Measurements of the intensity of polarized laser Raman scattering have been used to investigate the distribution of orientations of the structural units (molecular segments or crystallites) of an oriented solid polymer. In this paper, the orientation of polymeric chain is evaluated more quantitatively on the basis of the fundamental relation between Raman scattering intensity and molecular orientation in anisotropic solids of polymer. This evaluation is performed by expanding the addition theorem of generalized Legendre's function. Improvements over previous works include the following: 1) Effects of birefringence are taken into account in the evaluation by separating two effects: one occurs before the interaction of incident light with the chemical bond in a molecular chain and the other appears in the scattered light. 2) The anisotropy of the scattering intensity about the axis normal to the surface of the sample film is considered. The influence of birefringence is connected with the molecular orientation to make the quantitative evaluation more reasonable. 3) The intensity of Raman scattering of oriented polyethylene film is evaluated through the calculation of the polarizability tensor of each chemical species of a chain.

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A method to control the fine pores in high molecular weight polyethylene (PE) films from its mixture with liquid paraffin (Pa) by rolling compression has been examined. The mixtures with various ratios were hot rolled, and then PE was extracted in organic solvent. The fine structure of these films was investigated via measurements of the apparent specific volume, the surface area using the after N₂ gas adsorption-desorption method, and the small angle X-rays. PE films of the mixing ratios (C) from 0.10 to 0.50 at rolling ratio of 6 to 30 times at 115°C have layer-like pores. Specially wide surface area, 170m²/g, was achieved by rolling the films having C=0.17 to 0.10 at rolling ratios of 20 to 30. Stacking with pores decreased the thickness with increasing rolling ratio, i. e., down to 60 to 200Å. The form of pores was probably layer-like: longer in the rolling direction and shorter in the width direction.

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The superdrawn structure of gel processed films of ultrahigh molecular weight polyethylene was studied by these methods: differential scanning calorimetry (DSC) in relation to the elastic property, the morphology after melting, and the wide angle X-ray diffraction at high temperature. Two kinds of endothermic peaks were observed, around 153°C and above 160°C, in the DSC curves of fixed-end films. The lower temperature peak includes the heat of fusion of orthorhombic crystallites and the heat of transition from the orthorhombic to hexagonal phases. The higher temperature peak corresponds to the melt of hexagonal parts. By separating the heat of fusion of the orthorhombic phase, the ratio of the transition part to total crystalline part was estimated to be 2.3 times the ratio of the area of higher temperature peak to the total area of the lower and the higher temperature peaks. The transition from orthorhombic to hexagonal phases occurs in crystallites whose pulled-out chains are constrained by entanglements generated in the drawing process. This constraint is partly released by destruction of entangled chains as the draw ratio increases.

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Annealing effect on chemical structure and physical properties of thin films, prepared by r. f. glow discharge of triethylindium (TEI), was investigated. The film, as deposited, contained mostly hydrocarbon, and the appearance was dark brown and opaque. The structure of the film was amorphous. On annealing in air, hydrocarbon contents in the film decreased, oxygen contents increased, and the crystallization progressed. The appearance of the film changed from opaque to transparent, and the electrical conductivity increased by annealing. The conductivity of the film after annealing, which was determined by a hot probe method, was of n-type, and the activation energy was calculated to be about 0.07 eV from the temperature dependence of the conductivity.

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To prepare the polymer-grafted carbon black with a higher percentage of grafting, radical graft polymerizations of vinyl monomers onto grafted polymer chains on carbon black surfaces were investigated. During the polymerizations of vinyl monomers with benzoyl peroxide as an initiator in the presence of alt-copoly (styrene oxide/maleic anhydride) or alt-copoly (glycidyl methacrylate/phthalic anhydride) -grafted carbon black, these vinyl polymers are found to graft onto the unsaturated polyester on carbon black. The percentage of grafting of vinyl polymer onto carbon black increased with an increase of total conversion; the percentage of grafting of poly (methyl methacrylate), polystyrene, and poly (vinyl acetate) onto alt-copoly (styrene oxide/maleic anhydride) -grafted carbon black increased up to about 500%, 110%, and 95%, respectively. The effects of structure of unsaturated polyesters and initiator on the grafting of vinyl polymers onto unsaturated polyester-grafted carbon black were investigated. The polymer-grafted carbon black with a higher percentage of grafting could be dispersed easily in various polymers. Furthermore, the tensile strength of polystyrene films compounded with the polystyrene-grafted carbon black with a higher percentage of grafting was compared with that of untreated carbon black.

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Bulk-copolymerization of substituted allyl esters of tetrabromophthalic acid [1] and diallyl phthalate (DAP) in the presence of benzoyl peroxide as a radical initiator has been studied in order to obtain optical resins with high refractive indices. Effects of the composition and polymerization conditions on the refractive indices, densities, hardness and residual unsaturation of the copolymers were investigated. The refractive indices and densities increased almost proportionally with the content of [1] in the copolymers prepared under adequately heated polymerization conditions. Under milder polymerization conditions, however, the relation between the physical properties (refractive index and density) and the content of [1] deviated from the linear relationship and their plots at the 20-30 mol% content region of [1]. One reason for these phenomena is that addition of [1] promotes the polymerization in the copolymer system. This promotive effect is interpreted as a change, in the stability of the π-complex between polymerizing radicals and aromatic rings, which is caused by-I effect of Br substituent.

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Thermostats were constructed for light scattering at high temperatures up to 200°C. The intensity and line width of scattered light were measured for polystyrene solutions in cyclopentane near the lower critical solution point. The measurements for the same system near the upper critical solution point were performed for comparison. The values of critical exponents γ and ν were found to be γ_U=1.16 and γ_U=0.59 for the upper side, and γ_L=1.15 and ν_L=0.58 for the lower side. The dependences of line width on the temperature and wave number on the lower side were almost the same as those on the upper side. These facts imply that the lower critical solution phenomena of polymer solutions belong to the class of critical phenomena specified by the space dimension d=3 and the number of components of order parameter n=1; this is also true for the upper critical solution phenomena.

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Carbon cloth-reinforced epoxy resin composites were irradiated with 2 MeV electrons at room temperature and then annealed in air for 2 h at temperatures up to 180°C. A considerable decrease in the three-point bending strength occurred when the irradiated composites were annealed in the temperature range of 115-135°C which is below the glass, transition temperature T_g, of the matrix resin, while the bending strength remained unchanged up to 180°C for the unirradiated composites. In the dynamic viscoelastic spectra of the irradiated matrix, a new relaxation appeared at the temperature extending from 50°C to just below the matrix T_g, and disappeared on annealing for 2 h at 135°C. Annealing also decreased the concentration of free radicals existing stably in the irradiated matrix at room temperature. After annealing, a large amount of clacks and voids were observed in the fractography of the composites by scanning electron microscopy. These results indicate: (1) Annealing brings about rearrangement of the radiation-induced molecular chain scission in the matrix; (2) The bending strength of the irradiated composites decreased owing to the increased brittleness of the matrix by annealing.

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Poly (propargyl methacrylate) was synthesized by the reaction of poly (methacrylic acid) and propargyl bromide using DBU in DMSO. The reaction proceeded quantitatively at room temperature within 10 minutes. Photochemical properties of the resulting polymer were measured by IR spectroscopy and practical photosensitivitiy with several photosensitizers or photogenerated cationic catalysts as crosslinking reagents. The polymer showed the highest photosensitivity when 2-alkylanthraquinone or 4-morpholino-2, 5-dibutoxybenzenediazonium salts were used as cross-linking reagents.

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