In this study, we report a novel method for selective synthesis of naphthylene ether trimers by condensation of 2,7-dihydroxynaphthalenes in the presence of neutral alkaline metal salt under acidic condition. We prepared an epoxy resin from the trimers and examined properties of the cured epoxy resin. As a result, the cured resin showed not only good physical thermostability, such as high glass transition temperature and low thermal expansion coefficient, but also good chemical thermostability like high thermal decomposition temperature. Additionally, low moisture absorption of the cured resin was also confirmed. From these results, the novel epoxy resin with naphthylene ether skeletons is considered to be suitable for advanced applications such as high-tech electronics parts.

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Poly(phenylene sulfide) (PPS) resins are known to show excellent heat resistance, chemical resistance, flame retardance, and mechanical property, and therefore, have been applied to various molding compound such as electric parts for automobile. On the other hand, the poor bonding ability with various adhesives and adhesive property with other materials are disadvantages of PPS resins. In this paper, we studied in the improvement in adhesive property of PPS resins by the addition of special epoxy resins, which were obtained by the glycidyl etherification of secondary hydroxyl groups of bisphenol A-type epoxy resins. As a result, the obtained PPS resin composition was found to show excellent mechanical and adhesive properties.

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Experimented to a condensation reaction of phenol and Anthracene-9-carbox aldehyde. It was confirmed that this is not a condensation reaction of phenol and aldehyde is generally known reaction. The resulting compound (BIP －ANT) was identified as bisphenol compounds having an anthracene structure in the main chain. If appropriate reaction conditions, it is possible to extract the intermediate had a hydroanthracene structure. BIP－ANT is a compound having a high refractive index and fluorescence. It was also confirmed to show a variety of reactivity due to the bisphenol structure. Polymers obtained from BIP－ANT was confirmed that has a high refractive index and high heat resistance.

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Indole based epoxy resin(INRE) was synthesized by the reaction of epichlorohydrin and indole oligomer which was obtained by polycondensation reaction of indole and paraformaldehyde. In order to evaluate the effect of indole structure on the thermal properties, o-cresol novolac type epoxy resin was used as reference. The cured polymer of INRE with phenol novolac showed glass transition temperature of 177.8℃ in DMA measurement which was comparable with 184.1℃ of the OCNE polymer, while showed lower storage modulus in the rubbery states. Moisture absorption was 0.15wt% lower than that of the OCNE polymer. This result might be attributed to the aromatic structure and lowering high polar ether moiety in the cured polymer compared with that derived from glycidyl ether.

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Although cyclic amidine compounds are strongly basic compounds and used as hardening accelerators for epoxy resins, little has been known as single-component initiators so far. In this research, curing behavior of epoxy resins were examined by using a cyclic amidine compound with active hydrogen, 1,4,5,6-tetrahydropyrimidine (THP). As a result, two-step exothermic reactions based on an addition of THP to the epoxide and the epoxy polymerization were observed. We might propose the following anionic polymerization mechanism; in the initiation reaction, a hydroxyl group should be formed by an addition of the THP to the epoxide. And subsequently, the deprotonation of the hydroxyl group by tertiary amino groups of the THP must be procedured, and the generated alkoxide induced an anionic polymerization of the epoxide.

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[in Japanese]

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