The structures of many kinds of PVA and their structural changes following colorisation at heat treatment were investigated by ultraviolet absorption spectra. PVA prepared by ordinary method more or less have absorption bands near 230 mμ, 280 mμ and 330 mμ and the intensity was increased strongly by heat treatment. It was considered the absorption bands near 230 mμ, 280 mμ and 330 mμ were those of K-band corresponding to, -C=C-C=O-, -(C=C) ₂-C-and-(C=C) ₃-C=O-respectively, which were further identified by using chemical method. It was thus concluded that-C=O-and-(C=C) _n-C=O-groups consist originaly very little in the PVA chain and induce the growing and increasing themselves at the occation of heat

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Shear dependces of the viscosity of the polyvinylalcohol (PVA) solution were studied for the moderate concentrated solutions at 30°C.:(1) Inthe low shear region, the plots of the reduced viscosity, η_sp/c, vs. the shear rate, γ, are horizontal and the solutions seem to be Newtonian. This region decreases with increasing of the concentration and the molecular weight of PVA.(2) The limiting shear rate, γ_cril, under which the solutions can be regarded as Newtonian, is obtained for the various concentration and molecular weight. In the dilute solution, e. g. 0.5 g/100 cc, the solutions can be regarded as Newtonian under 400 sec^-1 unless the molecular weight of PVA is very high.(3) The shear effect, -d (η_sp/c)/dγ, increases with the concentration and the molecular weight of PVA. The relations between the shear effect and the concentration are linear but the slope increases sharply at Ccrit, which is proportional to 1/[η] of PVA. This Ccrit is equal to the critical concentration, which was found in the study of the concentration dependences of the viscosity, η, and the apparent activation energy of flow, Eη, for the PVA water solutions.

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The shear effects, -d (η_sp/c)/dγ, on the viscosity of the polyvinylalcohol (PVA) solution, were studied in the shear rate ranges of 300-1300 sec-1 for the moderate concentrated solutions at 30°C:(1) The shear effect increases with the molecular weight, and this increment is particularly remarkable in the high molecular weight regions.(2) The influence, on the shear effect, by the difference of the molecular weight distribution of PVA, can be negligible if molecular weight is shown by the viscosity average.(3) The shear effect rapidly decreases by introducing the different groups such as acetyl groups or carbonyl groups in the chain of PVA.(4) The shear effect on the partial acetylated PVA is smaller than the partial saponified polyvinylacetate at equal acetyl%. This seems to be caused by the difference of the distribution of the acetyl groups along the chain.(5) The shear effect is especially re markable in the case of using water as solvent compared with other solvents such as dimethylsulfoxide (DMSO), water-DMSO, and water-n-propylalcohol. These results (from (3) to (5)) can be explained based on the considerations of the intra-molecular hydrogen bonds of PVA in the soluions.

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A X-Ray diffraction apparatus was constructed, in which polymer specimen could be kept at any temperature between room temperature and 400°C, and the diffraction intensity could be measured by using a X-ray counter. Poly (vinyl alcohol), (PVA), as a typical crystalline polymer, was chosen for the present study and the behaviour in the wide angle diffraction at high temperatures was investigated. The crystal lattice of PVA-fibres which have been heat-treated is expanded on heating from room temperature to 210°C. For example the spacing of (100) increases from 7.80 to 8.04A on heating. The crystalline diffraction intensity remains constant between room temperature and 180°C and is somewhat decreased at 210°C. For the samples which have not been heat-treated, the effect of the heat-treatment i.e. the contraction of the lattice is supperposed upon that of the thermal expansion. The crystalline diffraction intensity increases on heating from temperature to 200°C. PVA on heating upto 230°C gives a liquid diagram. Although samples, which have been heated up to 270°C, gives the typical crystalline X-ray diagram of PVA on cooling down to room temperature, samples heated above 290°C gives only an amorphous diagram when cooled to room temperature. However in the latter, appreciable chemical changes such as oxydation and thermal decomposition might have taken place on heating process.

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Small angle scattering intensity of poly (vinyl alcohol) was measured at high temperatures in order to obtain a knowledge of the long period in the direction of fibre axis, and was interpreted by the theory proposed by K. Hess and H. Kiessig. When heat-treated PVA fibres are heated under tension, keeping a constant length, the long period of 212Å at room temperature remains unchanged up to 225°C. Meanwhile the small angle scattering intensity increases. This is the case also for the heating without tension. For the fibres which have never been heat-treated, the long period increases from 111Å to 147Å on heating from room temperature to 225°C under tention and a remarkable increase in small angle scattering intensity is observed. The effect of heating on the long period and small angle scattering intensity is not so remarkable if no tension is applied during the heating process. In all cases, by cooling from a high temperature the long period does not vary whereas the intensity is lowered.

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The infrared spectra of PVA model, PVA and copolymer of vinyl alcohol have been investigated at about 9μ region to obtain some informations on the crystallization-sensitive band at 8.7μ of PVA. Then, the following facts were observed:(1) in PVA model, namely heptanetriol-2, 4, 6 and pentanediol-2, 4, the analogous bands to the crystallization-sensitive band of PVA appeared at nearly the same position, (2) the analogous band locations did not almost shift on deutration, just like PVA (3) the existence of crystallization-sensitive band even for the PVA whose polymerization degree was several tens, (4) no observations of crystallization-sensitive band for concentrated aqueous solutions of PVA and their gels. From such observations and data by another authors, it may be infered that the crystallization band will be associated with the coupling mode between C-C vibration of trans conformation and C-O vibration in that which formed intramolecular hydrogen bond in the crystalline region. It was also discussed about the assignment for another bands at 9p region of PVA.

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Three kinds of sample of polyvinyl alcohol in water were studied by the light scattering method. The weight average molecular weights (M_ω) determined by the dissymetry method in centrifuged solutions at 23000 g were found to be about two times the viscometric molecular weights. It was shown, however, that the dissymetry coefficient (Z₄₅)'s and the molecular dimensions seemed to be too large, compared with the values of molecular weight thus obtained. The Zimm-plots of these solutions were found to be unusually distorted. And the values of Mw and radii of gyration evaluated from these plots were absurd. These behaviors show that in the solution there exists considerable quantity of microgels. When solutions was filtered with “Membrane Filter” while heating, scattering intensity was decreased remarkably, nevertheless the value of intensity at θ=30° was still too large. The filtered solution was stored in a refrigerator for two weeks and then heated at 100°C. By this treatment, it was observed that it occurs the increase of scattering intensity, compared with the original solution. This behavior was also observed, even though the measurements were carried out at 82-87°C after storage at room temperature. By these results, it is suggested that the microgels in the solution are the aggregated particles of polyvinyl alcohol molecule that can not disperse completely even at above 80°C, and that at room temperature these particles could cluster as the gel particles which are visible.

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The specific volume-temperature curves were determined dillato metrically for various samples of hexamethylene-isocinchomeronamide copolymer from room temperature to melting temperature. The melting point vs composition curve has a minimum ; the gradual introduction of isocinchomeronamide produces a despress in melting point until about the 3/7 composition, but beyond the 3/7 the melting point rises, in spite of the possibility for isomorphism of the isocinchomeronyl and adipyl groups in copolymers. The heat of fusion, 10600 cal/mol calculated for polyhexamethylene adipamide from Flory's equation agree with the value calculated from Dole's equation. This is considered to depend on the isomerism be based on the position of the nitrogen atom in pyridine ring. The melting temperature range is similar to the value from specific heat method and shows a maximum at about 50 mol% isocinchomeronamide, but the change of specific volume in that range shows a minimum at same composition.

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Viscosity of the solution of poly-(trifluorochloroethylene) in o-chlorobenzotrifluoride was determined at 110, 120 and 130°C. Three samples of the polymer were used. They were powder of Fluorothene FYTD, FYTH and FYTS. Viscosity was determined by Ubbelohde viscometer. The concentration of the solution was determined by the weighing method, in which the viscometer was weighed after measurement, since appreciable quantity of the solvent evaporated during the dissolution of sample and measurement. Several error sources of this method were considered, checked and discussed, being compared with the dilution method. The results were shown in Fig. 3, 4, and Table 1. The temperature dependence was not appreciable, and κ of Huggins' equation is 0.85, equal for all three samples.

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The viscosity measurements were performed with poly (vinyl alcohol) partially acetalized with glyoxylic acid in solutions of a simple electrolyte and Pals-Hermans' method of dilution was applied. It was found that the extension of a macro-ion on the dilution line was kept constant over a polymer concentration range covered, utilizing our treatment previously reported. A parameter, m, in this method of dilution was known not to be far from the ratio of activity coefficients of polymeric and simple electrolytes. From these considerations, the “effective ionic strength” proposed by Pals-Hermans was suggested to be a significant quantity in dilute solutions of polyelectrolytes.

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In order to obtain informations concerning submicrostructure of polyethylene terephthalate (PETP) fibers, the sorption isotherms of undrawn and drawn fibers heat-treated at various temperatures were obtaind, by measuring the amounts of phenol adsorbed by the fibers from the aqueous solutions of phenol. Mechanical properties are also measured in the phenol solutions in the corresponding concentration range. The results obtained may be summerized as follows: 1) the sorption isotherms support the view that such variations in the degree of internal geometrical order as in cellulosic fibers occur in the amorphous and low order regions of PETP fibers (The high order regions could not be studied by this sorption experiment). 2) In undrawn fibers, crystallization occurs above 100°C and the crystallites grow into more perfect ones with increasing temperature. 3) Even in drawn fibers, crystallization does not occur until the temperature exceeds 100°C, although the stretch faciliates the transformation from the low order to the higher order regions. 4) The stress-strain curves of undrawn monofilaments show a great deal of yield in the phenol solutions, and the “yield” stress decreases rapidly with the increasing concentration of phenol. 5) The drawn monofilaments begin to exhibit remarkable shrinkage when they are immersed in the phenol solutions having the concentrations above 4.5%(or 5.1% for the samples heat-treated at 95°C). This critical concentration just corresponds to a transition point in the sorption isotherm, above which the amount of phenol adsorbed rapidly increases.

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Several types of cellulosic rayons have been investigated by means of acid hydrolysis combined with alkali swelling and chromic acid oxidation, in order to obtain further quantitative informations regarding the fine structure of regenerated cellulose fibers. The alkali swelling results in increase of the leveling-off DP and elongation of crystalline particles obtained by the subsequent hydrolysis, probably due to molecular rearrangement which has occurred in intercrystalline regions, while the yield of hydrolysis residue remains almost unaltered. The chromic acid preoxidation gives rise to decreases of both the leveling-off DP and the residue yield, apparently due to effective prevention of the recrystallization, which would otherwise take place during hydrolysis. It is highly probable that the oxidation of cellulose of intermediate order proceeds not only in a form of end attack, but also of lateral attack toward the crystalline regions, since the hydrolysis crystallites obtained are revealed under electron microscope as much more finely dispersed particles than the usual hydrolytic residues. Serious experimental difficulties are frequently encountered on the filtration of those residues owing to the peptization of the particles, rendering the measurement data less reliable. The extent of this peptization, however, may be an index of structural features inherent to each kind of regenerated cellulose fibers.

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Poly (vinyl alcohol)(PVA) is degradated oxidatively in aqueous solution by potassium permanganate (KMnO₄). 4 KMnO₄ molecules are consumed for every cleavage of the bond in the main chain. The ends of each degradated PVA molecule are consisted of about 1.5 carboxyl group and 0.5 carbonyl group. Further there exist about 2-3 carbonyl groups per each molecule as side groups. All the oxygen atoms of consumed KMnO₄ seem to be used for the formation of these groups.

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With the object of assuring that an abstraction reaction of hydrogen atom from polyvinyl acetate (PVAc) by radicals from BPO may yield a ketonic carbonyl group in the main chain, the reaction between PVAc and BPO was studied by the method previously reported to determine the carbonyl content in the main chain of polyvinyl alcohol (PVA). When enough BPO was used, the increase of the carbonyl content in the main chain of the PVA was confirmed, but the radical efficiency to yield the carbonyl group was less than 1%. In the quantity of BPO actually used, the formation of the carbonyl group in the main chain was small and negligible. When AZN was used instead of BPO, the carbonyl group was not found.

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Benzylchloride condenses slowly to dimer or trimer by heating without catalysts. The mechanisms, especially the positions of condensation have been investigated using both the deuterium tracer technique and the infrared absorption method. The reaction occurs at the benzene ring ca. 40% and the rest at the side chain. The relatives of three positions of the ring are 1.0, 0.26 and 0.18 for para, ortho and metha, respectively. No evidence is found for isotopic effect on the condensation at the benzene ring. The cathionoide mechanisms are proposed.

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In the agitated emulsion polymerization of methyl methacrylate containing DBP, the rate of conversion decreased with increasing amount of DBP. The rate of transfer of DBP into polymer particle increased as the emulsifier concentration and initiator concentration increased. The amount of DBP did not affect the number of polymer particles. These phenomena were discussed theoretically.

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In the emulsion polymerization of methyl methacrylate containing DBP in both layer system (non-agitated) and agitated system, the rate of conversion was higher than the rate. of transfer of DBP into polymer particle, and the difference of these rates decreased with increase in emulsifier concentration and decrease in initiator concentration. In the layer system (non-agitated), the ratio of the monomer conversion rate to DBP transfer rate was proportional to the ratio of methyl methacrylate to DBP in oil phase.

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The graft copolymerization of styrene on polymethylmethacrylate was carried out at 60, 70 and 80°C using benzoyl peroxide, lauroyl peroxide and a, a′-azobisisobutyronitrile as initiater. The grafting efficiencies were compared in each cases.

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The bulk polymerization of acrylic esters by γ-rays of Co⁶⁰ source is investigated here with the dose rate of 9200 r/hr at 40±1°C, and G values are calculated from the rates of initiation. G values of methylacrylate, ethylacrylate and n-butylacrylate are found to be 7.0, 10.9 and 17.4 respectively. G values of propionic esters and acetic esters are measured by DPPH-scavanging method and the influence of the length of their side chains are studied on the rates of radical formation. G values are recognized to be in the following order Me<Et<n-But, and may be related to the number of C-H bonds in their ester groups.

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New polyamides having thiophene nucleus were prepared by the polycondensation reaction of thiophene-2, 5-di-β-propionic acid with polymethylene diamines of carbon number of 4 to 10. All of the polyamides obtained here, except one derived from tetramethylene-diamine, showed good melt-spinning property and gave cold-drawable filament. The effects of thiophene nucleus inserted in polyamide chain on melting point and thermal-stability were discussed.

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