A stress plate modulator (SPM) is a waveplate, whose retardation varies sinusoidally with time depending on the supplied AC voltage. After describing how to construct the SPM and its oscillator circuit, an explanation has been given for the calibration and operation of the SPM in connection with the application to birefringence measurements of transparent films. The optical system consists of a He-Ne laser, a polarizer, the SPM, a sample, an analyzer and a photomultiplier tube (PMT). As pointed out by several investigators, such a system can allow us to determine a few tens of microradians in retardation by observing the AC component with a lock-in amplifier. The significant utilization of the DC component of the PMT output has been insisted. As performance illustrations, we have obtained the retardation of commercial cellophane films as a function of plies, demonstrating how to determine without using a standard quarter-wave or half-wave plate.

View full abstract

The measurement of elongational viscosity of polybutene-1 melt has been carried out at a constant strain rate with an elongational rheometer which measures simultaneously the diameter of elongating samples. Non-linearity parameter of the viscosity was calculated from the total elongational viscosity values by dividing with the values of linear parts. The non-linearity parameters of the elongational viscosity were almost independent of strain rate and temperature. Four rheological constitutive models of integral type were chosen and applied for the elongational flow at a constant strain rate. The chosen models were the Lodge model, the Bogue and White model, the Bernstein, Kearsley and Zapas model, and the Wagner model. These models predicted the non-linearity of the elongational viscosity at high strain rate well. However, the non-linearity parameter predicted from these constitutive models showed strong dependences on both strain rate and temperature.

View full abstract

Conformation of high-glycine (HG) proteins, a non-helical protein group derived from reduced and S-carboxymethylated wool keratin, has been investigated by circular dichroism and x-ray diffraction measurements on their cast films. It was found that these proteins are able to form a β-structure in the films cast from formic acid solution, as had been in the case of the high-sulfur (high-S) proteins which are considered to originate from the matrix between the microfibrils. The results were compared with those on the high-S proteins and discussed in terms of the known primary structure of a component protein from HG protein group.

View full abstract

Diffusion of dyestuff in “random oriented” and “oriented” poly (γ-methyl L-glutamate) (PMLG) membranes was studied. In the former membrane, helical rods orient randomly in the palne parallel to the membrane surface. In “oriented” membrane prepared by applying the electric field to EDC solution of PMLG, helical rods orient parallel to both of the membrane surface and electric field. The diffusion of dyestuff observed as the concentration gradient in the membrane, was analysed referring to the gradient calculated on the assumption of concentration dependent diffusion coefficient. This dependence corresponds to the diffusion with Langmuir type adsorption of dyestuff. The coefficient obtained in the direction parallel to the helical rod is a few times larger than that in perpendicular direction. From the geometrical consideration of the diffusion model, it is suggested that the aperture between helical rods is smaller than that obtained by X-ray analysis. Using electropositive Methylene Blue and electronegative Alizarine Red S, the effect of electrostatic nature of dyestuff on the diffusion in slightly electronegative PMLG side chain region was examined. The results suggest that Alizarine Red S may diffuse through a narrow, low affinity region rapidly, Methylene Blue may diffuse slowly through a more broad, high affinity region. This difference is exaggerated when the direction of diffusion is parallel to the helical rod.

View full abstract

Polyamides and polyesters were prepared from halogenated terephthalic acid with various diamines or diols. The effects of halogen substitution on the synthesis and some properties of these polymers were examined systematically.
η_sp/C of the polymers decreases with the increase of the number of halogen substituents on the benzene ring. The crystallinity and the melting temperature decrease generally by halogen substitution. The glass transition temperature of the polyesters also decreases by halogen substitution. The flame-retardancy estimated by thermogravimetry and self-ignition test increases with increasing halogen content of the polymers. The solubility increases by halogen substitution.

View full abstract

Aminodeoxycellulose having an amino group (DS, 0.37) on C-2 position, a chitosan analogue, was synthesized by treating 6-O-tritylcellulose with dimethyl sulfoxide-acetic anhydride, followed by oximation with hydroxylamine hydrochloride, reduction with lithium aluminum hydride, and final detritylation with hydrochloric acid in methanol. 2-Amino-2-deoxy-D-glucose was found in the hydrolyzate of the aminated cellulose by gas chromatographic (GC) and thin-layer chromatographic (TLC) analyses.

View full abstract

It is possible to insert a real twist into continuous filament yarn through a false twist mechanism by godet spinning. The secret of this novel method is that not the twist inserted in monofilaments, but only the twist added to the filament bundle is recognized as a real twist. As the defects of this method, large accumulating ratio or overfeed and large loops projecting from the periphery of the yarn were pointed out. In this paper elimination of these defects were attempted by applying two methods of opening a multifilament yarn into monofilaments. Many factors which affected the operating efficiency and yarn properties were described. The yarn thus obtained was found to have much less snarling tendency compared to the conventionally twisted yarn. Properties of the fabric woven from the obtained yarn were similar to those from the spun yarn rather than to those from the texturized yarn.

View full abstract

Carboxymethylated cotton fabrics having the degree of carboxymethylation of 2.0-4.4 mole were ion-exchanged with metal cations by immersion into aqueous solutions of various metal salts. Resistance to heat, acid, rot, and flammability of these metal-cation-exchanged carboxymethylated cotton fabrics were examined.
Loss of tensile strength of warp yarns of the carboxymethylated cotton fabrics by heating in air at 150°C were reduced by Na, Mn, Ni, Ca cation exchanges, but heat deterioration was accelerated by Cr, Cu, Zn, Al cation replacements. The effect of cation exchange was slight in the treatment with 30% sulfuric acid at 40°C. In soil burial test the tensile strength losses were reduced by Cr, Fe, Ni, Cu, Al cation exchanges. In flammability test Al and Sb cation-exchanged fabrics showed decrease of glowing time and increase of charred area, but on the whole the flameproof effects were insufficient. For comparison, cation-exchanged fabrics of acrylic acid grafted cotton were tested and sufficient inflammability was shown with the increase of grafting percent.

View full abstract