The lowest interfacial free energy (γ12) calculated by Fowkes' equation is considered to be one of the dominant factors so as to optimize adhesion at the interface. However, the view may not be reasonable since the lowest γ12 does not give the highest Dupre's work of adhesion (WA). In order to verify the reliability of the view, peel strength of the two kinds of pressure sensitive adhesives (PSA) to the several polyolefins including cycloolefin polymers was examined and plotted vs. the dispersion component of the surface free energy of the polyolefins (γ2d). If the view is universally reliable, peel strength must be the maximum when Y2d is equal to the dispersion component of the surface free energy of the PSA (γ1d) as well as Kitazaki's previous research. On the contrary, the obtained peel strength in our research did not show the maximum value when γ2d was equal to γ1d. According to our investigation, the lowest γ12 calculated by Fowkes' equation is not considered to be the optimum condition for adhesion at the interface.

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Effects of C-NBR and CPP contents on morphologies and properties of cured epoxy/C-NBR/CPP blends as adhesives for FPCs were studied. The micrographs measured by STEM showed that C-NBR is compatible with cured epoxy phases when a content of C-NBR is 30wt% or less and C-NBR forms micro domains when the content is 30wt% or over. Although, since the tanδ curves of cured blends plotted against temperature become broad with sifting toward a low temperature side when the C-NBR contents are increased, the above micro domains formed by cured epoxy phases and C-NBR phases would be composed with complex micro-phases or less separated morphologies having various relaxation times. Tensile strength of cured epoxy/C-NBR blends at breaking points shows the maximum value when a C-NBR content is 14wt%. The elongation at breaking points and the peel strength is increased when a C-NBR content is 30wt% or over respectively. And then they have the maximum value at 60wt% of a C-NBR content each other. Tolerance of electric resistance on cured epoxy/C-NBR blends is decreased in increasingtheC-NBR contents. Especially, it was found that electric resistance at a 60wt% of C-NBR content is decreased to an order of 108Ω and then that has been known as a big problem. Cured epoxy/C-NBR/CPP blends show VTM-0 of halogen-free flame-retardancy when a C-NBR content is 13wi%, i.e., phosphorus content is 1.7wt%. It was found that morphologies of the cured blends do not change very much when CPP is compounded by STEM and since the tanδ curves plotted against temperature shift toward a low temperature side, it was found that CPP is miscible with either phase of cure epoxies or C-NBR. Tensile strength at breaking points of cured blends containing CPP is decreased as the CPP content is increased. Both elongation at breaking points and peel strength of the cured blends shows the maximum value at a 13wt% of the CPP content. Therefore, it was found that CPP acts as a plasticizer. Insulation reliability of the cured blends is decreased by CPP. Especially, electric resistance at a 13wt% of a CPP content, where VTM-0 is achieved, is decreased to an order of 108Ω and that has been known as a big problem either.

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The transparent polymers (Organic-Glass) such as poly methyl methacrylate (PMMA), polycarbonate etc. have been widely utilized, because of the light and impact resistant properties.But, there isa disadvantage that the organic-glass is scratched easily.So we have prepared polysiloxane-typehard coating material in order to improve the scratch resistant property by low temperature curingfor PMMA.The coating material was composed of the tri-functional alkoxy silane hydrolysates and the curing catalyst (the basic alkaline metal salt as sodium acetate and　the organic acid as acetic acid).The obtained hard coating material has the characteristic properties which the coating solutionisstable, possible to be cured by low temperature (<100℃) and the coated film has the excellent surfacehardness, good adhesion for PMMA cast sheet, thermal resistance.

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