The millings of polystyrene, polymethylmethacrylate, polyethylene, cellulose acetate and acrylnitrile-vinylchloride co-polymer were carried out with heating rolls, and the mechanical degradation of these polymers was studied. The degradation of polymer would be examined by measuring the viscosity of polymer solution. It was posturated that during mastication, C-C bonds, the back bone of polymer, were broken by the shearing force, resulting in the decrease of a chain length. No degradation appears to occure after the chain length is reached to a limitting length for a given polymer. It was found that the order in the rate of the mechanical degradation was polyvinylchloride, polystyrene, polymethylmethacrylate at our experimental condition.

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Vinyl polymers (Polyvinyl Chloride, Polystyrene, Polymethyl methacrylate and Polyethylene) are blended with rubbers (Natural rubber, NBR and SBR) using of roll in air. The blended material is again separated into two fractions by means of a good solvent (precipitant) for either rubber or vinyl polymer. It is to obtain a variation of the amounts of each fraction. Moreover, to find a mechanical degradation of vinyl polymer, the intrinsic viscosities of vinyl polymer are measured. It is now reported whether the vinyl chain is under goes scissions during the polymer-rubber blending on rolls.

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In this study, some thermoplastics were extruded from a simple die using a single screw extruder. Extrusion pressure and discharge rate were measured. From the results of the experiments, the flow constant k and n of the Ostwald's equation D=kτn were calculated. In the case of easy-flow plastics like polyethylene, values of several hundreds were obtained for k, while for n, they varied little in the range 2 to 3. On the other hands, plastics like the unplasticized PVC, had in general, very small k and relatively large n values. K increased approximately linearly and n reduced linearly with the increase of the extrusion temperature. They were each found to be a good measure for the mobility of polymers. Especially, for the unplasticized PVC, a compound having a good fluidity was found in the course of the study.

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Dependency of permeability coefficient (P) on film thickness was examined with the results as follows:(1) Measurement, made on the cup method for the permeation of vapor through high polymer film to which the vapor has affinity, indicated that P increased with increase in thickness of the film.(2) Residual solvent, residual strain and difference in structure of the inner and surface parts of the film, hitherto regarded as probable causes for the phenomenon mentioned in (1) above, were turned out to have little influence.(3) In the process of permeation, one side of the film is in “wet” condition and the other in “dry” condition. The proportion of the former increases with increasing the film thickness. This fact in the most probable cause for the increase in P with increase in the film thickness.

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From a practical standpoint, the fracture and the fatigue behaviour are examined on plasticized films by addition of m-cresol, di-ethyl phthalate, glycol monoacetate, ethyl phthalyl ethyl glycolate and tri-phenyl phosphate. The Boyer's equation on tensile strength holds on plasticized films added by m-cresol and di-ethyl phthalate. A plasticized film added by glycol monoacetate is tough on impact and static test. There are linear relationship between logalithm of elastic moduli and volume fractions of plasticizers. A high failure energy is observed on specimen added by mixture of tri-phenyl phosphate and di-ethyl phthalate at some mixture ratio. Impact strength increases with the use of tri-phenyl phosphate but static strength decreases. Both impact and static rupture energy increase with use of di-ethyl phthalate or ethyl phthalyl ethyl glycolate over 0.18 volume fraction. There is no definite relationship between elastic moduli and impact strength of plasticized films.

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The solvent power of methylene chloride-ethanol mixtures shows a maximum at 85%(by volume) of methylene chloride and that of chloroform-ethanol mixtures shows a maximum at 80% of chloroform, which is indicated by the parallel behaviour of [η], k′(minimum), dilution ratio, viscosity of concentrated solution (minimum), and activation energy (minimum). Toughness, impact rupture energy, fatigue property, tensile strength and ultimate elongation of films show a maximum and modulus of elasticity shows a minimum at the maximum solvent power. The salts effect is observed on solution viscosity and mechanical properties. The solvent power, toughness, and impact rupture energy decrease with polyvalent salts contained in cellulose triacetate.

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The change of molecular weight by heating was reported in the previous paper for polyamide. This phenomenon is treated kinetically for 6-nylon in this paper. Occurence of both polymerization and depolymerization seems to be the cause of this phenomenon. Both reactions are separated, using several experimental data, and change of number of molecules by polymerization is calculated against time. It becomes clear that this polymerization reaction is the second order for number of unreacted molecules and the activation energy of this reaction is computed as 12.7 kcal/mol form change of rate constant with temperature. Some suppositions, are made for mechanism of polymerization.

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Water adsorption of different heat-set nylon 6 fibre was measured in a range of 0-80%RH with a quarz balance and water of first layer (v_m) adsorbed was calculated by the BET equation. The value of v_m, was found largest for untreated fibre, medium for steam-set and smallest for dry-heat-set. The inner surface areas in nylon fibres calculated from v_m, were 4-5×10⁵cm²/g. It is supposed that the value obtained by deviding v_m by the amorphous fraction of heat-treated fibres relates to intermolecular bonds is a unit volume of the amorphous part. That the values thus obtained are smaller for the dry-heat-set fibres means that the amorphous region of the fibres contains more intermolecular bonds and consists of finer structure as compared with the untreated and the steam-set fibres.

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The dielectric properties of six kinds of vinylidene chloride and vinyl chloride copolymer (VC-VD copolymer) were studied over the wide range of frequency and temperature. For the sample I, II and III (Table 1), we observed one dispersion and for sample IV, V and VI, we saw two kinds of dispersion, of which the higher-frequency dispersion (β-dispersion) disappeared in the polymer containing vinylidene chloride more than 70%. The variation of the magnitude of dispersion which is related to the glass transition has been investigated, and we confirmed that the magnitude of dispersion was decreased with increasing the content of vinylidene chloride. From the dielectric point of view the glass transition temperature was lowered with increasing content of vinylidene chloride. The values of Cole's parameter a of vinylidene chloride and vinyl chloride copolymer decreased with increasing temperature and vinylidene chloride content. From the temperature dependence of dielectric dispersion, the activation energy for orientation of dipole in the sample I, II, III, IV, V and VI were calculated to be 34, 35, 40, 46, 64 and 92 kcal/mol, respectively, that is, the activation energy decreased with increasing the content of vinylidene chloride.

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The dielectric properties of polyvinylidene-vinylchloride copolymers (VD-VC copolymers), heat treated at 95, 130 and 145°C, were studied. In the case of VD-VC copolymer, we observed one dispersion. The degree of crystallinity was raised with increasing heat-treating temperature. The magnitude of the dielectric dispersion was decreased with increasing the degree of crystallinity. It may be concluded that the dispersion is due to the polar groups in the amorphous region. The value of Cole-Cole's parameter a of VD-VC copolymer was decreased with temperature and no change was observed by heat-treatment of the specimens.

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Thermal conductivity of three samples of low pressure polyethylene was measured in the range from -60° to +100°C. At about -20°C, conductivities of sample No.I (MW50000) and No.II (MW80000) begin to increase more depending to temperature. Above room temperature, the conductivity-temperature relations of sample No.I and No.II are similar to that of the high molecular weight polyethylene studied in the previous work, while sample No.III (MW120000) showed a quite different behavior. Values of thermal conductivities of three samples were higher than that of high pressure polyethylene. Effect of the change of the molecular weight or of the molecular configuration on the heat conduction in high polymers was discussed in qualitative terms.

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Thermal expansibility and temperature as well as humidity dependences of some viscoelastic properties of the following samples have been studied: secondary cellulose acetate (2AC), cellulose triacetate (3AC), cellulose nitrate (NC), ethylcellulose (EC), and benzylcellulose (BC). Contrary to results hitherto published, the secondary transition (β) is found to appear at about 45°C with insignificant variation for all the cellulose derivatives herein described. It is also found that EC, 2AC, and even NC show, due to moisture regain, a damping capacity comparable to the β transition at ordinary temperatures and humidities. In the case of usual unannealed AC films, another transition (α) is observed at 100-140°C besides the so-called internal fusion at 155°C for 3AC and at 185°C for 2AC. No temperature dispersion corresponding to the α-transition, however, is observed for well annealed specimens preheated at 190-200°C below the softening temperature which occures at about 185°C for 3AC and at 190-200°C for 2AC.

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Uniaxially-oriented specimens of polyvinyl chloride (PVC) show generally two new reflections, M₁ (d=5.15Å) and L₁ (d=4.69Å) on the meridian of the X-ray diagram. In order to decide a correct interpretation with regard to these reflections, we examined systematically many uniaxially-oriented specimens of PVC which had been prepared at the temperature range between 50°C and -78°C. The M₁ reflection can be explained as the meridian reflection which comes from the net planes perpendicular to the fiber axes in crystalline regions, and the L₁ reflection can be interpreted as the layer reflection. It seems that the intensity and the sharpness of these reflections increases according as the polymerization temperature decreases.

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The weight-average molecular weights of low-and high-polymerized dextrans, which were far from clinical ones, were observed by light-scattering method. The values M_w of weightaverage molecular weight of low polymerized dextrans were examined with that of numberaverage molecular weight M_n, calculated from an equation specified between intrinsic viscosity [γ₁] and M_n, which was given by Inoue. On the other hand, it has been confirmed that an enzym-synthesis method is a kind of useful means for producing considerably high-polymerized dextran, and an over-time fermentation of native dextran decreases inversely the molecular weight from its maximum value.

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Vinyl acetate is copolymerized at 50°C with higher alkyl (n-octyl-n-octadecyl) vinyl ethers in the presence of lauroyl peroxide as the initiator. Monomer reactivity ratios of vinyl acetate (M₁) and vinyl ether (M₂) are as follows:
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The rates of conversion and molecular weights of the copolymers decrease, as the fraction of vinyl ether increases in the monomer mixture. The fraction of vinyl ether in the copolymer increases with the increases of monomer conversion, while molecular weight of copolymer decreases.

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Acrylonitrile is copolymerized in bulk and in emulsion with higher alkyl (n-octyl-n-octadecyl) vinyl ethers at 50°C in the presence of benzoyl peroxide as the initiator. Monomer reactivity ratios of acrylonitrile (M₁) and vinyl ethyer (M₂) are as follows:.
As the content of the vinyl ether in the monomer mixture increases, tne rates of copolymerization and the reduced viscosities of copolymers obtained decrease, and states of copolymers change from rigid and unflexible form to soft and plastic one, and solubilities from insoluble to soluble in ordinary organic solvents other than dimethyl-formamide. Even though the alkyl chain length is varied from 8 to 18 carbon atoms, copolymerization rates of monomer mixture containing the same molar per cent of vinyl ether are nearly the same each other, and reduced viscosities, tensile strengthes and elongations of copolymers are slightly affected.

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p-Methoxystyrene was polymerized in methylene chloride, toluene and their mixed solvents with BF₃·O (C₂H₅) ₂ as catalyst at -20, -40, -60 and -78°C. As the polymerization temperature was lowered, the intrinsic viscosities of polymers obtained increased, and in methylene chloride the molecular weight of polymers was larger than those obtained in toluene at same temperatures. The precipitation temperature in acetone which indicates the solubility of polymer was dependent on the intrinsic viscosity. But polymers, obtained in methylene chloride of the same intrinsic viscosities, had precipitation temperatures 10°C higher than those in toluene, and the polymers from their mixed solvents had intermediate value. This, by comparison with polyvinyl alkyl ethers, probably indicates the difference in the stereoregularity of each polymer. But appreciable difference in properties of solid polymers-that is, specific gravity, X-ray diffraction pattern, infra-red spectrum and melting point-was not recognized.

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The synthesis of polyglucuronide from starch by oxidation with fuming nitric acid was studied. The best result for synthesis was obtained, when 50g of starch was reacted with 50-70cc of fuming nitric acid (sg 1.50) for 7-10 hours at 20-°25C. It was found that the oxidation degree of a product was about 90% and the yield was about 90% of the theoretical amount. These polyglucuronide products had nitrogen content of 0.5-0.6% and their intrinsic viscosity in 0.1N-NaOH solution was about 0.04.

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The copolymerizations of ternary system consisting of acrylonitrile, methylacrylate and 2-vinylpyridine were studied in aqueous medium by redox process using amonium persulfate and sodium bissulfite as catalysts. Good Agreement of the compositions was obtained between that calcutated from the “monomer reactivity ratios” each binary system through Q-e-scheme and that observed from the analysis of copolymers.

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Bulk polymerization of styrene was carried out in the presence of N, N′-dimethyl-N, N′-dinitrosoterephthalamide (NTA). NTA was a retarder in the polymerization catalyzed by α, α′-azobisisobutyronitrile. Chain transfer constants of NTA were evaluated from the polymerization degree of polystyrene, as 0.14 and 0.20 at 40 and 60°C respectively. It was also found that the thermal polymerizations at 80, 100, 110 and 115°C were first inhibited and then accelerated by NTA, as shown in Fig. 5.

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Polymerization of metacrylonitrile (MAN) induced by azobisisobutyronitrile (AIBN) was carried out at 60°C in benzene. Poly-MAN is insoluble in this solvent. The rate of polymerization was expressed by:R_p=const.[AIBN] ^0.75 [MAN] ^1.60. Formerly, in the heterogeneous polymerization of acrylonitrile, the following rate equation was proposed by Imoto and Takatsugi. R_p /[AIBN] =A′+B′/[AIBN] ^1/2. In this paper, it was ascertained that this rate equation was also applicable in the present case. The effect of co-existence of dimethylaniline in the above-mentioned polymerization was scarcely observed.

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