Acrylonitrile was polymerized with radical initiators in dimethyl formamide, water or 60% aqueous solution of zinc chloride at 40-60°C. The obtained polymers were hydrolysed to polyacrylic acid (PAA), and titrated potentiometrically and conductometrically with sodium hydroxide or tetra-n-butyl ammonium hydroxide. The titration curves of the polymers were similar to those of PAA's derived from other various acrylic polymers prepared by radical polymerization; so that these polymers seem to have the similar steric configurations. PAA obtained by radical polymerization of acrylic acid in dilute aqueous solution of pH=7 was an exception, and showed remarkably different titration behaviours from the others.

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The single crystal of polyethylene oxide is near cubical form and its thickness is about 100 Å, the growth face is (120) plane. It is a tetragonal lamella with the molecular chain perpendicular to the lamellar surface. The radial direction of the spherulite is normal to the (120) plane if it has grown at the temperature higher than about 51°C, and to the (010) plane at the lower temperature. The radial growth rate also changes abruptly at about 51°C.

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Polyethylene terephthalate adipate (PET/PEA), polyethylene terephthalate sebacate (PET/PES), and polyethylene terephthalate isophthalate (PET/PEI) copolymers containing more than 90 mole-percent polyethylene terephthalate (PET) were prepared. The effect of foreign monomer units on the physical properties of these copolymers was discussed.
(a) Changes in T_m and T₀ of these copolymers show the best fit to Flory's and Gordon-Taylor's equations, which take into account of random copolymers.
(b) In copolyester fibers, the crystal of PET is unable to include foreign monomer units in it.
(c) The fibers scarcely contain voids of linear dimensions ranging from 20 to 300 Å, which voids would make X-ray diffraction patterns diffuse.
(d) For PET/PEA and PET/PES, with increasing proportion of the foreign monomer units, decreasing of crystallinity and increasing of dyeability are affected much greater than in the case of PET/PEI.
For PET/PES fibers, the shortening of a long period was also observed.
(e) In drawn fibers, reduction in the degree of orientation with copolymerization was generally observed while the degree of crystalline orientation was almost unaltered.

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Polyurethanes were prepared so as to get homologous series of polymers with respect to the concentration of polar groups and croslink density. Viscoelastic properties and glass transition phenomena were studied in the glass to rubber transition region.
Glass temperature is raised and the steepness of viscoelastic dispersion is decreased when the concentrations of urethane and biuret groups and the crosslink density are increased. In each case a large discrepancy was found to exist between the thermal expansion coefficient of specific volume and that of free volume derived by comparing WLF equation with Doolittle's equation in which the value of parameter B was assumed to be unity. As a possible way to account for this discrepancy, B is assumed to be a decreasing function of temperature supposing that the thermal dissociation of secondary linkages between polar groups may have an effect to reduce the size of elemental unit of molecular motion.

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An attempt has been made to measure the change in infrared absorption simultaneously with stress and strain for polymer films under straining. The usual double beam type in frared spectrometer has been modified in such a way as to allow one of the beams go through a specimen mounted on a stretcher. The stretcher is equipped with a load cell and an oven with a thermostat for temperature regulation, so we can record the stress on the specimen as well as the infrared absorption at a constant temperature up to about 150°C. The spectrometer has also been equipped with a quick return device for the motor in order to record the absorption in a rather narrow range of wave length repeatedly in a short time. This apparatus enables us to carry out various types of experiments including the following:(1) Measurement of the change in the intensity of infrared absorption at a given wave number during the stress relaxation and stress-strain measurements.(2) Repeated measurements of the change in infrared spectrum in a narrower range of wave number during the stress relaxation measurement as well as the stress-strain measurement at lower rates.(3) The above measurements can be carried out with unpolarized or polarized nradiation at temperatures ranging from room temperature to about 150°C.
The results of our preliminary experiment with low-density polyethylene films show that the shape of typical crystalline bands near 725cm^-1 and their maximum intensity (at 720 and 730cm^-1) with polarized radiation do not change with time during the stress relaxation measurement, though they could accurately be measured about one second after the initial stretching of the specimen.

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Physical properties of graft copolymers of acrylic ester on cellulose acetate were compared with those of the blended polymers of polyacrylic ester and cellulose acetate.
The following points are discussed in this paper.
(1) Tensile strength vs. tensile elongation and polymer dispersion
(2) Thermal behavior
(3) Temperature variation of dynamic viscoelasticity
Elongation of graft copolymers increases with increasing acrylic ester content while the elongation of blended polymers remains constant. Polarizing microscopic observation of films shows that graft copolymers have a better polymer dispersion. Increasing of acrylic ester content in graft copolymers results a decrease of softening temperature but the softening temperature of blended polymers keeps constant regardless of acrylic ester content.
Measurements of dynamic viscoelasticity demonstrate that both graft copolymer and blended polymer have two peaks at exactly the same location each corresponding to cellulose acetate and polyacrylic ester. However, E′ of graft copolymer is always lower than that of blended polymer.

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