In order to obtain the flow characteristics of polymer in melt state which are important in practical processing, we prepared a capillary rheometer. The rheometer is a screw extruder equipped with an overflow valve and direct detectors of pressure and temperature of melts.
The flow properties of Staflen E605 (a grade of high density polyethylene) measured here showed to have two discontinuous regions. On the melt fracture region, a sudden increase of apparent fluidity was found, from which the existence of slip flow at the capillary wall was observed.

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X-ray diffraction method was applied to investigate the change in the crystal state of polyamide 6 with drawing.
The width and length of crystal, which were estimated from the half value width of the (100) diffraction on the equator, and from the small angle diffraction on the meridian, respectively, both decreased monotonously with the draw ratio, except for the samples drawn immediately after spinning.
A sharp increase in the crystalline orientation has been observed in the range of low draw ratio; this increase was more remarkable in case of less crystalline samples.
The degree of amorphous orientation was calculated from the crystalline orientation, birefringence and density of sample.
The amorphous orientation increased less sharply in the range of low draw ratio than the crystalline orientation, but it still increased gradually in the range of high draw ratio where the crystalline orientation no more increased.

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Several samples of polypropylene were fractionated by stepwise extraction with a series of solvents at their boiling points. The structural heterogeneity was estimated with the stereoreglarity parameter and the viscosity average molecular weight of the fractions. A correlation was obtained between these two quantities with the most of fractions except for those of low regularity. The tacticity of the intermediate fractions increased with their molecular weights, while that with high tacticity showed no dependence on the molecular weight. Though this relation in the intermediate part varied from sample to sample, it appeared to be related to their over-all regularities. The distributions of stereoregularity of the all samples polymerized with three component-catalyst system containing EtAlCl₂ were found to be sharp.
Furthurmore, the results of the column fractional solution method at a constant temperature support the above conclusion, giving the information about the efficiency of the fractionation by solvent extraction.

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The TiCl₃ (AA)-(C₂H₅) _nAlCl_8-n (n=3, 2, 1.5) catalysts was heated at 95-155°C before polymerization and compared the activity of polymerization for propylene. Before heat treatment the activity of the catalysts was in the order of (C₂H₅) ₃Al>(C₂H₅) ₂AlCl>(C₂H₅) _1.5AlCl_1.5 for aluminium components. After heat treatment at 95C° and for 60min, activity of TiCl₃-(C₂H₅) ₂AlCl and TiCl₃-(C₂H₄) _1.5AlCl_1.5 systems reached 2.3 and 3.8 times of the activity of untreated catalysts respectively, whereas TiCl₃-(C₂H₅) ₃Al system decreased the activity. During heat treatment, total concentration of alkylaluminium compounds in solution did not changed substantially, but ethyl groups of alkylaluminium compounds was gradually replaced by chlorine atoms. These results are explained by alkylation reaction of TiCl₃ followed by reduction to TiCl₂. The active species are suggested to be the complex of alkyltitaniumchlorides with alkylaluminium compounds.

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In the bulk polymerization of methyl vinyl ketone, the Arrehenius plot within the range from 0°C to +60°C showed a straight line, and the activation energy was calculated to be 6.4kcal/mol. A study on the effects of solvents and inhibitor on the polymerization at-78°C has shown that the polymerization proceeded by a free radical mechanism. From the relative rate of polymerization in acetone with respect to the rate in bulk at 0°C, the G-value of free radical production for the monomer was calculated to be 0.52 times of that for acetone. On the other hand, a strong sensitizing effect of the solvent was observed in the polymerization at-78°C in the same system. In the polymerization in bulk or in acetone, intrinsic viscosity of the polymer increased with conversion and polymer insoluble in acetone, which was considered to be a crosslinked polymer, was formed. In the polymerization in methylenechloride, a colored polymer, which was seemed to be an intermolecular aldol condensated polymer, was formed.

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Radiation induced copolymerization of styrene and methylmethacrylate in the presence of γ-alumina was carried out at low temperature.
The influence of calcinating temperature of γ-alumina on copolymerization reaction was investigated.
From the composition of copolymer obtained, it was found that radical mechanism took place at 30°C and 0°C, but anionic one at -78°C.
In addition, in the case of γ-alumina calcinated at the temperature higher than 900°C, copolymerization was not observed, because of transformation to α-alumina.
Silica oxide, zinc oxide and nickel oxide were not effective on this system. It was supposed the absorption of monomer on the surface of γ-alumina played an imortant role.

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Polymethyl acrylates prepared by radical polymerization of acrylic acid, methyl acrylate, tetrahydrofurfuryl acrylate and acrylic anhydride were saponified in a acetone-water mixture (7: 3 by volume) using NaOH as a catalyst. Polymethyl acrylate, which differed markedly from the others in potentiometric titration behaviors and seemed to be more syndiotactic, showed a much higher initial rate of saponification (about 20 times) than the others, and th apparent rate constant of the sample decreased with conversion contrary to those of the othe samples. Methyl acrylate polymers prepared by radical polymerization at various composition of polymerization mixtures and temperatures showed nearly the same reaction rate to each other; therefore it seems that they have nearly the same steric configuration. Some discussions were given for the results.

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It was found that popcorn polymer was produced in aqueous acrylamide solution under the irradiation of gamma-rays and that the growth of popcorn seeds in various monomer was also increased by the irradiation.
A seed in a mixture of two kinds of monomer grew a popcorn co-polymer. The popcorn obtained had always some characteristic infrared absorption spectra at 1730, 1650 and 750cm^-1, being independent of the polymer component, and these spectra could not be seen in the general corresponding homopolymers.
ESR spectra of the irradiated popcorn were also quite different from those of the correspoding homopolymers.

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Oxygen-absorption data obtained for polypropylene samples with different specific surface areas were used to estimate the values of approximate safe limit of specific surface areas for oxidation.
The oxygen-absorption rate was calculated from the slope of the linear portion of the oxygen-absorption curve. Provided that each value of the specific surface area of the samples is larger than that of the safe limits, the oxygen-absorption should be occurred uniformally all over the samples.
The relation between specific surface areas, S (cm²/g) and absolute temperature, T (°K) was shown as follows._??_
This equation is useful to calculate approximate safe dimensions of specifically shaped samples. For example, the safe thickness of the films is calculated to be 0.23-0.09mm at 99-128.5°C.

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From oxygen-absorption curves obtained for polypropylene under various reduced pressure of oxygen, the relations among induction period [P (min)], oxygen-absorption rates [K_R (cc/g·hr)], oxygen-pressure [p (atm)] and absolute temperature [T (°K)] were studied at 110-129°C.
The oxygen-absorption rate was calculated from the slope of the linear portion of the oxygen-absorption curve, and the length of the induction period was obtained from the extrapolation of the linear portion to the time axis.
Following experimental equations were obtained._??_

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Crystalline polyether was obtained when acetaldehyde was polymerized with n-butyl lithium as catalyst. Effects of various polymerization conditions on polymer yield and crystallinity of polymer were studied. Polymer yield was the highest when ethyl ether was used as solvent and the highest crystallinity of polymer was obtained when n-hexane was used as solvent at -100°C. Polymers were fractionated by acetone and chloroform and viscosities of soluble part in each solvent were measured. Mechanism of the polymerization was discussed from the obtained experimental results.

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Polymerization of acetaldehyde with alkali metal-aromatic hydrocarbon complexes as catalyst was studied. Lithium, sodium and potassium were used as alkali metals and naphthalene and anthracene were used as aromatic hydrocarbons. Low polymer yield and low crystallinity of polymer were obtained when polymerization was carried out at -78°C with any of these complex catalyst. However, both yield and cyrstallinity of polymer increased when polymerization temperature was reduced to -100°C. Polymerization depended upon the sort of alkali metal, but was independent of the sort of aromatic hydrocarbon. Generally, high polymer yield was obtained when polar solvent was used and crystallinity of polymer was the lowest when tetrahydrofuran was used as solvent. High crystalline polymer was obtained in relatively high yield when ethylether or toluene was used as solvent.
Refering with the solubility in acetone and chloroform with infrared spectrum of the polymer, it was observed that the ratio of optical density at 8.4μ and 9.6μ could semi-quantitatively represent the crystallinity of the polymer.

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Block copolymerization of acetaldehyde was attempted by addition of acetaldehyde into the solution of living polymers at low temperature. Living polymers of styrene, α-methyl styrene, 2-methyl-5-vinylpyridine, methylmethacrylate, isoprene and butadiene were prepared with catalyst containing alkali metal such as alkali metal-aromatic complexes and n-butyl lithium.
Acetaldehyde could be polymerized by any of living polymers in toluene at -100°C and polymer, which principal ingredient was crystalline polyacetaldehyde, was obtained. It was confirmed from the measurement of infrared spectrum of the polymer that block copolymer of both components has been prepared. These block copolymer were thermally more stable than homopolymer of acetaldehyde.

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Polymerization of n-, iso-bytyraldehyde and chloral with sodium naphthalene complex as catalyst was studied. Polymers were obtained in relatively high yield when these aldehydes were polymerized at -78°C. Tendency of reducing polymer yield with increasing polarity of solvent was observed in the polymerization of n-butyraldehyde but the highest polymer yield was obtained when iso-butyraldehyde or chloral was polymerized in ethyl ether as solvent. Polymers of n-and iso-butyraldehyde were crystalline and independent of the sort of a solvent used in the polymerization.
It was confirmed from the measurement of infrared spectra that block copolymers of both these aldehydes and styrene or 2-methyl-5-vinylpyridine were obtained by using living polymer. Both homopolymers and block copolymers of these aledhydes were partly soluble in chloroform and their thermal stability varied with the aldehyde.

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