In our previous works the results by GPC were compared with those by light scattering and column chromatography for lowcis-polybutadiene.
In this work calibration curve and M_w-[η] of highcis-polybutadicne were compared with those of low cis-polybutadiene. The following results were obtained;
1) At the same count, intrinsic viscosity of low cis-polybutadiene was slightly higher than that of high cis-polybutadiene.
2) At the same count, molecular weight of low cis-polybutadiene was smaller than that of high cis-polybutadiene.
3) M_w and M_w/M_n, of commercial high cis-polybutadiene were larger than those of commercial low cis-polybutadiene.
4) Chain molecule of low cis-polybutadiene was more flexible than that of high cis-polybutadiene.
5) At the same molecular weights radii of gyration [Rz²]^1/2 of low cis-polybutadiene obtained by light scattering in THF at 25°C were larger than those of high cis-polybutadiene, but at the same count [Rz²]^1/2 of both polybutadienes were substantially equal. From this fact, fractionation by GPC appeared to be based on the extent of molecule in the solution.

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The general Maxwell formula for stress relaxation is: dσ/dt=-σ/τ
(1) It is assumed that τ, a monotonously decreasing function of stress σ, is desribed byτ=τ⁰ (1+aσ+bσ²+cσ³+…)
(2) where a, b, c, …are material constants, 0≥aσ+bσ²+cσ³+…≥-1 and τ⁰ is a relaxation time of the system at small stresses. From eq.(1) and (2) the following equation for the terminal region of relaxation is derived.σ^*/σ⁰≈Be^-t/τ⁰
(3) where σ⁰ is the σ at t=0, σ^* means small stresses under which the general linear viscoelastic theory is applicable and B is a function of σ⁰ and is independent of t. If σ⁰=ηγ(ηγ: shearing rate, η: non-Newtonian viscosity), eq.(3) becomes:σ^*/γ≈ηBe^-t/τ⁰=η^*e^-t/τ0
(4)ηmay be called “a non-Newtonian coefficient in stress relaxation following flow”. The functional form of the non-linear terms of τ, i. e., (aσ+bσ²+cσ³+…) may be estimated asdlogB/dlogσ₀=aσ₀+bσ₀²+cσ₀³…
(5) The above macroscopic formal theory is compared with the theory described by Eyring-Tobolsky and checkd by various non-linear viscoelastic solutions.
Applications of the proposed theory will appear in the next report (II)

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The determination of copolymer composition by infrared spectra was made on the ethylene glycol terephthalate-diethylene glycol terephthalate PET/(DEG) T copolymer over the entire range of composition. The film samples were prepared from o-chlorophenol solutions.
Band assignments for P (DEG) T were given with the aid of preceding investigations on polyethylene glycol and PET.
a) The composition of PET/(DEG) T can be determined from the ratio of optical densities at 2880cm^-1 to that at 2960cm^-1.
b) P (DEG) T has characteristic bands at 2955, 2880, 1378, 1365, 1247, 944 and 710cm^-1.
c) It is specifically observed that the band of P (DEG) T at 1725cm^-1 shows a strong parallel dichroism when the film is stretched.

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Seventeen kinds of polyesterurethanes were prepared from hydroxyl-end polyethyleneterephthlate prepolymers (ETP) and diisocyanates by polyaddition reaction, and some of their properties were measured. Polymers were white powder which have fiber forming property. These polyesterurethanes had higher solubility and lower melting points than ETP. Melting points of polyesterurethanes were affected by urethane group and high crystallinity of ETP, and these effects on the melting points were depended upon the molecular weight of ETP. When ETP (M_w1320) was used, melting points of polyesterurethanes were affected with the urethane group and kinds of diisocyanates. When ETP (M_w2710) was used, melting points were more affected with the high crystallinity of ETP than with kinds of diisocyanates.

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High resolution NMR studies of a series of poly (vinyl acetates)(PVAcs), which were derived from the specimens of the poly (vinyl alcohols)(PVAs) having the tacticity of gradual transition from isotactic to syndiotactic configurations, were carried out in chloroform solution at 60°Cand at 100Mc/sec.
It was concluded that the observed triplet of acetoxymethyl resonance absorption could be assigned to isotactic (7.98τ), heterotactic (8.00τ) and syndiotactic (8.02τ) triads from lower field. This assignment was different from that of Ramey et al.
Quantitative determinations of tacticity of PVAcs were made on the base of the new assignment. A good correlation was found between tacticity estimated by NMR and the optical density ratio D916/D₈₄₉ of the IR spectra of the parent PVAs. The relationship is represented by the equation:
Syndiotactic diad (%)=72.4×(D₉₁₆/D₈₄₉) ^0.43
According to the NMR determination, PVA derived from poly(vinyl trifluoroacetate), which has been claimed to be syndiotactic, was found to be atactic as well as a commercial product. The highest isotacticity and syndiotacticity of PVAs, which were obtained by the cationic polymerization of vinyl trimethylsilyl ether in the preceding paper, were found to be 91% isotactic and 74% syndiotactic in diad, respectively.
The α- and β-proton resonances of PVAc were examined by the spin-spin decoupling technique. The decoupled spectra of the α- and β-protons showed two singlets, the α-proton resonance at 5.07τ and the β-proton resonance at 8.1τ as was reported by Bovey et al.

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The penultimate effect in the stereospecific polymerization by the homogeneous ionic mechanism is studied by using α-value (Psi/Pii) which is the ratio of the probability of a triad isotactic addition (Pii) and that of a triad heterotactic addition (Psi). The relationship between α-value and the free energy difference of stereoregular addition and heterotactic one is calculated. From Chujyo's treatment, it is clarified the penultimate effect truly exists in the case of the cationicpolymerization of methyl vinyl ether (MVE) and the anionic polymerization of methyl methacrylate (MMA).
After the existence of the penultimate effect was confirmed in the ionic polymerization, the relation between the polymerization conditions and the penultimate effect is studied. In the cationic polymerization of MVE a polar solvent does not affect the penultimate effect. Otherwise, in the anionic polymerization of MMA a polar solvent decreases the penultimate effect. From these results, it is estimated that two kinds of the penultimate effect exist in the ionic polymerization; one is mainly due to the interaction between a counter-ion and a penultimate group and the other is due to only the repulsion of the penultimate group and the incoming monomer irrespective of a counter-ion.

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The photo-induced graft polymerization of styrene to nylon 6 fiber was carried out without photosensitizer, in the presence of air. Nylon 6 fiber and styrene-methanol solution (30vol%) were placed in a quartz reaction vessel and irradiated at 25°C, with light from various light sources, and spectral filters were used to select various wavelength regions of light. Direct sunlight and a high pressure mercury lamp which emitted only the light of the wavelength ength longer than 300mμ, were effective as light source, and the grafting proceeded very readily and efficiently. The light of the wavelength region 300-380mμ was effective in this grafting, and that of the regions shorter than 300mμ had the retarding action to the grafting. When the effective light source was used, the rate of grafting was proportional to square root of the light intensity.

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