The effects of tackifier addition on phase structures, viscoelasticity and the energy absorbability of pressure sensitive adhesives were studied. The adhesives consisting of acryl block copolymer blend (polymethylmethacrylate-poly-n-buthylacrylate-polymethylmethacrylate tri-block copolymer/polymethylmethacrylate-poly-n-buthylacrylate di-block copolymer) and several tackifiers (rosin ester, terpene phenol or petroleum resin) were formulated. The phase structures were determined using a transmission electron microscope and correlated to the viscoelastic behaviors obtained by dynamic mechanical analyses. Also, the energy absorbability and the load-displacement curves of the adhesives in impact/rebound process of a pendulum were evaluated using an instrumented pendulum impactor. Rosin ester or terpene phenol had relatively good compatibility with poly-n-buthylacrylate, and the energy absorbability of the blends increased within a particular range of the tackifier content. Whereas, petroleum resin had poor compatibility with the polymer blends, and the energy absorbability of the blends did not increased. It was clarified that the energy absorbability could be described as the dissipated heat energy calculated using both loss modulus as a viscoelastic parameter and measured maximum strain in the impact process.

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ITO (Indium-Tin-Oxide) has often been used in electronic devices because it has considerable transparency and high conductivity. In this study, we considered the mechanism of the degradation of ITO coated PET film by ITO accelerated photochemical oxidation. An ITO/PET film and a PET film were irradiated by UV-light. The weight loss of ITO/PET film during UV-irradiation was larger than that of PET film. X-ray photoemission spectroscopy showed that the intensity of C1s spectra for the bonding [O=C-O] and [-CO-] decreased in the area of PET closer to ITO layer. These indicated that ITO accelerated a decomposition of PET during UV-irradiation. In addition, the adhesive strength between ITO layer and epoxy resin decreased after UV-irradiation. Moreover, the electrochemical measurement showed the similar shift between ITO and TiO2 in the rest potential as UV-light switched on and off. This indicated that ITO could show the mechanism analogous to that of TiO2 for the degradation of polymer such as PET during UV-irradiation.

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The polysilsesquioxanes having chloromethylphenyl groups were prepared from the corresponding trimethoxysilanes by condensation under acidic or basic conditions. Such polysilsesquioxanes were utilized as the macroinitiators for the graft polymerization of block copolymer of acrylate monomers by ATRP process. From the results of the examination concerning the process, the combination of copper （I） bromide and (-)-sparteine was found to be an effective catalytic system for the graft polymerization without formation of cross-linked products. By the polymerization process, the block copolymers of methylmethacrylate with dodecyl methacrylate or butylacrylate, in which the sequence and molecular weight of the corresponding polymeric components were changed, were successfully grafted from the polysilsesquioxane backbone. Several physical properties such as thermal stability, adhesion force, probe tack and holding power were measured to evaluate the grafted polysilsesquioxanes for using as the hybrid adhesive materials.

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