We intented to develope the novel high performance rubber through the development of the technology by the improvement and modification of existing regular polymer, especially fixing our eyes upon the improvement of the interaction between polymer and filler. As the result, we could obtain the novel rubbers with iminium ion on the molecular chain ends. This developed modified rubber had an excellent rebound resilience and showed the sup erior properties for all season tire rubber materials. And in the process of the development of this chemically modified new rubber we also developed high vinyl polybutadiene rubber with about 70% of vinyl bond content which had mainly short side chain structure. This rubber showed the good balance of both properties, high wet skid resistance and low rolling resistance, which properties have seen required for the save-energy tire rubber materials, though the balance of these properties had been considered very difficult to achieve.
We studied the mechanism showing very high rebound resilience of chemically modified new rubber and the visco-elastic mechanism of high vinyl polybutadiene rubber which makes the high wet skid resistance and low rolling resistance be wellbalanced. Consequently we found that the both mechanism were much influenced by the interaction between rubber and carbon black filler. By the application of both mechanism to the same rubber we could obtain the superior performance tire rubber with both features resulted from both mechanism. And also, it was observed that this chemically-modified new rubber could bring out the excellent composite by blending of this novel rubber with other polymers which have the interactivity, such as plastics.

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For the application of activated carbons as adsorbents for removal of urea in blood, adsorption properties of urea were examined in aqueous solution. The adsorptive activity or adsorptive capacity was found to be nearly constant for most kinds of commercial products of activated carbon (0.13-0.15 g of urea per g of activated carbon) (Table 1). The activity was enhanced by oxidation with conc. HNO₃. The enhanced activity was, however, reduced by heat-treatment at higher temperatures; it decreased linearly with temperature, and became to half after heat-treatment at 800°C. On the other hand, the activity of non-oxidized activated carbon was not changed by heat-treatment up to 900°C (Fig.2). As compared to the non-oxidized sample, the conc. HNO₃-treated sample showed stronger solid acidity (Fig.4), and evolved much more amounts of CO₂ during heat-treatment in N2 atmosphere at tempera. tures lower than 400°C (Fig.3). The results of urea adsorption carried out in Ringer solution showed that the activity of the oxidized sample was somewhat suppressed by coexistence of alkaline metal ions, although that of the non-oxidized sample was not affected (Table 3). These facts suggested that the active sites for the urea adsorption on the conc. HNO₃-treated sample was dicarboxylic groups on the surface, while those on the non-oxidized sample might be lactone or related groups on the surface.

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To evaluate the catalytic activity of binuclear manganese(III) complexes, binuclear manganese(III) complexes with 3-salicylideneamino-1-propanol were synthesized. The oxidation of tetralin and the decomposition of 1-tetralyl hydroperoxide catalyzed by it were studied. The oxidation of tetralin catalyzed by it in MeOH exhibited low catalytic activity but 1tetralyl hydroperoxide with it decomposed under moderate conditions (30°C). These result suggest that the binuclear manganese(III) complexes were more effectivie for the decomposition of hydroperoxide than the activation of molecular oxygen. The effect of solvent was examined. The rate of 1-tetralyl hydroperoxide decomposition in many alcohols increased in the following order, MeOH <EtOH <n-PrOH <n-BuOH. In chlorobenzene-MeOH mixtures, the rate increased with increasing the concentration of chlorobenzene. It is assumed that the binuclear manganese(III) complexes form inner-share complex with the peroxide and then the decomposition of peroxide proceeds. The rate of 1-tetralyl hydroperoxide decomposition was retarded by the formation of hydrogen-bonding between MeOH and 1-tetralyl hydroperoxide.

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The reaction of aluminum hydroxide [Al(OH)₃] with diphosphorus pentaoxide [P₂O₅(H-, - and O'-form)] has been studied to clarify the conditions of formation of various Oaluminum phosphates and the role of hydroxyl group contained in Al(OH)₃.
(1) The species of aluminum phosphate and their amou nts largely depended on the heating temperature, heating time and the molar ratio (R) of P₂O₅ to A1(OH)₃. Aluminum orthophosphate [A1PO₄ (berlinite and cristobalite form)] and metaphosphate [Al(PO₃)₃ (A-form)]were formed at R=1/2. Triphosphate [A1H₂P₃O₁₀ (I-form)] and Al(PO₃)₃ (A- and B-form)were mainly produced at R=3/2. The predominant formation of A1(PO₃)₃ (A-, B- and Eform)was found in the reaction of R=3.
(2) Of three kinds of P₂O₅, H-form P₂O₅ had the highest reactivity with Al(OH)₃ and the reactivity of O'-form P₂O₅ was higher than that of O-form P₂O₅. These results were in good agreement with the tendency of hydrolysis of these three forms of P₂O₅.
(3) The hydroxide ions in Al(OH)₃ are very important to form aluminum phosphate by the reaction of aluminum hydroxide with diphosphorus pentaoxide.

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Fraipontite ((Zn_3-xAl_x)(Si_2-xAl_x)(OH)₄), a kind of 1: 1 type clay minerals was synthesized by coprecipitation of SiO₂, Al₂O₃ and ZnO components in the aqueous solutions, and by hydrothermal reaction. Simultaneous mixing of three solutions (AlC1₃-ZnCl₂, SiO₂-NaOH, Al₂O₃-NaOH solution) was essential to get fraipontite with monophase. But it s crystallite size was very small (Fig.1-A). Fraipontite with large crystallite size was obtained by hydrothermal reaction under mild conditions of 160°C and 3 h, by the use of metal oxides as starting materials and ammonium salt as a mineralizer (Fig.1-B). The ammonium salt accelerated the dissolution of ZnO and gave high selectivity to produce fraipontite (Table 1). The conversion of ZnO was also affected by specific surface area of silica (Fig.2). When diatomaceous earth was used as sillica source and reaction time was 20 h, the crystallite size of fraipontite became larger than that of using noncrystalline silica powder (Fig.4). Study of Synthetic Clay Minerals. I.

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The color change of calcichrome aqueous solution caused by methyl glycol chitosan (MGCh)has been studied spectrophotometrically at pH 6.80. The color of 30 μM calcichrome solution changed to blue violet from red violet by adding 2.3 x 10^-4N MGCh. The spectrum of this solution was little affected by the temperature change. Zephiramine showed spectrum change very similar to MGCh. In the presence of NaCl, the spectrum of calcichrome at 80°C was similar to the one caused by MGCh, while at 20°C, where calcichrome was presumed to be in an associated form, a spectrum quite different from the case of MGCh was obtained. The color change of calcichrome with MGCh seems not to arise from the dimerization of the dye but due to the ion-pair formation.

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Gas chromatography with a flame photometric detector (GC-FPD) provides a simple method for the determination of dibutyltin (DBT) and tributyltin (TBT) compounds leached from self-polishing antifouling paint into seawater. These compounds as their chlorides were extracted into toluene and hydrogenated to dibutyltin hydride (DBTH) and tributyltin hydride (TBTH) by sodium borohydride, afterwards analysed by GC-FPD equipped with a 610nm interference filter to monitor the SnH molecular emission. GC conditions were as follows: a fused silica capillary column; HiCap-CBP 1-W 25-300 (25 m ×0.53 mm i. d., df =3.0νm), column temp; 70°C(1 min)-10°Cfmin-200°C, injection temp; 250°C, detector temp; 300°C, carrier gas; nitrogen (1.0 kg/cm²), detector; FPD. The detection 'limits of this method were.05 ng for DBTC and 0.05 ng for TBTC. The recoveries of DBTC (104 ppb) and TBTC 0(110ppb) from seawater were 92.3% and 111.7%, respectively. From this work, it was found that the leaching rates of copper, DBT and TBT from self-polishing antifouling paint after 10 months of immersion at Hiroshima Bay were obtained to be 8.7-14.8, 0.42-1.02 and 1.87-3.70 νg/cm²/d, respectively. Studies on the Determination of Trace Amounts of Organotin Compounds in Seawater and the Behavior of Their Compounds in Marine Environment. IV.

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A highly sensitive method for the amperometric determination of chloride ion was developed by flow injection analysis utilizing the silver iodate substitution column. The increase of iodate ion concentration, produced by the substitution reaction of silver iodate with chloride ion, was monitered by measuring its reduction current with platinum electrode held at +0.3 V (vs. a silver tubing) and a silver tubing electrode. Mixed solution of sulfuric acid (0.002mol.dm^-3) and methanol (60%) was pumped at a rate of 0.9 cm³.min^-1, and hydrogen bro mide solution (0.8 mol.dm^-3) at a rate of 0.54 cm³.min^-1. Sample solution (20 μl) was injected into methanolic carrier solution at an interval of 2 min. The column packed with poly(vinyl chloride) resin (0.2-0.5 mm grain) including 63% silver iodate was used for the substitution reaction. The suitable concentration of chloride ion was less than 3 ppm. Analytical results of chloride ion (1-3 ppm) in river water by the proposed method showed good agreement with those of an ion chromatographic method. Concomitant compounds such as calcium ion, magnesium ion, sulfate ion, nitrate ion etc) in river water did not interfere with the determination.

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Electrochemical reactions of carbonyl compounds on platinum electrodes were carried out in acetonitrile, in the presence of excess ethanethiol. The carbonyl group of polycyclic aromatic ketones such as anthraquinone was reduced to yield the corresponding aromatic hydrocarbons. Carbonyl groups of condensed aromatic heterocyclic ketones were transformed into ethylthio groups with concomitant reduction. Simple aromatic and aliphatic ketones and aldehydes were readily converted to the corresponding dithio acetals under similar conditions.

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The title compounds (2) J were obtained in moderate yields from the reaction of 2, 4-disubstituted 6-chloro-1, 3, 5-triazines with potassium or copper( I ) cyanide in dipolar aprotic solvents such as DMF and HMPA. Similar treatment of 2, 4-dialkoxy-6-chloro-1, 3, 5-triazine with potassium cyanide, however, resulted in the formation of trialkyl isocyanurate (3); a mechanism involving decomposition of cyanotriazine initially formed is suggested for the formation of ( 3 ).
The reactions of cyanotriazine (2 a) with some nucleophiles including amine, alcohol, and azide ion are also described.

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A variety of 2-(phenyl- and alkyl-thio)maleimides were prepared by elimination of hydrogen halides from corresponding 2-halo-2-(thio-substituted)succinimides, which were obtained from 2-(thio-substituted)succinimides and halogen. Then, 2-(thio-substituted)3-halomaleimides were synthesized by elimination of hydrogen halides from 2, 3-dihalo-2(thio-substituted)maleimides prepared by the addition of halogen to 2-(thio-sub s iituted)maleimidesf We have screened for antimicrobial activity of these compounds, and found that 2-phenylthioN-methylmaleimide had good effectiveness against fungi, yeast, and bacteria. Especially, this material showed an excellent activity against bacteria among tested microorganisms.

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Porous glass powders (CPG) prepared by spinodal phase separation, and silica gel showed IR spectra (Figs.3 and 4) typical of so called isolated silanol hydroxyl groups on glass surface, when they were dehydrated by heating in dessicated air stream. Porous glass (SPG) prepared from volcanic sand as silicon source, which contains alminium up to 15% as Al₂O₃ (Table 2), adsorbed water more quickly than CPG (Fig.8), and it was fairly difficult to get simplified surface structure uniquely consisting of silanol hydroxyl groups, without any extraction of aluminium (Figs.2 and 6).
Surface density of am inoalkyl groups on the surface of porous glasses, either of CPG or of SPG which was dehydrated and followed by chemical modification with (aminoalkyl)trimethoxysilane, was estimated according to the method of Gisin who had used it for aminomethylated polystyrene in Merrifield's method of solid-phase peptide synthesis. The surface densities of amino groups were about 2 μmol.m^-2 for both CPG and SPG as shown in Fig.10and 11. The value corresponds to 1/3 of the density of silanol hydroxyl groups, 7-9 μmol.m^-2, estimated from the data of water elimination measurements of porous glasses (Tab le 4)by assuming the elimination of a water molecule from every two hydroxyl groups.

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The extraction of gallium from Bayer solution with 7-[1-(2, 2, 4, 4-tetramethyl pentyl)-2-propenyl]-8-quinolinol (KELEX) in kerosene as extraction agent has been examined In the excess of gallium and aluminium ions over KELEX, 1 mol of these metal ions coordinated with 3 moles of KELEX. The selective extraction coefficient (K_??_) was 112, but aluminium ions were extracted three to eighteen times as much as gallium ions because of the existing of high concentration of aluminium ions, Over gallium ions in Bayer solution. The gallium extractive ability of\ KELEX was lowered because of the deterioration of KELEX in Bayer solution exposed to the air. The deterioration rate coefficient (k) was derived as follows:
k=11.67 e^-1955/T h^-1
The addition of a, a-dialkyl-substituted fatty acids or 1-decanol as an auxiliary agent to the extraction agent was effected for the elevation of the extraction rate of gallium or the separation rate of Bayer solution layer and extraction agent layer.

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The Ohya-ishi powder contains about 65% by weight of clinoptilolite, a kind of zeolites. Taking the mineral composition of the Ohya-ishi, we have so far studied the application of Ohya-ishi as raw materials for the chemical industry, for example, an adsorbent, etc. In this report, we made a comparative study of chemical characteristics of clin optilolite contained in the natural zeolites of various origins as the main component. As reference sample, we used natural zeolites produced in the Itaya district in the Yamagata prefecture and in the Futatsui district in the Akita prefecture and also used synthetic zeolites of high purity and simple structure as a comparative sample. The surface characteristics of chemically tre ated samples were analyzed by the adsorption procedure using aqueous solutions containing adsorbing materials such as Methylene Blue and ammonium ion used widely in the studies on the clay minerals. The following points have been found:
( 1 ) Clinoptilolite contained in Ohya-is hi is characterstically poor in the ch6mical stability as compared with other natural zeolites.
( 2 ) As we have already poin ted out in the previous report, Ohya-ishi has very small specific surface area, in spite of containing the large amount of zeolite having large specific surface area. The results are attributed to the constituent minerals of Ohya-ishi and their existing states in an agglomerate.
( 3 ) The N., gas fa ils to diffuse into the inside of pores in the zeolite structure of Ohyaishi and the specific surface area is smaller than the treated samples.
( 4 ) By an aqueous hydrochloric acid treatment, the const ituent minerals that block the inlet to the zeolite structure to inhibit the diffusion of N₂ gas are dispersed and defloculated. So, the N₂ gas easily diffused into the pores and obtained a relatively large specific surface area values.
( 5 ) From the change in the adsorbability of Methylene Blue, we presumed that the cons tituent minerals that inhibit the diffusion of N₂ gas are smectite clay minerals contained in Ohya-ishi.
( 6 ) Smectite clay minerals are dispersed and deflocculated by hydrochloric acid treatment, so shape-selectivity of Ohya-ishi is destroyed and changes in the surface characteristics by dealumination occurrs, and the change in the coverage of (NH₄⁺/H₂O) ratio occurred and the adsorbability of NH₄⁺ decreased.
( 7 ) Using this shape- selectivity of Ohya-ishi, it is effective to remove the cations contained in wastewater. Study on the Chemical Utilization of Ohya-ishi Powder. V.429

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When a solution of benzopinacol (1) and DMSO-SbC15 (1: 1) complex (Complex A) (1: 1ratio) in nitromethane was allowed to stand at room temperature for 24 h, benzopinacolone ( 2 ) was obtained in quantitative yield. In this reaction, tetraphenylethylene oxide (3) was detected as an intermediate. The reaction seems to proceed according to the following stoichiometry.
2 Ph₂C-CPh₂ DMSO-SbCI₅→2 Ph₃C-CPh + SbOCI₃+ DMSO + H₂O +2HC1
The pinacol rearrangement of [1] over with O.15mol eequivalent of DMSO-TICI₄(1: 1)complex (Complex B) proceeded quantitatively. In this case, both theoxygen atom and the chlorine atom sseem to participate in the formation of [2]as an oxidizing agent. Study of Synthesis Using Metallic Complex. X.

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A dielectric model expression was introduced to evaluate a magnitude of electric field imposed to the liquid /crystalline phases when an external electric field is applied to a (polymer)/(liquid crystal) composite film. It was suggested from the dielectric model calculation that the large electric field is effectively imposed to the liquid crystalline phases by using the matrix polymer with the greater magnitude of dielectric constant and electric conductivity. It was revealed that the electro-optical response speed can be remarkably improved in a wide frequency range by using the matrix polymer with the greater magnitude of dielectric constant and electric conductivity.

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