In order to fabricate polymers bearing both reactive hydroxyl and other functional groups, we conducted radical polymerization of methacrylates bearing hydroxyurethane structures prepared from aminolysis of a methacrylatebearing a five-membered cyclic carbonate, and examined reactions of the resulting polymers. For the efficient synthesis aforementioned monomers, we optimized the reaction conditions, i. e., use of a trace excess amount of amines to the methacrylate bearing a five-membered cyclic carbonate at 0 ℃ in toluene, by which the undesired Michael addition to the double bonds was suppressed. The functional groups originating from the amines allow the polymers obtained from radical polymerizations of the methacrylate bearing hydroxyurethane structures to be soluble in various common organic solvents in spite of the high densities of the hydroxyl groups. The reactions of the resulting polymers with cyclic anhydrides in the presence of triethylamine and with 2-methacryloyloxyethyl isocyanate afforded polymers bearing carboxylate and methacryl groups, respectively. The polymer bearing methacrylate moieties in the side chains could be thermally networked. The reaction of the polymer with 4,4'-methylene bis(phenyl isocyanate) afforded a networked polymer.

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The organo-bentonites were prepared with an intercalation agent such as 10-carboxydecyltris (4-phenoxyphenyl) phosphoniumbromide which was synthesized and applied to epoxy nanocomposites. This organo-bentonite was dispersed in a mixture of diglycidyl ether of bisphenol F and acid anhydride, and the ternary mixtures were able to cure without any curing accelerator such as triphenylphosphine. The obtained epoxy/organo-bentonite composites were studied by dynamic mechanical analysis, thermo-mechanical analysis, and flame retardant test. We found that these composites containing small amount of organo-bentonite have high thermal and flame-retarding properties, and low constant of thermal expansion in comparison with those of unmodified epoxy resin. TEM micrographs showed that the clay particles could be well dispersed and exfoliated in the epoxy matrix.

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It is difficult to quantitatively analyze the chemical structure of network polymers that have strong cross-linked structures. Recently, solid-state NMR method attracts attention as the analysis techniques of solid compound with the advances of analytical instruments. We studied the cure degree and the cured chemical structures of random novolac and resol resins by CP/MAS NMR. The measuring method used typical CP/MAS of Solid-State NMR. As a result, it was suggested that the cure degree becomes higher with an increase in the amount of 1,3,5,7-tetraazatricyclo (3.3.1.1 (3,7)) decane that is hardener for novolac resins, and with increasing curing temperature for resol resins. In addition, the existence of an intermediate structure was confirmed for cured random novolac and resol resins.

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In enhanced and horizontal recycling of FRP, Fiber Reinforced Plastics, which are very difficult to be recycled, the separation and modification processes of styrene-fumaric acid copolymer (SFC) using 1-octanol were investigated. Almost 100% of the SFC was extracted with 1-octanol, and water residue in the SFC after extraction was 25wt%. The SFC extracted with 1-octanol was modified by 1-octanol with H₂SO₄ at 175 degree C for 17 hours. The modification was attained almost 100%. The modified SFC was mixed with a commercial low profile additive (LPA) to produce FRP sample board and tested. At 50% content of the modified SFC, the modified SFC showed almost equivalent performance to the commercial LPA. This suggests the possibility of “enhanced recycling” of FRP thermo-setting resin. The scale-up of this process was also investigated. Pilot plants of subcritical water hydrolysis and inorganic materials separation processes were designed and built. Pilot test using the pilot plants with a grinding pilot plant showed the performances which were almost more than 90% of that of bench plants. Bench plants of the SFC separation and modification processes were also designed and built. The bench-scale test showed the nearly 85% performance of beaker-scale test.

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The present work deals with the free-radical crosslinking copolymerization of liquid polybutadiene rubber (LBR) with allyl benzoate (ABz) in order to discuss further the preceding copolymerizations of acrylic monomers with liquid diene rubbers as internal olefinic multivinyl crosslinkers. The use of unconjugated ABz monomer in place of conjugated acrylic monomers led to a promoted gelation through a skewered crosslinking reaction of growing poly(ABz) radical with LBR because the reactivity of internal olefinic double bonds in LBR backbone is unconjugated-type and, therefore, they are facile to copolymerize with ABz compared to acrylic monomers.

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This paper reviews recent studies on cage type silsesquioxane (SSQ)/epoxy resin nano-composites for clarifying their advantages in various properties. Many kinds of cage type SSQs, which have various organic substitutional groups including epoxy ones, have been utilized for these nano-composites studies. Data of the nano-composites properties, such as glass transition temperature, storage modulus, impact strength, or thermal stability, etc., are cited from a dozen of literatures and plotted against the additive amount of SSQ in Figures for better understanding of the effectiveness of SSQ addition. These data show that the cage type SSQ/epoxy resin nano-composites have various notable features from the standpoint of practical use. Furthermore, possible applications of the nano-composites are investigated from the information based on published patents and commercially available formulation products. Many promising potential applications are found in electronic, optical, coating, and composites fields, while the high production cost is still a high barrier for the cage type SSQ/epoxy resin nano-composites to enter the actual market.

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Tannin gel (TG) with polyhydroxyphenyl groups was synthesized as an adsorbent for the hydrometallurgical recovery process of noble metals. It was further modified to enhance its adsorption performance by impregnating TG with SCN^–, which produces SCN^–-retaining tannin gel (SCN-TG). It was found that the adsorption mechanism of noble metal ions onto TG is a redox and Au(III) can be adsorbed selectively from the mixture with Pd(II) and Pt(IV) by difference in redox potential. SCN-TG adsorbs Pd(II) selectively in a highly acidic condition due to the great difference in kinetics and stability of metalligand complexation between Pd(II) and Pt(IV). After selective adsorption of Pd(II) under dark condition, the photosensitive Pt(IV)-SCN complexation can be employed to enhance the adsorbability of Pt(IV) on SCN-TG through light-irradiation. Consequently, it is suggested that the effective combination of the two adsorbents, TG and SCN-TG, according to metal species can make it feasible that each noble metal ion (Ag(I), Au(III), Pd(II) and Pt(IV)) is recovered selectively in sequence under acidic condition with high efficiency: Ag(I) in nitric acid media, Au(III) by redox potential higher than that of PGMs, Pd(II) by labile kinetics in complexation, and finally Pt(IV) recovery by light irradiation.

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