Synthesis of diglycidyl 2, 6-naphthalenedicarboxylate (DE) from 2, 6-naphthalene-dicarboxylic acid, its curing with several curing agents, and properties of the cured products are described. Synthesis of DE was carried out by the reaction of 2, 6-naphthalene-dicarboxylic dichloride with glycidol (90% yield, m.p. 143-144°C). DE was mixed with one of the curing agents (0.6-1.6 equivalents), and the mixture was heated at a temperature above the melting point of DE (150-220°C) to give the corresponding cured products. The products cured with trimellitic anhydride (TMA) or diaminodiphenylmethane (DDM) as a curing agent had good toughness and Tgs. To estimate the effect of introducing naphthalene moiety into epoxy resins, the properties of the cured products from DE were compared under the same conditions with those from diglycidylterephthalate (TE) and from diglycidylether of bisphenol A (DGEBA). The glass transition temperature (Tg) of the cured products of DE/DDM system was 200°C, showing 20°C higher than that of TE/DDM or DGEBA/DDM. Further, Tg of DE/TMA was 214°C showing 10°C higher than that of TE/TMA or DGEBA/TMA. In summary, the cured products from DE were superior to those from DGEBA in the properties such as flexural strength, flexural modulus, and water absorption.

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The extrusion molding process is less progressed in thermostting resins compared with that in thermoplastics, due to difficulties in analizing a complex change in flow of the compounds in a heating cylinder : on their melting, simultaneously takes place partial crosslinking which gives us technical tasks to be studied.
The extrusion molding has an advantage of higher efficiency in industrial production than the injection molding. The technical developement in the extrusion of thermosetting resins has been performed since the latter half of 1970's, from the viewpoints of both hardware (molding machines & equipment) and software (molding materials). This, as a result, led several companies in the world to a success in commercializing the technology.
This article describes the development in the extrusion technique of thermosetting resins, the difference in the extrusion technology between thermoplastics and thermosets, and a practice in the phenolic pipe extrusion.

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This review describes the present techniques and problems on the surface treatment of filler particles with silane coupling agent for a particulate filled composite especially composed of epoxy resins and silica particles. Recently, it has been clarified that a structure of the treated silane coupling agents on the silica surface is a monolayer or a multilayer, although that is a network on the surface of glass fiber. A mechanical strength of the composites is improved by the surface treatment whereas their fracture toughness is not always improved. The novel method to directly evaluate an interfacial strength between a particle and a matrix was proposed recently.

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Rubbery network polymers can be realized where network polymers have low crosslink density and degree of molecular motion of polymer chains between crosslinks are very high. Typical physical properties of them are reversible very large deformation and very low modulus. They are based on entropy elasticity. In this short review, pulsed NMR studies of these materials focused on the degree of molecular motion will be introduced with several examples. They are characteristics of rubber elasticity from the view point of physics, change of molecular motion of rubber chains and crystallization under elongation, molecular motion of rubber chains in filler reinforced composites, molecular motion and phase transition of gels, physical properties of thermoplastic elastomers and molecular motion, and so on. In the last, physical properties of rubber bearings for seismic isolation will be mentioned as an interesting example of the extension of this kind of studies.

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