Physical properties of polyenanthamide (nylon 7) and polypelargonamide (nylon 9) which were prepared by the polycondensation of the corresponding ω-amino acids have been investigated.
The melting points (T_m) and glass transition temperature (T_g) of these polyamides were measured by a dilatometric method as 223°C (T_m), 52°C (T_g) for nylon 7 and 210°C (T_m), 46°C (T_g) for nylon 9.
The refractive indices of the isotropic sampless (unstretched filaments) were evaluated as 1.526 (nylon 7) and 1.521 (nylon 9). The maximum degree of birefringences, Δn (max) were 0.058 (nylon 7) and 0.064 (nylon 9).
The films of these polyamides were prepared from the formic acid solution. The crystallinity of film samples were measured by the three different methods (IR, X-ray, and density). The relation between the crystallinities and the specific volumes of these polyamides are expressed by the following equations;
α=7.94-8.33v (nylon 7)
α=8.30-8.47v (nylon 9)
in whichvdenotes the specific volume at 25°C.

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The stationary rate of propylene polymerization with titanium trichloride-triethyl-aluminum catalyst has been expressed byr=Ae^-10kcal/RTwhere P is the pressure of propylene, G the weight of titanium trichloride and A the frequency factor, of which A has been discussed here. From the experimental values of the rate and the specific surface area of the commercial titanium trichloride catalysts measured by BET method, we have 10²²-10²⁸ molecules/cm² sec for the values of A. That is close to the surface collision number of propylene, Z=1.4×10²² molecules/cm² sec, at P=1 atm and T=300°C K, which is given by Herz-Knudsen equation. Then the above rate equation may be apparently represented byr=ZSe^-10kcal/RTwhere S is the total area of the solid catalyst used. Applying the absolute rate theory of heterogeneous reaction to the latter equation, the reaction mechanism has been discussed. The most appropriating model of the polymerization is a Twigg-Rideal type, i. e., the simple collision of a propylene monomer to one of the polymerization center which covers the whole surface. Here, “the simple collision” means that the proplene in the activated complex has the same internal motions as that of gaseous propylene. Excepting some special model, the usual Langmuir-Hinshelwood type, i. e., the reaction between adsorbed propylene and polymerization center, can not explain the experimental result.

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Carrying out the propylene polymerization with titanium trichloride-triethyl aluminum catalyst under the usual condition (Al/Ti=1, 10-60°, and 550-740 mm Hg), we have the following kinetic equation for the decreasing part of the polymerization rate.
_??_
with
_??_
where v_∞ is the stationary rate, P the pressure of propylene, τ the polymerization time, f, k₀ and B₀ are constant. This gives
_??_
for the polymerization time τ_4/3, at which the rate v equals to 4/3v_∞. The latter is the same form as that for τ_4/3 reported by Natta and Pasquon who examined an increasing type of the polymerization rate, excepting the energy is 10 kcal/mol. It has been pointed out that there may be a common kinetic law
_??_
for the both changes of the rate in the initial stages of the polymerization.

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The effect of polyvinyl alcohol (PVA) added after polymerization on polyvinyl acetate (PVAc) emulsion obtained in the system having no protective colloids were studied in regard to coagulation by sodium sulfate. Both PVA emulsion and PVAc emulsion, in which perfectly saponified PVAc and partially acetylated PVA were added were easily coagulated by sodium sulfate. But emulsion in which partially saponified PVAc was added had the excellent stability against sodium sulfate. With partially saponified PVAc obtained by ordinary alkali saponification of PVAc in methanol, the effect of the stability against sodium sulfate became higher as the residual acetyl content were increased and the residual acetyl groups were maldistributed in a polymer chain. It was concluded that partially saponified PVAc having the residual acetyl groups maldistributed in a polymer chain absorbed on the surface of the particles of PVAc and the hydrophilic phase were formed on the surface of the particles of PVAc by the hydroxyl groups maldistributed in a polymer chain of partially saponified PVAc absorbed.

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The effect of polyvinyl alcohol (PVA) added before polymerization on the particles, viscosity of polyvinyl acetate (PVAc) emulsion and the stability of PVAc emulsion against sodium sulfate were studied. PVAc emulsion used partially saponified PVAc which was obtained by ordinary alkali saponification of PVAc in methanol had the smaller particles, the higher viscosity and the more excellent stability against sodium sulfate in compared with PVAc emulsion which par fectly saponified PVAc and partially acetylated PVA were used. These effect of partially saponified PVAc exhibited more remarkably as the residual acetyl content were increased and the residual acetyl groups were maldistributed in a polymer chain.

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Cationic telomerization of styrene was carried out by using both acetic acid and paraformaldehyde. The measurement of IR spectra, molecular weight given in the Rust method, and saponification equivalent of the telomers obtained show clearly that these telomers are mostly diacetate which contains one to five units of styrene. These diacetates were saponified with alcoholic potassium hydroxide to afford glycol. The reaction of these glycols with 2, 4-toluene diisocyanate or hexamethylene diisocyanate gave brittle resinous polyurethanes. The intrinsic viscosity of these polyurethanes in toluene was 0.04 to 0.13 at 30°C. The result supports the view that these styrene telomers obtained have bifunctional hydroxy groups approximately.

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Cationic telomerization of isoprene was investigated with the catalytic system consisting of paraformaldehyde, acetic acid and BF3 etherate. The telomers obtained possessed 1 to 15 units of isoprene, 0.5-3.7 units of acetate group and others. Both the number of acetate group per mole and average molecular weight of the telomer were found to be increased by using acetic anhydride. The best condition for the telomerization reaction to obtain the telomer having the structure of diacetate with high molecular weight were studied, and some mechanisms of the telomerization were postulated on the base of the experimental results. Glycol of polyisoprene was able to obtain by saponification of the diacetate and was found to react easily with diisocyanate to give resinous polyurethane. The addition polymer of diisocyanate, polytetramethyleneglycol and glycol of polyisoprene has been found to show good vulcanization properties for conventional sulfur vulcanization.

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