In order to investigate the orientation mechanism during the melt spinning process of nylon 6 fibers, some properties, such as birefringence, X-ray diffraction, density, shrinkage in boiling water and longitudinal swelling, were measured for the nylon 6 filaments meltspun at various spinning speeds, ranging from 500 to 4400m/min. The following results were obtained:
1) The crystalline orientation measured by the X-ray method increases rapidly with the spinning speed in a range of relatively low spinning speeds, and it attains more than 80% of ideal orientation at the spinning speed of 2000m/min. On the contrary, the total orientation evaluated from the birefringence is much lower than the crystalline orientation.
2) The shrinkage in boiling water passes a minimum at the spinning speed around 1500-2000m/min, then gradually increases and attains an equilibrium value, with the increase of spinning speed.
3) The longitudinal swelling attains a maximum value at the spinning speed around 1500-2000m/min.
The phenomena 2) and 3) are very similar to those which have been observed on the drawing process of nylon 6 fibers, and they are thought to support an idea that in the melt spinning process as well as in the drawing process, the fiber structure becomes most unstable at the intermediate stage, corresponding to the spinning speed around 1500-2000m/min.

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PVC containing azide group (I) was obtained by the reaction of PVC with sodium azide in liquid ammonia or aqueous dimethylformamide.
I was more easily crosslinked on heating with increasing of azide group content and the activation energy of this crosslinking reaction was found to be 23-24 kcal/mole.
The blends of I with elastomers as liquid Thiokol, ABS or MBS rubber were crosslinked with each elastomer through the radicals formed by the thermal decomposition of azide groups.
The elongation at break and tensile impact properties as well as the tensile strength of the crosslinked polymer was improved.

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A new approach for determining unperturbed dimension of polymeric chains from intrinsic viscosity and molecular weight data has been proposed when the parameters K_m and a in the Mark-Houwink-Sakurada (M-H-S) equation [η]=^K_mMa are not constants over wide range of molecular weight investigated. Several pairs of K_m and a in the M-H-S equation, each of which was computed for varying range of molecular weight adequately chosen, have been applied to the treatments in the previous papers (for example, K. Kamide et al.:Chem. High Polymers, Japan20, 512 (1963), 21, 682 (1964), 23, 1 (1966)) with slight modification. Validity of the approach has been examined in the case of poly (vinyl acetate) and poly (styrene) solutions.

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The successive precipitational fractionation from a dilute solution of macromolecules having a most probable distribution was simulated by electronic computor IBM system/360 H 50. The solution theory by Flory-Huggins was used as the principal basis for fractionation. Both a partition parameter σ between polymer-rich and polymer-lean phases, and their volume ratio R increase with decrease of starting concentration, when the same amount of fraction is precipitated. The effect of starting concentratian in the range from 0.001%, to 1.0%(volume concentration) on the distribution of the fractions was discussed. The approximation by using normal distribution is more adequate than that by using Schulz-Zimm distribution for the analysis of the distribution of fractions even in the case of fractionation starting from lower concentration. The approximation by using equilateral triangleshape distribution proposed in the previous paper (K. Kamide et al.:Chem. High Polymers, Japan, 26, 440 (1968)) is useful irrespective of starting concentration. The broadness of distribution of the fractions increases with decreasing the amount of fraction.σ rather thanRis proved to be a more reasonable parameter for representing the efficiency of fractionation. Reversal of average-degree of polymerization of fractions in the process of fractionation, which is occasionally observed in experiments, can not be expected theoretically to occur if thermodynamic equilibrium is attained between the two phases. Refractionation procedure is not effective when the distribution curve of the original polymer is plotted by use of the Schulz's method, but it is useful to obtain sharper fractions.

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The graft-polymerization of methyl methacrylate (MMA) by γ-ray irradiation on the surface of flaky glass has been investigated. It was found that the graft-polymerization of MMA on the alumino-silicate glass occurred upon irradiation at room temperature (or-196°C) only when the latter was previously treated with K₂Cr₂O₇-H₂SO₄solution, In the case that alkaline-silicate glass or silica powder was used, the grafting was not observed. IR spectrum, pyrolysis curve and gas chromatogram were run to prove the grafting. IR absorption band at 1720cm^-1of the grafted glasses was assigned to the carbonyl group of poly-MMA, and the gas chromatogram of the pyrolyzate was identical with that of a commercial poly MMA.
ESR spectrum was taken to investigate the defects in the glass produced by γ-ray irradiation. The spectrum of the irradiated alumino-silicate glass pretreated with K₂Cr₂O₇-H₂SO₄ solution showed the lines with six hfs peaks spaced equally (20.6G) whose center was at g=2.003. No such characteristic resonance lines were found in the ESR spectrum of other glass samples. This result clearly indicates that the defect is electron center trapped at three-coordinated aluminum which is formed by losing one oxygen from the tetrahedron shaped AlO₄lattice.
The relation between irradiation defects and graft-polymerization, and role of the treatments were discussed.

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Distribution of molecular weight of polymers obtained by solid state polymerization was calculated theoretically. In this calculation, three rate constants, k_p for propagation, k_q for chain transfer and k_s for uni-molecular termination were simply introduced. The distribution of molecular weight for post-polymerization was calculated firstly, and then the distribution for in-source-polymerization was derived as the superposition of distributions obtained in post-polymerizations which start at different times.
It was shown in the theory that two peaks in the distribution can be expected if the chain transfer reaction takes place during polymerization. On the other hand, it was indicated that the mechanism of solid state polymerization can be explained by the calculated distribution of molecular weight.

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The emulsion polymerization of vinyl acetate (VAc) was carried out in a water-bath (at 70°C), using potassium persulfate as an initiator and Rapisol (sodium dialkyl sulfosuccinate) as an emulsifier. The influence of the following monnmer-addition techniques upon the timetemerature curve was investigated: A) One-third of the total amount of VAc is charged initially, and the remaining monomer is added dropwise after the polymerization of the initially-charged monomer is complete. B) While the polymerization of the initially-charged monomer (1/3 of the total amount) is proceeding, dropwise addition of the remaining monomer is commenced. C) A whole amount of monomer is added dropwise.
The temperature in the flask was calculated by modifying the method described in the previous paper. A comparison of the observed time-temperature curves with the above calculated ones indicates that the reflux of VAc-H₂O azeotrope mixture has significant effect on the temperature in the flask.
The reflux in these systems was found to occur at lower concentrations of free monomer than those in the emulsion polymerization where whole amount of monomer is charged initially. The critical concentration at which the reflux ceases depends upon the rate of polymerization of the monomer, the rate of monomer-dripping and the period commencing monomer-dripping.
The time-temperature curves for the emulsion polymerization by the dropwise addition of VAc are classified into four types, and a monomer-addition technique in order to minimize the temperature change during the polymerization is proposed from the above classification.

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Ionic crosslinking reaction was carried out in latex emulsions of buthyl acrylate methacrylic acid copolymers or ethyl acrylate methacrylic acid copolymers, using zinc acetate as the water soluble vucanizing agent. The results were as follows:
1) When only free metallic cations were dispersed in the carboxylic emulsions, ionic crosslinking reaction occurred.
2) Polymer gel-solvent interaction coefficient x₁ was calculated, and the number of network chains was estimated from the theory of swelling by Flory and Rehner.
3) Ionic crosslinking reaction was very fast and had no dependency on the crosslinking time and temperature.
4) The density of crosslinking increased nearly proportionally to the zinc content introduced in to the polymer.
5) The degree of crosslinking increased with the increase of diameter of emulsion particles of the polymer.
6) PH of the latex had no obvious effect on the degree of crosslinking.
7) Films of ionically crosslinked products had excellent Young's modulus and tensile strength.

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Isobutyl vinyl ether was polymerized with hydrogen chloride in the presence of metals or metallic compounds in toluene at 0-30°C. The polymer was not obtained with hydrogen chloride alone, while the fast polymerization occured in the presence of the second catalyst components, such as metals, metal oxides and metal salts, which were insoluble in organic solvents.
A possible initiation mechanism was proposed as follows:
_??_
where Me represents metals or their compounds. In this scheme, Me behaves as the adsorption bed for the chloride ion to facilitate the dissociation of hydrogen chloride and to retard the rapid reaction between the growing polymer cation and the chloride ion. The observed changes in the yield and specific viscosity of the resulting polymers for various catalyst systems may be due to the different degree of interaction between these solid materials and the chloride ion.
The system HCl-Ni₂O₃ was the most effective catalyst and produced a high molecular weight polymer. The system HCl-pulverized glass also showed the catalyst activity.

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The graft copolymerization of methyl methacrylate and butadiene to cellulose without radical initiators was investigated. Both chemical analysis and infrared specta were determined, in order to get some informations concerning with the structure of the grafts.
The results showed that the alternating copolymer of methyl methacrylate-butadiene graft cellulose may be formed under the most favorable conditions, in which the monomer ratio of MMA/Butadiene is 30/70 and the reaction temperature is 90°C.
A reaction mechanism is proposed. This reaction is diffusion-controlled and overall activation energy of the polymerization was estimated as 36kcal/mole.

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The reaction of polynonamethyleneurea with ethyleneoxide or propyleneoxide was carried out in atmospheric liquid phase or under pressure. The determination of nitrogen and ether linkages showed that acids had less catalytic effect on the reaction than alkalis, and that the reaction required long time to obtain products of high etherification degree owing to the strong hydrogen bond of polynonamethyleneurea. X-ray diffraction indicated that ethylene oxide was presumed to graft to the amorphous part of polynonamethyleneurea. The moisture absorption of the addition products was higher than that of polynonamethyleneurea. The addition products had remarkedly high melting point. For example, the product with 34.24% of oxyethylation degree melt at 190°C.
The addition products was not soluble in m-eresol, sulfric acid, while polynonamethyleneurea was soluble. The addition products swelled in phenol, glacical acetic acid, hydrochloric acid, while polynonamethyleneurea was not soluble.

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Several new β-oxyalkyl acrylates (I-VI) were prepared by the trimethylphenylammonium iodide-catalyzed reactions of acrylic acid with some epoxides having branched alkyl, phenyl, cyclohexyl, or N, N-dialkylamino group. Their polymerization was carried out in bulk orin benzen solution using 2, 2'-azobisisobutyronitrile as an initiator. In contrast with normal polyacrylates, these polymers showed good solubilities in hydrophilic solvents, which probably arised from the existence of hydroxyl groups. Some polymer reactions on hydroxyl and dialkylamino groups were also attemped. Among them, a cross-linked reaction with TDI gave a hard glass-like resin.

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