Solvothermal reactions are designated as the reactions which use high temperatures and/or high pressure solvents. It is possible to control the acid-base reaction rate, morphology and agglomeration of the products, i.e., wel1 dispersed nanoparticles with high crystallinity can be obtained by solvothermal reactions. Therefore, solvothermal reactions are expected to be used to generate environmentally friendly functional ceramic materials. Actually, various functional ceramic materials, such as high performance near infrared shielding materials, UV-shielding materials, automobile exhaust gas cleaning catalysts, etc. have been fabricated by solvothermal reactions.

View full abstract

High-performance bioplastics are indispensable for establishment of sustainable green society. However the conventional bioplastics were not distributed very widely due to the low thermomechanical performance and no specific functions. Here we propose new synthetic routes for high-performance bioplastics such as biopolyamides and biopolyimides. As for biopolyamides, a biomonomer itaconic acid （IA） is used, which is mass-produced by the fermentation of Aspergillus terreus, to form rigid N-substituted pyrrolidone ring in the polyamide backbone via salt-type monomers composed of diacidic IA and diamines. The polyamides show higher thermomechanical performance than those of conventional polyamides, and show solublility in water by ring-opening reaction of the pyrrolidone induced by landfill or ultraviolet-irradiation. Next we prepared one of the highest performance polyimides from microbial resources. We develop bioavailable aromatic diamines, which are photodimers of 4-aminocinnamic acid （4ACA） derived from geneticallymanipulated Escherichia coli, and polymerize it to form the corresponding polyimide films. The biopolyimide films show ultrahigh thermal resistance with T₁₀ values over 425℃ and no T_g values under 350℃, which is the highest value of all bioplastics reported thus far. The PI films also show high tensile strength, high Young's moduli, good cell compatibility, excellent transparency, and high refractive indices.

View full abstract

Enhancement of thermal conductivity along the out-of-plane direction in polyimide（PI）blend films containing silver nanoparticles（Ag-NP）, µm-sized pyramidal or needle-shaped ZnO, and cubed MgO particles has been extensively investigated. Microphase-separated structures with "vertical double percolation（VDP）" morphology were spontaneously formed in the PI blend films composed of sulfur- and fluorine-containing PIs, in which two phases were separately aligned along the out-of-plane direction, and ZnO and MgO particles were preferentially precipitated in the fluorine-containing PI phase. In particular, the PI blend films containing needle-shaped ZnO particles exhibited significant enhancement of thermal diffusivity along the out-of-plane direction even at lower filler contents, which indicate that the VDP structure with selective incorporation of anisotropic shaped inorganic particles functions as highly efficient thermal conductive pathway.

View full abstract

BMC（Bulk Molding Compounds）with glass fiber from waste FRP（Fiber Reinforced Plastics）derived glass fiber through depolymerization of unsaturated polyester under ambient pressures and general products were compared. It was found that the thickness of BMC made from waste FPRderived glass fibers were larger than general products and those of the glass fiber in BMC were around 0.4mm in length. Bending strength of BMC made from waste FRP-derived glass fibers were a little lower than those of the general products and it was confirmed that the BMC made from waste FPR-derived glass fibers included air-bubble void.

View full abstract

The necessity for energy saving has been pointed out since the Great East Japan Earthquake. In the manufacturing process of electronic ceramics, there are heat treatment processes, such as calcination and sintering, and temperature is also 1300℃ or more and is using many energies. We considered energy saving about the manufacturing process of electronic ceramics. Some techniques of leading to energy saving about the sintering process which is the highest temperature in a manufacturing process and has most energy consumed, use a small particles of raw material, use of a liquid phase method, and addition of sintering aid are described.
Furthermore, the low temperature sintering material containing many lead oxides is also described.

View full abstract