The sodium-naphthalene-tetrahydrofuran method and the sodium-liquid ammonia method have been used for the surface treatment of polytetrafluoroethylene. For various specimens treated by the two method adsorption isotherms of water vapour and weight loss were measured. It has been found that in the former method the reaction takes place only at the surface layers, but in the latter case the reaction proceeds into the interior of the polytetrafluoroethylene samples, and the adsorption site for water vapour and the weight loss of the sample increase linearly with treated time.

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The wettability of polytetrafluoroethylene was studied from the measurements of the contact angle by the drop method for the untreated and treated films by the sodium-naphthalenetetrahydrofuran and the sodium-liquid ammonia. The contact angle of water on the films skived for practical use depends on the direction of spreading, the advancing contact angle measured in the direction perpendicular to the grooves is 115°and that in the direction parallel to the grooves is 108°.
The contact angle has the constant value approximately 52° on the surface treated by the sodium-naphthalene-tetrahydrofuran for various conditions of the treatment, but on the surface treated by sodium-liquid ammonia the contact angle depends considerably upon the conditions of the treatment, especially upon the treated time and the treated temperature.
This difference seems to be attributable to the differences in the distribution of the adsorption sites for water molecules and the surface roughness.

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For the purpose of studying the ligt scattering of polyacrylonitrile in dimethylformamide, the fluorescence and refractive index of the solution were measured. Intensity of the fluorescence is affected by the condition of the polymerization and the molecular weight of the polymer. The polymers prepared with Redox catalysts exhibit more intensive fluorescence than those obtained by the pearl polymerization method with α-α′-azobisisobutyronitrile in aqueous phase. Fluorescence per unit weight of the polymer is more intensive in the case of low molecular weight than high molecular weight, although the number of the structural units exhibiting fluorescence in a polymer chain increases with molecular weight of the polymer. Intensity of fluorescence of the solution depend on the wave length of the incident light beam, i. e., it is very high at λ=365mμ, decreases with increasing λ value and is almost zero at λ=546 mμ. From these data, it is evident that the effect of fluorescence on light scattering measurement can be neglected if the wave length, 546mμ is used. Method for measurement of (∂n/∂c) and the preparation of the sample solution were studied. The obtained value of (∂n/∂c) for polyacrylonitrile in water free dimethlformamide was 0.0874cc/g at 20°C.

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In order to study the effects of molecular weight the drawing properties of coagulated threads of polyacrylonitrile were measured at 100°C. Polyacrylonitrile was prepared by the suspension polymerization method with α, α′-azobisisobutylonitrile as the catalyst. The fractionated samples (M=40, 000-297, 000) were used for the measurements together with the unfractionated samples (Mω=31, 500-269, 000, Mω/Mn=3.0).
The coagulated threads were obtained by extruding the concentrated solutions in 70% nitric acid into the coagulating bath (dilute nitric acid) at 0°C. The results obtained show a maximum draw ratio at Mω=80, 000 and such a tendency was clearly observed especially in the case of the fractionated polymers. The results were discussed from the view of molecular theory.

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By measuring surface tension we investigated the mechanism of the adsorption of polymers by the surface from their aqueous solutions. Usually the surface tension of polymer solutions varies with time. In order to measure the surface tension continuously and accurately, we constructed an improved apparatus for the vertical plate method. Remarkable aging of the surface tension was observed for all of the surface-active solutions measured. The surface tension of the solutions was measured at various concentrations for various polyvinylalcoholsamples. This aging is not simply due to the diffusion of polymer molecules to the surface. Some of the polymer molecules diffuse to the surface almost instantly when the surface is formed. Thus the polymer concentration becomes very high in the vicinity of the surface and consequently the diffusion of other polymer molecules is highly retarded. The phenomena of the surface-aging in polymer solutions would be mainly attributed to the mechanism mentioned avove.

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The desolvation processes were investigated for the filaments formed in the coagulating bath consisting of dimethylsulfoxide and water. Following results were obtained.
(A) The liquid composition in the formed filaments gradually approaches to the bath composition. The apparent diffusion constant of the solvent in the desolvation process depends sensitively upon the fine structure of the formed filaments.
(B) The weight swelling ratio of the gel filaments formed in the coagulating bath decreases with the passage of time in the bath.
(C) The content of solvent in the gel filaments decreases as these filaments are drawn.

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It has been known by Taylor's experimen that vortex rings are formed in a liquid flowing between the concentric rotaion cylinders. Effect of kinematic viscosity on these rings are studied by rotating the inner cylinder. At high kinematic viscosity the number of the vortex ring is even which it is odd at low kinematic viscosity.
Only four rings from the surface and four ones from the bottom of the inner cylinder are influenced by the surface and end effects of the inner cylinder, respectively, and by the kine mateic viscosity.

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Copolymerization of acryonitrile (AN) and methyl aclylate (MA) in aqueous medium initiatated by K₂S₂O₈ (KPS)-triethanolamine (TEA) redox system has been investigated by kinetic procedure with dilatometry.
1. The rate of copolymerizationR_pdepends on concentration of KPS, TEA and monomer as follows;
2. Apparent rate of copolymerization has a minimun value at molar ratio of AN: MA=0.95: 0.05
3. The monomer reactivity ratio (MRR) of acrylonitrile (M₁) and methylacrylate (M₂) in aqueous medium at 30°C were obtained by the method of Fineman as follows; r₁=0.86±0.05 r₂=1.25±0.15
Tese values are similar with the reference values oftained by bulk polymerization.
[American Cyanamid Co., “The Chemistry of Acrylonitrile”48 (1951). The Beacon Press Inc., New York., N. Y.]

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The infrared Absorption spectrum of spruce thiolignin was compared with those of methyl derivatives and sodium salt of thiolignin, air-oxidized NaBH₄-reduced thiolignin, as well as with those of some simple model compounds, and the corralation between each absorption band and the chemical structure were discussed. The following results were obtained:
1. C=O bands of carboxyl groups and that of ketone or aldehyde groups overlap in the region between 1650 cm^-1 and 1750cm^-1 and their separation is seems to be difficult.
2. Some >C=C bands exist in the higher frequency region above 1710 cm^-1, it suggests the existence of diketone or aliphatic ketone type structure.
3. The amount of >C=O groups attached directly to benzene ring is estimated at approximetely 0.4 groups per benzene ring, from the observed ratio of intensity of >C=O band to that of 1600 cm^-1 band due to benzene ring vibration, comparing with those of acetovanillon and veratraldehyde.
4. 1080 cm^-1 band and 1045 cm^-1 band are ascribed to alcoholic OH vibration, the intensities of which decreased by methylation.

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Copolymerization was treated by the method of Markoff process. In the case of copolymerization of two components, the relation between moleculor reactisity ratio and stochastic matrix P was dicussed. When P is a regular matrix, an element of its fixed vector tishows the probability in the narrow sense that M_i unit of monomers is found in the polymer chains. P forms a stationary Markoff process, ideal copolymerization may occur. In the case that is a permutation matrix forming the cyclic group of which order is equal to the number of components, copolymerization is complete. If the permutation matrix P is the unit matrix, copolymerization does not occur.

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It was found that the grafted films, which were prepared by γ-irradiation of the high-pressure and low-pressure polyethylene films immersed in styrene, contained a large quantity of polystyrene homopolymer, besides unreacted polyethylene and graft-copolymer. This polystyrene homopolymer could be separated by the dissolution of the grafted film in hot xylene followed by cooling, or by extraction of it with hot dioxane. It was found that:
1) The percentages of the grafted polystyrene to the total polystyrene containing in the film were about 23 and 35 in the case of high and low-pressure polyethylene film, respectively.
2) Both grafted and occluded polystyrenes increased with the increasing irradiation dose, and forming rate of both polymers were almost constant throughout the reaction period.
3) The average molecular weight of the occluded polystyrene homopolymer was about five times as large as that of the polystyrene homopolymer produced in the liquid phase.

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Polyethylene powdered by dissolution-precipitation procedure, was grafted with styrene under γ-ray irradiation. The gelatinized polyethylene in styrene was also irradiated. The weights of the grafted polystyrene was always less than those in the case of polyethylene film (previous report) under the same circumstance, and the product scarcely contained occluded polystyrene homopolymer. The rate of grafting on low-pressure polyethylene was also higher than that of high-pressure one. To seperate graft copolymer form reaction product, the fractional precipitation was performed using xylene-n-propyl alcohol and xylene-triethylene glycol as the solvent-precipitant system. The fractions obtained were checked by the turbidimetric titration and infrared spectra. Since the free polyethylene could not be found in all fractions, the polymer produced was supposed to be graft copolymers. The same results was obtained in the fractional precipitation of the grafted film after extraction of the occluded polystyrene.

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For the purpose of elucidating the mechanism of thermal degradation of polyvinyl alcohol (PVA), the compositions of degradation products of PVA were investigated. Infraredspectra and elemental analysis of the PVA film treated in vacuo did not differ greatly from those of the original. In the presence of air, it colored considerably and showed a significant increase in intensity of the absorption band due to >C=O.
Acetaldehyde, crotonaldehyde, benzaldehyde, acetophenone and water were indentified in the degradation products of powdered PVA in vacuo, in nitrogen and in air, the quantities of these compounds being different. The presence of phenolic compounds were also inferred.The residue obtaind in the thermal degradation of powdered PVA in vacuo colored, and showed the decrease in-OH band and increase in >CO band, the results being different from those of the film. The elemental analysis were greatly different from those of the original.

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The Thermal degradation mechanism of polyvinylalcohol (PVA) is discussed according to the results of investigation about colorisation and degradation at heat treatment.

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