Thermosensitive copolymer beads containing pyridyl groups were prepared by suspension polymerization of 4-vinylpyridine (4VP), N-isopropylacrylamide (NIPAAm), and tetraethyleneglycol dimethacrylate (4G) dissolved in chloroform, in saturated Na₂SO₄ aqueous solution in the presence of surfactant and MgCO₃ as dispersant. Quaternized 4VP-NIPAAm-4G copolymer beads were obtained by the reaction of 4VP-NIPAAm-4G copolymer beads with alkyliodide. The 4VP-NIPAAm-4G copolymer beads had thrmosensitivity in water. The adsorption ability of the 4VP-NIPAAm-4G copolymer and the quaternized 4VP-NIPAAm-4G copolymers for surfactants, organic acids, food dyes, or Bisphenol-A was investigated under various conditions. It was found that 4VP-NIPAAm-4G and the quaternized copolymer beads had high adsorption ability for sodium dodecylbenzene sulfonate (SDBS) and Bisphenol-A (BPA).The adsorption of these compounds is mainly due to hydrophobic interaction between the copolymers and solutes.

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So as to control catalytic activity of H₂PtCl₆ toward the hydrosilylation process, polymers bearing various sulfide moieties were employed as an additive of the catalyst and their effect on the activity was evaluated. From the study on the hydrosilylation reaction of trimethylvinylsilane with triethylsilane at various temperatures, they were found to serve as a good retarded of the catalyst where the activity of Pt catalyst was depended upon the polymer structure. The curing reaction of silicone resin was also carried out in the presence of various polymers to observe the same tendency to the model reaction. That is, the combinations of H₂PtCl₆ and sulfide polymers were found to be an excellent latent catalyst for the hydrplilylation process. The curing temperature of silicone resin was controllable by the character and the concentration of the polymer.

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Phenolic resin-layered silicate nanocomposites were prepared from conventional phenol novolac, hexamethylenetetramine and organo-bentonite (MMT) modified with quaternary ammonium salt such as dodecylbis (2-hydroxyethyl) methylammonium (C12CH2OH), oleylbis (2-hydroxyethyl) methylammonium (C18CH2OH), and methyl-stearyl-benzylammonium (C18CH2Ph) by hot-roll kneading. At first, the conditions of hot-roll kneading were studied in order to intercalate phenol novolac into MMT. As a result, the compounds were found to show better silicate dispersion due to the suitable melt viscosity at the kneading temperature of 100-110°C. Secondly, the effects of hydrocarbon chain length and functional group of quaternary ammonium salt of MMT on properties of phenolic composites were studied. It was found that the extents of silicate dispersion of phenolic/C18CH2OH-MMT composite and phenolic/C18CH2Ph-MMT composite were larger than that of phenolic/C12CH2OH-MMT composite, and phenolic/C18CH2OH-MMT (3~5phr) composite had the best mechanical strength and heat resistance. For these results, following two reasons are considered : one is the proper melt viscosity of phenolic/C18CH2OH-MMT compound and phenolic/ Cl8CH2Ph-MMT compound, which facilitates the intercalation of phenol novolac into MMT, and the other the suitable hydrogen-bonding interaction between phenolic resin and hydroxyl groups of the organic modifier of Cl8CH2OH-MMT.

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Structure-property relationships in a set of Q8 silsesquioxane hybrid materials that cure through epoxy as well as hydrosilylation reactions were investigated. By using shorter epoxy chain lengths (DGEBA eq=180) in epoxy/Q8 silsesquioxane hybrid networks, the materials showed high heat resistance with the elimination of the glass transition temperature of the hybrid. In contrast, by using longer epoxy tether lengths (DGEBA eq=650) or brominated epoxies (Brominated DGEBA eq=400), glass transitions were observed. However, in return, the hybrid dielectric constants were much smaller than those obtained using the shorter tether epoxy hybrid systems. Copper clad laminates were fabricated by using epoxy/Q8 silsesquioxane hybrid systems and the board properties were measured. The board did not show any glass transition and offered a 94V-0 level of flame retardancy. The bromine flame retardant content of the board was half those of conventional epoxy resin boards (FR-4). These results are attributed to hybrid effect of the system, indicating that the Q8 silsesquioxane/epoxy hybrid materials can be a potential approach to realize high performance electric materials. Q8 silsesquioxane hybrid cured through hydrosilylation was subjected to transparency tests as well as UV (380nm) exposure tests. The hybrids showed high transparency even under exposure of short wavelength light, much higher than those of alicyclic epoxy resins. Besides that, the hybrid exhibited high UV exposure durability, hence the potential of the hybrid to be used in optical device applications was demonstrated. Based on a small angle X-ray diffraction study, it is suggested that the hybrid contains pore sizes much smaller than those observed with conventional epoxy resins.

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Bio-based polymeric materials from renewable resources are significantly important in industrial and economic viewpoints. Inexpensive triglyceride plant oils have been used for production of valuable resins. However, these oil-based polymeric materials do not show enough properties of rigidity and strength required for structural applications by themselves. This review deals with new bio-based polymers and composites from renewable natural oils. By selected combination of organic and inorganic additives, the properties of the oil-based polymers were significantly improved.

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This paper reviews recent studies on carbon nanotube (CNT) /epoxy resin composites. Many kinds of CNTs, epoxy resins, and curing agents have been used for preparing CNT composites. Major factors governing composites properties lie not only in the combination of CNT and epoxy resin formulation, but also in the dispersion state of CNT in epoxy resin matrix. Therefore, the description on procedures improving CNT dispersion, especially surface treatment and modification techniques for CNT, is allowed a large space in the review. Furthermore, the computer simulation or modeling study, which plays a key role in understanding CNT composites properties from the view point of molecular size, is also explained along with actual applications, mainly as sporting goods, of these nanocomposites.

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