Elastic moduli of crystalline regions parallel to the chaino-axis (E_t) were determined by an X-ray diffraction method for polyethylene terephthalate (PET) and its copolymer (PET/PEI), which contains8.3mol% of isophthalate as a third component. Both of them show almost the same crystalline X-ray diffraction pattern. E₁-values obtained are as follows:
PET: E_t=110×10⁴kg/cm² (21±1°C)
PET/PEI: E_t=115×10⁴kg/cm² (20±1°C)
The difference between these two values is within an experimental error of ±10%. This shows that E_t-value is not affected by the copolymerized component. Further the E_t-value observed for PET approximately agrees with that calculated by Treloar, i. e., 124×10⁴kg/cm².
We also measured the change of equatorial spacings of PET when the tensile stress was applied in the fiber axis direction. The spacing of the (110) plane decreased rather largely with stress, but the (100) plane showed almost no change. The change of the (010) plane lay between those of (110) and (100) planes and showed a complex behavior. The changes of spacings for these planes correspond to the crystal moduli in the direction perpendicular to the chain-axis.

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Elastic moduli of the crystalline regions perpendicular to the chain axis (E_t) were determined by an x-ray diffraction method for polyethylene terephthalate (PET) and its copolymers which constitute of 91.7mol%of polyethylene terephthalate and 8.3mol% of adipate (PET/PEA) or isophthalate (PET/PEI). E_t-values obtained are as follows:
PET…(100): E_t=4.7×10⁴kg/cm² (110): E_t=3.8×10⁴kg/cm² (010): E_t=4.2×10⁴kg/cm² (23±1°C)
PET/PEA…(100): E_t=4.7×10⁴kg/cm² (110): E_t=3.7×10⁴kg/cm² (010): E_t=4.2×10⁴kg/cm² (20±1°C)
PET/PEI…(100): E_t=4.2×10⁴kg/cm² (110): E_t=3.4×10⁴kg/cm² (010): E_t=3.8×10⁴kg/cm² (20±1°C)
The E_t-values of PET are nearly equal to those of polyethylene, which shows that no strong interchain forces work in PET. However, it seems that there exists a weak π-electron interaction between benzene rings, because the E_t-value for (100) plane to which the planes of benzene rings lie nearly parallel is somewhat higher than those for the other planes
When the E_t-values of PET and its copolymers are compared, the values for PET/PEA are almost the same as those for PET, but the values for PET/PEI are about10% smaller than those for PET in every direction. The cause of this decreasing seems to be that the isophthalate component can enter into the crystal lattice of PET more readily than the adipate component. Thus the disordered lattice gives lower E_t-values.

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Elastic moduli of the crystalline regions in the direction perpendicular to the chain axis (E_t) for the α-form of nylon 6 were determined by an X-ray diffraction method. The moduli observed were as follows:
Nylon 6 (α-form):(200)…E_t=7.3×10⁴kg/cm² (002)…E_t=4.4×10⁴kg/cm² (20±1°C)
The E_t-value for the (002) plane is nearly equal to that of polyethylene and the E_t-value for the (200) plane is much greater than that of the (002) plane. This result is in accordance with the crystal structure of the α-form of nylon 6, in which the direction of the hydrogen bonds are nearly parallel to normal of (200) plane.

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Mechanical denaturation of copoly (L-glu, L-ala) in aqueous solutions was qualitatively observed by applying various shearing forces. Coagulation of copoly (L-glu, L-ala)(19: 1) by shearing force occurred in aqueous solutions of a pH range from 3.8 to 4.5. The coagulated copoly (L-glu, L-ala) was proved to have the β-structure by IR and X-ray diffraction measurements. However, coagulated products of copoly (L-glu, L-ala)(9: 1) and copoly (L-glu, L-ala)(8: 2) caused by the shearing force had different structures and the transition into β-structure was incomplete. The coagulated copoly (L-glu, L-ala)(9: 1) caused by the shearing force had the β-structure with a small amount of α-helical structure, and the coagulated copoly (L-glu, L-ala)(8: 2) had a-helical structure. But, the precipitate from the aqueous solution of copoly (L-glu, L-ala)(8: 2) which had 80% helix content in the solution, was proved to have the α-helical structure with a small amount of β-structure.
The α→β transition takes place completely when the copolymer has low alanine content (19: 1), but it occurs partly in the case of other copolymers (9: 1 and 8: 2) with high alanine content.

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The amorphous poly (ethylene terephthalate) was crystallized at 115°C and 150°C. The spherulitic films were drawn at 110°C and 145°C, respectively. Deformation behavior of spherulites was discussed in terms of various small angle light scattering theories. Experimental results could not be explained by any of the theories, but constant volume hypothesis proved to be applicable in the initial drawing region. Internal structures of films were alsa, observed by X-ray diffraction, density, birefringence and stress-strain measurements. These results were explained by taking the deformation of spherulites into account.

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The dissociation constants (pK_b) of 2-substituted-4, 6-diamino-s-triazines (XT) and hydroxymethylated 2-methoxy and 2-isopropoxy-4, 6-diamino-s-triazines (MMT and MiPT, respectively) and methylolmelamines (MM) have been determined by electrometric titration.
The values showed that the basicity of 2-alkoxy or aryloxy (ROT), 2-alkylamino or arylamino (RNT) and 2-alkyl or aryl-4, 6-diamino-s-triazines (RT) became larger to some extent with an increase of carbon number in R (alkyl and aryl groups) except for phenyl group. It was found that in the case when R was the same group, the order of the basicity of ROT, RNT and RT was RNT>RT>ROT.
Hammett Relationship between pK_a (=pk_w-pK_b) of XT and the substituent constant σm was observed approximately. The following constants were calculated;the reaction constant ρ=4.28, pk_a (H)(X=H) =4.12, the coefficient of correlation γ=0.966 and the standard deviation _d=0.177.
In the hydroxymethylated amino-s-triazines, the basicity decreased with an increase of “n”(the average molar number of formaldehyde (F) combined). The dissociation constants of MMT, MiPT and MM having “n” below 3 were constant in the range of pH from ca. 6 to below the half neutralization point, but those of MM having “n” over 3 were not constant in the same range.
A linear correlation existed between pK_b and “n”, and the slope of the line for MMT was larger than that for MiPT.
The cause of the difference of the behavior between MMT and MM in the determination of pK_b's was discussed.

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Ionic crosslinking reaction was carried out in emulsion of styrene and methacrylic acid copolymers, using water soluble metallic salts. The results were as follows:
1) Only by dispersing free metallic cations in the carboxylic emulsions, ionic crosslinking reaction occurred.
2) Ion bond with Zn⁺⁺ was much stronger than that with Ca⁺⁺ or Na⁺⁺.
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 into the polymer.
5) Gel content of ionically crosslinked product was strongly influenced by [η] of the base polymer.
6) The degree of crosslinking increased with increasing diameter of emulsion particles of the polymer.
7) The degree of crosslinking increased as the pH of emulsion became alkaline.

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Relations between polymer structure and some physical properties for ionically crosslinked styrene-methacrylic acid (St-MAA) copolymers were studied and the results were as follows:
1) With increasing the density of crosslinking, the transition point of dynamic modulus (E') shifted to higher temperature and the value of dynamic shear modulus (G') at rubbery plateau increased.
2) The melt index values of ionically crosslinked St-MAA copolymers strongly depended on the degree of neutralization, and yet they were also related to MAA content and [η] of the base polymer.
3) St-MAA copolymers and its ionically crosslinked products had nearly the same value of activation energy for viscous flow.
4) The interionic force with Zn⁺⁺ was considerably strong and perfect melt flow was not observed even when temperature was elevated to 280°C
5) Ionically crosslinked St-MAA copolymers were easily molded by all the conventional thermoplastic techniques, by contorolling MAA content, [η] of the base polymer and the degree of neutralization.
6) The heat resisting properties of ionically crosslinked St-MAA copolymers were improved linearly with increasing MAA content.
7) Ionically crosslinked St-MAA copolymers had excellent boiling water resistance.
8) Remarkable effect of ionical crosslinking on the mechanical properties of St-MAA copolymers was not observed.

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In case of the ionic crosslinking reaction in emulsion state, there were some disadvantages such as the difficulty of coagulation or coloration of the polymers. These problems were solved by using styrene-mathacrylic acid copolymer polymerized in suspension polymerization.
Ionic crosslinking reaction occurred when the mixture of this copolymer and zinc acetate were extruded at 200-230°C. In this case, the crosslinking reaction and pelletizing of the polymer could be carried out at a time and the products were colored no longer.
No differences were observed in heat resistant or mechanical properties between the product crosslinked in emulsion state and that from suspension, but, in optical properties, the latter was more strongly hazy than the former. When methacrylic acid content became more than8%(wt), the environmental stress crazing began to appear.

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A copolymer of maleic anhydride with styrene and a copolymer of maleic anhydride with vinyl n-butyl ether were treated with ammonia in a mixture of toluene and', acetone. Acid anhydride groups reacted to give amide groups and carboxylic acid groups. By drying in vacuum at60°C, some of amide groups changed into imide groups and carboxylic acid groups. By hydrolysis with NaOH, a part of amide groups formed carboxylic acid groups. By hydrolysis with H₂SO₄, amide groups completely converted to carboxylic acid groups.
For the copolymerization of maleic anhydride with vinyl n-butyl ether in acetone at 50°C, the monomer reactivity ratios were found to be 0.045 (γ_m) and 0.00 (γ_v).

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The mechanism of bulk polymerization of methyl methacrylate (MMA) with acid clay was studied. The results obtained are as follows. 1) The rate of polymerization increased with the increasing amount of acid clay or water, and decreased with the elevation of the treatment temperature of acid clay. The apparent activation energy for the polymerization was 17.7kcal/mol. The polymerization was inhibited by the addition of diphenyl picryl hydrazyl. From these results, it was evident that the polymerization of methyl methacrylate with clay was initiated by the radical. 2) Taking consideration of our previous report that “MMA peroxides”(monomer peroxide and polyperoxide) are the radical sources which initiate the polymerization, we concluded that the acid clay accelerated the decomposition of “MMA peroxides” and consequently increased the rate of polymerization. 3) Although we could not exactly obtain the knowledge of the activation point of acid clay concerning with the accleration of the rate of polymerization, we made it clear that the lamella gap was concerned with the initiation of polymerization and served as the locus of polymerization.

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