Syntheses and biodegradation of aliphatic polyesters were studied. Polymers synthesized were copolyesters of L-lactide with lactones, copolyesters derived from γ-butyrolactone (BL), polyesters having alcoholic OH group, and copoly (ester/ether)s of oxiranes with lactones. γ-Butyrolactone copolymers were obtained by transesterification reaction, and the maximum BL content was around 30%. Polyesters having alcoholic OH group were prepared by the polyaddition of aliphatic diglycidyl ester compounds with several aliphatic dicarboxylic acids. The alcoholic OH group is susceptible to acylation. To develop biodegradable functional polymers, polyesters having alcoholic OH group as a side chain were found to be essential. Biodegradation was mainly evaluated by enzymatic hydrolysis concerned with the chemical structure. Hydrolysis was influenced by copolymer composition, lengths of methylene chain in the backbone, and substituents. The biodegradability shows the maximum at a certain composition depending on the ester content, the randomness, and crystallinity. The methyl side group in the polymer chain suppresses the degradation. The copolymers having long methylene chains (n = 3–5) have high biodegradability because of flexibility of the polymer chain. Hydrophilicity promotes biodegradability. Ester group in a side chain was found to be more biodegradable compared to that in main chain.

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On the adsorption of acid dye, Orange II, to goat hair, the effects of benzyl alcohol, glycine and hydroxy carboxylic acid in the medium of dye were studied quantitatively under various conditions of pH and temperature.
In the case of no benzyl alcohol, ΔS’s were negative and ΔH’s were in the region −25 – −100 kJ mol⁻¹. These results suggested that the dye might bind to the protein of goat hair with hydrogen bonds or ionic bonds. The ΔH’s shift more negative in the cases using glycolic acid and lactic acid than in the case using phosphoric acid. In the case of glycine, the goat hair adsorbed more dye in the lower pH medium, in which H₃N⁺–CH₂–COOH presented more than H₃N⁺–CH₂–COO⁻. Addition of benzyl alcohol with glycolic acid in the medium of dye made both ΔH and ΔS positive. Penetration of benzyl alcohol into the goat hair enlarged the surface area for the adsorption of dye. Thereby, the velocity and the amount of adsorption sites increased as compared with the case of no benzyl alcohol. On the other hand, the equilibrium constant decreased due to blocking the bond formation of dye to goat hair. Penetration of benzyl alcohol into the goat hair made difficult to speculate our results by a simple mechanism on the adsorption of dye according to Langmuir adsorption isotherm.

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Three-way catalystic performances of Pd catalyst supported on Ni-aluminate was superior than those supported on other supports. Adsorption and reduction properties of Ni-aluminate were investigated. The surface Ni²⁺ sites in Ni-aluminate were shown to act the adsorption sites of NO under both oxidative and reductive conditions. Under reductive conditions, in particular the Ni²⁺ sites cropped out abundantly resulting in a great increase in the quantity of NO adsorption. Ni-aluminate had higher resistance to the reduction with H₂, allowing to be reduced at 800 °C and, after the reduction, Ni-aluminate nearly recovered its previous state through a reverse process of re-oxidation. The reduction with H₂ was enhanced by the presence of supported Pd; Partial reduction occurred at about 400 °C, and the reduction peaks on the high temperature region shifted by about 50 °C. As confirmed from the activity test by using a model gas mixture (C₃H₆–NO–O₂), the Ni-aluminate supported Pd catalyst was more efficient in light-off activity and NO_x conversion activity under both stoichiometric and rich atmosphere than the Pd catalyst supported on γ-Al₂O₃. Based on these results, the excellent catalytic activity of the Ni-aluminate supported Pd catalyst is considered to show up through a mechanism in which the Ni-aluminate provides the adsorption sites for NO and transfer the adsorbed NO species to the catalytic reaction sites of Pd.

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Iridium catalyst supported on MFI-type metallosilicate with activation treatment in 10% H₂O–N₂ at 700 °C was prepared and its catalytic activity for the selective reduction of NO_x with hydrocarbons under oxgen rich conditions was investigated. The primary objective is the development of a catalyst system which reduce NO_x and the emission of hydrocarbons at a wide temperature range. The two stage catalysts with activated iridium catalyst and Pt–Rh/Al₂O₃ (Three-way catalyst), were prepared and showed NO_x reduction activity at a wide temperature range of 250–500 °C. Hydrocarbons were completely removed at higher temperatures than 300 °C. This system revealed high NO_x reduction activity both a lean and stoichiometry atmosphere, and showed superior transient NO_x reduction activity from lean to a stoichiometry atmosphere. The activated iridium catalyst showed a maximum NO_x conversion of 70% at 400 °C in the actual exhaust gas of a lean burn gasoline engine. It is inferred that the activated iridium catalyst had sufficient NO_x reduction activity and durability after aging treatment of a lean atmosphere at 660 °C and a rich atmosphere at 800 °C for a lean burn gasoline engine.

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Copper catalysts supported on MFI-type metallosilicate were prepared and their activities for selective oxidation of NH₃ were examined. Among the catalysts tested in this study, copper catalysts supported on MFI-type metallosilicate showed the highest activity. This catalyst selectively converted NH₃ to N₂ at 250–400 °C in the presence of excess oxygen.
The characterization of acidity and the effect of copper content revealed that active site of the catalyst in selective oxidation of NH₃ was the copper supported on the strong acidic site of metallosilicate. From NH₃–TPD, NH₃–O₂ pulse reaction and FT-IR measurements, amino groups formed on the catalyst surface were found to be intermediates of the NH₃ selective oxidation. The following mechanism for the selective oxidation of NH₃ was suggested; NH₃ is first adsorbed on the Brønsted acid site of metallosilicate and then converted to NH₄⁺. Secondly, dinitrogen group intermediate is formed by the oxidative dehydration of NH₄⁺. Finally, dinitrogen group intermediate is dehydrated oxidatively to N₂.

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The poly(vinyl chloride) (PVC) combustion has several problems, such as the damage of firebricks in the incinerator or additional risk by fire, because the hydrochloric acid (HCl) is generated by thermal decomposition of PVC.
It has been already known that the generation of HCl under the incineration of PVC can be controlled at lower level by means of mixing calcium carbonate (CaCO₃) and lithium carbonate (Li₂CO₃) into PVC. In this study, PVC resin samples were prepared with CaCO₃ or/and Li₂CO₃, which were surface-treated and controlled in size, in order to find out optimum compositions of the trap agents for capturing HCl under the incineration. Various chemicals containing iron have been known to accelerate the thermal decomposition of PVC resin. PVC resin samples mixed with FeO(OH) were also prepared and the capturing effect of HCl under the incineration of samples was investigated.
The capturing effect of HCl with both CaCO₃ and Li₂CO₃ was found superior to those with only single compound, CaCO₃ or Li₂CO₃. The sample with CaCO₃ : Li₂CO₃ = 3 : 1 (mole ratio) resulted in the highest capturing effect of HCl in this experiment. Furthermore, the samples mixed with a small amount of FeO(OH) were found to be efficacious for the capturing effect of HCl.

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Change of strength by heat treatment of laminated composite prepared from Kevlar cloth and furfuryl alcohol resin (furan resin) was studied by bending test below 600 °C. The laminated composite containing 39% fiber by volume showed almost the same value of bending strength as the matrix furan resin, and the effect of fiber cloth was recognized in the heat treatment temperature range from 200 to 500 °C. The laminated composite showed its own feature on the load vs. deflection curve. That is, a sudden flexural fracture did not occur below 400 °C as shown in Fig. 8c. On the heat-treated samples, the relationship, σ ∝ ρⁿ was recognized between the bending strength (σ) and the bulk density (ρ). Also, a linear relation was obtained, when the results were plotted with bending strength (σ_||) as abscissa against elastic modulus (E_||) as ordinate, but no linear relation could not be observed by plotting of E_⊥ and σ_⊥.

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Reaction of glycerol (116 mg, 1.3 mmol) with benzoyl chloride (177 mg, 1.3 mmol) in a mixture of pyridine (2 mL) and chloroform (5 mL) at 0 °C for 30 min under aerobic conditions gave the title water-soluble compound, 1-O-benzoylglycerol (1) (107 mg, 0.5 mmol) in 42% isolated yield. Structure of the product 1 was established on the basis of the spectroscopic data [UV, IR, ¹H- and ¹³C-NMR (including its ¹H–¹³C COSY), and FAB-MS]. Furthermore, effect of 1-O-benzoylglycerol (1) on the formation of the fruit body of Tokiirohiratake (Pleuroutus salmoneostramineus L. Vass.) was investigated, indicating that 1 promotes the effect.

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