Regarding the capillary flow of viscoelastic fluids, Philippoff et al. proposed the following formula:
P_corr=σ_CR (2L/a+2n+S_R)
In this equation S_R, the end correction term derived from elasticity of the sample, is the recoverable strain at the capillary wall (length L, radius a). However, it has not been clear whether S_R is truely equal to the recoverable strain or not.
In the present paper, S_R estimated from capillary flow was compared with the elastic recovery observed by a rotational viscometer type apparatus. The result shows that S_R estimated from both measurements is similar to the result by Philippoff et al. in the shear stress dependence, but is not identical.
It is considered that the rapid or abrupt increase of S_R values with shear stress in a capillary apparatus is caused by a thixotropic energy loss. This energy loss is estimated by comparison of the transient curves of shear stress-time preceding and following the steady flow in rotational viscometer type apparatus.

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The reaction between hydroxymethylated 2-methoxy-4, 6-diamino-s-triazine (MMT) and 2-methoxy-4, 6-diamino-s-triazine (MAT) in an acidic aqueous solution was studied kinetically assuming that reaction rates between each of the hydroxymethyl (methylol) groups in MMT and each of the amino groups of MAT are equal.
The reaction rates have been measured by employing both iodometric and ammoniumchloride methods at 25, 30, 35 and 40°C in an acidic aqueous solution containing 0.002000-0.0737mol/l of hydrochloric acid. The initial concentration of methylol groups of MMT (a) and that of amino groups of MAT (b) were 0.030-0.060 and 0.030-0.120mol/l respectively. The results are as follows:
1) The equation of the second order reaction consisted until ca. 0.0072-0.0090mol/l of methylol groups for each samples had been reacted.
2) The quantity of free formaldehyde (F) resulted from the dissociation reaction of MMT was approximately constant, for example it was ca. 9 % of the total methylol groups in the reaction of a, b=0.060mol/l at HCl concentration (AH) 0.0276mol/l, at 25°C, then its influence on the rate constant (k) was comparatively small, therefore it might be neglected.
3) The maximum value of k was obtained at certain concentration of acid, it for sample II was derived at the cencentration of added HCl 0.0295-0.0275mol/l (pH 2.75-2.85) in the reaction of a, b=0.060mol/l.
4) The k of MMT having small “n” (average molar number of F combined) was larger than that of larger “n”.
5) Activation energies (E) obtained here were 20.2-20.7kcal/mol, and approximately equal to E of reactions between MMT (n=1.66-3.01) and urea.

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Acrylonitrile (AN) was polymerized in the presence of polyvinyl alcohol (PVA) and a soluble PVA-AN graft copolymer was obtained.
The polymerizations were carried out in the following systems:
Ceric ammonium nitrate was used as an initiator, and a mixture of dimethylformamide (DMF) and water was used as a solvent.
Persulfates were used as an initiator, and dimethylsulfoxide (DMSO) was used as solvent. The graft copolymerizations in each system were investigated in detail and the following results were obtained.
a. 1) The fairly low grafting efficiency in DMF-H₂O solvent is probably because the considerable parts of initiation of grafting are caused by PVA radicals formed by the chain transfer of the growing polymer radicals, as well as by the direct reaction of Ce4+ with PVA.
2) With increase in the ratio of H₂O-DMF of the system, a maximum and a minimum rate of polymerization appeared.
3) When dimethylacetamide (DMA) and DMSO were used as solvents instead of DMF, the rate of polymerization increased in the order of DMA<DMF<DMSO, but the polymers obtained in DMSO-H₂O system were insoluble.
4) The effect of temperature on the polymerization were found to be similiar to that in the case of the typical redox polymerization.
b. 1) Among three kinds of initiators, i. e. benzoil peroxide (BPO), azobisisobutylonitrile (AIBN) and ammonium persulfate (APS), APS was the most active for the polymerization in DMSO of any of three monomers, i. e. AN, methylmethacrvlate, and the order of grafting activity of the sethree initiators was APS>BPO&cong; AIBN.
2) The rate of decomposition of APS in DMSO was much higher than in H₂O, and the overall activation energy of the polymerization of AN in the presence of PVA in DMSO was 14.0 kcal/mol.

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According to the conclusion of the preceding paper, we obtained the equation for the occurrence probability of each short chain branching structure and discussed about the dependence of its formation on polymerization conditions and compared it with the experimental data.
As the result, we obtained the following conclusions.
1) When the polymerizationte mperature is risen, or the polymerization pressure is decreased, number of ethyl branches/number of butyl branches (r), number of neighboring branches, total number of short chain branches, and number of ethyl branches seem to increase and the short chain branching structure seems to become more complicate. These branching parameters seem to remain constant by the addition of chain transfer agent.
2) In the case of the polymers which were produced at the same polymerization temperature, the more their total short chain branches or ethyl branches are, and in the case of the polymers who have the same number of total short chain branches or ethyl branches, the lower the polymerization temperature is, the larger their r value become. When we considered the data of each individual reporter, this prediction coincides with the experimental data.
3) From the experimental data on the short chain branching structure which was reported by other reporters, we calculated the difference between the energy of transition state formation in the case of butyl branch formation and that of in the case of ethyl branch formation as 2.5-5.4kcal/mole. This value is rather smaller than the value which were obtained in the preceding paper, but the relative relationship between the formation energy of the two transition states is unchanged in both calculations.

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Vinyl acetate-N-vinyl pyrrolidone copolymers (VAc-VP) were hydrolyzed with polymeric sulfonic acids such as polystyrenesulfonic acid or low molecular sulfonic acids such as dodecylbenzene sulfonic acid, and the rate constants (k_s) of the hydrolyses were compared with those of hydrolysis carried out under same condition using hydrochloric acid as a catalyst (k_HCl). Ratios of the rate constants, r=k_s/k_HCl for the hydrolysis, which were generally greater than unity, were even greater than those for the hydrolysis of partially acetylated polyvinyl alcohols (Ac-PVA). Effects of acetyl content of the substrates, the structure of sulfonic acids and reaction mediums on r-value were less remarkable in the hydrolysis of VAc-VP than in the case of the hydrolysis of Ac-PVA. These results may be due to a greater binding tendency of VAc-VP in comparison with Ac-PVA to such sulfonic acids. The r-values of hydrolysis of allyl acetate-N-vinyl pyrrolidone copolymer (AAc-VP) were somewhat greater than those of hydrolysis of VAc-VP.

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