Synopsis: Phenolic/organo-montmorillonite nanocomposites were prepared from phenol novolac, hexamethylenetetramine and montmorillonite (MMT) organized with phosphonium salt such as triphenylstearyl (PhStP), tris(hydroxyphenyl)undecanoic acid (HOPhUP), and trisdiphenyl ether undecanoic acid (PhOPhUP) by hot-roll kneading. Structure and properties of those nanocomposites were investigated. It was found that phenolic resin was intercalated between layers of these organomontmorillonite. The degree of dispersion of MMT in phenolic/PhStP－MMT nanocomposite was the best. On the other hand, there was some aggregation of MMT about 1μm diameter in phenolic/PhOPhUP－MMT nanocomposite. The mechanical strength of these composites was comparable to or tended to decrease with phenolic resin alone. However, heat resistance, low thermal expansion, and flame retardant of these composites were better than those of phenolic resin alone or phenolic/MMT organized with oleylbis(hydroxyethyl)methylammonium salt used as reference. In particular, phenolic/HOPhUP－MMT nanocomposite showed good heat resistance and flame retardant.

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Synopsis: A phenolic lignin (PL) was synthesized by the reaction between lignin and phenolic compound. Industrial use of PL has been desired as a new recycle process of wood-resources. Phenolic lignin cured epoxy resins (PL-cured) were prepared as curing agent for epoxy resin to investigate the properties As a result, PL-cured showed well-balanced thermal and mechanical properties compared with lignin cured epoxy resin (LG-cured) and with phenol novolac cured epoxy resin (Standard). Next, epoxidization of phenolic lignin was performed via a two-step reaction consist of ring-opening reaction and ring-closing reaction. An epoxidized phenolic lignin (EPL) was cured with phenol novolac to investigate their properties. Accordingly, it was revealed that EPL was possible to be applied as epoxy resins.

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Synopsis: 3,4-Epoxycyclohexyl methyl methacrylate (M100) was polymerized by atom transfer radical polymerization (ATRP) using an initiator bound to fluorinated polyhedral oligomeric silsesquioxane (R^f-POSS). The polymerization proceeded in a living fashion, providing tadpole shaped polymers with an “inorganic head” of R^f-POSS and an “organic tail” of well-defined poly(3,4-epoxycyclohexyl methyl methacrylate). A hybrid film composed of the tadpole shaped polymer, cycloaliphatic epoxy resin (CEL2021P) and cationic initiator (SI－100) was cured at 160℃ for 1 hour, and then analyzed by contact angle measurement, X-ray photoelectron spectroscopy. These analyses revealed that the R^f-POSS was preferentially populated at the air/polymer interface and the outermost layer of the film was almost completely covered by the R^f-POSS heads. This was mainly due to the low surface free energy and environmental stability of the R^f-POSS moiety. The surface structure of the hybrid film was immobilized by cross-linking of epoxy resins, and the surface property was optimized by the control of curing condition.

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Synopsis: A highly deuterated random novolac-type phenolic resin was prepared by polycondensation of deuterated phenol and formaldehyde using oxalic acid as an acid catalyst. The polymer conformation in THF at 40℃ was evaluated from the scaling exponent of Mark－Houwink－Sakurada equation, and the exponent of 0.26 was obtained for the deuterated phenolic resin. This value is close to our experimental value and the previously reported values for nondeuterated phenolic resins. This fact suggests that phenolic resins in THF behave like a compact spheres irrespective of deuteration.

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Synopsis: Dynamic Headspace Gas Chromatograph-Mass Spectrometry (DHSGC-MS) was used to detect and identify imidazole accelerators in cured epoxy resins. We measured the cured epoxy resin including isocyanate-modified imidazole accelerator by DHSGC-MS under various heating sample conditions, and as a result, both imidazole and isocyanate volatiles originating from the accelerator were detected and identified at the sample heating condition of 300℃/15min. This method was used to identify various imidazole accelerators and modified components in cured epoxy resins, as well as in copperclad laminates.

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Synopsis: Many network polymers, such as epoxy and urea resins, have been used as adhesives. In this review, physical chemistry of interface in adhesive bonding is introduced and the stability of interface is discussed from the view point of the interfacial free energy. In addition, it is reviewed that the chemical composition at the interface varies dynamically to minimize the free energy of interface and that the interfacial composition of adhesives can be controlled based on this principle.

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