Relationships between limiting viscosity number and molecular weight for poly-(vinyl acetate)(PVAc) were determined from measurements of light scattering, osmotic pressure, end group determination and viscosity. Mostly the techniques employed was as same as mentioned in Part I and II. The range of molecular weight of the samples used was from 2×10⁴ to 120×10⁴ by weight average. From the data of light scattering and the measurement of end carbonyl group, the heterogeneity of the low conversion samples expressed by M_wM_n, was found to be 2 as expected by theory. The obtained relationships between limiting viscosity number [η] and molecular weights for unfractionated low conversion PVAc were renresented by the following eauations
in acetone:=
in methyl ethyl ketone: in methanol: in θ solvent, (a mixture of methyl isopropyl ketone 72.7vol % and n-heptane 27.3vol % at 30°C):
were M_w and M_n are weight and number average molecular weight, respectively, and [η] is represented in ml/g. The values obtained in acetone solution was corrected to the perfectly homogeneous specimens as follows: or, Where P is degree of polymerization.

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The influence of the degree of polymerization and its distribution upon the permeation of water vapor, nitrogen and carbondioxide through polymer films-polyethylene, polyvinyl chloride, ethylcellulose and polyisobutylene-has been studied. With lowering the degree of polymerization of polymer films, the permeability to gases and water vapor increases slightly and the mechanical property, however, decreases on the contrary. The increasing of the diffusion coefficient may be the most reason for the increasing of the permeability coefficient in that case. The author suggested that small channel, crack or flaws will be easily created in the polymer films by a little stress with lowring the degree of polymerization.

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Polyvinylalcohol fibers produced by wet spinning were subjected to heat treatment under tension at various temperatures between 120 and 230°C and eight kinds of samples were prepared. The meridional diffraction and equatorial scattering were measured with an Xray counter and it was found that the long-period spacing increased with increasing temperature from 126Å to 212Å and that the distance between crystallites, calculated with Kratky's equation of evaluation of equatorial scattering, increased from 83Å to 166Å.

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Two samples were chosen from those mentioned in Part 1. The temperature of the heat treatment were 220 and 230°C respectively. Small-angle scattering were measured in waterswollen state at room temperature. No change in the long-period spacing was observed but a remarkable increase in the diffraction intensity occured by these two samples.

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In order to examine a change in the small-angle scattering of polyvinyl alcohol fibres, with the degree of elongation, the unelongated fibres prepared by dry spinning were elongated to 2, 3, 4, 5 and 7 times of its original length. The measurement of the diffraction and scattering shows that both the long-period spacing and the distance between crystallites increase at the beginning but r increase is observed at higher degrees of elongation.

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Small-angle scattering was measured on the highly oriented material of various kinds of viscose rayons. For all of the materials used diffraction on the equator was hardly observed in the air-dried states but it appeared in the water-swollen states. In both states, however, no meridional diffraction to give a definite long period was observed.

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The object of the present report is to determine the behavior of molten polymer, which is assumed as Newtonian flow body in the previous work. Parallel plate plastometer was used and viscosities were measured under various conditions of temperature and pressure. The results were not so simple to justify the Newtonian behavior at once. The test pieces of resin were suffered more or less the thermal degradation, which depends on temperature and heating time. More over striking discrepancy on viscosity occured from the changes of preparation condition of test pieces. It was concluded that the melt viscosity was recognized as Newtonian, if the thermal degradation was not so appreciable. The thermal degradation was observed from the relation of melt viscosity and heating time and the relation of molecular weight and heating time. The mechanism of degradation should be the random fission of main chain of polymer molecule and not the preferential breaking of chain ends.

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A new chelate forming resin has been prepared starting from the chloromethylated polystyrene i) by the reaction of it with iminodiacetonitrile followed by acid hydrolysis of the product or ii) by the carboxymethylation of the aminomethylpolystyrene. This resin exhibited a characteristic affinity to metal ions. Although the 7.5% DVB cross-linked resin has exhibited no affinity to Fe²⁺, Fe³⁺, Ni²⁺ and Ba²⁺, its exchange capacities to Cu²⁺ and He²⁺ amounted to 0.8 and 2.9 meq/g, respectively, under the same conditions. The affinity of Cu²⁺ did change with pH so sensitive (max. at 5.1) that a limited degree of separation of this ion from Hg²⁺ was possible by an appropriate choice of pH in the column. Water soluble resin of the same type was obtained from the non-crossed polystyrene. The U. V. absorption spectrum was measured for the purified sample in the aqueous state and the 2:1 ratio of ligand (resin) to Cu²⁺ was determined by means of the method of continuous variation. This result and the titration curve suggested only the one carboxyl group of -N (CH₂COOH)₂ has been participated to form chelate with Cu²⁺. Preliminary examinations to prepare the resins containing -N(CH₂COOH)₂ group in their matrix of polyvinylalcohol and polymethacrylic acid were performed and the resulting resins had the exchange capacities to Cu²⁺ of 0.3 and 1.56 meq/g, respectively.

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γ-ray emulsion polymerizations of methyl methacrylate (MMA), vinyl acetate (VAc) and styrene (St) have been carried out. The rate and degree of polymerization with various emulsifying agents, i. e., cationic, non-ionic, and anionic, have been determined. The rate increases in the order of cationic<non-ionic<anionic and is 10 to 100 times larger than that of bulk polymerization carried out under similar experimental conditions. Experiments were also performed with different emulsifier concentrations, and the rate and degree of polymerization are recognized to be proportional to their concentrations. By substituting experimental values in the following equations proposed by Smith-Ewart, the exponent n₁, obtained from the rates and n₂ from polymerization degrees are in good agreement, lying within experimental errors, i. e. 0.14-0.40 where R_p is rate, P: degree of polymerization, C_s: concentration of emulsifier respectively

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The rate and equilibrium of ion exchange between anion exchange resins and an acidic dye, e. g., acid violet, are investigated. Results obtained are shown as follows;(a) log E is in the linear relation with log P, where E is the amount of ion exchange and P is the diameter of resin particle.(b) log E increases with the elapse of time, and this phenomena indicate ion exchange reaction in the resin phase.(c) The rate of ion exchange follows to the equation
E=ktⁿ where
E, t, k and n are amount of ion exchange, reaction time, and constants respectively.(d) The rate of ion exchange is influenced by the reaction temperature.(e) Amount of ion exchange of anion exchange resin with an acidic dye in alcoholic solution is very small.(f) Ion exchange equilibrium between ion exchange resin and acid violet is represented by Freundlich type of absorption isotherm.

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The causes of desulfonation in the course of sulfonated phenol-formaldehyde resin formation are investigated. Model experiments were examined by use of o-or p-phenol sulfonic acid, sulfonated phenol formaldehyde resin etc. with hydrochloric acid, acidic solution of formaldehyde or acidic solution of 2, 6-dimethylol p- cresol respectively. Consequently it was found that the desulfonation reaction took place by both (a) acid-catalysed hydrolysis and (b) cationoid substitution reaction by methylol cation (⁺CH₂OH) or different kinds of methylene cation (RCH₂⁺), and the latter reaction (b) is the main cause of the said desulfonation.

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The solubility and swelling in water of 1, 2-dihydroxyethylene modified polyvinyl alcohols synthesized by hydrolysis of vinylene carbonate-vinyl acetate copolymers have been measured. The solubility and swelling property became remarkable with the increase of 1, 2-dihydroxyethylene units in the modified polyvinyl alcohol chain. On the other hand, the curve of Huggin's k′ against mole per cent of 1, 2-dihydroxyethylene unit was observed to reach a peak, when it was near 20mol per cent. It was known from the measurement of infrared absorption spectrum of the modified polyvinyl alcohol that when more than a certain ratio of 1, 2-dihydroxyethylene unit is introduced the peak in the crystallization band of polyvinyl alcohol disappeared.

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In the cationic polymerization of styrene catalyzed by stannic chloride and boron fluorideetherate, the effects of addition of trichloroacetic acid, acetic acid and methyl alcohol were examined. According to the polymerization condition, the same additives accelerated or retarded the polymerization. This result could be interpreted kinetically by the fact that these additives had an effect on both initiation and termination reactions. There was a tendency that acidic additives became cocatalyst and basic additives became retarder, but they could be classified distinctly neither in cocatalyst nor in inhibitor.

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The carbon bisulfide does not copolymerize with vinyl chloride. In the polymerization of the vinyl chloride in the carbon bisulfide, the rate of polymerization is proportional to the square root of the initiator concentration, but a normal relation between the rate and the monomer, like in the butyl acetate or other medium which was reported previously, was not obtained. The degree of polymerization (P) drops conspicuously by the remarkable chaintransfer action of the carbon bisulfide. The relation between 1/P and CS₂/VC does not make a strate line. These peculiar results can be well explained by thinking that the system is not homogeneous, but the vinyl chloride monomer and the carbon bisulfide are mixed heterogeneously in the microscopic view. While, on comparison the polymer obtained in the bulk polymerization with that obtained in the carbon bisulfide solution by the infrared absorption, the existence of vinyl group at the end of the polymer was realized.

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The polymerization using sodium dialkyl phosphite as emulsifier was carried out in the sealed glass tube of 35 cc and in the stainless autoclave of 2 and 500l. And we discussed on the problem of the scale up. The necessary amounts of emulsifier are proportional to the surface area of the vessel contacted with a unit of solution in polymerization. That is to say, considering that the initiator was lost on the surface of the vessel, the less the surface area of the vessel, the more the effective micelles increase. Therefore, the necessary amounts of emulsifier are influenced by the sureface area of the vessel. The sealed glass tube of 35-150cc and the autoclave of 500ι are considered to be proper as the experimental step of scale up.

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Some polyoxazolidones were prepared by the polyaddition of aliphatic or aromatic diisocyanate with diepoxy compounds. The products obtained are almost insoluble in organic solvents, and decompose above ca. 280°C without fusion. This may be due to some crosslinking which is formed after the polyaddition. The decarboxylative cleavage of oxazolidone rings in the polymer by refluxing with phosphoric acid followed by an alkaline treatment yielded an anion exchange resin of polyimine type. For example, a brown hard resin, having the exchange capacity of 3.2meq/g, was obtained from the addition polymer of tetramethylene diisocyanate with hydroquinone diglycidyl ether.

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Bulk copolymerization of vinyl chloride with (I) diethyl itaconate, (II) diisopropyl itaconate and (III) dioctyl itaconate was studied at 50°C, using α, α′-azobisisobutylonitrile as initiator. The values of γ₁ and γ₂ which are monomer reactivity ratioes for each of these cases are (I)γ₁=0.06±0.01, γ₂=5.65±0.25, (II)γ₁=0.06±0.01, γ₂=6.0±0.5 and (III)γ₁=0.06±0.02, γ₂=7.0±1.0, respectively. Presence of a small fraction of dialkyl itaconates lowers the rate of polymerization of the system and decreases the viscosity of copolymers. From these results, it is concluded that changing alkyl group from methyl to octyl does not affect seriously the reactivity of the double bond of itaconate in the polymerization reaction.

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Bulk polymerization of dimethyl, diethyl, di-n-propyl, di-n-butyl and dioctyl itaconate was studied by dilatometry at 50°C, using α, α′-azobisisobutylonitrile as initiator. The rate of polymerization R_p is proportional to the square root of initiator concentration and k₀, in the equation R_p=k₀[M][I]^1/2, increases as the alkyl group changes from methyl to octyl. This fact is explained as follows. In the polymerization of itaconates, chain transfer of allylic hydrogen often occurs, producing rather stable radicals which delay the next propagation. Therefore, the higher alkyl itaconates should have larger k₀ if it can be considered that the higher becomes the alkyl group, the less becomes the chance of chain transfer because of steric hindrance of the alkyl group.

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Polyvinyl alcohol or its monochloroacetic ester was reacted in the mixtures of monochloroacetic acid and water in the presence of HCl. It was found that an equilibrium existed between esterification and saponification. The same type of the equilibrium relation as that for low molecular monofunctional compounds holds in this case also. The reaction proceeded according to a simple reversible bimolecular reaction scheme. The equilibrium constant and rate constant of the reaction were nearly equal to those for esterification of methanol with monochloroacetic acid. These results support the conclusion deduced in previous reports for the mechanism of saponification of polyvinyl acetate.

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To study the mechanism of saponification of polyvinyl acetate (PVAc) low molecular esters such as ethyleneglycol diacetate, 1, 2-and 1, 3-propyleneglycol diacetate, 1, 3-and 2, 3-butyleneglycol diacetate and triacetin were choosen as a model. Saponification rate of these compounds were meassured in water and acetone-water mixture (vol. ratio 75:25) in the presence of NaOH or HCl as catalyst. The appearent rate constant k changed a little in water, whereby a considerable increase with proceeding reaction was observed in the aceton-water mixture. The increase of k was greater for NaOH than HC1 catalyst, for esters in which the distance between two ester groups was shorter, and for secondary esters than primary ones. These behaviour were similar to that of PVAc. Based on these observations, a conclusion was drawn that the acceleration effect for saponification of PVAc was mainly due to catalyst adsorption by OH groups in the same molecule and partly due to decrease of steric hindrance. This conclusion is in accordance with that which was deduced in the previous papers.

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