The present paper relates the study and development of high strength and high modulus aramid fiber, Technora. In general, aramid polymers composed of wholly aromatic polyamide present a good heat resistance. Particularly, para-type aramid polymers have rigid molecular skeletons which enhance the strength and modulus of polymer chain. However, it is not easy to shape these para-aramid polymers as a melt or to solve them in organic solvents. Therefore, the fiber formation technique becomes quite difficult. Our basic idea was to modify the rigid molecule to be soluble in an organic solvent. The first key technology was the introduction of a slightly flexible element into the rigid molecular structure. The second innovation was to improve the fiber strength by high temperature drawing. In principle, the chemical modification of this kind was not simple, because the flexible element often spoiled the rigid polymer structure. Various polymers were studied to meet the incompatible requirement. However, the following aramid copolymer showed excellent mechanical properties among others.
0c0C0 N ONH -(COG0H N -0-0-CFHN)n (average of in) / (average of n) = 50 / 50
In this molecular structure the meta-bonded ether plays an important role. It increases the solubility to organic solvents and yet preserves the rigid linearity of polymer chain. The polymerization condition and spinning and drawing conditions were o ptimized. In particular, the development of a novel drawing process was successful in the elevation of fiber strength. The drawing temperature was extremely high over 500 °C, which was not common for organic fiber productions. The obtained fiber strength was 3.4 GPa. This value is the highest among commercialized aramid fibers. Also, the fiber shows a strong resistance against chemicals, abrasion and fatigue.

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An advanced process for manufacturing acetal resins has been developed. First, a new technology for the production of highly concentra ted aqueous formaldehyde was developed by oxidizing methylal. Whereas the oxidation of methanol yields 1 mole of water per mole of formaldehyde, methylal oxidation gives only 1 mole of water for every 3moles of formaldehyde. Thus, industrially, the products of the methylal oxidation is more than 70% concentrated aqueous formaldehyde compared with 55% concentration from methanol oxidation.
Secondly, with the highly purified formaldehyde from the concentrated aqueous formaldehyde, an end-capped polymer can be obtained using acetic anhydride as a chain-transfer agent or an end-capping agent during polymerization.
Thirdly, the relatively high concentr ation of formaldehyde enhances the formation of 1, 3, 5-trioxane. Purified trioxane is copolymerized with ethylene oxide in the presence of an end-capping agent to get an end-capped polymer with high thermal stability.
Two new intermediates in the initiation reaction of the copolymer ization, 1, 3, 5, 7-tetraoxacyclononane (TOCN) and 1, 3, 5, 7, 10-pentaoxacyclododecane (POCD), were isolated and a new initiation mechanism was proposed.
Finally, the world's first acet al block copolymer was industrialized by the copolymerization of formaldhyde with lubricant functional polymer which has an active hydrogen atom. This acetal block copolymer exhibits excellent lubrication properties.

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The rate constants for the enantioselective hydrolysis of L- and D-isomers in racemic substrates were determined for the first time by use of the simplex method. The noteworthy aspects are as follows: (a) the rate constants and enantioselectivity for the hydrolysis of the racemic substrates catalyzed by the most active tripeptide N-benzyloxycarbonyl-L-phenylalanylL-histidyl-L-leucine (Z-PheHisLeu) having the a-helix structure agreed well with those for the hydrolysis of the enantiomer substrates with the same catalyst in the miceller systems; (b) the enantioselectivity for the hydrolysis of the racemic substrates by the dipeptide NbenzyloxycarbonylL-phenylalanyl-L-histidine (Z-PheHis) or the long-chained amino acid NtetradecanoylL-histidine (Myr-His) catalyst was fairly reduced as compared with that for the hydrolysis of enantiomeric substrates with the same catalyst in the miceller systems.

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A microcomputer-controlled instrument for measuring A-T isobars of monolayers was developed and isobars of a series of long-chain acid from myristic (C₁₄) to arachidic (C₂₀) were measured with this instrument. All isobars of the monolayers except that of arachidic acid exhibited first-order phase-transitions in the temperature range measured from the liquidcondensed to the liquid-expanded state with increasing temperature at constant surface pressures. The transition temperature increased about 10 °C with every increase of one carbon atom of alkyl chains. It also increased about 8 °Cwith every increase of surface pressure of 10 mNim. The dependence of the transition temperature on the carbon number of the long-chain acids did not show the so-called odd-even effect. The two-dimensional thermal expansivity of long-chain acid monolayers decreased gradually with increasing the carbon number of alkyl chains at a constant surface pressure.

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SMSI (Strong metal-support interaction) effects on several catalytic reactions over supported Rh and Pd catalysts were investigated.
Catalytic activities of typ ical structure-sensitive reactions such as hydrogenolysis of C₂H₆and cyclo-C₆1-1₁₂ were suppressed by 5 to 6 orders of magnitude by high-temperature reduction (HTR) (Fig.3), whereas a suppression is only by about 1 order of magnitude in a cycloC₆H₁₂ dehydrogenation as a structure-insensitive reaction (Fig.2). These behaviors are reconciled with a geometric effect due to the decoration of metal surface by a suboxide resulting from partial reduction of supports or additives.
Suppressions are not remarkable in a n NH₃ decomposition (0.6 orders of magnitude: Table 1, Fig.4), and hydrogenations of CO (Table 2, Fig.5), butyraldehyde and acetone (1 to 2orders of magnitude: Tables 3-5), where a promotion by ligand or electronic effect should be taken into account in addition to the geometric one.
Hydroformylation of C₂H₄ over Pd catalysts is an interesting catalysis, where its activity is clearly accelerated after HTR (Tables 6, 7). In this case, a great promotion by the ligand or electronic effect should exceed the suppressive effect by decoration.
SMSI does not always suppress the catalytic activities. I n this study, we found clear evidence for an acceleration effect of SMSI (Tables 8, 9).

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Reduction of NO with NH₃ was studied at ambient temperature over active carbon fibers (ACF_s) further activated with sulfuric acid. among ACF_s, pitch based one (OG-5 A) further activated at 400°C for 4 h showed the highest activity in a temperature range of 25-200°C. It is of value to point that this particular ACF maintained the activity for reduction of NO at 25°C in air of 100% humidity. Other ACF_s lost their activities almost completely under the above condition. Such prohibiting effects of humidity were reduced at higher reaction temperatures. The active sites for NH₃ and NO are briefly discussed based on the TPD analyses of oxygen containing groups on the ACF surface. The retardation by humidity is related to the hydrophobic nature of the ACF surface. Such a property may be governed by the size of carbon hexagonal plane as well as kinds and numbers of surface oxygen groups. Thus, the highest activity of pitch based ACF further activated at 400°C is qualitatively explained based on the adsorption amount of NH₃, activation ability for NO, and the hydrophobic nature.

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The formation of large-sized crystals of lead(II) sulfate precipitate was examined by using an optical microscope, a scanning electron microscope, X-ray powder diffraction method, energy dispersive X-ray analysis systems and a thermal analysis. The morphology of crystals formed in this experiment was compared with that previously formed in the stirring reaction.
Lead(11) sulfate was precipitated through the static reaction of the precipitation from homo geneous solution (PFHS) method on the reaction time (0.5-6.0 h), by using lead(II) nitrate (16.7 x 10-3 M) and sulfamic acid (16.7 x 10^-3 M-83.5 x 10^-3 M) aqueous solutions at 100 °C.
The thin layer plate of lozeng crystal which was smaller than 10 p m in the major a xis appeared at the beginning of reaction and at low concentration of sulfamic acid (16.7 x 10^-3M). With continuing precipitation reaction, the former crystal grew quickly longer than 200 pm, and then the shape of them was transformed from thin hexagonal plate longer than 250 pm to thick hexagonal plate longer than 300 gm.
At higher concentration of sulfamic acid and long reaction time, the growth steps of the crystals went through very rapidly, and finally, these crystals grew to rectangular octahedron crystal from 230 gm to larger than 300 pm by the crystal habit. And, these crystals were much larger than the crystal of 120 hem obtained by the stirring reaction in the major axis and the volume of particles. Besides, they were the single crystals and had smooth surfaces.

The strongest X-ray diffraction lines of the lattice planes of the precipitates obtained through almost all of the precipitation reaction appeared at (002) plane of the planar growth plane which was based on the selective orientation of crystal, and the appearance of such a plane did not change in spite of the increase in concentrations of sulfamic acid and reaction times.

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Homogeneous layered double hydroxide-cristobalite rock (LDH-Cb rock) composite materials were prepared by impregnating Mg²⁺ and Al³⁺ions into pores of the Cb rock in suspension state and by successively adding the suspension to Na₂CO₃ solution at the conditions of pH 10 and 60 °Cto hydrolyze these metal ions. The resulting solid products composed of Cb rock and Mg²⁺-Al³⁺-CO₃^2- system LDH were heated at 500°C for 1 h to make an effective composite adsorbent for both acidic and basic dyes. The composite adsorbents, which are compose d of Cb rock and magnesium-aluminium oxide solid solution as shown in Fig.5, indicated high adsorpability for Orange II and Methylene Blue. As seen in Figs.6 and 7, the Freundlich's adsorption isotherm formula can be applied in all cases. The adsorpability per unit weight of the whole composite adsorbent for Orange II was found to be slightly lower than that of the heat-treated LDH, while the adsorpability per unit weight of LDH in the composite adsorbent became 2 to 3 times that of the heattreated LDH as indicated in Table 1. This should be due to the high dispersion of LDH into the Cb rock. On the other hand, the adsorpability for Methylene Blue based on the negative charge surface of Cb rock in the composite adsorbent was found to decrease by compounding LDH, but the magnitude of the decrease was not much larger than that of the heat-treated heterogeneous LDH-Cbrock composite adsorbent prepared by the another method.

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The crystals of lithium hypochiorite were prepared by the hydrolysis of t-butyl hypochlorite. Lithium hypochlorite thus prepared contained LiClO₃ 2.7%, LiC1 5.1%, LiOH 3.1%, and H₂O(water of crystallization and adhesion) 14.7% as impurities. From DTA it was found that adhesive water wa s lost at 37 °C and the water of crystalization at 62 °Crespectively and the explosive exothermic reaction occurred at 143 °C (Fig.1). X-Ray powder diffraction experiments proved that the products decomposed at 143°C were LiC1 and LiClO₃ (Fig.2).
The experiments of the decomposition rate at 100 °C disclosed the following facts; particle size of crystals does not influence on the decomposition rate (Fig.3) decomposition rate under decrease pressure is slower than that under atmospheric pressure (Fig.4).
The decomposition rate of LiClO is slower than that of its monohydrat e LiClO; H₂0. The decomposition rate of LiClO is enhanced by the presence of LiCLO₃ (Fig.5).
The decomposition temperature of crystal of lithium hypochlorite was h igher than as compared with that in the case of sodium hypochlorite, thus the former has much high stability.
From the result of DTA, X-ray diffraction analysis, gas chromatography and chemical analysis, it was revealed that the decomposition reaction of lithium hypochlorite consisted of the main reaction (3LiClO→2LiCl+LiClO₃)and the 5, --10% subreaction(LiClO→LiCl+1/2 O₂).

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Tris[1-(p-substituted phenyl)-1, 3-butanedionato]chromiun(III) complexes, CrL₃ (L=p-XC₆H₄COCHCOCH₃, X = NO₂ C [1], COOH [2], COOCH₃ [3], Br[4], Cl[C5], H [6]NHCOCH₃[7], C₂H₅[8], CH₃[9], OCH₃[10], OH [11]), have been synthesized, and were separated into mer and fac isomers by column chromatography on alumina. The configuration and stability of these isomers obtained were investigated by the magnetic and spectral measurements. Each isomers of [1]-[11] have the high spin octahedral structure of d3 configuration in solid state and as well as in chloroform, pyridine and DMSO. The absorption bands due tovc=o+vo-o, Ring def.+vcr-o, vcv-o+vcr+vc-cH₃ and ⁴T_2g(F) ←⁴A_2g, (F), which were related to the bond between carbonyl oxygen and chromium(II), shifted to the higher frequency side with the increase of electron donation of the substituents. Therefore, the strength of Cr(III)-O bond and the stability of these complexes were found to increase in the orde r of [1]<[2]<[3]<[4]<[5]<[6]=[7]<[8]<[9]<[10]<[11]. The spectral parameters, 10 Dq and B, were 17.4 x 10³-48.0 x 10³ cm^-1and 510-610 cm^-1, respectively.

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Determination of T1 in water by inductively coupled plasma emission spectrometry after solvent extraction was investigated at T 1 II 190.86 nm. The spectral profile of the emission line of Ti showed two peaks at 190.855 and 190.867 nm. The reason of the profile split was concluded to be a superfine structure due to the nuclear spin. The spectral profiles obtained for aqueous solutions with 5 fig Tl/ml and 200 μglml each of diverse elements revealed that Mo, Ce, Ta, Os and W had emission lines close to the Tl 190.86 nm line, which were not stated in the conventional wavelength tabled. When Tl was extracted into 2, 6-dimety1-4heptanone (DIBK) after complexation with ammonium 1-pyrrolidinecarbodithioate (APDC)and hexahydro-1 H-azepinium hexahydro-1 H-azepine-1-carbodithioate (hexamethyleneammonium hexamethylenedithiocarbamate) (HMAHMDC), measurement at 190.855 nm was successful, although the 190.867 nm emission line suffered from the increase of background intensity presumably due to carbon in DIBK. With 160 ml of water sample and 8 m/ of DIBK, the detection limit (3σ) was 1.3 ngT1/m/ in original samples, and the calibration curve was linear up to 625 ng/m/. The relative standard deviation (n=10) including the solvent extraction process for 30 ngTlim/ was 5.4%. Among the diverse elements, Os(VIII) more than the concentration of Ti, and- W more than 40 times the concentration of T1 caused spectral interferences even after the solvent extraction. Since Os and W are usually rare in waters, the proposed method was successfully applied to the analysis of river, mine and hotspring waters. Some samples contained 15 ng/ml or more of T1.

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Cellulose diacetate in mixed solvents consisting mainly of dichloromethane-ethanol and mixed diluents, which contain ester and alcohol, was suspended in an aqueous solution of gelatine to form droplets. Dichloromethane-ethanol in the droplets was removed by evaporation to obtain cellulose diacetate beads containing the mixed diluents.
The beads thus obtained were saponified and the mixed diluen ts were removed subsequently to prepare porous cellulose beads. The porous cellulose beads obtained were classified in the 74-297 μm, 297-500 μm and 500-1700 pm bead size ranges. The permeability into the ir porous cellulose beads was determined by eluting water soluble materials such as poly (oxyethylene)through a column packed with the gels and the maximum values of the exclusion molecular weight were 2.8 x 106, 10⁶ x 10⁶, 1.5 x 10⁵, respectively.
The porosity of the gels could be controlled by type and amount of mixed diluents. This method is suitable for the preparation of porous cellulose large beads.

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In order to develope a new kinetic method for the determination of trace amo unts of copper 0: 0, the Cu(II)-catalyzed oxidation of such water-soluble thiols as cysteamine, L-cys teine, 2-mercaptoethanol and 2-mercaptopropionic acid has been examined in water or in a mixture of water and such aprotic solvents as N, N-dimethylformamide (DMF), dimethyl sulfoxide and acetonitrile. In this method, the decrease in the concentration of thiols was measured spectrophotometrically for the determination of Cu(II). The best sensitivity was achieved using 60% DMF solution as the reaction media and L-cysteine as water-soluble thiols. The calibration curve of Cu(II) was linear over the range 0-1.1 x10⁶ M and passed through the origin. The determination limit was reached down to 3.9 x 10^-8 M (2.5 ppb) for Cuan. The relative standard deviation of five succesive experiments was 1.8% at 1.7 x 10^-7 M of Cu (II). The selectivity achieved by the proposed method was highly excellent, since most of diverse ions tested were tolerated high ratios. The proposed method has been applied successfully to the determination of Cu(II) in waste water.

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In binaly mixed solvent systems (ethanol-benzene, ethanol-dioxane, and I5MF-methanol), amination kinetics of benzylchloride (BC) and chloromethylated polystyrene (CMPS) with s-butylamine was examined for, the purpose of elucidatiOn of solvent effect of alcohol on the reaction. According to Kondo-Tokura's theory on the reaction in binary mixed solvent system, the amination kinetics of BC was analyzed. In ethanol-benzene and ethanol-dioxane solvent systems, the dependence of the observed values of log km(k, : amination rate constant)and δEM, activation energy, on mole fraction of ethanol, x1, were in agreement with the calculated curves on the assumption that both the reactant and transition state are specifically solvated with ethanol (Type I). This result may be explained by that ethanol is hydrogenbonded to the amine, the reactant, and the leaving group (chloride ion) of which the polarity increases at the transition state.
In DMF-methanol system, the observed values of logkm and γEM, , were in agreement with the calculated curves on the assumption that the reactant is solvated with methanol and the trasition state is solvated with DMF (Type II). This may be explained by that methanol is hydrogen-bonded to the amine and the polar transition state is bonded to DMF by diroledipole association. The amination kinetics of CMPS, which was not measured over all the range, was similar to that of BC.

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The formation process of the cholesteric liquid crystal from isotropic phase was investigated by temperature-jump method for the solution of Poly(r-benzyl L-glutamate) (M v=1.5 x10⁵)in N. N-dimethylformamide. The process was compared with that from nematic state.
The solution at a volume fraction of 0.191 (v/v) was prepared in a cylindrical glass tube (thickness=2.0 mm, diameter=12.5 mm) sealed to prevent solvent evaporation and stored at 20-50°C (liquid crystal phase) for aging before examination. The solution was maintained at 125 °C (isotropic phase) for 20 min and quenched at each temperature (20, 30, 40, and 50°C). The solution was observed at successive time intervals with polarizing microscop y and light scattering under a controlled temperature. The time dependences of the 11, light scattering pattern and of the depolarized light intensity were obtained only in an early stage. The temperature dependence of the viscosity of the solution was measuared by the falling ball method.
From the above experimental results, the formation process was shown to occur in two steps as follows. ( 1) Generation of spherulitic structure abruptly after the solution was quenched from isotropic phase followed by the development of the birefringent phase over the whole solution within 1 minute. (2 ) Appearance of irregular cholesteric pitches within 40to 60 minutes. The succesive process significantly depended on cooling temperature. Above 30 °C, a small domain with homogeneous cholesteric structure appeared in a portion of irregular structure and continued to grow. The regular structure extended over all the solution. The times forming in equilibrium state were about 43, 4, and 3 days at 30, 40, and 50 °C respectively. On the other hand, at 20 °C, which was above the gel temperature by 5 °C, regular structure did not appear even after 48 days. t Liquid Crystalline structures of Poly(a-amino A cids). VII.

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Novel 2, 5-bis(substituted methylene)-2, 5-dihydrothiophenes such as 2, 5-bis[di(ethylthio)methylene]-2, 5-dihydrothiophene[1] and 2, 5-bis[cyano(ethylthio)methylene]-2, 5-dihydrothiophene [2] were successfully prepared. The first reduction potentials of [1], [2], and 2, 5-bis(dicyanomethylene)-2, 5-dihydrothiophene [3] were measured in cyclic voltammetry to know the electron-accepting character of each compound. The compounds of [1], [2], and [3] are not homopolymerizable with any initiators and also not copolymerizable with vinyl monomers except for an alternating copolymerization of [3] with styrene. The attempts of copolymerizations of [1], [2], and [3] with 7, 8-bis(butoxycarbonyl)-7, 8-dicyanoquinodimethane [10] as a highly conjugative comonomer failed and only the homopolymer of [10] was obtained, showing that these thiophene derivatives are as much lower in reactivity than [10].

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The sorption of various atmospheric alcohols such as methanol, ethanol, 1-propanol, 1butanol, and 1-hexanol into soil was studied to elucidate the influence of water content of soil. The linear relation between sorption amount and the sorption equilibrium concentration was obtained for all of these alcohols and also it was found that the sorption of alcohols followed Henry's law. The Henry's law constant of alcohols were minimized at water content of 20-30%. The existence of minimum point of Henry's law constant was explained on the basis of van der Waals force and dissolution of alcohols into water. It is estimated that the absorbed alcohols would be released from soil to the atmosphere when water content of soil come close to 20-30% because the Henry's law constant is minimized at this range. It was found that these phenomena were general tendencies of water soluble compounds.

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