Hitherto, gas transmission rates of high polymer films were measured by employing a periodic collection of increase of pressure with time. So, permeameter whose simplicity of operation and exactly measurement is to be desired earnestly. Here noted automatic recording permeameter by unbonded strain gage has many points of excellence, such as reproducibility, extreme convenience, a minimum of personal errors, the simplicity of operations and useful analysis of diffusion behavior. Diffusion constant (D), solubility constant (S) and permeability constant (P) of high polymer films were calculated by the early method using the automatic recording chart. D, S and P determined by the late method coincided with the values by the early method except ethylcellulose. For this reason I think the early method is useful not only to reduce measuring time but to check the value by the late method.

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Stress relaxation measurements were carried out at various strains on three cellulose esters (cellulose acetate, cellulose nitrate and cellulose acetate butylate). The individual curves obtained from varying strain measurements appear to be shifted horizontally by appropriate amounts to form a single master relaxation curve.

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The relaxation time spectra were obtained over the relaxation time range from 1×10^-6 to 1×10¹⁶ seconds on three cellulose esters (cellulose acetate, cellulose nitrate and cellulose acetate butyrate). The magnitude of each spectrum is about 1×10⁹ dynes/cm² and a position of peak is observed on each specimen over a relaxation time range extending from 1×10² to 1×10¹⁰ seconds. There is no distinct difference between cellulose nitrate and acetate, but a peak of spectrum of cellulose acetate butyrate is located over a longer relaxation time range than the formers.

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Nylon 6 fibre subjected to dry-heat-and steam-setting, gave the X-ray diffraction suggesting the increase of crystallinity, especially conspicuous on the latter case. And it was comfirmed that the intensity of the spot reflected from the (020) plane was decreased more easily by steam-setting than dry-heat-setting. On the one hand, steam-setting did not so greatly decrease the orientation of crystallites. Therefore, what made the dyeing: property of nylon 6 fibre better, reported on the second part of this series, was found not to be attributed to the decrease of orientation of crystallites.

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The diffusion of poly (vinyl alchohol) partially acetalized with glyoxylic acid in salt-free aqueous solutions has been investigated. In such systems, the diffusion was found to obey Fick's first law. The diffusion constants, diffusion coefficients at zero concentration, increased proportionally to the carboxyl group contents for samples of lower degrees of acetalization, while they were almost independent of the degree of polymerization. The numbers of carboxyl groups estimated from the diffusion constant and the intrinsic viscosity were in good agreement with those obtained from electric conductometry. The fixation of counter ions by polyions was found to be negligibly small in our experiments

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Theory of moving boundary proposed by Longsworth, Dole and Alberty for simple electrolytes was applied to a polyelectrolyte and the charge number was estimated, without assuming the mechanical model of the macro-ion. The material was partially acetalized poly (vinyl alcohol) with glyoxylic acid. It was observed that, a) the charge number was in harmony with the analytical value for the case of low degree of acetalization, b) for the materials of larger degree of acetalization the charge number was in an agreement with the analytical value when higher polymer concentration and lower salt concentration were chosen whereas it was somewhat lower for higher salt concentration. The discrepancy between the calculated and analytical values may be attributed to the disregard of the concentration dependence of polyelectrolyte mobility.

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Among the variables in the extrusion and the stretching process of Saran, the most important factor affecting the mechanical properties of a filament is the stretch ratio. The second, is the temperature of the cooling bath, the third is the stretching temperature and the least important factor is the die temperature. In order to investigate the changes in fine structure of filaments, 40 samples were made under various conditions of the above-mentioned four factors. The following three typical filaments were included in these 40 samples.(1) An isotropic amorphous model filament; this is a typical unoriented filament having no fibrous properties.(2) A standard model filament; this is a commercial Saran filament and is the standard used for comparing the behavior of other samples in stretching and heat treating.(3) An anisotropic crystalline model filament; this is a highly oriented filament prepared under a most severe condition of stretching. It fibrillates easily and its tensile strength is 3-4 g/d; however, its tensile elongation is below 10%.

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The density of Saran filament is measured by the density gradient tube method and the crystallinity is then calculated from the density. The crystallinity of Saran is calculated on the following two assumptions;(1) The crystalline part of Saran filament is pure polyvinylidene chloride.(2) Component of the filament has additive properties. The crystallinity of the standard filament is about 27%. The crystallinity of a filament tends to increase with the increase in stretching ratio, but is almost constant through the wide range of its stretching temperature. However, the crystallinity of a filament increases somewhat by heat treatment and the crystallinity of the anisotropic crystalline filament is about 35%. The crystallinity of a filament that is heat-treated under tension is greater than the crystallinity of a filament that is heat-treated without tension.

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Denisities, infrared and ultraviolet absorption spectra of polyvinyl alcohol films subjected to heat-treatments in silicone oil at various temperatures and time intervals were measured. The density was measured with density gradient tube method. In the cases of the heattreatments at the temperatures lower than 180°C, density and optical density of the 1141 cm^-1 crystallization-sensitive band increase with duration of time of treatment and reach the quasiequilibrium values. On the other hand, in the cases of samples treated at the temperatures higher than 190°C, those curves exhibit maximum values. The results of ultraviolet absorption spectra indicate that the decreases of the density as well as the optical density of the 1141 cm^-1 band of the samples subjected to the heat-treatments at the temperatures higher than 190°C arise from the thermal decomposition of the samples. The effects of the thermal decomposition on the ultraviolet and infrared absorption spectra were found to be more sensitive than that on the density. The density measurements of the samples subjected to heat-treatments at different moisture contents revealed that the density vs relative humidity curves have maximum at certain relative humidity values.

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Free radicals produced from the thermal decompositions of benzoyl peroxide (BPO) and 2, 2′-azo-bis-isobutyronitrile (AIBN) in various solvents were captured by the scavenger, 2, 2-dipheny1-1-picryl hydrazyl (DPPH). From the rate of the fading of DPPH measured by colorimeter, the rate constant of the production of free radicals (fk_d) was obtained. It was observed that the values of fk_d varied with solvents even when the same radical source was used at fixed conditions, and that the effects of oxygen on the measurments were dependent on the combinations of radical sources and solvents used.

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In the previous report, DPPH was used as a scavenger while in the present work, 2, 2-di (p-toly1)-1-picryl hydrazyl (DTPH) was used. DTPH was synthesized from 4, 4′-dimethyl diphenylamine and picryl chloride by the same method used in DPPH. The values of fkd, the rate constant of the production of free radicals, were nearly equal to or slightly lower than those of the previous report. The effect of oxygen on measurements of fkd were similar to that in the case of DPPH, except the system of AIBN-chlorobenzene-DTPH, where a larger effect was observed.

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The structures of polyethylene oxidized by γ-ray irradiation at room temperature have been studied by the measurements of dielectric loss angles and infrared spectra. The values of tanδ of γ-ray oxidized samples have not varied with frequency so much as that of the thermal oxidized samples. It has been found that linear relation exists between log, of tan and log, of oxygen absorption. Moreover, it has been known from infrared analysis that the absorbances of about 2.97 μ and 5.82 μ have increased with oxygen absorption, and the absorbances of 5.82 μ by ketone have been proportional to the amounts of absorbed oxygen. The amounts of ketone found from infrared analysis have been 40-60% of that of the oxygen absorbed. It has been concluded from weight increases, etc., that peroxide bonds have been produced to some extents by γ-ray oxidation.

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Thermally oxidized polyethylene samples have been measured about their dielectric loss angles in the range of 7×10⁴-1×10⁷ c/s. It has been found that linear relation exists between log of tanδ and log of oxygen absorption. Moreover, infrared analysis have been performed on the oxidized samples, and it has been indicated that absorbances of about 2.9 μ and 5.8 μ increase remarkably with oxygen absorption. The increase of absorbance of about 5.8 μ by ketone [CO] has been more eminent, and it has been found that between log of amount of absorbance and log of oxygen absorption exists linear relation. It has been presumed that out of the oxygen absorbed, about 42% as mean value, became ketone. And between log of tan δ and log of amount of ketone existed linear relation. From these results, mechanisms of initial oxidation of polyethylene have been discussed.

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The copolymerizations of acrylamide (M₁) with vinyl acetate (M₂) initiated by 2, 2′-azobisisobutyronitrile were carried out in absolute methanol at 50°C. The compositions of the copolymers obtained from various monomer concentrations were calculated by nitrogen analysis. From these results, monomer reactivity ratios, r₁, r₂ and Q, e values of acrylamide were determined as follows: r₁=7.5, r₂=0.07 Q=1.32, c=+0.79 All of the copolymers obtained from these experiments were soluble in water and transformed into four-component copolymers containing acrylamide, acrylic acid, vinyl acetate and vinyl alcohol by alkali saponification.

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In the cationic polymerization of styrene in low dielectric constant solution with the solvents having equal dielectricconstants, the rate of polymerization was found to be greater in the aromatic solvent than in the aliphatic one. This tendency was always recognized to be the same when water or trichloroacetic acid were used as cocatalysts. The electrostatic effect of the solvents previously reported can not satisfactorily explain these results and so the nonelectrostatic effect must be considered.

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It was observed that with raising polymerization temperature of mother polyvinyl acetate, the turbidity velocity of the aqueous dimethyl sulfoxide solutions of PVA decreased, the degree of swelling in water of PVA increased and the intensity of infra-red absorption at 8.7μ, a crystallization sensitive band, of PVA decreased. In the case of bulk polymerization, the turbidity velocity and the swelling degree varied also with the polymerization conversion.

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In order to confirm the mechnism of the termination reaction in a heterogeneous polymerization of acrylonitrile, three nitroderivatives of phenol; p-nitrophenol, 2, 4-dinitrophenol and picric acid are taken as retarder. The results are as follows; the mono-derivative has no effect, but the reaction rate in the presence of the di-and tri-derivatives measured at 40 and 58°C respectively is proportional to represents the concentration of each nitroderivative, concentration of the monomer and benzoylperoxide being taken as constant. It is also known that the mean molecular weight of the polymer becomes smaller as the picric acid concentration increases. These results indicate that the present chain termination reaction must be of monomolecular.

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The following assumptions were made for the kinetic analysis of the dilute solution polymerization:(a) The solvent transfer reaction occurs vigorously than the other transfer reactions.(b) Although most of the polymer radicals are terminated by transfer with the solvents, some of them are terminated with the solvent radicals. A distinction was drawn kinetically between the resulting polymer molecules which contain initiator fragments and those which do not contain them. In the kinetic treatments, side reactions which affect the stages of polymerization were taken into accounts. The obtained kinetic expressions are in good agreement with the experimental results of Part I. The chain transfer constant of ethanol was estimated to be 1.8×10^-3 at 50°C.

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The polymerization of Acrylonitrile in aqueous solution was studied using a redox catalyst consisting of potassium persulfate and triethanolamine. The purpose of this study was to relate the rate of polymerization and the average polymerization degree of the resulting polymer to the pH of the system. It was observed that the apparent rate of polymerization droped off and average polymerization degree ascended as the pH decreased to 2.0. It would appear that the triethanolamine suggests a equilibrium with hydrogen ion as follows: Thus formed conjugated acid BH⁺ inactivated the facility of triethanolamine as reduction agent, and the apparent rate of polymerization failed and average polymerization degree thus obtained polymer increased because of the concentration of active coactiyator (triethanolamine) was decreased.

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Changes in the infrared spectrum of vinyl acetate by the addition of some metal alkyls were observed. On the addition of triethyl boron to 5% solution of vinyl acetate in hexane, the carbonyl absorption band of vinyl acetate splits into two bands which adsorb at 1754 cm^-1 and 1774 cm^-1 respectively. The ratio of optical densities of these bands reaches its maximum value when the molar ratio between triethyl boron and vinyl acetate is nearly 1: 1. When dimethyl cadmium was added, the gradual decrease of total absorption bands as well as the split of the carbonyl band was observed. And the larger amount of dimethyl cadmium was added, the more split was observed. This is probably due to the interaction of carbonyl groups and dimethyl cadmium, and 1: 1 adduct of vinyl acetate and dimethyl cadmium was isolated and confirmed by analysis. Dimethyl cadmium was also proved to attack the C=O groups of polyvinyl acetate. In the case of triethyl boron, the reason of split occurrence is not known so far, but it is clear that its behaviour markedly differs from that of dimethyl cadmium. It seems likely that zinc and aluminum alkyls behave similarly as cadmium alkyls.

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The increase in the degree of polymerization with conversion has been investigated by measuring the degree of polymerization, the rate of polymerization and the k′ of Huggins. The polymerization was carried out in bulk and butyl acetate solution system. At the about fifteen per cent conversion, the rate of polymerization increases rapidely, but the increase in the degree of polymerization becomes gradual. These results can be explained from the fact that the gel effect becomes conspicuous at about fifteen per cent, and therefore the polymer radicals grows until they are terminated by the chain transfer of monomer. In the bulk polymerization, the degree of polymerization represented in the follow equation: P=760W^0.074 where P is the degree of polymerization and W is conversion (%). The k′ of Huggins did not show remarkable change from the initial stage to final stage, and therefore it is not proper to think that the increase in the degree of polymerization is due to the effect of the branching of polymer.

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