The fluorination polyethylene treated by fluorine-containing gas (F₂ concentration 10%, 10h, at room temperature) showed good heat oxidation resistance values. When a partial discharge of 10 hours was applied to the fluorinated polyethylene, no formation of carbonyl groups nor any weight-loss was observed, indicating that the fluorine gas treatment improved the partial discharge resistance by six times compared with untreated polyethylene. The chemical shift in bonding energy during the fluorination is discussed based on ESCA measurements. The fluorine content in the treated polymer was found to be controllable effectively with gas concentration, time and temperature in fluorination. Thus the present fluorination treatment of the polyethylene powder may provide a polymer suitable for the cable coating which is resistant against the partial discharge, but has mechanical stiffness like that of untreated polyethylene. The partial discharge resistance was interrelated to the crystallinity of the polymer analyzed from the X-ray diffraction and infrared absorption methods.

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Complex composite films were prepared by adding acrylamide (AAm) and water to sodium montmorillonite (Mont) or to sodium fluor-tetrasilicic mica (TSM). Adsorption and polymerization of AAm in the films were investigated. The interlayer specing of the film was 9.6Å for the Mont-complex and 8.8Å for the Na-TSM complex as determined by X-ray diffraction measurement. The quantity of crystals in the film was caluculated from the heat of fusion of AAm by differential scanning calorimetry (DSC). The quantity of AAm crystals determined by DSC was found to be considerably smaller than that of initially added AAm. The quantity of uncrystallized AAm was nearly equal to that of AAm intercalated into the interlayer space, 1/K. The AAm-crystals are located on the surfase other than the interlayer space. The AAm in the films was polymerized upon gamma-ray irradiation. The extent of polymerization increased almost linearly with the irradiation time. The interlayer space of the film polymerized did not change from that of the unirradiated film.

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The relationship between cross-linking density and physical properties was investigated for cured epoxy resins. These resins were prepared by using poly (glycidyl ether) of o-cresol-formaldehyde novolacs having different molecular weights, a phenol-formaldehyde novolac hardener, and various accelerators. The cross-linking density of the cured resins is higher for raw epoxy resins of higher molecular weight. The density reached the highest value when 2-ethyl-4-methyl imidazole was used as an accelerator. The thermal expansion coefficient of the cured resins in rubbery state decreased with higher values of cross-linking density, while it increases in the glassy state. The elasticity values of highly cross-linked resins in glassy state are lower than those of low cross-linked resins. Furthermore, the saturated water content, water vapor permeability and diffusion coefficient and specific volume increase as the cross-linking density becomes higher. Such relationships between cross-linking density and physical properties were observed in the cured resins which were prepared by using the raw epoxy resins having different molecular weights and in the cured resins prepared by using different accelerators.

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Preliminary experiments showed that polyethyleneimine (PEI) could be combined fairly well with glass or other several substrates. We became then interested in examining whether the PEI would be applicable as the pretreating reagent of electroless plating instead of aminosilane. Glass beads and three hydrophobic polymer coating beads were tried as the sudstrates. The amounts of PEI combined with substrates and of palladium ion adsorbed on their resultant PEI coating beads were evaluated by XPS and atomic absorption analyzer, respectively. Whether or not electroless nickel deposition would occur on their Pd²⁺ bound beads was also examined. PEI could combine excellently with glass and hydrophobic polymer substrates and the palladium ion also was adsorbed well on the resulting PEI coating beads. When the Pd²⁺ bound beads were immersed into plating bath, nickel began to deposit after a certain time interval as was observed previously. The usefulness of PEI instead of aminosilane as the pretreating reagents of electroless plating is suggested.

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Methyl methacrylate-p-styrenesulfonic acid copolymers (MS) was prepared to develop a new adhesive to both tooth substrates and dental resins which were made of methacrylates. The adhesion mechanism of MS to tooth substrates was elucidated. The effect of metal ions on the viscosity of the copolymer solution was observed. The reaction of the copolymer with the hydroxyapatite was studied by FT-IR spectroscopy. The ground bovine tooth enamel surfaces were applied with 3% of aqueous MS, washed with water, and then characterized by XPS. The FT-IR spectra indicated the reaction of sulfonic acid in MS with the hydroxyapatite. The XPS analysis showed that the MS could not be removed from the surface by washing. It could be concluded that the adhesion of dental resin to tooth with MS was of a new type of adhesion mechanism.

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The St₂·McBA·St₁·McBA·St₂-type block-graft copolymers of butyl acrylate macromer (McBA) with styrene (St) were prepared by the photoiniferter technique. The microdomain structure of hot-pressed samples of the blockgraft copolymers was investigated in terms of dynamic viscoelastic properties, electron microscopy, and tensile strengths. The microdomain structure depended not only on the length of both St₁ and St₂ blocks but also on the molecular weight of the macromer. Thus, the St phase transformed from a continuous phase into a dispersed phase, and the BA phase similarly changed. It was found that the dynamic viscoelastic properties and the tensile strengths varied with those microdomain structures.

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The polymerization mechanism and the surface structure of styrene (ST) -glycidyl methacrylate (GMA) copolymer latices prepared by a soap-free seeded emulsion copolymerization method were investigated. During the first stage, a mixture of ST and GMA was polymerized to form seeded particles, and then ST was added dropwise to grow the seed particles. In this polymerization process, ST added in the second stage was dissolved into the aqueous medium, and was then absorbed and diffused into the seed particles. In the polymerization process of this adsorbed ST monomer, the hydrophobic polystyrene domains undergo phase separation against the GMA-rich copolymer domains formed in the first polymerization process, inducing the polymer latices with segregated hydrophilic domains at its surface. This phenomenon was confirmed by the polymerization behavior, the surface analysis based on the soap-titration of the latices, and the morphological analysis of the cross section of the latices.

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Solid-state polymerizations of two kinds of liquid-crystalline acrylic monomers, i. e., 4′- [ (S, S) -2, 3-epoxyhexyloxy] phenyl 4- (acryloyloxy-alkyloxy) benzoate, in which the alkylene spacer is hexamethylene or undecamethylene, by low-energy electron beams were studied to examine the effects of irradiation temperature and the phase. The conversion of liquid-crystalline monomers to polymers in several phases, i. e., crystal, liquid-crystal, and isotropic melt, was investigated. The conversion depended on the phase rather than the temperature and increased in the order of crystal, isotropic melt, and liquid-crystal state. Solid-state polymerization of two kinds of non-liquid-crystalline monomers in the presence of a liquid-crystalline compound (4′-hexyloxyphenyl 4- (propanoyloxy-hexyloxy) benzoate) (HPHB) was examined. The conversion of a monomer having the phenyl benzoate moiety increased with increasing content of the liquid-crystalline compound, but that of a monomer without the phenyl benzoate moiety did not depend on the content. It was suggested by polarizing microscope and DSC measurements that HPHB assisted aggregation of the non-liquid-crystalline monomer with the phenyl benzoate moiety to cause the increased conversion.

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Terpolymerizations of α-methylstyrene (MS) and acrylonitrile (AN) with N-phenylmaleimide (PMI) or N-p- chlorophenyhnaleimide (CPMI) were carried out by dropping a solution of different amounts of PMI or CPMI in cyclohexanone into the MS-AN copolymerization system in the presence of radical initiator at 80°C. Five terpolymers containing about 3 to 17 mol% of PMI or CPMI units were obtained. The thermal behavior of the terpolymers was examined by TG and DSC measurements. In both series of terpolymers, the glass transition and initial thermal decomposition temperatures and softening point increased markedly with increasing PMI or CPMI composition in the terpolymers.

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Non-enzymatic heterogeneous hydroxylation of benzene into phenol in the presence of L-ascorbic acid and oxygen was studied. We used of solid polymeric catalysts such as poly (methyl methacrylate) (PMMA), poly (methyl vinyl ketone) (PMVK), and ion-exchange or chelate resins that carry supported Fe²⁺ or Cu⁺ ion to mimick the hydroxylase. The reaction was strongly affected by the polymeric catalyst systems. When the hydroxylation was repeated three times in the same batch reactors, the phenol yields with the PMMA and PMVK catalysts were 20 times higher than in their absence.

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