This investigation clarifies the relationship between the composition of unsaturated polyester compounds and the mold shrinkage or low-profile property, which substantially controls the surface smoothness of SMC moldings.
The surface smoothness corresponded well to the mold shrinkage, to which the contribution of thermal shrinkage during cooling was larger than that of polymerization shrinkage during curing. The thermal shrinkage was found to be closely related to the microstructure of the moldings, consisting of a low-profile additive and an unsaturated polyester resin. There was less thermal shrinkage when the compound with a well compatible low-profile additives was molded under a lower molding pressure.

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The reaction of N-phenylmaleimide (PMI) with propargylphenylether (PPE) was investigated. PPE was converted to crα-chromene (PPE-C) by heating at 175°C, which was polymerized to oligomer by further heat treatment. As a main product, 1 : 2 adduct of PPE to PMI was generated under conditions with or without a catalyst (dicumyl peroxide or triphenyl phosphine) in the PPE/PMI reaction system. The reaction in the PPE-C/PMI system, which generated PPE-C/PMI oligomer as a main product, proceeded faster than that in the PPE/ PMI system. Without the catalyst, was also formed a considerable amount of the adduct, the molecular weight of which was 275.

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Three types of amino-terminated polyimide oligomers were synthesized as the toughening modifiers of epoxy resin.
Epoxy/oligomer PI-A mixture had a homogeneous type phase diagram. The cured resin modified with oligomer PI-A showed homogeneous morphology, with a slight improvement in toughness.
However, epoxy/oligomer PI-Si (block copolymer composed of PI-A block and polydimethylsiloxane block) mixture had a UCST (upper critical solution temperature) type phase diagram. Epoxy/oligomer PI-F (the oligomer with bis (aminophenoxyphenyl) hexafluoropropane structure) mixture also had the UCST type phase diagram.
The cured resin modified with oligomer PI-Si showed co-continuous phase separated morphology, with 8-9 times as much toughness as that of parent resin.
On the other hand, the cured resin modified with oligomer PI-F had spherical domains of the epoxy-rich dispersed phase in the oligomer-rich continuous phase. The toughness of this system also increased markedly.
The observations with a scanning electron microscopy showed that the oligomer-rich' phase (the minor component-30wt%) formed continuous phase in each cured resin, resulting in producing excellent toughness.

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Due to various donor acceptor interactions among functional groups of epoxy oligomers, curing agents and reaction products the bulk of reacting mixture possesses very nonhomogeneous structure. However the kinetic description of such reactions for many epoxy-aromatic amine systems turnes out to be unexpectedly simple. This contradiction is usually explained in terms of “compensation mechanism”, although an understanding of how does this mechanism really work is unsufficient.
New quantitative data on the inter-and intramolecular H-bonding in epoxy-amine systems, as well as on the effects of H-bonding on reaction abilities of reacting functional groups are presented and discussed in this review.

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Poly-p-vinylphenol is a versatile material with new applications in accordance with technical advancement. This review describes recent developments, including the application fields of thermosetting resins such as high performance printed circuit board, and anticorrosive coating. Another important application commercialized is chrome-free metal finishing. The most interesting and promising field is photoresist for micro-fabrication of 64 Mbit DRAMs.

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Polyurethane (PUR) coatings have widely been used in various application fields such as automotive coating, wood coating, and anticorrosion coating, due to their excellent performance on appearance, sovent/chemical resistance, durability, etc.
Two pack PUR coatings are situated as an industrial standard in spite of their limited pot life. On the other hand, one pack PUR coating with blocked isocyanates, which possess unlimited pot life, are gradually becoming more important in a production-line coating.
This article demonstrates the feature of PUR coatings, and focuses on the reactivity of dissociation or deblocking of the blocked isocyanates, and on that of subsequent crosslinking. It also describes their technically important applications, including water-borne and powder coatings.

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