It is practically an important problem to measure the injection molding characteristics of resin using the minimum amount of the sample.A capillary tube flow tester was used to determine the melt flow properties, i.e., the apparent activation energy of viscous flow, the flow behavior index in the power law, and the shape of extrudates.The test was made for 9 kinds of resins.The flow properties of resins were compared with each other by the testing area diagram i.e., the diagram of temperature and pressure to get the flow rate at 10^-3-10^-2 cm³/sec with Koka type flow tester.The injection molding characteristics of polystyrene and high density polyethylene were estimated by the molding area diagrams obtained by a spiral cavity molding test, i.e., the test of the dependence of the spiral flow length on the cylinder temperature and the ram pressure.These data showed that polyethlene having greater apparent activation energy and flow behavior index showed greater cylinder-temperature and ram-pressure sensitivity than polyethylene. The testing area diagrams appeared to have certain analogy with the molding area diagrams.

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The polyvinyl alcohol film pretreated with water was irradiated in styrene with Co⁶⁰ γ-ray. Then the graft polymerization of styrene to polyvinyl alcohol film proceeded with the irradiation. The grafted film expanded almost evenly to the three dimensional directions.
Styrene grafted polyvinyl alcohol film was cut into small pieces. Using those many small test pieces, specific gravity, degree of swelling in water and benzene, heat plasticity etc. were measured.
It was found that there were little difference of properties between inner layer and surface layer of the film. The fact indicates that the graft copolymerization would proceed homogenously in the outer and inner parts of the film except extremely thick one.

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In this experiment, the irreversible thermal shrinkage of drawn polyethylene filaments are measured and their thermal expansion coefficients after the heat treatments as a function of temperature. When the degree of thermal shrinkage is plotted versus draw ratio, the maximum value of the irreversible shrinkage is observed at draw ratio 2. This suggests that in the highly drawn samples dimensional stabillization has occured at high temperature, during the drawing process, while in samples with lower draw ratio this stabillization is poor and has been attained in the cooling proccess. Dimensional changes of drawn polyethylene filaments after heat treatment depends on the molecular orientation.
Anomalously large coefficients of expansion were observed in the sample of draw ratio 1.5 and 2. This corresponds to a-axial orientation of crystallites which we observed by X-ray diffraction.

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Polypropylene was degraded thermally in vacuo and in air, and the changes in the degree of polymerization were studied. In the degradation in vacuo, the average number of links broken per molecule of the original polymer was proportional to the time of heating. So the scission of the main chain seems to occur at random. The apparent activation energy for the thermal degradation of the main chain was 51.4 kcal/mol. The rate of degradation in air was greater than that in vacuo.

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Solution polymerization of vinyl acetate was carried out in redox systems, one component of which was diisopropyl peroxydicarbonate (IPP) at 0°C to 40°C.
IPP-N, N′-dimethylaniline (DMA) system have very effective catalytic activity for vinyl acetate polymerization in methanol solution and the most effective mole ratio is [IPP]/[DMA]=1/1.The apparent activation energy of polymerization was 11.4 kcal/mol and the initial rate of polymerization (R_p) was proportional to the term of [IPP]1/2×[DMA]1/2.The system in methanol solution was slightly pink and the polymer obtained was slightly yellow, on the other hand, in bulk and in ethylacetate or benzene solution, the systems were colorless.
The polymerization using IPP only as a initiator was also examined and the apparent activation energy of polymerization was 18.5 kcal/mol and R_p was proportional to [IPP]1/2.

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The diffusion equation of spherical symmetry has been solved, and the pressure p in a hollow space of volume V is expressed as
where P is the permeability coefficient, D the diffusion coefficient, t the elapsed time, p₁ the gas pressure outside the sphere, r₂ and r₁ are respectively outer and inner radii of the sphere, l =r₂-r₁. P, D and the solubility coefficient of the highpolymer tubing and empty sphere have been calculated from the solution of these equation of cylindrical symmetry and the present solution. In the case of highpolymer membranes, such as cellulose acetate, cellulose nitrate and 6 nylon, the permeation rate of water vapor through them tends to give a steady state value after it passes a maximum value.

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The permeation and absorption of gases and vapor through polycarbonate film was examined. The results are as follows;(1) It is considered that the diffusion mechanism of a gas in unstretched and heat relaxed polycarbonate film is of the Fickian type, (2) The permeability and diffusion coefficient of gases and vapor decrease with the increase of molecular orientation caused by stretching.(3) The solubility coefficients calculated from equilibrium experiment are greater than those from permeation experiments in the case of stretched polycarbonate.This disagreement will be ascribed to a diffusion mechanism which is additional to the Fickian diffusion.(4) Carbon dioxide is dissolved comparatively readily in polymers which contain carbonyl groups.

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salt of glyoxylic acid-partial acetal of polyvinyl alcohol, containing about 6 mol% of carboxyl groups in the polymer chains. The osmotic coefficients calculated from the experimental data were found to be very small and to increase with the concentration of the polymer in solution. This result conforms with that previously found for linear copolymers composed of vinyl alcohol and acrylic acid units.
Further, in order to be able to discuss this result more fully, the degree of swelling of the crosslinked copolyelectrolytes composed of the same components as that of the linear polymer were measured in water. The osmotic coefficients evaluated from the results of the swelling equilibrium were compared with that for the linear copolymer.

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The acetone solutions of polymethylmethacrylate are viscometrically measured at temperatures ranging from 25 to 40°C by a Ubbelohde viscometer and the results obtained are compared with those of polystyrene in benzene. The intrinsic viscosity and the Huggins constant of polymethylmethacrylate show a maximum and a minimum at 30°C, respectively. The dependence of viscosity on temperature were able to be explained by taking account of the effects of solvation and flexibility of chains

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In the thermal properties of copolymers of vinyl chloride with other vinyl monomers, the effects of both chemical composition and monomers content on second order transition point were investigated. The flexural temperature and the flow properties of these copolymers were studied. These thermal properties were measured at higher chloride content region of copolymers than 40%. Effects of lower alkyl vinyl monomers, such as vinyl acetate, methyl acrylate and dibutyl maleate on these properties were little. Higher alkyl vinyl monomers, such as octyl acrylate, lauryl vinyl ether and vinyl stearate, and ethylenes monomer have so large effects (on the thermal properties) that some of these copolymers have lower second order transition point and flexural temperature than 30°C and superior flow properties.

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Three methods are given for estimating the parameters Km and a in the so-called Mark-Houwink equation
from measurement of single polymer-solvent system.The method 1; the parameters are calculated from intrinsic viscosity [η] and molecular weight M, the method 2; from [η], Mand second virial coefficient A₂, the method 3; from A₂ and M.These methods depend upon the theories which take account of the partly draining effect as well as the excluded volume effect.It is concluded that these methods are generally applicable for the practical purposes

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It has been well known that there was a simple relationship between intrinsic viscosity and a parameter expressing the dependence of the sedimentation constant on concentration for a number of vinyl polymers,
This relationship, however, could not be applied to the solution of cellulose derivatives and such fact has been quantitatively explained by taking into account the partly free draining effect on the hydrodynamic properties.The equation obtained from the consideration of the effect of free draining on solution properties indicates that the ratio ks/[η] increases with the increase of the draining parameter when X<1, and approaches to a constant value with the increase of X when X was larger than 1, and these results are in a good agreement with the experimental results reported in literatures.

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Viscosity characteristics of isotactic polystyrene were compared with those of atactic polystyrene taking account of a partly free draining effect on the intrinsic viscosity-molecular weight relationships.The results obtained were as follows.
1) A parameter Δ of isotactic polystyrene was larger than that of atactic one, where Δ was a parameter proposed in this paper as a measure of a free draining effect on an exponent a in Mark-Houwink equation.
2) A parameter (1/2-1-a₁) of isotactic polystyrene was less than that of atactic polystyrene, where (1/2+a₁) was a parameter proposed in this paper as a measure of an effect of volume exclusion.
3) The fact that the constants of the Mark-Houwink equation obtained for atactic polystyrene in good solvent was the same as that obtained for atactic polystyrene, which has been experimentally confirmed by many investigators, was explained taking account of the effects of free draining and volume exclusion the constants in the Mark-Houwink equation.
4) The difference in expansion factor a between isotactic and atactic polymer was due to that in thermodynamic parameter (Φ₁-k₁) as well as chain extension parameter (r₀²/M).
5) Various molecular constants of solution properties, for example those in the Mark-Houwink equation, were calculated from the theory proposed in this paper and they were compared with those in literatures.

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The molecular weight distribution after chain scissions was calculated for a polymer initially having a log-normal molecular weight distribution by the application of the idea of Sakurada and Okamura.If the molecular weight distribution of an original polymer is given by:
the molecular weight distribution of the polymer after chain scissions is given by:
where a is the probability of link breaking.nip is computed for different degrees of polymerisation and for various values of a.The correlation between the number of links broken and the ratio of the intrinsic viscosity before to after the chain scission is obtained by numerical integration with the aid of nip.

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A deuterated nylon 6 film was treated with a solution of iodine-potassium iodide in heavy water. The infrared spectrum of the deuterated nylon 6 was examined and compared with that of the undeuterated nylon 6 treated with iodine-potassium iodide aqueous solution.
The results confirmed conclusions of a previous paper.That is:(1) Iodine solution penetrates into the crystal lattice and a hydrogen bond between amide groups in the crystalline part is broken.(2) Behaviors of the 2460 and 2410 cm^-1 bands of deuterated nylon 6 are similar to those of the 3290 and 3070 cm^-1 bands of undeuterated nylon 6.(3) The amide characteristic bands of nylon 6 are as follows In the α-form, the bands at 1271 and 1202 cm^-1 are the amide III band and the 692 and 979 cm^-1 bands are the amide V and III' bands respectively. In the γ-form, the bands at 1274, 708 and 997 cm^-1 are the amide III, V and III'bands respectively.(4) In the γ-form, a coupling of the amide III band with a mode of hydrocarbon skeleton is smaller than in the α-form.(5) The absorption at 731 cm^-1 in the α-form and that at 728 cm^-1 in the γ-form are not the amide absorption but are ascribed to the CH₂ rocking vibration.

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The structural change in several polyamides due to the iodine treatment has been studied by x-ray diffraction and infrared absorption methods.Except nylon 610 and 11 all polyamides studied in this paper adsorb about 1 iodine atom per amide group.The x-ray diagram of the iodine-adsorbed nylon shows one strong ring which is due to the equatorial reflexion as that of the r-form of the polyamide does.With the removal of the adsorbed iodine, nylon 66 (the a-form), 57 and 59 (the r-form) revert to their original crystal forms, but nylon 6 (the a-form) and other polyamides with odd numbers of methylene groups such as nylon 56 and 65 (the γ-form) transform into the γ-form. On the α-γ or delta;-γ transition, the intensity of the band near 3070 cm-¹ which is a satellite band of the NH stretching band increases and the amide I and V bands shift to higher frequencies and the intensity of the band at 1180-1150 cm-1 increases in responce to the decrease in the intensity of the band near 1200 cm^-1. The position of the amide V band correlates closely to the crystal form.A discussion on the relation between the polymer structure and the transition is given.

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