The additivity-law on the molar-volume of liquid is applied to polymers. The molar-volume of the construction-unit is computed for about 50 polymers from their density data at roomtemperature. These values for molar-volumes are compared with the additional values of atomic volume of liquid at boiling-point.The mean value of the ratio of these two volumes is 72.6±2% on the whole, 74.2±2% for the amorphous polymers and 68.5±2%;for the crystalline polymers.The value 74.2% for the amorphous polymers closely agrees with that for supercooled liquid at second-order transition temperature.As the transition temperature for the amorphous polymers dealed here is about 35°C on the average, it is concluded that the transition point is the corresponding state among polymers and liquids.The atomic volumes for amorphous polymer at transition point (or roughly at room temperature) being about 3/4 of those for liquid at boiling point, are postulated as follows. C=10 (8 for ring-construction), H=3, 0=8(6 for C=0, 5 for OH and 9 for acid), N=9, F=7, Cl=16, Br=20, S=17, CN=22 and Si 24.Adjusting value:-for-CH₂-CH₂-CH₂-and+8 respectively for-CH₃ and-C₆H₅ both combined to main-chain.

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The influence of temperature on the intrinsic viscosity and Huggins' slope constant k′ of dilute solution containning 0.5-10 gr polyacrylonitrile per 1, 000cc dimethylformamide were studied by the ostwald-type capillary viscometer at 10-100°. The temperature at which the degradation of polymer chain by the disslution takes place lies in 50°C to 60°C. The intrinsic viscosity-temperature relationship was found to be
log [η] =logA+B′/T, B′=299
The constant k′ of the Huggins equation was not found to vary greatly at temperature studied (30°C-70°C).

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The influence of temperature (30-70°C) and concentration (4-20%) on the Viscosity of concentratad dimethylformamide solution of polyacrylonitrile (D=545, 1400, 3250) was studied by the falling ball method.The results are summerized as follows.
1) Relative viscosity can be calculated by
ηrel=(1+ac) ^k, k=11
2) The viscosity-temperature relationship was found to be
logη(poise)=logA+B′/T
where B′ varies from 800 to 1600 as to the degree of polymerization, and since the activation energy varies between 3, 000 and 7, 000 cal.

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Representative several kinds of unsaturated polyesters were synthesized and the dielectric properties of their cured copolymers, obtained by varying molecular structures, unsaturation degrees and cross-linker styrene contents, were measured in the frequency range of 30-10⁶ cycle per second and at the temperature range of -60°C-120°C. Simultaneously, results on the resistivities, hardnesses, heat distorsion temperatures and swelling properties, were obtained and discussed.As polyester chains, containing polar groups, are cross-linked by styrene, the changes of their dielectric losses are more complicated than those of other polymers.Excepting the conduction loss appears in the lower frequency and higher temperature region, two kinds of dielectric dispersion are recognized.The dispersion in the low temperature region was almost independent on the species of polyester in its value and appeared in the same frequency range, and had small activation entropy value.So it was concluded that the dispersion above mentioned was resulted from the orientation of the small polar groups (probably -OH end groups).The dispersion in the higher temperature region is resulted from the orientation of the larger segment, and so the distribution of the relaxation times is broadened and its frequency characteristics has no distinct maximum of dielectric loss.When the saturated dibasic acid content in polyester is increased and the segment length between cross-links becomes larger, the “high temperature loss ”becomes higher generally.The changes of heat distorsion, swelling property etc, resulted by the polyester composition, show nearly equal tendencies stated above.

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Twenty-seven years ago, from the view-point of covalent bond theory, K. H. Meyer and H. Mark proposed a molecular model for crystalline part of silk fibroin from Bombix mori, in which glycine and L-alanine are arranged alternately. Since then, many workers have attempted to establish the structure from a number of experimental approches. It has, however, been unsuccessful to obtain any synthetic macro-polypeptide in which two different amino acid residues are arranged alternately along the polymer chain, and, therefore, confirmation of the Meyer-Mark's model for silk fibroin through the synthesis of the model has not been achieved. The employment of our N-carbothiophenyl method has now been possible to eliminate these difficulties.We have been able to prepare several such macro-polypeptides, including the Meyer-Mark's model itself, and compare them with the natural product by infrared absorption method and X-ray diffraction analysis. From the above results, we can conclude that our poly-glycyl-L-alanine, regular macro-polypeptide in which glycine and L-alanine residues are arranged alternately, is in best agreement with the crystalline part of Bombix mori silk protein.

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