An apparatus for measuring the elastic recovery, exhibited by viscoelastic fluids after the cessation of steady flow, is designed. This is a coaxial double cylinder type viscometer, in which the shaft of the inner cylinder is set free to rotate by an elastic force of the sample immediately after the revolution of the outer cylinder is stopped. By using the concept of internal strain, the following equation can be derived.
_??_(1)
θ_e: angular displacement of inner cylinder caused by the elastic recovery of sample after the cessation of flow, σ_i: shearing stress at the inner cylinder surface, R_i: radius of inner cylinder, R₀: radius of outer cylinder, n, k: constants for the sample.
For Na-PAA solutions eq.(1) agrees with experimental results.
Concentration and temperature dependence of θ_e at various σ_i for Na-PAA was measured.
For the range of 1-2%, n=1/2 and for the region smaller than 1%, n approached to zero.
n=0 means that the strain obeys the Hooke's law in shear.
It is considered that the contribution of orientation entropy to the fluid elasticity of Na-PAA solutions is remarkable, because θ_e is depressed with increasing temperature.
Elastic recovery after the cessation of steady flow, which was a kind of non-linear creep recovery, was observed as a function of time.

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Non-Newtonian flow and fluid elasticity of Na-carboxymethyl cellulose, Na-alginate, methyl cellulose, hydroxyethyl cellulose and Na-carboxymethyl starch solutions were studied with the apparatus (double cylinder viscometer) described in the previous paper.
The experimental results are plotted as logσ_i-logγ_ia, logθ_e-logγ_ia, and logθ_e-logσ_irelationship, where σ_i and γ_ia are the shearing stress and the shearing rate at the inner cylinder surface respectively and θ_e is the angular displacement of the inner cylinder after the cessation of steady flow.
The slopes of the curves described above are employed to evaluate the non-linearity in viscoelastic properties of samples. In general, the slopes varies continuously or discontinuously with shearing rate or stress. These phenomena may be interpretted as a result of continuous or discontinuous shear break-down of secondary structures.
In Na-alginate which seemed to form little secondary structures, and in high consistency Na-carboxymethyl starch and gelatinized methylcellulose which seemed to contain a great deal of secondary structures, θ_e were comparatively small. Hence, it is plausible that there should be an optimum condition secondary structures in these fluids.
In carboxymethyl cellulose and carboxymethyl starch, non-linearity of viscoelasticity and the amount of elastic recovery (θ_e) were influenced profoundly by preparative conditions.

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Vinyl chloride was polymerized by γ-ray irradiation at-78°C, 0°C and 18°C, respectively. The solution properties of the polymer were examined. The polymer polymerized at-78°C was not soluble in tetrahydrofuran at the temperature up to 70°C. The polymer polymerized at 0°C contained small amount of tetrahydrofuran insoluble fraction. The polymer polymerized at 18°C was almost soluble in tetrahydrofuran.
The polymers polymerized at 0°C and 18°C were fractionated by the successive fractional precipitation method, using tetrahydrofrane as solvent and water-tetrahydrofuran mixture as non-solvent. The fractionates were examined osmometrically and viscometrically, and the following equation was obtained.
_??_
The value of K obtained by Kawai and Fixman-Stockmayer's method was 2.11×10^-3. The γ-ray-polymerized polymer, as compared with a commercial polymer, keeps the linear relation up to the higher molecular weight in the Mark-Houwink equation.

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Melt flow behaviors of commercial polyproplylene (viscosity average molecular weight M_v=2.39×105, n-Heptane insolubles, 98.5%) were investigated with a capillary viscometer, Koka Flow Tester, using 8 straight-type dies ranging in the ratio of the length to the radius from 2 to 30 and 5 tapered-dies ranging in the inlet angle from 5° to 90°, at 250°C. Melt flow can be approximately expressed by the two parameter equation, τ=KDⁿ (where, τ, shear stress, D, shear rate, n, constant depending on the non-Newtonian behavior, K, constant). End correction factor ν, determined by Bagley's method, increases linearly from 3 to 12 with increasing ln D from 2.7 to 4 (sec^-1). A method to estimate the effect of end loss at the tapered inletwas proposed. The end loss at tapered inlet shows minimum for 20° tapered die. Constant critical shear stress τ_c=1.1×10⁶ dyne/cm² for straight dies was obtained if the end effect was taken into account.τ_c for tapered die shows maximum at 20°. Bagley's method of estimating the shear modulus of the melt i. e., plots of ν vs.τ, is inapplicable for polypropylene.

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For observation of the transition phenomena in polymers, simple heating photometer was made. The main part of this instrument is set up from the light source with sensitive stabilizer, polarizer, cadmium sulfide photo-conductive cell and the furnace.
Then the results are recorded automatically on the strip chart paper. It can be used to the following purposes;
1) Observation of the melting behaviour in crystalline polymers.
2) Observation of the isothermal crystallization process.
3) Determination of the glass transition in amorphous polymers.

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The effect of amine structure on the pot-life and the cure-time in the formation of the polyurethane, and on the properties of elastomer, were studied.
Ten kinds of diamine having formula I, or II were used as curative for polyurethane prepolymer:
_??_
As the pK_b, of diamine increases, both rates, the pot-life and the cure-time, became faster. And the properties of elastomer were depended upon the molecular rigidity and the steric hindrance of the ortho-substituent to amino group.

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We have studied the moisture effect on ultraviolet oxidation of several kinds of plastic films by the method of tensile strength, elongation and infrared absorption spectrum and found that the oxidative reaction promoted with increasing humidity.
It is probable that the moisture acts as the catalyst of ultraviolet oxidation.

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Accelerated photodegradation of polyethyleneterephthalate (PETP) film have been studied by a weatherometer or by outdoor exposure.
In these degraded samples, the changes in their tensile strength and elongation when irradiated by weatherometer were very slow, while the changes under outdoor exposure were remarkable, especially in summer season.
From the result of measurement of infrared absorption spectrum, melt flow rate, density and accelerated ultraviolet irradiation using various light sources, it was concluded that PETP film is oxidized with random scission of main chain by the short wave length ultraviolet irradiation.

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Radiation-induced solution and bulk polymerization of acrylic anhydride were carried out over a wide range of temperature, for the purpose of studying the effects of temperature, phase, conversion, and initial monomer concentration on the degree of cyclization of the polymer obtained. The degree of cyclization increases with increasing conversion and temperature, and decreases with increasing initial monomer concentration. The degree of cyclization of the polymer formed in solid state at -78°C is similar to that of the polymer obtained in toluene solution at the same temperature. But the polymer formed in solid state is crosslinked. The determination of the residual unsaturation of the polymer by bromometry makes it possible to evaluate the ratio k_p/k_c of the rate constant of vinyl propagation and that of cyclization; for solution polymerization in toluene at 30°C, this ratio is equal to 0.09. Similarly, the difference between the activation energies of vinyl propagation and cyclization is evaluated to be 2.3kcal/mol for solution polymerization in toluene, and 4.7 kcal/mol for bulk polymerization in liquid state, respectively.

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The copolymerization of propylene (monomer 1) and 1-butene (monomer 2) was carried out with Al (C₂H₅) ₃-TiCl₃ catalyst in order to find the reactivity ratios of these monomers and some properties of the copolymer.
From the results of solubility test and IR measurement of the copolymerization product, it was found that copolymer free from both homopolymers was produced. The monomer reactivity ratios were r₁=1.62 and r₂=0.50 in n-heptane at 60°C and at the molar ratio of 1.5: 1 of Al (C₂H₅) ₃-TiCl₃. The solubility of copolymer in n-heptane and ether increased with 1-butene content in the copolymer. All the copolymer containing more than 10 mole % of 1-butene was soluble in n-heptane. The IR spectrum of the copolymer had a new absorption band at 1240 cm^-1, which was not found in polypropylene, poly (1-butene), and their blend. The strength of this absorption band is maximum at 40-50 mole % 1-butene content in copolymer. This band is considered to be characteristics of the propylene-1-butene random copolymer.

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Synthesis of N-vinylacetanilide (VA) by the reaction of acetanilide with acetylene, its polymerization and copolymerization are described.
Rate of vinylation was found to be proportional to the first order both for the catalyst concentration and for the acetylene pressure. Maximum yield of VA was always below 50% under the reaction condition studied, presumably because of some side reactions. Non-polar solvents were preferable for the vinylation to polar solvents.
When homopolymerization of VA was carried out with radical initiator, an amorphous polymer was obtained. With typical cationic, anionic or Ziegler type catalysts, however, no polymerization was observed.Monomer reactivity ratios in the copolymerization of VA with St and with MMA have been determined and Q and e values were calculated as follows:_??_.

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Study was made on the copolymerization of propadiene with ethylene in the presence of catalysts of Ziegler type. The copolymerization proceeded with Al (i-C₄H₉) ₃-VOCl₃, but did not appreciably with Al (i-C₄H₉) ₃-TiCl₄. The optimum molar ratio of Al (i-C₄H₉) ₃ to VOCl₃ was found to be 2.4. The Al (C₂H₅) ₂Cl combined with VOCl₃ brought about the decreases in yield, propadiene content and molecular weight of copolymers.
The copolymerization with varied monomer composition in the presence of Al (i-C₄H₉) ₃-VOCl₃ catalyst, revealed that the yield and molecular weight of polymer decreased with increasing in amount of propadiene, especially very markedly until the propadiene contentexceeded ca. 10%.
This fact was explained in view of the assumption that propadiene, which was shown to be less polymerizable than ethylene, would be more favorably adsorbed on the active sites of catalysts.
From the monomer-copolymer composition curve, the apparent monomer reactivity ratio of propadiene was found to be smaller than that of ethylene.
X-ray diffraction and solubility measurements indicated that the crystallinity of copolymerizatation products was lower than that of homopolymers, suggesting that the resultant polymer did not consist of the mixture of homopolymers, but consisted of the copolymer.

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Acetaldehyde and phenylisocyanate were copolymerized at low temperatures in the presence of various anionic catalysts. The rate of polymerization was remarkably rapid. The obtained polymers were crystalline and their infrared spectra showed that polymers contained polyurethane structure. These copolymers were much more thermally stable than polyacetaldehyde. It was possible to obtain three component copolymers by using living polymers.
Copolymers were prepared similarly from acetaldehyde-ethylisocyanate, -tolylenediisocyanate, and phenylisocyanate-n- or iso-butyraldehyde, -chloral and the thermal stabilities of polyaldehydes were improved by copolymerization.

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Acetaldehyde and glyoxal were copolymerized in the presence of various anionic and cationic catalysts. The polymers were obtained in high yield when glyoxal were polymerized using anionic catalysts, but in low yield when cationic catalysts were used. The glyoxal component rich polymers were obtained when the former catalysts were used, but the polymers contained more acetaldehyde component when the latter catalysts were used. It was possible to obtain three component copolymers by using living polymers by using living polymers. The obtained polymers were amorphous from the results of X-ray diffraction independently of polymerization condition and had softening temperature between 160 and 210°C corresponding to their compositions. The thermal stability of these copolymers was higher than that of polyacetaldehyde.

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