Ionic conductivity measurements of ZrF₄-BaF₂-MF_n fluoride glasses were carried out to examine the relationship between glass-constituents and fluoride-ion conduction in fluorozirconate glasses. Twelve metal fluorides such as LiF, NaF, RbF, CsF, CaF₂, SrF₂, BaF₂, SbF₃, BiF₃, LaF₃, NdF₃, and HfF₄ were chosen as the MF_n components and four teen kinds of glasses in four compositions were submitted to the ionic conductivity measurements. The measurements were carried out in the temperature range from room temperature to glass transition temperature in argon atmosphere using the complex capacitance and complex impedance methods.
The ionic cond uctivity of glasses, represented by log σ=log σ₀-ΔE/2.303 kT, was nearly dependent only upon the activation energy. The polarizability of cation was found to he a dominant factor which governs activation energy. Thus, glasses with high mean polarizability of glass-constituting cations exhibited high ionic conductivity, and the ZrF₄BaF₂-CsF system was suggested to be a promising system that may provide a glass with higher fluoride-ion conduction.

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Fluorine-carbon fiber intercalation compounds were prepared in the presence of lithium fluoride, and their electrical conductivity and air stability were investigated. Most of the prepared compounds were the mixture of 2 nd and 3 rd stage, C₈∼₁₀F (d_cpu=9.4, 12.7Å) or the 3 rd stage, C₁₀∼₁₃F (d_cpu=12.7Å). The 3 rcl stage compound gave the highest conductivity of 2.5×10⁴S⋅cm^-1 which was 8 times higher than that of pristine pitch fiber, 3.1×10³S⋅cm^-1. The air stability of the compound increased with increasing intercalated fluorines. ThE electric conductivity of C₈.₈F decreased by 22% after 80 d and by 28% after 200 d. The change in the X-ray diffraction lines coincided with the decrease in the electric conductivity.

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Electrolytic production of NF₃ on various anodes was carried out at 120°C in molten NH₄F-HF-(NH₂)₂CO and molten NH₄F-HF-KF-(NH₂)₂CO systems by a few kinds of electrochemical methods. Either carbon or graphite was used as an anode and Pt-rod was used as a reference electrode. Anode gas was analyzed by both gas chromatography and infrared spectroscopy.
The anodic polarization curves obtained by the galvanostatic method in the NH₄F-HF(NH₂)₂CO system showed that a favourable molar fraction of urea was less than O.008 in order to decrease direct discharge of urea. From the anodic polarization curves obtained in the NH₄F-HF-KF system, it was also found that the molar fraction of KF added in the melt should be O.233 at minimum to prevent HF from permeating through the anode. When urea was added in the molten NH₄F-HF-KF system, evolution of CO₂ gas occurred due to the reaction of urea with H₂O in the melt. In the electrolysis at the potential between 4.5 V and 5.5 V (the region of electrofluorination), anode gas was mainly composed of N₂, CF₄, NF₃, CO₂, N20. Under the electrolytic conditions of current density of 15mA⋅cm^-2 and urea-molar fraction of 0.004, NF₃ was detected in the anode gas after electrolysis for 6 h and its composition ratio of anode gas, i. e. yield, reached to the maximum value of 87% after 70 h.
These results indicate that the addition of urea in the melt is effective for increasing the current efficiency of NF₃ because of the elimination of H₂O in the melt by hydrolysis of both urea and COF₂ which is one of the anodic products.

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Fluorinated active carbon fibers (F-ACF's) were prepared from active carbon fibers (ACF)by direct fluorination with elemental fluorine at low temperatures ranged from 20 to 200°C. With increasing temperature, the color of compounds varies from black through brown and yellow to white. The interaction between carbon and fluorine atoms in F-ACF's has been studied by ESCA, ¹⁹F-NMR and IR spectroscopies. Oxidizing ability of F-ACF's has also been measured by iodometry.
The nature of C-F bond in F-ACF's varies from physical adsorption to completely covalent bond depending on the reaction temperature as follows. ( 1 ) In F-ACF's prepared at temperature below 50°C, one third of fluorine atoms are liberated easily and oxidize iodide ions. Another two thirds of fluorine atoms form weak covalent bonds with carbon atoms including charge-transfer interaction in some extent. ( 2 ) In ACF's obtained at 100°C, the fraction of fluorine atoms which can oxidize iodide ions is less than 1% of all of the fluorine atoms. Almost fluorine atoms are covalently bound to carbon atoms, but the strength of these covalent bonds is widely distributed as in the case of F-ACF's obtained at temperatures below 50°C. ( 3 ) In F-ACF's prepared at 200°C, the C-F covalent bond is completed as well as that of graphite fluoride. F-ACF's obtained at this temperature are an admixture of like graphite fluorides, (CF)_n and (C₂F)_n.
These variations in the nature of C-F bond infer the color change of the compounds by fluorination temperature.

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Tungsten carbide films were prepared at 300∼700°C by the reactions of the ternary system, WF₆+H₂+hydrocarbon (benzene, cyclohexane, 1, 3-butadiene or butane), and the effect of hydrocarbon on formation of tungsten carbide was investigated. It was found that, among the above four hydrocarbons whose thermal decomposition temperatures range from ca.450 to 650°C, the unsaturated and/or cyclic hydrocarbons were more preferable than the saturated and/or chain compounds for preparation of tungsten carbide. Pure W₂C films were prepared from benzene and cyclohexane at 450 and 550°C, respectively, and their deposition rates were much higher than those of chain hydrocarbons. The highest hardness (2700∼3400 HmV) was observed for the film prepared around 550°C in which the deposition rate was also very high. Tungsten nitride, W₂N was obtained by the thermal decomposition of an adduct of WF₆⋅4 NH₃ at 700°C under the NH3 or argon gas flow.

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The structures of molten LiF-KF (mole ratio 1:1) mixture at 545°C and LiF-NaF (3:2)mixture at 690°C were investigated by an X-ray diffraction analysis. In the LiF-KF (1:1)system, the nearest neighbour distances and coordination numbers of unlike ion pairs were 1.85 A and 3.0 for Li⁺-F^- ion pair and 2.70 A and 4.1 for K⁺-F^- ion pair, respectively, which were found to be nearly equal to those analyzed in each pure melt. In the LiF-NaF (3:2) system, the nearest neighbour distances and coordination numbers of unlike ion pairs analyzed were 1.84 A and 3.0 for Li⁺-F^- ion pair and 2.20 A and 3.8 for Na⁺-F^- ion pair, respectively, which were almost the same as those determined in each pure melt. These results imply that the nearest neighbour structures of unlike ion pairs are similar to those of the constituent salts, i. e., they ar e unaltered by mixing process of the two fluoride melts.

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Plasmid pU0 1 encodes two kinds of haloacetate dehalogenases, H-1 and H-2; H-1 acts on fluoroacetate but H-2 does not. DNA-DNA hydridization experiments demonstrated that there is no homology between the H-1 and H-2 genes. This indicates that there is no evolutionary relationship between the two dehalogenases. Many bacteria assimilating fluoroacetate, chloroacetate, or 2-chloropropionate were isolated. The isolates capable of defluorinating fluoroacetate were all found to contain a H-1-like dehalogenase and a gene homologous and were perhaps essentially identical to the H-1 gene, suggesting that bacterial dehalogenases acting on fluoroacetate are considered to be only one species

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The mixed adsorption of perfluorohydrocarbon, C₈F₁₇SO₃Li, (LiFOS), and hydrocarbon, C₁₄H₂₉SO₄Li, (LTS), surfactants at the air-water interface was studied in orde r to clarify the compositions of an adsorbed film and a micelle. The LTS in an adsorbed film was measured at 30°C by radiotracer method using ³H-labeled compounds. The adsorbed amount of LiFOS was estimated by the Gibbs adsorption isotherms applied to both single and micellar solutions. The micelle compositions at the CMC were computed by the Shinoda's theory for a mixing micelle. It has been concluded that at the CMC the fraction of the hydrocarbon surfactant in the micelle is higher than that in the adsorbed film. Also, the radiotracer study indicates that the adsorbed amount of LTS decreases with increasing bulk concentration beyond the CMC, whereas the adsorbed amount of LiFOS increases. The results can be interpreted by the fact that the concentration change based on the single species of LiFOS takes place with increasing bulk concentration of the mixed solutions, though the micellar compositions are not varied.

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The Shirakawa River which has Aso caldera as the drainage basin is a representatible of intermediate scale river which flows through a volcanic rock region.
The present study is the elucidation of the variation in fluorid e and chloride ion contents in the river water at the single point of the Shirakawa River, based on the chemical analysis of the river water samples taken from 1975 to 1984. Especially daily samples were collected at Meigo-bashi in Kumamoto City, day by day from May in 1975 to April in 1976.
The measured values vary with time (Fig.2 and 3). The contents of fluoride and chloride ion were found to be in the range of 0.36∼1.33 mg/l (arithmetic mean 0.70 mg/l) and 2.5∼16.6 me (arithmetic mean 12.5 mg/l) for daily 366 samples, respectively. The correlation coefficient between fluoride and chloride ion contents was +0.437; thus there was a slight positive correlation. The mean value of fluoride ion contents in the Shirakawa River water was abnormally high and became about 10 times larger than that in the entire Kyusyu region as reported by Onishi (1979).
The fluoride ion contents in the river wa ter of main and tributaries in the Shirakawa River which flow through Aso central cones and Aso caldera wall were found to be in the range of 0.35∼3.26 mg/l and less than O.16 mg/l, respectively.
The fluoride and chloride ion contents decreased with increasing the flow rate and rainfall in Aso region. However, the extent of the reduction of fluoride ion content was not so pronounced as that of chloride ion content.
Ten-year variation in fluoride and chloride ion contents was small, except for 1979 when the Shirakawa River drainage basin was affected by Aso volcanic activities.
As the results, it is considered that the origin of fluoride ion in the Shirakawa River water is attributed to volcanic activities including those in the past.

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Perfluorooctyl bromide (PFOB), a biologically inert radiodense compound, was evaluated as a potential contrast agent for tumors. When 25 w/v% PFOB emulsion was administered intravenously in rats with AH 130 tumor, the tumor became radiopaque using conventional X-rays. Rabbits were implanted into liver with VX 2 carcinoma and were given 10 m//kg PFOB emulsion intravenously. Computed tomographic scanning of the rabbits showed the dense enhancement of the rim of the tumor. The PFOB contents in the tumor, the tumor-rim and the normal liver tissues were determined by gas chromatography. The differences of PFOB contents in three different locations showed the density of the tumor rim was due to the accumulation of PFOB in the periphery of the tumor. Optical and electron microscopy revealed lots of vaculoes of PFOB particles in macrophages around the tumor. Thus, PFOB emulsion may be useful in detection of tumors.

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The spin lattice relaxation time (T₁) of ¹⁹F-nuclear spin in molten LiBeF₃ was measured at frequency of 20 MHz by means of the pulse NMR technique. T₁ becomes a minimum at about 550°C and T₁^-1 can be expressed as τ/(1+ω₂τ₂), where τ is the correlation time and is estimated to be 1.9×10^-15 exp (100×10₃/RT) S. It is suggested that the relaxation mechanism of ₁₉F- in molten LiBeF₃ is due to the dissociation of F ions from [BeF₄] complex ions and the long distance diffusion of F ions in the liquid. At lower temperature the other mechanism prevails, that is, the main contribution to T₁^-1 is the rotation of the complex ions.

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A basket type carbon electrode had the dimensions of 15 cm is diameter, a depth of 8 cm and a wall thickness of 0.5 cm with fifty holes (φ5cm) on the wall. A coil of iron net (5 mesh) was used as a cathode. An electrolytic cell made of maild iron had the dimensions of 30 cm in diameter, a depth of 17 cm and a wall thickness of 1 cm. The electrolyte used was 15 kg of KHF₂, and the bath temperature was kept at 300±10°C. A felt of carbon fiber (60g) was charged in the basket type electrode which was fluorinated in advance. Fluorination was conducted for about 4∼5 h with 10 A (about 11mA⋅cm^-2). The colors of fluorinated fibers varied from black through brown, blue, yellow, violet and gray to white with an increase in the degree of fluorination. The specific gravities of carbon fibers after the electrolysis were from 1.62 to 2.50g⋅cm-3. The heats for wetting for water at 25°C were from 2.06 to 0.59J⋅cm-2, and the value decreased with increasing the degree of fluorination. The contact angle against water was about 140°. The thickness of fluorinated fibers observed from 0.25 to 0.45μm by Scanning Electron Microscope. Identification of the products was not comfirmed yet, but formation of carbon fluoride was considered to be evident.

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Disinfection effects of electrodialysis systems using a cationic type fluorinated membrane (Nafion-415) on E. coli cells have been investigated.
E. coli suspended in various electrolyte solution (10⁸ cells/cm³) were passed through a desalting chamber at a flow rate of 3 cm/min at different current densities, and viability (%) in the effluents was determined.
Remarkable disinfection effects were observed for the Nafion-415 system compared with the system of a usual cation-exchange membrane (CMV). For example, the E. coli cells suspended in 0.1 mol⋅dm^-3 NaCl solution were perfectly devitalized after 20 min of the electrodialysis at the current density of 1.63 A/dm².

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Thermodynamic properties and thermal stability of working fluids used in Rankine cycle systems and heat pumps were studied.
Five fluids, R 114, 2, 2, 2-triflu oroethanol, 2, 2, 3, 3-tetrafluoro-1-propanol, 2, 2, 3, 3, 3-pentafluoro1-propanol and azeotropic mixture of the pentafluoro-l-propanol with water were chosen as working fluids and their thermodynamic proparties and cyclic properties were investigated at 140∼200°C.
The results showed that pentafluoro-l-propanol could exibit the maximum gross and net output above 180°C with neither possible inflammability nor deterionaion of thermal stability.

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2-Fluoroacrylonitrile (α-FAN) has been synthesized and homopolymerized by bulk and solution methods. The poly(α-FAN) is a white solid and soluble in various aprotic polar solvents, tetrahydrofuran, and acetone at room temperature. Dehydrofluorination and intramolecular cyclization occurred when poly(α-FAN) was heated to 250∼300°C. The glass transition temperature (T_g) of poly(α-FAN) was observed to be 101°C by thermomechanical analysis (TMA). The relative reactivity ratios in a-FAN (M₂) copolymerization with styrene (St) (r₁=0.44, r₂=0.03) were obtained. Application of Q-e scheme led to Q=0.43 and e=1.28 for α-FAN.

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Perfluoroalkyl (R_f) groups could be directly introduced into some phenyl groups of poly(α-methylstyrene) (Pα-MeSt) or poly(phenyl methacrylate) (PPhMA) without fission of the polymer chains by treating these polymers with (perfluoroalkyl)phenyliodonium triflates (FITS) at 75∼80°C in presence of pyridine using a mixture of chloroform and acetonitrile as a solvent. R, groups introduced into the polymers were C₂F₅, i-C₃F₇, n-C₄F₉ or n-C₆F₁₃ groups (Table 2 and 3). The yields (1O∼36%) were, varied depending on the polymers, R_f groups and the reaction conditions.
The electron beam exposu re experiment of the R_f-Pα-MeSt revealed that the electron beam exposure increased the molecular weight of the R_f-Pα-MeSt(negative type) in contrast to Pα-MeSt which was degraded(possitive type) (Fig.4). On the other hand, deep UV irradiation to R_f-Pα-MeSt resulted in the fission of the polymer chains (Fig.5). The R., PPhMA was also a negative type polymer toward the electron beam (Fig.6). It was suggested that reactive species in such crosslinking reactions were α, α-difluorobenzyl radicals [C4].

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The surface modification of poly(vinylidene fluoride) (PVdF) and ethylene-propylene copolymer (EPDM) by CF₄ and argon plasma treatment has been studied using ESCA. The CF₄-plasma treatment increased or introduced fluorine but not oxygen onto the polymer surfaces (Figs.2, 3, 4, 6, 7, and 8), and functional groups were shown to be CF₃, CF₂, and CF from the curve resolution of the Cis spectra (Fig.12 and Table 2). The CF₄treatment gave high advancing contact angles of water (Figs.3, 4, and 7) and low coefficient of static friction for Teflon (Table 1), indicating that this treatment is an appropriate method for decreasing wettability and friction of polymer surface. The CF₄-treated PVdF surface was considerably stable in water (Fig.10), but the EPDM surface gave a pronounced change in surface elemental composition and contact angle (Fig.11). The argon-plasma treatment produced oxygen incorporation onto the polymer surfaces, along with a concomitant decrease in fluorine for PVdF surface, and low contact angles (Figs.5 and 9). The oxygen incorporation was considered to be due to the post-plasma surface reaction with atmospheric oxygen.

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A novel fluoromonomer with two long polyfluoroalkyl chains, 1 H, 1 H, 2 H, 2 H-perfluorodecyl 2-(9-trifluoromethyl-(1 H, 1 H, 2 H, 2 H-perfluoroundecyal))acrylate [1] was successfully prepared. The copolymerization of [1] with methyl methacrylate (MMA) was studied and monomer reactivity ratios were obtained as follows: r(MMA) =2.8±0.5 and r [1]=0at 60°C. The copolymer films of [1] with MMA were examined in wettability and ESCA measurements on their air/solid and mercury/solid interfaces. As to the air/solid interface, an incorporation of a small amounts of the monomer [1] unit in the copolymer was found to make the wettability low steeply, an incorporation of the 0.8∼1.0 mol% monomer unit allowed the wettability of a limiting value as low as that of the homopolym e r film of monomer [1], and further incorporation of monomer [1] unit led to no more change in the wettability. On the other hand, as to the mercury/solid interface, the wettability was found to decrease proportionally with the content of the monomer [1] unit; an incorporation of so small amount of the monomer [1] unit as 1.0 mol% giving no effective change in the wettability from that of polyMMA film. The values in ESCA measurement corresponded well with the results of wettability measurement. It was supposed that the polyfluoroalkyl chains in the copolymers would be selectively and exclusively concentrated and orientated at the air/solid surface region to make it less wettable. In this regard the new fluoromonomer with two long polyfluoroalkyl chains was found to be more effective than the fluoromonomers [1] with one polyfluoroalkyl chain as reported previously.

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Plasma-polymerized thin films were prepared on the porous substrates from perfluorobenzene (PFB) monomer which has good affinity to oxygen. Their aggregation states and oxygen permeation properties were investigated. On the basis of thermogravimetric measurements, infrared absorption spectra and X-ray photoelectron spectra, it became apparent that the aggregation structure of the plasma-polymerized films highly depended on radio-frequency (RF) power to sustain plasma, the substrate temperature and the annealing time after deposition. The structure containing unsaturated bond or aromatic group changed into a highly cross-linked structure containing saturated bond with an increase in the variables mentioned above. The oxygen permeation rate through the plasma-polymerized PFB films deposited on Millipore decreased drastically and on the other hand, the separation factor remarkably increased in the vicinity of 0.15∼0.3μm in thickness as shown in Fig.9. The permeation properties indicate that pinhole-free thin films were formed in the region of this thickness. Since the plasma-polymerized film has heat-resistant property because of its highly cross-linked structure, PFB was deposited on the porous ceramics in order to prepare the heat-resistant oxygen enrichment membrane. Fig.11 shows the Arrhenius plots of permeability coefficient and the separation factor of O₂ and N₂ gases in the temperature range from 283 to 573 K for these membranes. The oxygen permeability coefficient for the film which was polymerized at RF power of 100 W and the substrate temperature of 573 K remained almost constant at about 2× 10^-8cm³ (STP)⋅cm^-1⋅s^-1⋅cmHg^-1 in the temperature range studied here, and also, the separation factor gradually decreased from the magnitude of 4.5 at 283 K with an increase in temperature. This result indicates that an excellent oxygen enrichment film can be prepared by means of plasma polymerization.

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The oxygen enrichment property of polymer/liquid crystal composite membranes containing fluorocarbon was investigated. Fluorocarbon monomer(FC), for example, perfluorotributylamine(PFTA), was contained in the micells formed by a surface-active agent(SAA). The polymer/liquid crystal/FC ternary composite membrane was prepared by casting a tetrahydrofuran solution of a mixture of poly(vinyl chloride) (PVC), N-(4-ethoxybenzylidene)-4'butylaniline(EBBA) and FC. On the bases of differential scanning calorimetric measurement, extraction test, and scanning electron microscopic observation, the aggregated state of the polymer/liquid crystal/FC ternary composite membrane resembled that of the FC-free composite membrane. That is, EBBA molecules interpenetrated through the three dimensional spongy networks of PVC matrix, forming a continuous phase.
The oxygen permeability coefficient, P_O2 for the PVC/EBBA/F C ternary composite membrane is greater than that of the FC-free one. In the case of the ternary composite membrane containing PFTA(7.2 parts), a remarkable oxygen enrichment effect was observed. The order of P_O2 was 10^-9-10⁸ cma(STP)cm^-1⋅s^-1⋅cmHg^-1 and the magnitude of the permeability coefficient ratio (P_O2/P_N2) was 3.5∼4.0 in the nematic or isotropic state of EBBA. These facts indicate that FC plays a role of enhancing solubility of oxygen in the composite membrane surface. The ternary composite membrane exhibited an unique behavior which revealed an increase in P_O2/P_N2 as P_O2 increa sed above the glass transition temperature of the matrix polymer. This effect is considered to be caused by a desirable combination of the thermal molecular motions from both the matrix polymer and the liquid crystalline material. The unique relationship between P_O2/P_N2 and P_O2 of the composite membrane lead it to a practical application as oxygen enrichment membranes in the medical and engineering fields.

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The reaction of a monomeric perfluoroalkanesulfonyl chloride with reducing agents provides a carboxylic acid in lower yields under the appropriate conditions, whereas in a perfluoro polymer with chlorosulfonyl group, the sulfonyl chloride is desulfurized to form a carboxylic acid in extraordinarily high yields. Ion-exchange capacity of a polymer does hardly change before and after the reaction, so a loss of ion exchange group does not occur throughout the reaction. Infrared spectra of films treated with various reducing agents suggest that this reaction is two-step reaction, and that carboxyl group is formed via sulfino group. It is supposed that high selectivity and conversion are due to difference of the circumstances around reactive sites in polymer from those in monomer.
This reaction can be applied for the preparation of the double layer membrane having both carboxyl sulfo groups for salt electrolysis with high current efficiency and low membrane voltage.
Membranes with various thickness of carboxylic acid layers are obtained by treating one side of the membrane containing chlorosulfonyl group with reducing agent. Performances of those membranes show that current efficiency, membrane voltage and water transprot depend on the thickness of carboxylic acid layer. The thicker the carboxylic acid layer, the higher the current efficiency and membrane voltage and the lower the water transport. The thickness of at least 7 microns of carboxylic acid layer is needed to get a good performance.

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Investigations on the compatibility and piezoelectric behavior depending on the conformational changes in copoly(vinylidene fluoride-trifluoroethylene) P(VDF-TrFE) crystals were carried out in the polymer blends of P (VDF-TrFE)/poly(methyl methacrylate) (PMMA) system. From the thermodynamic treatment, the interaction parameters, X12, for the pair is found to be -0.329uat 150°C, indicating that the system is compatible as well as poly(vinylidene fluoride) /PMMA system. The results from X-ray diffraction, DSC, infrared spectra and TSC measurements show that the ferroelectricity is observed even in P(VDF-TrFE)/PMMA blends at the weight fraction of P(VDF-TrFE) higher than 65% with the crystal form corresponding to the form I in poly(vinylidene fluoride). According to the analyses of IR spectra and DSC as well as the piezoelectric behavior, it is considered that the polar crystals of the all trans conformation are decrystallized less efficiently due to the weaker interaction with the metoxy carbonyl group in PMMA, compared with the nonpolar crystals of the gauche conformation.

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The surface of the functional polymers listed in Table 1 and of aluminum was modified in CF₄ plasma generated with either radio-frequency (r. f., 13.56 MHz) or microwave (m. w., 2450 MHz) glow discharge. Samples were placed into the discharge field (on the grounded electrode) in the case of r. f. plasma treatment and were placed 13 cm below the cavity in the case of m. w. plasma treatment.
The results of contact an gle measurements, shown in Figs.4 and 5, prove that the polymer surfaces treated in CF₄ plasma become at least as hydrophobic as poly(tetrafluoroethylene)(PTFE) surfaces in very short treatment time. The modified surface layers contained a lot of fluorine atoms, most of them united with carbon atoms (Fig.8, Tables 3and 4).
However, a difference in the modifying process was discovered between r. f. and m. w. treatments. The r. f. -treated samples exhibited weight loss (Fig.1) and rough surface (Photo.1) because of etching. In contrast to this, deposits from CF₄ plasma were formed on the m. w. -treated samples.
Aluminum plates co ated with CH₄ plasma were exposed to CF₄ plasma. This is a new try to deposit the layers of graphite fluoride, which has the lowest surface energy, on metal surfaces by means of plasma treatment. The results of surface analyses suggest that this method is hopeful.

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Physical properties of poly(fluoroalkyl methacrylate)s and poly(fluoroalkyl 2-fluoroacrylate)s were investigated. The refractive index decreases with increasing the fluorine content of the polymer. The observed values of refractive index reveal good agreement with the values calculated by using the Lorentz-Lorenz equation. The glass transition temperatures of polylfluoroalkyl 2-fluoroacrylate)s are 20-30°C higher than those of poly(fluoroalkyl methacrylate)s and the difference seems to be attributed to the difference in the intermolecular interaction. The Young's modulus of poly(fluoroalkyl 2-fluoroacrylate)s are lower than those of poly(fluoroalkyl methacrylate)s in spite of the higher glass transition temperature. Furthermore poly(fluoroalkyl 2-fluoroacrylate)s show higher thermal stability than poly (fluoroalkyl methacrylate)s.

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The composites of polymers and piezoelectric ceramics have recently been attracting much attention because the composites have flexibility as well as piezoelectric activity.
The phase connectivity is particularly important in piezoelectric property of the composites. A model of the two-phase system with spherical dispersions was applied to the composites of fluoro polymers and lead zirconate-titanate(PZT) ceramics. For the PZT/vinylidene fluoride and trifluoroethylene copolymer(VDF/TrFE) system, a strange behavior of the piezoelectric d-constant to the volume fraction of PZT ceramics was observed, which is explained by a modified model of the system with spherical dispersions.

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Fluoro polymers have been used as biomaterials in medical field since they have good compatibility with both tissue and blood, and their biomaterial application are of variety. Blood compatibility of fluoro polymers, however, are not always enough for every applications. Especially, there is a large difficulty in the application for artificial vessel with small radius below than 4 mm.
In the pres ent study, grafting of a hydrophilic monomer onto a fluoro polymer has been carried out to improve blood compatibility of the fluoro polymer. The technique of grafting employed here was simultaneous irradiation method of gamma rays from a ⁶⁰Co source. The fluoro polymer and the hydrophilic monomer used in the experiment were alternative copolymer of ethylene and tetrafluoethylene(AFLON) and N, N-dimethylacry lamide(DMAA), respectively.
After grafting, it was found by in vitro tests that antithrombogenicity of AFLON was improved by grafting of DMAA. It was, however, also found that degree of the improvement is affected by grafting conditions. When ethyl acetate was used as a solvent for the graft copolymerization, the improvement was affected by dose rate. Blood compatibility of DMAA-g-AFLON obtained at a higher dose rate of 1×10⁵ rad/h was not improved, while it was improved in the sample of DMAA-g-AFLON obtained at a lower dose rate of 1×10⁴ rad/h. On the other hand, when acetone was used as a solvent for the grafting, the degree of grafting gave a significant effect on the improvement. Blood compatibility of all samples with grafting percent more than 20% was improved by grafting of DMAA.,

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The anionic polymerizations of hexafluoroisopropyl acrylate and methacrylate were examined in the course of the investigation on the polymerization reactivity of fluorine-containing vinyl monomers. Butyllithium and organomagnesium compounds were found to yield the polymers of hexafluoroisopropyl methacrylate. Ate complexes such as LiZnC₄H₉(C₂H₅)2 and LiAlC₄H₉(C₂H₅)3 initiated polymerization reaction and produced high molecular weight po lymers (M_GPC: 1.3×10⁴) of hexafluoroisopropyl methacrylate. This monomer was also polymerized quantitatively with the initiator of triethylaluminium in toluene media. This phenomenon suggests that its polymerization reactivity might be as high as that of vinyl ketones. Hexafluoroisopropyl acrylate was less reactive toward the polymerization initiators which could yield the polymers of hexafluoroisopropyl methacrylate.

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Surface characteristics of perfluorinated cation-exchange resins (Nafion) were investigated by the measurement of heats of immersion in 1-nitropropane, hexane and water. Electrostatic field strengths (F) calculated from the heats of immersion increased with increasing ratios of the exchanged multivalent cation (La³⁺) in the univalent form (H⁺) cation-exchange resin, but the values of F were far smaller than those of usual hydrocarbon-based cationexchange resins (Amberlyst-15). This result suggests that the surfaces of the Nafion are far hydrophobic and states of the exchange sites are different as compared with those of the Amberlyst-15.

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Solutions containing 14∼23% weight percent of melamine in anhydrous hydrogen fluoride have been found to be stable and more convenient fluorinating agents for alkenes and alcohols, being superior to other organic amine-hydrogen fluoride reagents. The reagent with such a co-solvent as pentane or carbon tetrachloride, which forms a liquid-liquid two phase mixture, revealed to be a versatile and highly advantageous system for a repeated use in continuous hydrofluorination of alkenes.

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Bis(heptafluorobutyryl) peroxide [1] has been widely used as an initiator of radical polymerization of vinyl chloride or fluorine-substituted olefins. However, the study on the decomposition of [1] itself is few. Mechanism of the decomposition of [1] was investigated by reaction rate study. The homolytic decomposition of [1] easily occurred in comparison with that of the corresponding nonfluorinated diacyl peroxide. The peroxide [1] underwent readily decomposition induced by nucleophilic reagents such as benzenes with electron-donating substituents or water (Fig.1 and Table 1). This property may be attributed to that the high electronegativity of perfluoroalkyl group lowers the energy level of antibonding O-O orbital and increases the positive charge on carbonyl carbon atom. The reaction of [1] with benzenes gave perfluoropropylbenzenes in good yields, so the peroxide [1] may be used as a good reagent for perfluoroalkylation of aromatic compounds.

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The reaction of 1, 2, 4, 5-tetrafluorobenzene (TFB) [1] with sodium dihydronaphthylide (C₁₀H₈^-Na⁺) [9] was investigated as a defluorination model of polyfluo rinated aromatic compounds. When [1] was treated in THF at 0°C for 30 min with 1.5 equiv of [9] per fluorine atom, organic fluorine atom was removed effectively (defluorination efficiency: 100%). α, α, α-Trifluorotoluene [2] was also defluorinated effectivelyd (100%) under the same conditions. The defluorination of [1] under N₂ at 50°C in THF with unsolvated KOH which was prepared from C₁₀H₈^-K⁺ afforded 2, 4, 5-trifluorophenol [3] (83.4%) as the major product. Under an oxygen atmosphere, however, 2, 3, 5, 6-tetrafluorophenol. [4] (46.3%) was predominantly produced besides [3] (25.8%). Thus, the initial likely intermediate is 2, 3, 5, 6tetrafluorobenzenide anion, which undergoes either elimination of fluoride ion to generate trifluorobenzyne or air oxidation to yield tetrafluorophenol [4] as the final oxidation product.

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In the presence of excess cesium fluoride, the reaction of the fully protected 5'-0dimethoxytrityl-N-acyldeoxyribonucleoside 3'-[O-(4-chlorophenyl) O'-(5-chloro-8-quinolyl)phosphate]s with 5'-hydroxyl group of N-protected deoxyribonucleosides proceeded selectively under mild conditions to afford the corresponding dideoxyribonucleoside monophosphates in good yields. They were used to demonstrate the synthesis of tetradeoxyribonucleotides by the fragment condensation method.

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The reactions of perfluoro(2-methyl-2-pentene) [1] with alkanediols were investigated in detail. The reaction of [1] with ethylene glycol in the presence of triethylamine gave five- and seven-membered heterocyclic compounds, 2-pentafluoroethyl-2-[1 H-perfluoro(1methylethyl)]-1, 3-dioxolane [5] and 2 H, 2 H, 3 H, 3 H-perfluoro(7-ethyl-6-methy1-2, 3-dihydro5 H-1, 4-dioxepin) [6], as major products.1, 3-Propanediol and 1, 4-butanediol also gave the heterocyclic products [7] and [8], respectively.
On the contrary, 1, 5-pentanediol, 1, 6-hexanediol, and diethylene glycol, which have longer chains than 1, 4-butanediol, afforded the mono and bis[perfluoro(1-ethyl-2-methyllpropenyl] ethers [2a] and [3a] [2b] and [3b], and [4a] and [4b], respectively.

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Electrochemical fluorination of N, N-dimethylakylamines [(CH₃)₂NR; R=C₂H₅ n-C₃H₇, n-C₄H₉, n-O₅H₁₁, t-C₄H₉, c-O₅H₉ and c-C₆H₁₁] and N, N-dialkylmeth ylamines [R₁R₂⋅NCH₃; R₁=R₂=C₂H₅, R₁=R₂=n-C₃H₇, R₁=R₂=n-C₄H₉;R₁=n-C₃H₇, R₂=n-C₄H₉ and R₁ n-C₃H₇, R₂ =n-C₅H₁₁] was carried out.
In the case of N, N-dimethylalkyl amines, yields of perfluoroamines decreased with the increase in the number of carbon atoms of the straight-chain alkyl group due to the cleavage of C-N bond. Isomerization and ring-opening reaction occurred extensively for amines with branched and cycloalkyl groups, respectively.
In the case of N, N-dialkylmethylami nes, it was found that the initial concentration of the amine in anhydrous hydrogen fluoride has great influence upon the yield of the fluorinated amine, which was not the case with N, N-dimethylalkylamines: The higher concentration gave the better results. The β-scission of an alkyl group of amines resulted in the formation of a considerable amount of perfluoro(N, N-dimethylalkylamine). The longer alkyl group in an asymmetric N, N-dialkylmethylamine showed a tendency of such β-scission more easily.

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The reactions of polyfluoroalkyl o-nitrobenzenesulfonates [1a-d] with the various tertiary amines were investigated.
[1 a] reacte d with triethylamine at refluxing temperature (100∼405°C) for 60 h in nitrobenzene to give a 76% yield of (2, 2, 2-trifluoroethyl) triethylammonium o-nitrobenzenesulfonate [2a-I] and an 8% yield of N, N-diethyl-2, 2, 2-trifluoroethylamine [3a-I]. However, the reactions of [1a-c] with the tertiary amines having longer alkyl groups did not occur in the same conditions cited above. At higher temperature (150∼200°C), the quaternary ammonium salts containing polyfluoroalkyl groups were not isolated, and N, N-dialkylpolyfluoroalkylamines [3] and tetraalkylammonium o-nitrobenzenesulfonates were obtained, accompanied with small amounts of olefins and trialkylammonium o-nitrobenzenesulfonates.
The reactions of [1] with N, N-dimethylbenzylamine gave, regardless of chain-length of polyfluoroalkyl groups, good yields (50∼76%) of N, N-dimethylpolyfluoroalkylamines which were difficult to prepare with other methods.
Although the reactivities of N, N-dialky l anilines with [1a] were lower than those of the corresponding trialkylamines or N, N-dialkylbenzylamines, N-alkyl-N-(polyfluoroalkyl)anilines [5] were also formed.

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The reaction of perfluoro(2-methy1-2-pentene) [1] with 1, 1-dimethylhydrazine (DMH)was studied and a series of fluorine-containing pyrazolium aminimines and pyrazoles were prepared. Substituted compound [2] was first given by nucleophilic attack of DMH on [1] followed by proton shift. By debydrofluorination, compound [2] was changed in to a diene intermediate [3] and cyclized to pyrazolium aminimine [4], or condensed to a ketenimine intermediate [3] after changing into [3] and then cyclized to [6], a dimethylhydrazono derivative of [4]. Compound [6] was also obtained by treating [4] with DMI 1, but the reaction rate was small. When [2] was treated with primary amin es, imine derivatives of [4] were obtained as well. By heating, aminimine [4] and [6] which are stabilized with perfluoroalkyl group, were converted to pyrazole [8] and [10], respectively, and were also easily transmuted to pyrazole [8] or [11], and [12], the hydrochloride of [10], respectively, by bubbling hydrogen chloride gas at room temperature. Aminimine [4] was readily hydrolyzed by moisture in the air or the solution, and was changed into aminimine [13] having carbonyl group. Compound [13] was so stable that it did not changed even if heated to 200°C or exposed to hydrogen chloride.

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As a part of our synthetic studies on fluorine-containing aminoglycoside antibiotics, title compounds have been prepared.6''-Deoxy-6''-fluorokanamycin A and 6''-deoxy-6''-fluoroamikacin were prepared from the corresponding N-benzyloxycarbonyl derivatives of kanamycin A and amikacin, respectively, by use of the DAST reagent.1-N-[(R)- and (R5)-3Amino-2-fluoropropanoyl]kanamycins were prepared by coupling, by use of active esters, of 3-benz yloxycarbonylamino-2-fluoropropanoic acids with 3, 6'-bis(N-benzyloxycarbony1)-3''N-(trifluoroacetyl)kanamycin A. To determine the structures of these compounds 2-D NMR spectroscopies were found to be useful. Since the presence of a fluorine atom causes splitting of the nearby connected ¹H- and ¹³C-signals into a (broad) doublet, the spectra of fluorine-containing compounds facilitate the determination of the structures in the vicinity of the fluorine.

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On the purpose of selective preparation of ortho-disubstituted F-benzenes [2] was investigated the reductive cleavage of the heterocyclic ring of 2-phenyl-F-benzoxazole [3], -benzothiazole [4], and -benzimidazole [5] by use of sodium borohydride (SBH), diborane, and lithium aluminum hydride (LAH) in 1, 2-dimethoxyethane (DME). The reactions of [3] and [4] with SBH at room temperature yielded selectively the ring-opening products, 2-benzylamino-F-phenol [6] (isolated in 88% yield) and bis(2-benzylamino-F-phenyl) disulfide [7] (ditto 72%), respectively. The reactions with diborane, which was in situ generated in a DME reaction mixture or was bubbled into a reaction vessel from a separate generator, gave the similar yields as above. In the reaction of [5] with diborane, [5] was recovered quantitatively. On the other hand, LAH displaced the fluorine on the aromatic ring of [4] to give 4, 5, 7-trifluoro-2-phenylbenzothiaxole [10], which was subsequently cleaved at the heterocyclic ring to yield bis(2-benzylamino-3, 4, 6-trifluorophenyl) disulfide [11]. The reductive cleavage of the heterocyclic ring with the boron hydrides seemed to occur characteristically in the F-benzo heterocyclic compounds, because the unfluorinated analogues, 2-phenylbenzoxazole [8] and -benzothiazole [9], gave no ring-opening products under the similar conditions.
The proposed one-pot preparation of [6] from F-benzene [1] and benzamide was shown to afford overall a 60% yield based on the latter.
The reaction route leading to each prod uct was conceivably summarized as shown in Scheme 3.

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Alumina treated with CF₃Cl promoted the vapor-phase alkylation of benzene with CF₃ CH-CH₂ The reaction was carried out by using a continuous flow reactor under an atm ospheric pressure at 100∼450°C. The maximal catalytic activity was obtained when Al₂O₃ was treated with CF₃Cl at about 420°C (Fig.3). The alumina surface was partially fluorinated by the treatment with CF₃Cl, nevertheless the amorphous structure of alumina was almost maintained during the treatment (Fig.1). The formation of fairly strong acid sites was ascertained by the adsorption of NH₃ at a high temperature (420°C) (Table 5). This site was considered to be of Brønsted type. The CF₃Cl-treated Al₂O₃ also promoted the reactions of benzene with CF₃COCF₃, CF₃CHO, and other CF₃ -containing compounds (Fig.5 and Table 7).

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Syntheses of perfluoroanthraquinone and novel aminoperfluoroantraquinones were investigated. One-step reaction between tetrachlorophthalic anhydride and potassium fluoride in an autoclave at 300°C afforded a mixture of perfluoroanthraquinone (F₈AQ), chloroheptafluoroanthraquinone (F₇ClAQ), and dichlorohexafluoroanthraquinone (F₆ClAQ). It was more conveniently prepared from the reaction in a Pyrex glass ware at 370°C under atmospheric nitrogen followed by subsequent sublimation. Pure F₈AQ was revealed to be obtained by thorough fluorination of the above mixture of F, AQ, F₇AQCl, and F₆Cl₂AQ with spray-dried potassium fluoride at 150°C in sulfolane.
Amination of F₈AQ by ammonia in tol uene afforded 1-aminoperfluoroanthraquinone and 2-aminoperfluoroanthraquinone (product ratio; 92: 8 at 110°C and 29: 71 at -35°C). Reaction of F₈AQ in liquid ammonia at -50°C led to a formation of 2, 6-diaminoperfluoroanthraquinone as a sole product.

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As a part of synthetic studies for the multifunctional carbon compounds, some α-fluoro-α-(arylthio)acetate derivatives [6a∼c] were prepared via two routes.
Reaction of the potassium salts [3a, b] of nitroacetates [1a, b] with arenesulfenyl chlorides gave the trifunctional carbon compounds [4a∼c] in excellent yields. The esters [4a∼c] were easily converted to the corresponding potassium salts [5a∼c], which were fluorinated with perchloryl fluoride to produce the fluorine-containing tetrafunctional carbon compounds [6a∼c] in moderate yields. The fluoro derivatives [6b, c] were also prepared b y reaction of the potassium salts [8a, b] of fluoronitroacetic esters [7a, b] with arenesulfenyl chlorides in good yields.
The novel trifunctional [4a∼c] and tetrafunctional [6a∼c] carbon compounds obtained here are not yet known despite their structural simplicity. The fluorinated compounds [6a∼-c] seem to be potent candidates for serving as building blocks for synthesizing fluorinecontaining organic compounds.

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Reaction of elemental fluorine with the uracil ring systems in acetic acid proceeds via 5, 6-difluoro adducts (two cis-isomers), which were converted to four isomer adducts by subsequent solvolysis. Time course adducts were traced by ¹⁹F-NMR, but in the case of the cytosine ring systems, the adducts were not detected.
The adducts of uridine were changed to stable 6 -alkoxy forms and then separated.5fluorouracil [1F], 5-fluorouridine [3F], and 2', 3'-O-isopropylidene-5'-deoxy-5-fluorouridine [12F] were obtained in good yield by fluorination in hydrofluoric acid for [1F] and in acetic acid for [3F] and [12F], respectively, followed by treatment with hydrofluoric acid or an amine. Protected uridines were used as starting materials for [3F] and [12F].
5-Fluorocytosine [2F] and 5-fluorocytidine [4F] were also obtained in good yield u sing hydrogen fluoride and acetic acid-hydrogen fluoride mixture, respectively, as a solvent for the fluorination.

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In order to extend a utility of glycosyl fluorides as glycosylating agents, 2, 3, 5-tri-ObenzylD-ribofuranosyl fluoride [2] was prepared, and ribofuranosylations using [2] were examined.
The treatment of 2, 3, 5-tri-O-benzyl-D-ribofuranose [1] with 2.5 mol equivalents of hexafluoropropene-diethylamine adduct (Ishikawa reagent) in CH₂Cl₂ under N₂ atmosphere at room temperature for 4 h gave a-anomer [2α] and β-anomer [2β] pp of [2] in 21.4%and 63.8%nyields, respectively.
Both the reactions of [2β] and [2α] with isopropenyl trimethylsilyl ether [3] in the presence of BF₃⋅OEt₂ (0.05 equiv. ) gave stereoselectively (2, 3, 5-tri-O-benzyl-a-D-ribofuranosyl)acetone (4, 7-anhydro-5, 6, 8-tri-O-benzyl-1, 3-dideoxy-D-α-D-tro-2-octulose) [4a] in 94.6 % and 89% yields, respectively, together with traces of the corresponding β-anomer [4β] (see Tables 1 and 3). The treatments of [2β] with [1] and with 2, 3, 5-tri-O-benzyl-1-O-trimethylsilyl-β-D-ribofuranose [6] in the presence of BF₃⋅OEt₂ (0.1 and 0.01mol equiv., respectively) gave stereoselectively 2, 2', 3, 3', 5, 5'-hexa-O-benzyl (β-D-ribofuraosyl β-D-ribofuranoside) [5β] in 71% and 54% yields, respectively.
Those aspects of the stereoselectivity indicate an ex cellent utility of glycosyl fluorides as synthetic intermediates.

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Fluorinated α-oxoketene dithioacetals [3] were synthesized in moderate yields by the Lewis acid-promoted reaction of a variety of ketene dithioacetals [1] with hexafluoropropene (HFP)-amine adduct [1a] and/or [1b], derived from morpholine or diethylamine. The use of morpholine adduct gave more satisfactory results than that of diethylamine adduct. Among the Lewis acids employed, boron trifluoride-diethyl ether complex was the most effective for the reaction. The present reaction is strongly subject to steric hindrance caused by the alkyl group on the olefinic carbon atom in [2].

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Reactions of pentafluorophenyltrimethylsilane [1] with bis(2, 2'-bipyridine)copper(II)fluoride [2] were examined under various conditions. (Table 1) The reactions gave pentafluorobenzene [3] along with decafluorobiphenyl[4]
The addition of benzaldehyde into the reaction mixture did not differ the results, giving no adduct of benzaldehyde. The addition of iodobenzene and copper powder yielded pentafluorobiphenyl [5] in addition to [3] while no [4] was produced at all. Without copper powder the reaction afforded the mixture of [3], [4], Cali and [5]. The choice of solvents affected the selectivity of products. These products were conceivably produced under mild conditions via pentafluorophenylcopper(II) [6] and -(I) [8] as illustrated in Scheme 1.

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Reaction of 2, 3, 4, 5-tetrafluoro-1-nitrobenzene [4] with N-(ethoxycarbonyl)piperazine in aqueous ethanol gave 4-(4-ethoxycarbonyl-1-piperazinyl)-2, 3, 5-trifluoro-1-nitrobenzene [5] in 89% yield, which could be quantitatively converted into its 2-cyclopropylamino derivative [6]. Malonate [7] prepared from [6] and diethyl ethoxymethylenemalonate in 73% yield, was cyclized in the reaction with acetic anhydride and conc. sulfuric acid, accompanying elimination of the nitro group, to give [8] in 41% yield. Saponification of [8] gave quinolonecarboxylic acid [3] which possesses potent antibacterial activity both in vivo and in vitro, in 92% yield.

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