Novel quinolinium salts, such as N-benzyl-, N-(a-phenylbenzyl)-, N-(1-naphthylmethyl)-, and N-cin-namy1-3-bromoquinolinium hexafluoroantimonates were synthesized by the reaction of 3-bromoquinoline and the corresponding bromides, followed by anion exchange with KSbF₆. These quinolinium salts could polymerize epoxy monomers at about the same temperature as previously reported N-benzyl-2-cyanopyridinium hexafluoroantimonate. A combination of these quinolinium salts and peroxides could polymerize epoxy monomers at lower temperatures than salts alone. These salts could initiate photo-radical polymerization as well as photo-cationic polymerization, both of which were accelerated by the addition of an aromatic compound (2-ethyl-9, 10-methoxyanthracene) and aromatic ketones (benzophenone, 2, 2-dimethoxy-2-phenylacetophenone) as photosensitizers.

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Three types of epoxy resins were decomposed by a 4 mol/1 or 6 mol/1 nitric acid solution at 80°C for chemical recycling. A bisphenol F type epoxy resin cured with diaminodiphenylmethane (DDM) was decomposed by immersion for 400 hours in the 4 mol/1-or 80 hours in the 6mol/1-solution. A tetraglycidyl-diaminodiphenylmethane (TGDDM) type epoxy resin cured with diaminodiphenylsulfone (DDS) was decomposed for 50 hours in the 4 mol/1-or 15 hours in the 6 mol/1-solution. Decomposed products which were extracted with ethylacetate from the solution were clarified to be produced by C-N bond breakage and nitration. Generally, epoxy resins cured with acid anhydrides have good resistance to acid solutions. Since TGDDM contains C-N bonds in the network structure, it seemed to be decomposed by the nitric acid solution. The TGDDM resin cured with methyl endic anhydride could be indeed decomposed for 250 hours in the 4 mol/1-or 80 hours in the 6 mol/1-solution. Thus, the recycling method presented in this study can be applied to epoxy resins cured with acid anhydrides. If the objective is repolymerization of recovered compouds, bisphenol F type epoxy resins are suitable and the nitric acid concentration of 4 mol/1 is recommendable. If the objective is waste disposal, on the other hand, TGDDM resins cured with DDS and the 6 mol/1-solution are preferable.

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Polyurethane foam was decomposed by diethanolamine (DEA) in continuous decomposing apparatus and recycled as epoxy resin. In this study, effects of amount of DEA used in the decomposing process and mixture ratio of decomposed product to epoxy resin on the properties of the recycled resin were investigated. It was found that, in the case of changing mixture ratio of decomposed product to epoxy resin, the recycled resin showed good mechanical and electrical properties at a peak of mixture ratio vs. glass transition temperature, depending on the amount of DEA in the decomposing process. In addition, the properties of these samples were equivalent to those of anhydride cured epoxy resin.

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Alloying of polybenzoxazine with polyimide was examined. Polymer alloy films were prepared by blending benzoxazine monomer with poly (amide acid), a precursor of polyimide, followed by film casting and the thermal treatment for ring-opening polymerization of benzoxazine and imidization. The resulting alloy films were made up of a semi-interpenetrating polymer network consisting of linear polyimide and crosslinked polybenzoxazine. AB-type co-crosslinked polymer alloy films were also obtained by the copolymerization of benzoxazine with polyimide containing phenolic hydroxyl as an activated aromatic group. Both types of polymer alloys were effective to improve the brittleness of polybenzoxazine and to increase its Tg and thermal degradation temperature. The semi-IPN formation was especially effective for toughening the polymers, while the AB-type crosslinked polymer network did for increasing Tg values.

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A magnetic field was applied to a mixture of grinding chips and an unsaturated polyester prepolymer in order to produce a conductive resin. The magnetized chips formed a network structure, contributing to developing the electrical conductivity of the cured product. Various magnetizing methods were evaluated, and it was found that the cured resin with highest conductivity could be obtained by the magnetizing method of inserting the prepolymer mixture in a solenoid coil and holding a magnetizing current until the gel point of the mixture. The magnetization using electrical magnets in contact with the curing mixture was also found to be effective, if the magnets were properly arranged and supplied with a specific range of electrical current.

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Polystyrene network gels have been used as the most popular polymer supports in solid-phase peptide synthesis, column chromatography, ion-exchange resins, polymer supports for catalysts, enzymes, etc. These functionalities are closely associated with diffusional behavior of solvents and probe molecules, intermolecular interactions between polymer chains and probe molecules, and also with structure and dynamics of polymer supports. Super-High-Field-Gradient NMR method is a very useful tool to study these fields. From such a situation, we introduce simple theory, analytical method and annual research especially polystyrene gel. Then diffusing time (time scale of measurement) in this method were discussed.

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