Non-sensitized graft polymerization of styrene to nylon 6 fiber was carried out by using a mutual irradiation technique, with the light of wavelength longer than 300mμ. In the absence of solvent, the grafting little proceeded except in the cases of an irradiation temperature above 60°C or the “regrafting”. At 25°C, only methanol in various solvents showed a remarkable accelerative effect on the grafting, and maximum effect occured at about 30vol% of monomer. Ethanol, n-propanol and n-butanol also accelerated the grafting to the extent of methanol, with rising irradiation temperature or adding water to alcohol solution, but then the greater the carbon number of alcohol, the higher temperature or the larger quantity of water were necessary. When carbon tetrachloride was added to methanol solution, the grafting was extremely retarded. From these results, it was found that alcohols were not indispensable to initiation reaction of the grafting, but necessary to penetration of monomer into the inner regions of nylon 6. And further, alcohols had also the “gel effect” and the effect on the light absorption of monomer and nylon 6.
In the case of styrene-methanol (3: 7), Arrhenius plot of the rate of grafting versus 1/T exhibited a break at about 25°C. The overall activation energy of the reaction was 1.2 kcal/mol above 25°C.

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Mixtures of acrylonitrile (AN) and methyl acrylate (MA) were grafted onto polyvinyl alcohol (PVA) in aqueous solution using ceric ammonium nitrate. The resulting latexes had excellent film-forming ability. The films prepared from the above latexes on at 20°had unique physical properties which are different from those of films prepared from vinyl-polymer latexes.
The electron micrographs of the graft copolymer latex films, on which the contours of individual particles were discerned, show that the latex film consists of two phases, a dispersed phase (AN-MA copolymer component) and a continuous phase (PVA component).
The mechanical properties of the graft copolymer latex film (Young's modulus, tensile strength, elongation at break, impact strength, folding endurance, and heat-resistance) vary with MA content in AN-MA copolymer, and are affected both by heating the film at 105° for 10min and by the treatment of the latex with ion-exchangers. The graft copolymer latexes where the ratio of AN-MA copolymer (60-80 wt % MA) to PVA were 3 produced transparent films having 4-6kg/mm2 tensile strength, 5-50% elongation at break, good folding endurance, and excellent heat- and water-resistance.
The above results are illustrated in terms of the physical properties of PVA (continuous phase) and AN-MA copolymer (dispersed phase).

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Emulsion polymerization of vinyl acetate was carried out with hydrogen peroxide-glyoxal, and the resulted polyvinyl acetate was hydrolyzed to polyvinyl alcohol. The quantitative determination of 1, 2-glycol of the polyvinyl alcohol was made by periodate-arsenious acid method, and the results suggest the existence of about three moles of glyoxal residues per polymer molecule. Moreover, the periodate oxidation of the polyvinyl acetate polymerized with hydrogen peroxide-glyoxal resulted in the decrease of the degree of polymerization, and the treatment with tert-butyl hydroperoxide or tolylene disisocyanate increased the intrinsic viscosities of the polyvinyl acetate. On the other hand, these phenomena were not observed on the polyvinyl acetate obtained by the usual emulsion polymerization initiated with hydrogen peroxide.

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The effect of hydrogen chloride on the thermal decomposition of polyvinyl chloride in powder or in solution was studied. Ultraviolet and visible absorption spectra, carbon-carbon double bond contents and intrinsic viscosities of decomposed polyvinyl chloride as well as loss in hydrogen chloride were measured for determination of pyrolytic change in structure. On the basis of these data, it was confirmed that hydrogen chloride promoted the thermal decomposition of polyvinyl chloride. Furthermore, in consideration of behaviour of hydrogen chloride to decomposed polyvinyl chloride, it was suggested that hydrogen chloride reacted principally upon unsaturated structures, carbon-carbon double bonds, in polyvinyl chloride as a catalyst of isomerization, ionic dehydrochlorination and polymerization and as a reagent for addition.

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β-(Acryloyloxy)-propionamide (β-APAm) was prepared using β-propiolactone as a starting material. Two kinds of the propagation step were determined in the anionic polymerization of this monomer, that is, a so called hydrogen transfer (H-Type) polymerization and vinyl (V-Type) polymerization, which were estimated by IR spectra of the polymers. It was found that both H-and V-Type propagation took place with t-BuOK in 0-dichlorobenzene, while only V-Type polymer was formed in dimethylformamide, toluene and chlorobenzene. Poly (β-APAm) polymerized with t-BuOK in o-dichlorobenzene was soluble in dimethyl sulfoxide, partly soluble in formic acid and insoluble in other usual solvents, while poly (β-APAm) initiated with potassium persulfate in water was soluble in water, methanol and insoluble in other usual solvents.
Poly (β-APAm) and poly acrylamide (poly (AAm)) were hydrolyzed with 6N hydrochloric acid and their hydrolyzates were allowed to react with 2, 4-dinitrofluorobenzene. The products were analyzed by UV spectroscopy to determine the quantity of amino-nitrogen in β-amino acids, which were resulted from the sequences formed by H-Type propagation. The degree of H-Type propagation in the polymerization was determined by the (amino-N)/(total-N) ratio in the hydrolysis products of the polymer.
The ratio of the optical density of amide II band (1550cm^-1) to that of amide I band (1670cm^-1) in IR spectrum showed a good correlation with the degree of H-Type propagation determined by the (amino-N)/(total-N) ratio described above. Poly (β-APAm) initiated with t-BuOK in 0-dichlorobenzene had 35% H-Type content at most, while poly (AAm) had 66%. The results indicate that the polymerization of β-APAm proceeded mainly by the intermolecular proton transfer mechanism.

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The elementary reactions of isoprene polymerization intiated with polymethylenedilithiums Li (CH2) _n Li such as n=4, 5, 6, and 10 and with n-butyllithium have been studied in diethylether solution.
In the case of Li (CH₂) ₅Li, Li (CH₂) ₆Li, Li (CH₂) ₁₀Li and n-butyllithium-initiated polymerization, the concentration of lithium attached to the polymer end (polymer-end-Li)[P_t] reaches immediately to the concentration of charged initiator-end-Li. The absence of termination, chain transfer and association reaction of [P_t] is confirmed. The rate constant of propagation reaction k_p is obtained as 1.27 (l/mol·min).
In the case of Li (CH₂) ₄Li-initiated polymerization, a sigmoidal conversion curve and slow increase of [P_t] is observed. The rate constant of initiation reaction ki is determined from the relation between charged initiator concentration [C] ₀ and [P_t] which is expressed by the following equation,
_??_
where τ is a variable defined as τ=∫[M] dt. This equation gives the rate constant k_i as 3.73×10^-3 (l/mo·min). The propagation rate constant kp is obtained as 1.15 (l/mol·min) from the following equation.
_??_
This k_p value agrees well with those of other initiator systems.
The calculated molecular weight distribution based on these rate constants agree well with that determined by the column fractionation method.

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Recrystallization of quenched thin film of isotactic polypropylene during annealing at temperatures between 155°C and 168°C for different time has extensively been studied by observing density, infra-md spectra, electron micrograph, specific heat and melting temperature on the annealed film and the film quenched after annealing. Electron micrographs of the annealed film shod that recrystallization during annealing was at least in part, accompanied by the thicke-ning of lamellae. Two melting peaks were observed in thermogram of dfferential scanning caldrimetry of the film quenched after annealing. Lower melting peak which resulted from melting of crystallites of the original quenched film or melting of crystallites crystallizeo in cooling process after annealing shifted to lower temperature and area under peaks which was proportional to crystallinity decreased with increase of time of annealing. Higher melting peak which was due to melting of crystallites crystallized at annealing temperature shifted to higher temperature and the area under the peak increased with increase of time of annealing. Both thermogram which was taken on the annealed film by heating from the annealing temperature after annealing and the change in density with time at annealing temperature suggest that recrystallization takes place at the annealing temperature after rapid partial melting. Since observed melting temperature can be expressed as a function of heat of fusion ΔH and anneaing time t i.e., T_m (t, ΔH), the equilibrium melting temperature T_m 0 is defined as lim t→∞ΔH→∞ T_m (t, ΔH) =T_m (∞, 0). Following the method described above, the value of T_m⁰ was estimated as 186. 5°C for whole polymer having viscosity-average molecular weight of 1.93×105. Some experimental basis for the so-called sliding diffusion theory have been discussed in detail. It also becomes evident that lower, small peak in thermogram characteristic of the annealing temperature between 70°C and 150°C (ref. K. Kamide et al: J. Chem.High Polymers, Japan, 24, 662 (1967)) and multiple peaks corresponding to the supperposed annealing process can reasonably be interpretd in terms of partial melting followed by recrystallization resulting in thicker lamellae.

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The mechanical denaturation of poly-L-glutamic acid (PGA) in 0.2M NaCl aqueous solutions and in 0.2M NaCl-dioxane (2: 1, by volume) aqueous solutions by shearing force was studied. The coagulation phenomena of PGA in the above-mentioned solutions caused by the shearing force were different from those in the aqueous solutions reported before.
The viscosity and optical rotatory dispersion were measured to clarify the conformation change of PGA in these mixed solvents.
The process of the mechanical denaturation of PGA in these solutions can be assumed that the α-helical conformation with helix content 70% or more changes itself into the β-structure by means of the shearing force.

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The effect of the velocity of increase in the shear rate (γ) on the critical shear rate (γ_c), the shear rate at the coagulation, of an aqueous solution of higher syndiotacticity poly (vinyl alcohol)(PVA) was studied. The PVA derived from poly (vinyl trifluoroacetate) was used. The degree of polymerization and the percentage of syndiotactic diads of the PVA were 7700 and 55.1%.
In the case of the same polymer concentration, γ_c, decreased with the decrease of γ.
When the polymer concentrations and γ's were varied so that they might give a certain value of γ_c, the polymer concentrations decreased at first with the decrease of γ but gradually reached a certain value respectively (for instance γ_c=3000 sec^-1, polymer concentration≈2.45%). The shear stress at γ_c increased with the increase of γ.

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In order to find a general rule in the “hardness” of polymeric foam substances in which the closed cells are dispersed randomly, local compression tests within the range of elastic limits were carried out on the artifiial double-structured foam substances containing relatively large cells perforated in the commercially available isolated foams. Experiments show that the dent profile can be expressed by the surface of revolution of exponential curve around the indenter. The depth of dent is proportional to the load on the indenter. Since this depth depends on the radius of indenter, it can not be used as the measure of the “hardness”. The dent volume is, on the other hand, independent on the radius of indenter and depends only on the load. This proportionality constant is a local compressibility and can reasonably be used as the measure of “hardness”. Experiments show that the local compressibility k_p of general foam substances can be expressed as:
_??_
where _km denotes the local compressibility of polymer which is matrix component of the foam, p the volume fraction of matrix, and βa constant which is independent on the kinds of polymer and depends on the structural factors such as shape and size and their distributions of cells in the foam.

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Viscoelastic and thermal behaviors of polyvinyl chloride (PVC) films prepared in different conditions were studied near the glass transition temperature (T_g). PVC films (degree of polymerization 800-1400) cooled slowly under pressing from melt to room temperature show two transitions at 58°C and 71°C in differential scanning calorimetry (DSC). Filmsprepared in the same way but having higher degree of polymerization (2200-2700) show only one transition. By the heat treatment at higher temperatures than T_g, the low temperature transition disappears and the high temperature transition shifts to the lower temperature.
Films cast from tetrahydrofuran solution show also two transitions at 55°C and 77°C. The low temperature peak in DSC of the solvent casting films is larger than that of melt pressing films. The peak of dynamic loss E'' corresponds to larger peak of DSC. So the viscoelasticity of PVCs prepared in different conditions shows the quite different behaviors.
PVC films swollen in various organic solvents and dried, were studied. Though the polymer is not crosslinked, the structures during swelling are fairly kept in solid state and its viscoelasticity is different from that of untreated or crosslinked polymer. The shapes and positions of two transitions in DSC changes according to the solvents used. It is suspected that bulkiness and entanglement of chain affect these behaviors.
PVC-styrene graft copolymer was prepared by Co⁶⁰ γ-ray irradiation and its properties were also examined. By the grafting and swelling during polymerization, PVC-styrene copolymer shows a complicated transition and it is separated into two components by the heat treatment.
These results suggest that the low temperature transition in DSC is due to the mobile short chain or bulky region made by the swelling or the grafting and entanglement of whole chain causes the large unusual endothermic peak of the transition.

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1) As a first step to make clear the polymer-solvent interaction parameter μ of a binary copolymer in relation to those of the parent homopolymers, the chemical composition dependence of the cohesive energy density has been deduced by using quasi-chemical method. The cohesive energy density δ2 of the copolymer is found to be
_??_
(1) where β is the volume fraction of the constituent A in the copolymer and λ is such an arbitrary constant as to represent the relative strength of the A-B contact pair and λ=0 and λ=4 correspond to the perfectly miscible and completely incompatible cases of both constituent elements, respectively.
2) To take account of the restraining effects of a copolymer chain which enchains both constituent elements in a same molecule, it has been assumed that the ratio of the A, B contact pairs in solution remains near the same value as before dissolution through the intramolecular entanglements of copolymer chain which remain partly in solution. The interaction parameter kt of the copolymer is found to be:
_??_
(2) where α represents the fraction of the A, B contact pairs in which restraints imposed by the entanglements are operative.
3) Eqs.(1) and (2) were proved to hold by the experimental data obtained from swelling measurents of seven kinds of butadiene-acrylonitrile rubbers different in chemical composition.

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