxi) azo benzene were plotted for Hammett's σ. The inclination of the line was minus.
4. It seems resonable to assume that [E1/2] of the disperse azo dyes with nitro group has a relation to the high affinity of dyes _??_or ester graup in fibers.

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