The anionic ring-opening polymerization of 3-ethyl-3-hydroxymethyloxetane (EHMO) was examined using t-BuOK as a base in the presence of 18-crown-6-ether in NMP at 180℃ for 3h, affording corresponding hyperbranched polyether poly(EHMO) containing an oxetanyl group and many hydoxyl groups as terminal groups. The synthesis of poly(EHMO) derivative [poly(EHMO)-AC] with acetyl groups was examined and its cationic copolymerization with 1,4-bis[(3-ethyl-3- oxetanyl)methoxy]benzene (BEOMB) was performed. As the result, the corresponding soluble hyperbranched polyether poly[poly(EHMO)-AC-co-BEOMB](M_n = 14,300, M_w/M_n = 2.28) could be obtained. Furthermore, poly[poly(EHMO)-AC co-BEOMB] derivative with pendant methacryloyl groups {poly[poly(EHMO)- co-BEOMB)-MA} was synthesized and its physical property and photo-chemical cross-linking property were examined.

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Lignin in non-edible woody biomass is a natural aromatic compound containing phenolic structure, and the effective use of lignin is expected as an alternative to petroleum-derived thermosetting resins. Utilizing the hydrothermal treatment of Japanese cedar powder in acetone/water (1:1) solution, low molecular lignin and crystalline cellulose were efficiently isolated in high yields. The obtained lignin showed good melting and curing properties, and a melamine decorative sheet with the lignin revealed practical flexural strength and boiling resistance. From these results, it is expected lignin will be utilized to various practical applications as plant-derived thermosetting resin materials near future.

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The didodecyl ammonium amphiphile, which contains trileucine as a structural part, formed a flexible film, when its chloroform solution was spread onto a silicon-coated paper and was air-dried. On the other hand, the air-dried cast film of the tetraleucine-containing amphiphile was extremely brittle. However, the brittle film turned to a flexible film by incubation at 70℃ for 1－3 hours. Not only the thermal treatment but also hydraulic press of xerogel produced a flexible film of the tetraleucine-containing amphiphile. For example, tensile stress of the cast film of the tetraleucine-containing amphiphile increased to 6.1 MPa by 3h-incubation at 70℃, whereas the tensile stress of the pressed film increased to 3.5 MPa by hydraulic press of xerogel at 9000 N/cm². The tri- or tetraleucine-containing amphiphiles initially formed a β-sheet structure, which stacked by a fastener-like action between the side chains of leucines within the different β-sheets (Leucine fastener). Leucine fastener brings flexibility, because a peptide-containing amphiphile except for origoleucine-containing amphiphiles did not form a flexible film. The increase of tensile stress should be also derived from Leucine fastener. Thermal treatment and the hydraulic press should promote the interlock between the side chains of leucines, and improve the mechanical strength of the films.

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Acrylate esters having different molecular weight of the polyethylene glycol units were blended with diallyl phthalate (DAP) resin to improve the fracture toughness and the adhesive properties. These blends were cured with dicumyl peroxide. By modification with acrylate esters, the fracture toughness, the T-peel adhesive strength and the lap shear adhesive strength to copper were improved. In particular, the fracture toughness and the adhesive strength were greatly improved when the DAP resin was modified with the acrylate esters having the large molecular weight of a polyethylene glycol unit, or with blending ratio of acrylate acid ester was larger. It is thought that the reason for this result is that flexibility was given by the introduction of the polyethylene glycol unit; as a result, an internal stress of the adhesive layer occurring in a curing process was relaxed. The DAP resin modified with acrylate esters showed a sequential-IPN structure when the acrylate ester having the small molecular weight of the polyethylene glycol unit was blended and blending ratio of acrylate esters having the large molecular weight was small. While, the DAP resin modified with acrylate esters showed a phase-separated IPN structure when it was blended 20wt% or more acrylate ester having the large molecular weight of the polyethylene glycol unit.

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Modified bismaleimide (BMI) with amine and epoxy resin containing allyl group and triazine ring (MADG, DAMG) indicated several advantages over using bisphenol-A type epoxy resin. For example, it had higher thermal resistance and lower thermal expansion. Moreover, this modified maleimide resin was prepared as a molding material for the purpose of development of next generation power devices for high heat resistant semiconductor encapsulation material. This molding material showed excellent thermal resistance and flame resistance without flame retardant. In this result, modified BMI with DAMG prove higher performance than conventional epoxy-phenol curing system for high thermal resistance molding materials.

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We had developed a novel material design method (weak conditioned combinatorial linear programming method). By defining solution area as a function of combination index, the optimum formulations are acquired. This optimization can be done by newly developed user-friendly software. This system is not applicable to complex properties and time series properties. For the development of adhesives, precise control of complex properties and time series properties are important. We tried to extend the system to complex properties and time series properties. The method is applicable to the design of adhesives which have complex properties.

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This review explained about methods using hydrogen peroxide to convert allyl ether to glycidyl ether and about obtained epoxy compounds. It was difficult to synthesize the allyl ether with halogen free condition, but efficient systems are developed recently by a transition metal catalyst. There are many examples of epoxidation using zeolite catalyst, but it is necessary to use the tungsten catalysts which can react under bilayer of the organic aqueous layer. About aromatic glycidyl ether, the obtained epoxy compounds have few differences in properties except the chlorine content. But in the case of aliphatic glycidyl ether, because there are many by-products in the epichlorohydrin method, they are totally different resin systems. Especially thermal resistance of aliphatic polyvalent glycidyl ethers are very high, so future development is expected.

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