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We have developed a flame-retardant polycarbonate resin whose flame retardancy is greatly enhanced by adding fly ash (a by-product from thermal power plants). Fly ash with comparatively small average particle sizes (

The flame retardancy and heat resistance of a phenol-biphenylene-type epoxy resin compound, which forms a self-extinguishing network structure, were increased by the inclusion of a benzoguanamine-modified phenol biphenylene resin. The benzoguanamine-modified phenol biphenylene resin contains a benzoguanamine unit to release non-flammable nitrogen substances during ignition and to increase the resin's reactivity toward epoxy resins, and biphenylene units to keep the resin's thermal degradation and water resistance. The addition of the benzoguanamine-modified phenol biphenylene resin in the epoxy resin compound improved the epoxy resin compound's flame retardancy and heat resistance, and also increased its glass transition temperature while maintaining its water resistance and mechanical properties. Copyright © 2003 John Wiley & Sons, Ltd.

Thermal plasma reduction of a SiO 2 –Al 2 O 3 mixture for metal production was investigated. The understanding of the reaction mechanism would be applied to metal recovery from coal ash. Thermal equilibrium and free energy of formation of the reaction systems were estimated to predict the evaporated species and to evaluate the predominant reactions. Atomic hydrogen plays an important role in the reduction of the SiO 2 –Al 2 O 3 mixture. Argon and argon–hydrogen plasma jets were used for the treatment of the SiO 2 –Al 2 O 3 mixture with various compositions. The argon plasma produces gaseous silicon and SiO from the SiO 2 –Al 2 O 3 mixture, though the recovered amount was very little, while Al 2 O 3 has not been reduced. The argon–hydrogen plasma produces mainly gaseous silicon with some additions of gaseous SiO and aluminum. Both of the argon and the argon–hydrogen plasmas produce the silicon component collected as the fumes having the purity of 98–99% from the SiO 2 –Al 2 O 3 mixture.

The impact strength of cellulose diacetate (CDA) bonded with a modified cardanol (3-pentadecylphenoxy acetic acid: PAA) was greatly improved up to 9 kJ/m2 by adding a relatively small amount of modified silicones while suppressing a decrease in bending strength. In our recent research, this thermoplastic resin (PAA-bonded CDA) exhibited high rigidity, glass transition temperature, and water resistance. However, its impact strength was insufficient for use in durable products. Therefore, silicones modified with polyether, amino, and epoxy groups were investigated as possible ways to improve the impact strength. The results show that adding polyether-modified silicone (polyether silicone) with moderate polarity relative to PAA-bonded CDA resulted in shearing deformation greatly enhances its impact strength while maintaining other properties, including glass transition temperature (Tg), water resistance, and thermoplasticity. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40366.

Impact strength of a modified cardanol-bonded cellulose thermoplastic resin was greatly improved by using a small amount of olefin resins. As we showed, this thermoplastic resin (3-pentadecylphenoxy acetic acid (PAA)-bonded cellulose diacetate (CDA): PAA-bonded CDA) exhibited high practical properties such as bending strength, heat resistance, and water resistance. However, its impact strength was insufficient for use in durable products. We improved the impact strength of PAA-bonded CDA by adding hydrophobic olefin resins, such as polyethylene or polypropylene, while maintaining good bending strength and breaking strain. Furthermore, the application of olefin resins also increased water resistance and fluidity. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 39829.

Permselective separation between water and water-soluble organics was investigated up to high concentration levels through crosslinked and metal complexed membranes of hybrid Schiff-base derivatives of poly(allylamine), which were prepared by the reaction between pyridine-2-carboxaldehyde (P) and salicyl aldehyde (S) with varying ratios of P/S. The complexed membranes had strong hydrophilic character and showed an increased flux and high permselective separation for t-butanol and tetrahydrofuran at high concentrations. Correlations between the performance of the complexed membranes and the physicochemical parameters, especially the solubility parameters, of alcohols and aprotic solutes were studied and discussed. It was found that a membrane with a higher P/S value tended to reject the aprotic solute with a smaller solubility parameter, while other physical properties of the alcohols also effected the alcohol separation.

We developed a heterogeneous process with low energy consumption to synthesize novel high-strength and heat-resistant cellulose-based bioplastics: cellulose esters bonded with a short chain component (acetic acid) and a long one (3-pentadecylphenoxy acetic acid; PAA), which is a derivative of cardanol, extracted from cashew nut shells. Although we recently showed that PAA-bonded cellulose acetates (cardanol-bonded cellulose resins) exhibit highly practical properties for durable products, they were synthesized in a homogeneous process, which requires large quantities of poor solvents to isolate the resins. In the developed two-step heterogeneous process, the cardanol-bonded cellulose resins are produced without poor solvents. In the first step, cellulose is esterified with limited amounts of the long and short chain components using a selected reaction solvent and catalyst. The resultant intermediate products are adequately swollen in the solvent then efficiently recovered by filtration. In the second step, the short chain component is additionally bonded to attain good thermoplasticity of the final products, which are readily recovered only by distilling a solvent and the remaining short chain component. The solvent usage was reduced by approximately 90 % compared with a homogeneous process, which leads to a large reduction in energy. The produced cardanol-bonded cellulose resins exhibited higher thermoplasticity, elastic modulus, water resistivity, and close heat resistivity compared to that of a homogeneous process. Furthermore, the mechanical and thermal characteristics of the resins were greatly improved by adding a specific polyester, polybutylene succinate adipate, and glass fiber, reaching high-level target properties for durable products.