The analysis of pseudoplastic flow in concentric double tube die was performed. The result of analysis was represented as follows:
where the nondimensional term D is a function of two nondimensional terms
as shown in Fig. 3. Using these relations and Fig. 3, the die characteristics of concentric double tube die are easily obtained from the data of dimensions thereof and the flow characteristics of material.

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In practice, many cases are found where the molten plastics flow through divergent or convergent passages.In this study, as a foundamental case, a graphical representation of die characteristics of a circular hole die with slight taper was contrived and was ascertained by the experiment in both flow directions of divergent and convergent. Further it was shown that this graphical representation can also be applied to the combined passage of circuler hole and such with slight taper.

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Phase separation of Polyvinylacetate fractions was studied in methanol, methanol 80: ethanol 20, methanol 60: ethanol 40 and methanol 40: ethanol 60 mixed solvents.It was found that Flory temperature, θ, was 6, 17, 26.5°C and 36°C, respectively, from the relation between critical temperature T_c, and molecular weight M. Then, the intrinsic viscosity was measured in these ideal solvents and it was confirmed that [η]_θ was proportional to M^1/2. was 1.01×10^-3 (at 6°C), 0.97×10^-3 (at 17°C), and 0.91×10^-3 (at 26.5°C) respectively. The results obtained as to the extension of the chain molecule show:(1) The degree of stiffness of polyvinylacetate at the ideal configuration lies between polystyrene and polymethylmethacrylate.(2) Both in aceton and methanol at 30°C, polyvinylacetate molecule expands 3 and 2.5 times in the linear dimensions as compared with the values calculated assuming free rotation about the single bond of the chain.Thermodynamical parameters were discussed.

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The electrostatic potential of a spherical mz: cro-ion, in which the electric charges were assumed to be uniformely distributed, was calculated, taking account of the distribution and volume effects of macro-ions with the aid of Wicke-Eigen's theory.The thermodynamic quantities, such as activity coefficients and osmotic coefficient, are found to have a tendency of decreasing with the polymer concentration and of increasing through a minimum.In addition, this treatment leads us to the formulation of the “activity coefficient of macroions”.

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Load-elongation diagrams of eight kinds of textile fibers under various temperatures, 10-60°C, and humidities, 35-90% RH, have been obtained through the tensile tests. And seven tensile characteristic values, such as 1st modulus of elasticity, 2nd modulus of elasticity, yield points, yield elongation, yield part elongation, tensile strength and total elongation, have been measured by analising those load-elongation diagrams. Authors have tried to represent quantitatively the influence degree of temperature and humidity upon those tensile characteristic values. Cotton, silk, wool, viscose rayon, bemberg, acetate, nylon and vinylon fibers have been tested as single filament for the experiments.

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Measurements have been made of the osmotic pressure of unfractionated and fractionated polystyrene in benzene by modified Zimm-Meyerson osmometer.Relations among the number average molecular weight M_n calculated from the osmotic measurements, M_v, from the solution viscosity and M_SD from the ultra-centrifuge measurement have been examined. Generally speaking, M_n has been remarkably smaller than M_SD, when we determined M_n from osmotic measurement by using the denitrated collodion membrane with low specific permeability. While, with carefully fractionated samples and by using the membrane with high specific permeability, M_n was found to have almost equal value with M_v. It is concluded that the value of M_n is rather sensitive to the method of fractionation.

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The osmotic pressures of the fractionated polymethylmethacrylate (PMMA) in acetone and benzene solutions have been measured by the modified Zimm-Meyerson osmometer with gellcellophane membrane. The viscosities of these solutions have been measured at the same time. The number average molecular weight M_n of PMMA obtained from the acetone solutions is greater than that of the benzene solutions. On the contrary, viscosity average molecular weight M_v of the polymer obtained from acetone solutions is smaller than that from benzene solutions. It seems that these phenomena are explained by supposing that benzene is more good solvent. It is found that the intrinsic viscosity at 25°C[η]_25°C is related to the number average molecular weight as for acetone solution and as for benzene solution. However, former relation found in acetone solution is apparent, and therefore, later equation found in benzene solution is more reliable.

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Viscosities of concentrated solutions of acrylonitrile-methyl acrylate copolymers (methyl acrylate contents in copolymers were 3-5%) in dimethyl formamide were measured by a rotational viscometer (so-called B-type viscometer).The stability of the solution was examined viscometrically under various conditions of dissolution.The stable and molecular-dispersed solutions of this polymer does not show much increase in viscosity with time.The effect of rate of shear upon the viscosity of solution can be written as follows:
is the rpm of viscometer and k and n are constants. It has been found that the different values of viscosity were obtained for various types of polymers of the same M_n. The relationship between viscosity and concentration of the solution, temperature and molecular weight of polymer can be expressed respectively as follows:
1.(The influence of the concentration of the solution)
2.(The influence of molecular weight of polymer)
3.(The influence of temperature)
The apparent activation energy of flow is not constant but varies with the concentration of the solution and with the molecular weight of the polymer.

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The apparent inconsistency of the pronounced temperature dependence of the observed second moment of resonance line with the essential constancy of its theoretical value given by Anderson and Kubo-Tomita is solved by noting the fact, that the observed moment is not such a complete one as the theory predicts, because the observed one is always obtained through cutting off the long tails of absorption line, and its behavior is similar to the motional narrowing of the line width when the temperature changes.The approximate way of Gutowsky-Pake for estimating the second moment when the nuclei are under axial rotations is examined, and its validity is shown to be confined to the case where the correlation time due to the rotation is much shorter than the time scale corresponding to square root of the rigid second moment value.

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Methyl vinyl ether could be polymerized into crystallizable polymer by the activation polymerization with toluene as well as some hydrogen-containing halogenated alkanes. Some signification may be attached in which the special functions of the activation by such a solvent as toluene are dissolution of polymer obtained and also the prevention of stopping the reaction. By this method the non-tacky polymers have been obtained irrespectively with either homogeneous or heterogeneous systems in n-hexane-chloroform or n-hexane-toluene mixtures at -78°C. Almost the same values of densities and the same patterns of X-ray diagrams were recognized in four cases of polymers obtained above. Polymethyl vinyl ether thus obtained were found to be in the same isotactic structure as that of polyisobutyl vinyl ether already reported.

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The effects of kinds of catalysts were studied in the cationic polymerization of styrene. In benzene or benzene-ethylene dichloride solvents at 30°C, the rates of polymerization decrease in the following order, TiCl₄>SnCl₄>BF₃·O (C₂H₅) ₂, but the molecular weights of polymer were in the reverse one, TiCl₄<SnCl₄<FeCl₈<BF₃·O (C₂H₅) ₂.The most active catalyst gave the polymer having the lowest molecular weight.The molecular weights of polymers could be changed by using different kinds of catalysts, and so it was qualitatively shown that the counterion produced from catalyst gave influence upon the other elementary reactions as well as the initiation reaction.

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Polymerization of isobutylene in liquid sulphur dioxide was carried out with aluminum chloride as the catalyst. Solubilities of aluminum chloride in liquid sulphur dioxide and methyl chloride at low themperatures, were determined by gravimetry. These values of solubility were rather small than expected, though they were including suspensoid of aluminum chloride besides the truely dissolved molecule (cf. Fig. 1). Isobutylene was added dropwise into sulphur dioxide solution of aluminum chlorid at -70 to -75°C and polymerized instantly. The catalyst was consumed rapidly. So that added isobutylene was not polymerized after the early temperature rise was extinguished, and recovered as the azeotropic distillate with sulphur dioxide. This distillate was able to polymerize with new catalyst solution.If the catalyst was absent, no poly-(isobutylene) was made. The polymerization degrees of obtained polymer were obtained as 100 to 180, using the Sakaguchi, Nakajima and Sakurada's equation.

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It was mentioned in the preceeding report, that a very small quantity of white powder was precipitated by addition of isobutylene in liquid sulpher dioxide, when the catalyst of aluminum chloride was absent. Then it was afraid that the mixing of this powder, which might be polyisobutylenesulphone, in polyisobutylene made in liquid sulpher dioxide. Polyisobutylenesulphone were prepared from isobutylene and liquid sulphur dioxide by catalysts of peroxides, such as ether peroxide, benzoyl peroxide and potassium persulphate, and they were determined by chemical and infra-red absorption spectroscopic analysis. Infra-red absorption spectra of them and polyisobutylene were taken. One of the two samples of polyisobutylene was washed, after polymerized, sufficiently by methyl alcohol, and the other was prepared as the former, then dissolved in benzene, filtered, and precipitated by methyl alcohol.Both spectra of polyisobutylene were the same, and there were no absorptions corresponding to sulphone radical in them. From this result, above anxiety of the mixing of impurity in polyisobutylene, prepared in liquid sulphur dioxide, was dissolved.

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Methylol reaction (Hydroxymethylation) is the first step of amino resin formation. The kinetic studies of methylol reaction of melamine (or urea) are very complicated, because the condensation products are usualy composed with some of methylol melamines (or ureas) having different numbers of methylol groups. In order to avoid trouble and simplify the treatment, the following reaction rate equation was suggested based on a hypotheses that the rate constants of methylol reaction of every stage are equal, dx/dt=k (am-x)(f-x)-k′x where m and f is initial concentrations (mol/l) of melamine and formaldehyde, x is concentration of reacted formaldehyde as methylol group at time t, and k, k′ are rate constants of normal and reverse reaction. In this equation, the value of “a” meant the functionality of melamine (or urea) aginst formaldehyde and was chosen so as to make the equilibrium constant K (=k/k′) equal at any methylol reaction of different molar ratio (f/m). The value of “a” for melamine here obtained was 6 and that for urea was 2.4. Thus, the rate constants k for melamine was measured at the condition of molar ratio 3, pH 9.2-9.4, reaction temperature 30, 40, 50, 60°C, and activation energy obtained here was 22.3 kcal/mol and reaction heat 4.5kcal/mol.

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α-Methylstyrene was polymerized in the mixed solvents of n-hexane-toluene or n-hexanechloroform catalyzed by BF₃·O (C₂H₅) ₂. In the polymerization at -78°C, the rates of polymerization and the intrinsic viscosities of polymers had the maximum values at the definite solvent compositions. It was also found that the molecular weights of polymers could easily be controlled in a wide range only by changing the composition of mixed solvents. In the case of higher concentration of chloroform in mixed solvents, polymers were found to be partially insoluble in benzene at room temperature. In the polymerization at 20°C, the phenomena described above were not obserbed.

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Two different kinds of viscose rayons, BX yarn and an experimental all-skin type cord rayon, were subjected to the swelling cycle in aqueous alkali of varying concentration, followed by acid hydrolysis. Weight loss during each process and the leveling-off DP were determined. Electron microscopical examination revealed remarkable changes having occurred in the sharpe and size of hydrolysis crystallites. It was also found that the alkali treatment gave rise to a pronounced increase of the leveling-off DP, closely corresponding to the microscopical findings. Based on the experimental data obtained, it was concluded that the observed dimensional changes of hydrolysis crystallite were not due to simple elongation of individual crystallites, but due to joining together of crystallites lying in sequence on the same microfibrils. Since the character and/or the magnitude of the change caused by alkali swelling are considered to vary from fiber to fiber, the hydrolytic method combined with alkali pretreatment, such as employed here, will be a promising means to elucidate the structure originally existing in each kind of various regenerated cellulose fibers.

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In the previous report, one of the authors has found that polyvinyl alcohol (PVA) depolymerizes successively from the carbonyl end-group and yields acetaldehyde through a reverse aldol condensation reaction, when it is heated in its alkaline solution. If PVA contained ketonic group in its main chain, a degradation reaction at the β-keto-oxy group would be expected. By oxidizing PVA by several methods, PVA with ketonic group in its main chain was obtained. Using several samples of the oxidized PVA, the degradation was ascertained quantitatively and the following relations were found,
1/P=αα₀+1/P₀
α=100 (1/P-1/P₀)(1+1/α) +C
where P₀ is the degree of polymerization of the oxidized PVA, α₀ the carbonyl content (mol%) of it except the carbonyl end group content C which is assumed to be equal with the carbonyl content of the original PVA before oxidation, P the degree of polymerization and α the carbonyl content after the degradation.

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To discuss the thermodynamic properties of the polyelectrolyte in solution, crosslinked poly (vinyl alcohol) partially acetalized with glyoxylic acid, denoting it by PVAc, was synthesized with the following procedures: vinyl acetate was polymerized under the addition of divinyl ether prepared from ethylene chlorhydrine; the polymerization product was then saponified with sodium hydroxyde; the crosslinked poly (vinyl alcohol) thus obtained was then acetalized with glyoxylic acid.With the method above mentioned, the crosslinked PVAc with the degree of polymerization between adjacent crosslinkages of 500 and 640, containing 0, 2 and 10 mol% of glyoxylic acid in the chains, were obtained.

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Several polyvinylalcohols having one to two aldehyde group per one molecule (D-PVA) were prepared by cleavage of 1, 2-glycol bonds in polyvinylalcohol with periodic acid. The intermolecular acetal formation was carried out in water under existence of acid catalyst, and the viscosity change of solution with reaction time was measured. After a certain time the solution becomes a gel which is insoluble in boiling water. The time to gel decreases with increase of aldehyde group per one D-PVA molecule at the same condition, and with increase of concentration of D-PVA at the same sample.

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