The degradation of polyacrylonitrile in dimethylformamide (DMF) at 90°C has been measured by a viscometric method. It has been shown that the degradation of the polymer is induced by the reaction with dimethylamine in DMF and that the rate of the chain scission reaction is approximately expressed as ds/dt=k (s_f-s), where s is the average number of broken links per one molecule of the original polymer, s_f, the number of the broken bond at the end of the reaction and k, a constant. The apparent activation energy of the reaction was 10.1kcal/mol. Discussions have been given on the mechanism of the chain scission reaction.

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The thermal coloration in the polyacrylonitrile (PAN) solution of dimethylformamide (DMF) was investigated at 90°C and 140°C. At the presence of small amounts of dimethylamine in DMF, a significant coloration takes place at 140°C. In the near ultraviolet spectra of the colored solution, absorptions at 268mμand 365mμand in the infrared spectra of the film prepared from the colored solution, a broad absorption in region 1700-1490 cm^-1 were observed. The coloration is probably due to the condensed ring structure formed by linking up of adjuscent nitrile groups in PAN and it seems that small amounts of dimethylamine in DMF accelerates the formation of the conjugated colored structure.

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The relations between specific volume (V) and crystallinity (X_m) measured by X-ray diffraction method for various polyethylenes at room temperature were studied, and we get the relation (1)
The specific volumes of amorphous and crystalline phases at 20°C obtained by the equation (1) are 1.233cc/g and 1.009cc/g, respectively.
Interplanar spacings of (110) and (200) planes were obtained by the X-ray diffractometer at room temperature, and from these results we computed the values of a and b of the unit cell. The density of crystalline phase ( ) was calculated from such values of a and b, and that of c obtained by Bunn.
The density of amorphous phase ( ) was computed from the following formula
The values of d_a decrease and d_c, tend to increase with increasing of the crystallinity, therefore, the densities of amorphous and crystalline phases obtained by the equation (1) are considered as approximately as the mean value for each sample.
The observed density of amorphous phase with each sample is extrapolated to the zero crystallinity corresponds to the density of completely amorphous polyethylene, and is close to the density obtained by linear extrapolation of specific volume temperature relationship, which is justified above melting point to room temperature.

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When lignin-SBR coprecipitate, dried at room temperature in vacuum, was extracted with saturated hydrocarbon solvent such as cyclohexane, some fraction of SBR was found to be difficult to be extracted although all SBR was extracted quantitatively in the case of dry compounded lignin-SBR mixture. This unextractable SBR fraction was found to be richer in styrene groups, and to have viscometrically higher degree of polymerization than the extracted fraction. Parallel to this findings, from the coprecipitate of lignin and SBR mixtures of low and high content of styrene, SBR of lower styrene content was extracted selectively by benzene. These results correspond to the fact that the equilibrium constant for the formation of hydrogen bond with styrene group is larger than that with ethylenic double bod, which was reported in part 1 of this series. Futhermore, the styrene group in SBR seems to be sterically more favourable to interact with OH groups of lignin than the ethylenic bond in SBR. From the coprecipitate of lignin and a mixture of SBR and NBR, SBR was selectively extracted, so the bond between OH group of lignin and C≡N group of NBR might be stronger than that between lignin and SBR. All these phenomena support the existence of the secondary bonds like OH-π electron.

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Concentrated solution of polyacrylonitrile in 70% nitric acid was extruded in 36% nitric acid and scoured after coagulation. The coagulated threads were stretched at 100°C in hot water.
From X-ray diffraction measurement, it was found that the degree of crystallinity and size were not independent of the molecular weight and drawing ratio. By heat stretching of coagulated threads, highly orientated fiber is obtained easily in the case of low molecular weight. On the contrary, polymer chains of high molecular weight do not highly orient by the heat stretching at 100°C. For fibers having same orientation, tensile strength increases rapidly with the molecular weight. These phenomena are well explained by molecular theory.

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Copolymerizations of vinyl chloride (VC) with N-vinyl-carbazole (NVC), acenaphthylene (ANT) and glycidyl methacrylate (GMA) were carried out. The values of r₁ and r₂ were computed as follows.
VC (M₁), NVC (M₂); r₁=0.17 r₂=4.77
VC (M₁), ANT (M₂); r₁=0.001 r₂=64
VC (M₁), GMA (M₂);r₁=0.04 r₂=8.84
It was found that the softening points of the copolymers with NVC and ANT were higher than that of polyvinyl chloride. It was found that the component of the copolymer GMA retards the coloring of PVC by heating. The copolymer reacts with diamines, dicarboxylic acid and mineral acids to give crosslinked polymers.

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2-Methyl-5-vinylpyridine (I) was prepared from 2-methyl-5-acetyl pyridine (II), which was obtained by oxidation of 2-methyl-5-ethyl pyridine II was hydrogenated in 81-95% yield to 2-methyl-5-(α-hydroxyethyl) pyridine (III) with copper-chromite catalyst or was reduced with aluminum isopropoxide. III was converted to 2-methyl-5-(α-chloroethyl)-pyridine hydrochloride (IV) with thionyl chloride in 87% yield. IV was converted by trialkylamine to the corresponding quaternary ammonium salt (V), which, without isolation, gave I in 41-43% yield by heating with concentrated potassium hydroxide.

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