Poly-α-amino acids having high molecular weight to be spinnable have not yet beenprepared except by NCA method. The preparations of poly-α-amino acids are preciselyexplained about the applicable amino acids to NCA method. The studies on poly-α-aminoacid fibers by du Pont or Courtaulds Co. were ceased several years ago but the studiesin our country have been continued even after their abandons and most developed now inthe world. Poly-γ-methyl glutamate is used in the field of synthetic leather.
It is necessary for the spinning of polyamino acids to be considered the change of second-ary structure of molecules, which is very different from the spinning of ordinary artificialor synthetic fibers, and this consideration is also fit to the spinning of protein fibers. Theappearance of a new type of synthetic animal fibers with variable charactors would be ex-pected by the use of the secondary structure of fiber molecules of poly-α-amino acid.

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Copolymerization of vinyl chloride (VC=M₁) with vinylene carbonate (M₂) was studiedunder different conditions. The monomer reactivity ratios were obtained as γ1=13.0; γ2=0.0 at 60°C, and these values were found to be dependent on the temperature.
Dehydrochlorination of the copolymer showed the behavior similar to the case of PVC. The copolymers obtained were all hard and brittle.
Terpolymerization of VC, vinylene carbonate and maleic anhydride afforded methanolsolule copolymers.

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Aromatic poly-N-methylhydrazide was prepared by polycondensation reaction of dimethyl terephthalate with hydrazine sulfate in fuming sulfuric acid prior to investigation of various properties. The thermal behavior of the polymer has been investigated using differential thermometric and thermogravimetric techniques. In addition, the polymer film properties, such as mechanical, electrical, physical, and chemical, have extensively been studied. The aromatic poly-N-methylhydrazide showed a fair degree of thermal stability, but its electrical propeties were resemble to those of 6-nylon.

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Polymerizations of 1, 3-methylethylcyclopentadiene (MECPD) and 1, 3-methylisopropylcyclopentadiene (MPCPD) were carried out with various Friedel-Crafts catalysts. MECPD polymerized more readily and gave polymers with higher molecular weight than MPCPD. The mode of monomer addition was affected by the size of the substituents, and the ease of the propagation from the alkylsubstituted carbon decreased in the following order: CH₃>CH₂CH₃>CH (CH₃) ₂.
In copolymerization of MECPD (M₁) with cyclopentadiene (M₂), the former showed a high reactivity: r1=4.05±2.02, r2=0.12±0.18. On the other hand, the reactivity of MPCPD was comparable to that of cyclopentadiene.

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The reactions of hydroxymethylated 2-methoxy-4, 6-diamino-s-triazine (MMT) molecules in an acidic aqueous solution were studied kinetically. The average molar number of formaldehyde (F) combined (n) in the samples used were 1.43 (Sample I) and 1.56 (Sample II). The reactions involved are both dissociation of methylol groups and condensation (methylene bond formation) reaction of methylol with amino groups. The reaction rates were measured by employing both iodometric and sulfite methods in pH's varying from 3.56 to 2.75 at 25°C.
The rate of the dissociation reaction v_d and that of the condensation v_c are expressed as follows,
v_d=k_d (na-x-y)
v_c=k_c (na-x-y) (ma-x+y)
where, k_d is the rate constant of the dissociation, a the initial concentration of MMT, na the initial concentration of methylol groups, x the concentration of methylene bonded F, y the concentration of liberated F and amino groups (mol/l, respectively), k_c the rate constant of the condensation reaction, m the average molar number of amino groups and ma the initial concentration of amino groups (mol/l).
Until over ca. 15% of the initial methylol groups condensed, k_d and k_c were nearly constant. The maximum value of k_{c (max)} was obtained at[H₃O⁺]=[H₂O]/K₁ (K₁: the equlibrium constant of the reaction between MMT and acid), and k_d increased with decreasing pH. Then, the rate constant (k) or condensation reaction, for which y was neglected, was examined. In the range of reaction where k was nearly constant, the difference between k_c and k was comparatively small. Consequently, the rate constant of condensation reaction between MMT molecules having n below 1.56 might be represented approximately by k in the initial stage of the reaction.

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In this paper is presented the analysis of non-isothermal crystallization taking place in the process of solidification from molten state of nylon 6 polymer extruded out of die into cooling water to produce the gut. The apparent crystallinity x as the function of cooling time t and temperature θ is given by the following equation for a certain dimensionless radius parameter γ/R .
Where, I: homogeneous nucleation rate, G: spherulite growth rate, i and j: integer number. The proposed equation has been derived on the following assumptions; (a) molecular orientation in the gut is neglible, (b) mode of crystal growth is spherulitic, (c) heat of crystallization is negligible, and (d) the effect of thermal history before nucleation on the crystallization is also negligible.
Further the crystallinity of the crystal structure in the α or γ form (X_a, or X_γ) and the density ρ for various γ/R were calculated.
On the other hand, to investigate the varidity of the proposed equation, the nylon 6 gut was prepared under the similar condition with respect to the cooling as adopted in the theoretical calculation.
It has been demonstrated by observation of the gut with polarized microscope that the assumptions (a) and (b) are valid. The parameter of crystallinity given by the calculation has also been shown to agree well with that derived from the experiment. This will mean that the assumptions (c) and (d) are accepted under the condition in which the cooling rate is around that employed in this study.

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