Stage 1 and 2 potassium-graphite intercalation compounds (GICs) were allowed to react with unsaturated hydrocarbons. After contact with isoprene, styrene or 1,3-butadiene, K-GICs expanded slowly along the c-axis direction. Unsaturated hydrocarbons were introduced into the interlayer spacing of GICs and polymerized progressively. The polymerization is considered to be initiated by the radical-anions of the negatively charged graphite layer of K-GICs. Rubidium-GIC expanded slowly in a similar manner described above. In the case of cesium-GIC, isoprene was polymerized in the similar manner, whereas the reactivities of styrene and 1,3-butadiene were low. The different reactivities are explained on the basis of the activity of polymerization initiators. The degree of charge-transfer from alkali metal to graphite layer in the GIC of K or Rb was higher than that of Cs, which resulted in the higher reactivities of K- and Rb-GICs as a polymerization initiator. The reactivities of monomers for polymerization were in the following order: isoprene > 1,3-butadiene > styrene, which was the reverse order of the reactivities recognized in the conventional polymerization. Isoprene and styrene were polymerized in the interlayer of K-GIC in the presence of organic solvent. Isoprene was introduced into the interlayer, whereupon both aromatic and aliphatic solvents were incorporated into polyisoprene and polymerized. On the other hand, the polymerization of styrene in the interlayer of graphite was accompanied by the incorporation of aromatic solvents, but was not accompanied by the incorporation of aliphatic solvents. This is explained on the basis of the affinity of monomer and graphite layer for solvent. The novel carbon material obtained by a heat treatment of the product from the reaction of K-GIC with isoprene is also discussed.

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Polysilazanes HPZ1 and HPZ2 were synthesized by the ammonolysis of chloro(N,N-diethylamino)silane and bis(N,N-diethylamino)silane, respectively. Hydropolysilazanes, which were mainly composed of [H₂Si(NH)] units with a molecular weight of 1000 (M_w) were unstable for self-condensation reaction in tetrahydrofuran (THF) solvent. The self-condensation of HPZ1 and HPZ2 was retarded by silylation of terminal groups with chloro(trimethyl)silane or by dilution with the solvent such as THF and ether. On the other hand, soluble hydropolysilazanes with very high molecular weight (M_w of 85000 (HPZ1) and 45000 (HPZ2)) were produced by aging 35 wt% and 45 wt% THF solutions of polysilazanes at 20 °C, respectively.

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A solid phase extraction method for concentration of tin, and a new determination method for tin by reversed-phase high performance liquid chromatography (RP-HPLC) were described.
Amberlite XAD-7 resin coated with N-benzoyl-N-phenylhydroxylamine (BPHA) was prepared, and applied to the preconcentration of trace tin from aqueous solution. Tin was quantitatively adsorbed on the resin coated with reagent (BPHA/XAD resin) from 0.25 mol dm⁻³ hydrochloric acid solution by the batch method. After collection, tin adsorbed on the BPHA/XAD resin as tin-BPHA chelate was eluted easily by shaking with 0.5 mol dm⁻³ sulfuric acid-ethanol (1 : 1, v/v) mixture. This collection and elution method was applied to the RP-HPLC determination of trace tin. 2-(5-Nitro-2-pyridylazo)-5-[N-propyl-N-(3-sulfopropyl)amino] phenol (Nitro-PAPS) was used as a precolumn chelating agent for the reversed-phase liquid chromatographic determination of tin. Tin(IV) chelate was eluted on an ODS column with ethanol-water (60 : 40) mixture containing 1.0 mol dm⁻³ acetic acid, 0.01 mol dm⁻³ TBA⁺Br⁻ and 10⁻⁶ mol dm⁻³ EDTA as mobile phase, and then determinated with a UV-VIS detector. The calibration curve was linear over 0–8.0 ng cm⁻³ at 0.002 absorbance unit full scale and at 580 nm. The relative standard deviation for 4.0 ng cm⁻³ at three determinations was estimated to be 1.8%. The detection limit for tin was 0.58 ng cm⁻³ (3σ). Moreover, tin could be measured sensitively and selectively by combining BPHA/XAD resin solid phase extraction with HPLC method. After concentration of tin from 500 cm³ sample solution with the BPHA/XAD resin solid extraction method, the detection limit of the proposed method was 0.03 ng cm⁻³ (3σ). The proposed method was applied to the determination of trace amounts of tin in water samples.

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Electroreduction of alkylaminophosphonium salt has been utilized for the simple and safe preparation of the iminophosphorane without the use of the organic azide or dihalophosphorus compounds. An equimolar amount of electricity was applied to give one electron reduction products, from which hydrogen atom at alpha position was cleaved giving iminophosphorane and phosphonium ylide. Under the presence of aldehyde in this system, the reaction products were isolated and identified to elucidate the reaction paths involved. The onium salt with electron donating methyl group it gave only iminophosphorane quantitatively. On the other hand, the onium salt with electron withdrawing groups such as carbonyl groups yielded only phosphonium ylide quantitatively. In case of the onium salt with benzyl group, the mixed products from both Wittig and Aza-Wittig reactions were obtained.

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Pyrolysis of four coal liquefaction residues and their solvent extracts was carried out by a thermobalance. Weight losses by pyrolysis are relating to the yields of solvent extracts. Weight loss of Illinois No. 6 coal liquefaction residue was the largest among the four coal liquefaction residues since the fraction of the light volatile matter in both oil + asphaltene and preasphaltene was larger than that of other three residues. Weight loss of Wandoan coal liquefaction residue was the smallest due to the large amount of extraction residue. From kinetic analysis, it was found that activation energies for pyrolysis of coal liquefaction residues were lower than the mean values of coals. This is because distillation of the relatively light volatile matter is dominant for the residues. Activation energy increased at smaller heating rate since cross-linking reactions and condensation were promoted. Weight loss curves calculated with the activation energies and frequency factors obtained from experiments agreed well with the experimental ones. In pyrolysis of the coal liquefaction residue, the weight loss was large at relatively low temperature region compared to that of coal and most fractions of the volatiles can be extracted by solvents. Therefore, it is considered to be one of the effective utilizations of coal liquefaction residues to gasify the extraction residue after the solvent extraction.

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We conducted a basic experiment for the purpose of developing polymerized urushi that has a natural drying property in a low humidity environment, and examined the hardening process of the coating film with time as the urushi liquid dried by the enzymic oxidization using laccase in a constant temperature and humidity chamber (URUSHI MURO).
We postulated that the auto-oxidation of the side chain easily occurs in the urushi liquid due to the enzymic polymerization based on the change in the infrared absorption spectra during the drying process and anti-oxidation property of raw and sugurome urushi.
And, as a result, the change in the progress time of the drying property and degree of polymerization of the urushi coating film and liquid thin phase were measured. The molecular weight distribution of the urushiol in the time that naturally dries in a low humidity environment was admitted that the monomer component decreased to 27% or less.
From that it was found out possibility that the polymerized urushi that naturally dries in a low humidity environment can be obtained by stirring with additional moisture raw urushi in the reaction vessel of shallow bottom and decreasing urushiol monomer.

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In order to investigate the degradation of polychlorinated biphenyl degradation of its model compound 4-chlorobiphenyl (4-CB) with potassium carbonate in supercritical water in the presence or absence of copper(II) oxide was investigated. The reactions were carried out using two sorts of autoclaves made of sus 316 or Hastelloy X. The autoclaves were pressurized at 4–1 MPa at room temperature and heated to 500–570 °C to give the pressure of the mixture at 35–38 MPa. It was revealed that 4-CB was completely decomposed and that most of chlorine atoms were converted to potassium chloride. A gas mixture of benzene, toluene, and methane was obtained at the total yield of 10% and 4-biphenylol was obtained in the yield of 5–33% depending on the reaction conditions. Carbon skeleton of 4-CB was converted to CO₂ or HCO₃⁻ in the yield of 6–24% depending on the reaction conditions. Effect of addition of copper(II) oxide on the reaction was investigated to show that addition of copper(II) oxide brought about the increase of the yields of hydrocarbons, especially the yield of benzene at 500 °C. In addition to above stated products, water soluble and easily decomposable compounds were formed by the reactions in the present study.

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