The polysilsesquioxane having glycidyl group were prepared from the corresponding trimethoxysilane by condensation in the presence of a catalytic amount of triethylamine. Analogously, the polysilsesquioxanes having glycidyl group with phenyl group or with methacrylate group were successfully prepared, in which the contents of the groups were adjusted to be almost equivalent.The adhesive property of such hybrid polymers were evaluated by measuring peel strength, in which copper plate and polyimide film were used as the base materials. The use of 10 equivalent of the curing agent, 2-ethyl-4-methylimidazole, to glycidyl group af 150℃ for curing led the polysilsesquioxanes to the good adhesives for the base materials. Even after the 20 times of thermal cycle test between -10℃ to 50℃, the polysilscsquioxanes showed the enough peel strength, which led to adherent failure of polyimide film. In addition, the glued materials by the polysilsesquioxanes, which were heated at 70℃ for 1 week, the peel strength test resulted in the adherent failure.

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A specimen configuration to measure the stress-strain relation of high ductile adhesives is proposed in this paper. Recently, high ductile adhesives, which are modified using rubber particles for instance, have been utilized to high performance joints due to their high lap-shear and peel strength. In order to design such joints using the adhesives, knowing their precise stress-strain relations is very important and essential. However, the strain measurement of high ductile adhesives is difficult in case of tensile tests because unstable deformation occurs locally at unspecified locus in the gauge part. A new variation of dumbbell specimen is suggested for overcoming the problem. Maximum deformed region is localized at the center of the specimen and the strain can be measured by conventional methods such as strain gauges.

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