Effects of molecular weight on the fracture formation of polystyrene have been studied in terms of the fracture surface morphology and the mechanical property. The fraction of mirror-like fracture surface increased with decreasing molecular weight. Samples for low-molecular weights were fractured as the mirror-like surface.
The craze width and the crack length were examined in relation to the molecular weight. The released energy per one crack propagation and the energy for crack formation per unit area were also estimated. It is concluded that high-molecular weight samples crack brittle at the maximum rate of fracture propagation (Vc). Low-molecular weight samples crack at the rate lower than Vc, giving rise to the mirror-like fracture surface.

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The physical properties and the crystal structure of ethylene-vinyl alcohol (EVA) copolymers (vinyl alcohol content, VA 18.3_??_40.0 mole %) were investigated by X-ray diffraction method and differential scanning calorimeter.
The following results were obtained;
1) The lattice parameter of EVA change gradually from that of polyethylene (PE) with increasing VA content, except 36.3mole% VA containing EVA.
2) The lattice parameter of EVA (VA 36.3mole%) is similar to that of EVA (VA 18.3mole%) and the thermal diagram of EVA (VA 36.3mole%) is also similar to that of EVA (VA 18.3mole%). From these results, it may be reasonable to conclude that VA content of crystalline region of EVA (VA 36.3mole%) is nearly equal to that of EVA (VA 18.3mole%) in which VA content of crystalline region is similar to that of amorphous region.
3) The thermal expansion coefficients of EVA crystal are larger than that of PE because of inner stress of crystalline region due to the VA segments.

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Silk and wool fibers were treated with propylene oxide (PO) or 1, 2-butylene oxide (BO) in the presence of aqueous neutral salt such as Na₂S₂O₃ and KSCN according to Shiozaki and Tanaka, and the gas chromatography (GC) of the hydrolysates of the treated silk and wool fibers was studied for the identification and quantitative analysis of the artifact amino acids produced by the treatments with PO and BO. The GC analysis was carried out by the linear temperature-programmed method on OV-17 and Dexsil 300 GC columns after the amino acids in the hydrolysate being converted to n-butyl esters of N-trifluoroacetyl (BTFA) derivatives by the method of Gehrke et al.
The peaks of O-2-hydroxypropyltyrosine (PO-TYR) and O-2-hydroxybutyltyrosine (BO-TYR) were observed in the chromatograms of the silk samples treated with PO and BO, respectively, and the peaks found in addition to the corresponding modified tyrosine in the chromatograms of the wool samples treated with PO and BO were considered to be those of N-2-hydroxypropyllysine (PO-LYS) and N-2-hydroxybutyllysine (BO-LYS) respectively. The hydrolysates of silk and wool fibers treated with PO and BO were studied also by the ionexchange liquid chromatography (LC) with an automatic amino acid analyzer under normal conditions. It was found that PO-TYR coeluted with phenylalanine and that no modified lysine peak was identified in the chromatograms of the wool samples.
The Kováts retention indices and ΔI values of the BTFA derivatives of the artifact amino acids and of serine and threonine were determined and their correlation with the structure of the amino acid was discussed. The ΔI. values of PO-TYR and BO-TYR were equal to each other and as high as that of phenylalanine.
The relative molar responses of the artifact amino acids on a hydrogen flame ionization detector were calculated from the sum of effective carbon numbers of the structural units and used to estimate the contents of the artifact amino acids in the hydrolysates of the PO- and BO-treated silk and wool fibers by GC. The amount of PO-TYR thus obtained was lower by 18% than that estimated by LC in which the ninhydrin color yield of PO-TYR was assumed to be equal to that of phenylalanine.

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In order to clarify the dyeing characteristic of silk fiber, the equilibrated adsorption of hydrochloric acid as a model of Acid-dye was studied. The saturated amount of adsorption and thermodynamic parameters such as standard affinity, heat and entropy of adsorption were calculated by Gilbert-Rideal-and Donnan-theories. The experiments were carried out at 7, 30 and 50°C.
The results obtained were as follows:
(1) The adsorption isotherm was similar to L-type classified by Giles et al.
(2) By reciprocal plotting of adsorption, the saturation value of hydrochloric acid adsorbed by silk was estimated as 19.6×10^-5eq/g. This value is a little larger than the amount of the total amino group calculated from component amino acid.
(3) The standard affinities (Δμ°) of hydrochloric acid at 7, 30 and 50°C were calculated -7.35, -7.80 and -8.04 kcal/mol, respectively, using Gilbert-Rideal's equation. These values are somewhat larger than those for wool.
(4) The data obtained in this experiment were not fully represented by either theory of Gilbert-Rideal and Donnan, but the former was somewhat better than the latter.
(5) The standard heat (ΔH°) of adsorption were calculated -2.88kcal/mol in the range 7 -50°C. The standard entropy (ΔS°) for silk have positive value, which was the same sign of those for wool and nylon.

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Investigation was made on the rate of dyeing equations in regard to the dyeing of polyester fibre with commerical disperse dyes from the finite dyebath, which is common for practical dyeing.
Each of the equations presented by Wilson, Crank, Vickerstaff and Cegarra and Puente is found to fail to represent the dyeing behaviour over a whole dyeing process in the system concerned
The present paper proposes a new equation, which is incorporated with the observed delay in time from the theoretical curves in the early stages of dyeing, on the basis of a fundamental equation of the exponential form.
where α is a constant, and was made clear to give a value of 0.8 in the system examined. It was confirmed that the proposed equation gives a good fit to the time/adsorption isotherms obtained experimentally, irrespective of the type of dyes, dyeing temperatures and dyeing concentrations.

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C. I. Reactive Blue 19 (mono-functional reactive dye of sulfatoethylsulfon type) exhibits the good fixation for silk in weak acidic, neutral and weak alkaline solutions. Maximum fixation was achieved to about 80% in the pH range 7-8.
The products of this reaction were analysed by automatic analysis of amino acids reacted with silk. Here, two methods-analysis of filtrate and precipitate after hydrolysis of dyed-and blank dyed-silks were used.
As the result it has become apparent that the following amino acids reacted with C. I. Reactive Blue 19:
At pH 4; histidine, arginine, isoleucine
At pH 7; lysine, histidine, arginine, aspartic acid, serine, glutamic acid, glycine, alanine, valine, isoleucine, leucine, tyrosine
At pH 10; lysine, histidine, arginine, aspartic acid, serine, glycine, alanine, valine, isoleucine, leucine, tyrosine.
Especially lysine and histidine were very important, for these amino acids occupied 75-78% (pH 7), 54-69% (pH 10) of all reacted amino acids.

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Polyester fabric heated in hot air was cooled by various methods and investigated the effect of cooling condition on the crease recovery angle of fabric and Young's modulus and elastic work recovery of fiber. Furthermore, the change of fine structure of polyester fiber was studied by density gradient tube and X-ray diffraction.
The following results were obtained:
1) Polyester fabrics heated at different temperature of hot air were cooled gradually or rapidly in water, air and ethylene glycol down to 100-0°C. Crease recovery angle is considerably affected by cooling method. i.e., the higher the cooling temperature, the greater the crease recovery angle. The best result is obtained by gradual cooling from 100°C. Especially, it is desirable to cool gradually in the vicinity of glass transition temperature of polyester fiber.
2) Young's modulus and elastic work recovery obtained by the stress-strain curve of the fiber increase with the rise of cooling temperature. These increased by gradual cooling, and decreased by rapid cooling.
3) Crystallinity is almost no change by cooling method. X-ray patterns and lattice spacing of (010), (110) and (100) plane are not changed by cooling method.

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